v1.0.47 (#279)

* Add performance and stylus debugging logs

* Refactor and decouple UI models from `MainViewModel`

* Refactor library state management and projection logic

* Implement desktop shell using Compose Multiplatform

* Implement desktop shell using Compose Multiplatform

* Implement desktop shell using Compose Multiplatform

* Introduce ReaderEngine and enhance EPUB reader features in windows app

* Move core paginated reader logic to a Kotlin Multiplatform `shared` module and introduce experimental desktop support.

* Implement PDF rendering and text extraction for desktop using Pdfium

* Add `NonReaderScreens.kt` and UI dependencies

* Refactor and centralize library state management and models to improve cross-platform consistency

* Implement JSON persistence for desktop library and enhance library management features including shelf CRUD, tagging, and metadata editing

* Implement PDF annotation system and enhanced zoom controls for the desktop viewer

* Implement WebView-based EPUB rendering for desktop using CEF and embedded resources

* Optimize UI state projection, navigation state handling, and main screen pager performance

* Implement Bring Your Own Key (BYOK) support for AI features in OSS version

* Support Gemini-based Cloud TTS with BYOK support for OSS builds

* Refactor table cell image sizing in `PaginatedReader` and improve `MobiParser` native library loading and error handling.

* crash fixes

* Enhance navigation stability with lifecycle-aware safety checks and update `navigation-compose` to 2.9.6

* Implement dynamic bottom padding for the page info bar to account for device rounded corners

* Implement bidirectional jump history navigation and replace the jump-back pill with a dedicated `PdfJumpHistoryBar`

* Optimize PDF tiling performance and refine pan-and-fling gesture handling

* Implement customizable toolbars with drag-and-drop reordering and placement for PDF and EPUB readers

* Updated UI for customize toolbar

* Refine drag-and-drop reordering and section assignment for PDF and EPUB reader controls

* restructure PDF viewer UI component hierarchy to fix verifier crash

* Implement separate text dimming factors for light and dark themes

* Synchronize Pdfium access and improve resource lifecycle safety across Kotlin and native layers

* Enhance image alignment in paginated and EPUB readers through anchor detection and style-based positioning

* Centralize file type resolution logic and implement HTML sanitization during import

* Introduce vertical margin customization and configurable progress bar positioning

* texture support in epub reader

* Enhance TTS session management, progress tracking, and diagnostic logging

* Optimize library state projection and folder synchronization performance by refactoring collection lookups and refining metadata extraction logic.

* Refine TTS page mapping for PDF and overhaul TTS control UI

* Implement natural session completion logic in `TtsPlaybackManager` for cloud tts

* Replace Snackbar with `CustomTopBanner` for notifications in `PdfViewerScreen`

* Refine TTS playback continuity across PDF pages and improve state management for session transitions

* Implement global texture transparency and enhance textured theme support across PDF and EPUB readers.

* Update reader themes and improve texture rendering in page animations, EPUB UI, and immersive mode

* Add Support Project screen

* Optimize library performance via projection caching, batch database updates, and scoped folder synchronization.

* Enhance folder synchronization with fallback query mechanisms and refactor annotation sidecar importing logic

* Bump version to 1.0.47 (51)

.gitignore

@@ -8,7 +8,7 @@
 /.idea/navEditor.xml
 /.idea/assetWizardSettings.xml
 .DS_Store
-/build
+build/
 /captures
 .externalNativeBuild
 .cxx
@@ -18,3 +18,9 @@ local.properties
 google-services.json
 .kotlin/
 .idea/
+.gradle/
+third_party/pdfium/
+*.tgz
+kcef-bundle/
+cache/
+worker/

.idea/gradle.xml

@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="GradleMigrationSettings" migrationVersion="1" />
+  <component name="GradleSettings">
+    <option name="linkedExternalProjectsSettings">
+      <GradleProjectSettings>
+        <option name="testRunner" value="CHOOSE_PER_TEST" />
+        <option name="externalProjectPath" value="$PROJECT_DIR$" />
+        <option name="modules">
+          <set>
+            <option value="$PROJECT_DIR$" />
+            <option value="$PROJECT_DIR$/app" />
+            <option value="$PROJECT_DIR$/desktopApp" />
+            <option value="$PROJECT_DIR$/shared" />
+          </set>
+        </option>
+      </GradleProjectSettings>
+    </option>
+  </component>
+</project>

app/build.gradle.kts

@@ -24,14 +24,13 @@ kotlin {
 android {
     namespace = "com.aryan.reader"
     compileSdk = 36
-    ndkVersion = "29.0.14206865"
 
     defaultConfig {
         applicationId = "com.aryan.reader"
         minSdk = 26
         targetSdk = 35
-        versionCode = 46
-        versionName = "1.0.46"
+        versionCode = 51
+        versionName = "1.0.47"
 
         resourceConfigurations += setOf("en", "ar", "de", "tr", "fr", "ru")
 
@@ -154,6 +153,8 @@ android {
 //noinspection UseTomlInstead
 dependencies {
 
+    implementation(project(":shared"))
+
     implementation(libs.androidx.core.ktx)
     implementation(libs.androidx.lifecycle.runtime.ktx)
     implementation(libs.androidx.activity.compose)
@@ -190,7 +191,7 @@ dependencies {
     implementation("androidx.appcompat:appcompat:1.7.1")
 
     //noinspection GradleDependency (Updating these might cause the custom toolbox in pagination to break)
-    implementation("androidx.navigation:navigation-compose:2.9.2")
+    implementation("androidx.navigation:navigation-compose:2.9.6")
     //noinspection GradleDependency
     implementation("androidx.lifecycle:lifecycle-viewmodel-compose:2.9.2")
     //noinspection GradleDependency
@@ -241,6 +242,11 @@ dependencies {
 
     implementation("com.materialkolor:material-kolor:5.0.0-alpha07")
 
+    debugImplementation("org.tensorflow:tensorflow-lite:2.17.0")
+    debugImplementation("org.tensorflow:tensorflow-lite-support:0.5.0")
+    debugImplementation("org.tensorflow:tensorflow-lite-gpu:2.17.0")
+    debugImplementation("org.tensorflow:tensorflow-lite-gpu-api:2.17.0")
+
     implementation("androidx.core:core-splashscreen:1.2.0")
 
     testImplementation("junit:junit:4.13.2")

app/src/main/assets/epub_reader.js

@@ -189,7 +189,7 @@
         window.VIEWPORT_PADDING_BOTTOM = bottom || 0;
     };
 
-    window.applyReaderTheme = function (isDark, bgHex, textHex, textureBase64) {
+    window.applyReaderTheme = function (isDark, bgHex, textHex, textureBase64, textureAlpha) {
         var styleId = "readerThemeStyle";
         var themeStyleElement = document.getElementById(styleId);
 
@@ -207,8 +207,14 @@
         var effectiveBg = bgHex || (isDark ? '#121212' : '#FFFFFF');
         var effectiveText = textHex || (isDark ? '#E0E0E0' : '#000000');
 
+        var effectiveTextureAlpha = Math.max(0, Math.min(1, textureAlpha == null ? 0.55 : textureAlpha));
+        var bgMatch = /^#?([a-f\d]{2})([a-f\d]{2})([a-f\d]{2})$/i.exec(effectiveBg);
+        var bgRgb = bgMatch
+            ? `${parseInt(bgMatch[1], 16)}, ${parseInt(bgMatch[2], 16)}, ${parseInt(bgMatch[3], 16)}`
+            : (isDark ? '18, 18, 18' : '255, 255, 255');
+
         var textureCss = textureBase64
-            ? `background-image: url('${textureBase64}'); background-repeat: repeat; background-blend-mode: multiply;`
+            ? `background-image: linear-gradient(rgba(${bgRgb},${1 - effectiveTextureAlpha}), rgba(${bgRgb},${1 - effectiveTextureAlpha})), url('${textureBase64}'); background-repeat: repeat, repeat; background-blend-mode: normal, normal;`
             : 'background-image: none;';
 
         var css = `
@@ -517,7 +523,65 @@
         }
     }, true);
 
-    window.updateReaderStyles = function (fontSizeEm, lineHeight, fontFamily, textAlign, paragraphGap, imageSize, horizontalMargin) {
+    function getReaderImageElements() {
+        return Array.prototype.slice.call(document.querySelectorAll("img, svg, video, canvas, image"));
+    }
+
+    function rememberReaderImageAnchors() {
+        getReaderImageElements().forEach(function (image) {
+            if (image.getAttribute("data-reader-image-anchor")) return;
+
+            var parent = image.parentElement || document.body;
+            var imageRect = image.getBoundingClientRect();
+            var parentRect = parent.getBoundingClientRect();
+            var parentWidth = parentRect.width || document.documentElement.clientWidth || window.innerWidth || 0;
+
+            if (!parentWidth || imageRect.width <= 0) {
+                image.setAttribute("data-reader-image-anchor", "center");
+                return;
+            }
+
+            var imageCenter = imageRect.left + imageRect.width / 2;
+            var parentCenter = parentRect.left + parentWidth / 2;
+            var tolerance = Math.max(4, parentWidth * 0.08);
+            var anchor = "center";
+
+            if (Math.abs(imageCenter - parentCenter) <= tolerance || imageRect.width >= parentWidth - 2) {
+                anchor = "center";
+            } else if (imageCenter > parentCenter) {
+                anchor = "right";
+            } else {
+                anchor = "left";
+            }
+
+            image.setAttribute("data-reader-image-anchor", anchor);
+        });
+    }
+
+    function applyReaderImageAnchors() {
+        getReaderImageElements().forEach(function (image) {
+            var anchor = image.getAttribute("data-reader-image-anchor") || "center";
+
+            image.style.setProperty("display", "block", "important");
+            image.style.setProperty("height", "auto", "important");
+            image.style.setProperty("object-fit", "contain", "important");
+
+            if (anchor === "right") {
+                image.style.setProperty("float", "none", "important");
+                image.style.setProperty("margin-left", "auto", "important");
+                image.style.setProperty("margin-right", "0", "important");
+            } else if (anchor === "left") {
+                image.style.setProperty("margin-left", "0", "important");
+                image.style.setProperty("margin-right", "auto", "important");
+            } else {
+                image.style.setProperty("float", "none", "important");
+                image.style.setProperty("margin-left", "auto", "important");
+                image.style.setProperty("margin-right", "auto", "important");
+            }
+        });
+    }
+
+    window.updateReaderStyles = function (fontSizeEm, lineHeight, fontFamily, textAlign, paragraphGap, imageSize, horizontalMargin, verticalMargin) {
         var logTag = "ReaderFontDiagnosis";
         console.log(
             logTag +
@@ -534,7 +598,9 @@
                   ", ImageSize: " +
                   imageSize +
                   ", HorizontalMargin: " +
-                  horizontalMargin
+                  horizontalMargin +
+                  ", VerticalMargin: " +
+                  verticalMargin
           );
 
         var dynamicStyleId = "dynamicReaderStyles";
@@ -551,12 +617,16 @@
         var newGap = parseFloat(paragraphGap);
         var newImageSize = parseFloat(imageSize);
         var newHorizontalMargin = parseFloat(horizontalMargin);
+        var newVerticalMargin = parseFloat(verticalMargin);
 
         if (isNaN(newFontSize) || newFontSize < 0.5 || newFontSize > 5.0) newFontSize = 1.0;
         if (isNaN(newLineHeight) || newLineHeight < 1.0 || newLineHeight > 3.0) newLineHeight = 1.0;
         if (isNaN(newGap) || newGap < 0.0 || newGap > 3.0) newGap = 1.0;
         if (isNaN(newImageSize) || newImageSize < 0.5 || newImageSize > 2.0) newImageSize = 1.0;
         if (isNaN(newHorizontalMargin) || newHorizontalMargin < 0.0 || newHorizontalMargin > 3.0) newHorizontalMargin = 1.0;
+        if (isNaN(newVerticalMargin) || newVerticalMargin < 0.0 || newVerticalMargin > 3.0) newVerticalMargin = 1.0;
+
+        rememberReaderImageAnchors();
 
         var fontCss = "";
         if (fontFamily && fontFamily !== "Original" && fontFamily !== "") {
@@ -609,11 +679,14 @@
         }
 
         var horizontalPaddingPx = Math.max(0, 16 * newHorizontalMargin);
+        var verticalPaddingPx = Math.max(0, 16 * newVerticalMargin);
         var horizontalMarginCss = `
             body {
                 box-sizing: border-box !important;
                 padding-left: ${horizontalPaddingPx}px !important;
                 padding-right: ${horizontalPaddingPx}px !important;
+                padding-top: ${verticalPaddingPx}px !important;
+                padding-bottom: ${verticalPaddingPx}px !important;
             }
         `;
 
@@ -629,10 +702,22 @@
                 width: min(100%, calc(100% * var(--reader-image-size))) !important;
                 max-width: 100% !important;
                 height: auto !important;
+                display: block !important;
+                float: none !important;
+                margin-left: auto !important;
+                margin-right: auto !important;
+                object-fit: contain !important;
+            }
+            body p:has(> img:only-child),
+            body div:has(> img:only-child),
+            body figure {
+                text-align: center !important;
             }
         `;
 
         dynamicStyleElement.innerHTML = [sizeCss, lineHeightCss, fontCss, alignCss, gapCss, imageCss, horizontalMarginCss].join("\n");
+        applyReaderImageAnchors();
+        setTimeout(applyReaderImageAnchors, 80);
 
         setTimeout(
             function () {
@@ -2170,6 +2255,7 @@
             if (window.checkImagesForDiagnosis) {
                 setTimeout(window.checkImagesForDiagnosis, 100);
             }
+            setTimeout(applyReaderImageAnchors, 80);
         },
     };
 

app/src/main/cpp/pdfium_bridge.cpp

@@ -52,7 +52,7 @@ static FPDFLink_GetDest_t get_dest_func = nullptr;
 static FPDFAction_GetDest_t get_action_dest_func = nullptr;
 static FPDFDest_GetDestPageIndex_t get_dest_page_index_func = nullptr;
 static FPDFAction_GetFilePath_t get_file_path_func = nullptr;
-static std::mutex g_pdfium_mutex;
+static std::recursive_mutex g_pdfium_mutex;
 static FPDFLink_GetAnnot_t get_link_annot_func = nullptr;
 static FPDFLink_GetAction_t get_link_action_func = nullptr;
 static FPDFAction_GetType_t get_action_type_func = nullptr;
@@ -169,20 +169,23 @@ static bool init_pdfium() {
 
 extern "C" JNIEXPORT jdouble JNICALL
 Java_com_aryan_reader_pdf_NativePdfiumBridge_getFontSize(JNIEnv *env, jclass clazz, jlong textPagePtr, jint index) {
-    if (!init_pdfium() || !get_font_size_func) return 0.0;
+    std::lock_guard<std::recursive_mutex> lock(g_pdfium_mutex);
+    if (!init_pdfium() || !get_font_size_func || textPagePtr == 0 || index < 0) return 0.0;
     return get_font_size_func(reinterpret_cast<void*>(textPagePtr), index);
 }
 
 extern "C" JNIEXPORT jint JNICALL
 Java_com_aryan_reader_pdf_NativePdfiumBridge_getFontWeight(JNIEnv *env, jclass clazz, jlong textPagePtr, jint index) {
-    if (!init_pdfium() || !get_font_weight_func) return 0;
+    std::lock_guard<std::recursive_mutex> lock(g_pdfium_mutex);
+    if (!init_pdfium() || !get_font_weight_func || textPagePtr == 0 || index < 0) return 0;
     return get_font_weight_func(reinterpret_cast<void*>(textPagePtr), index);
 }
 
 // Bulk extraction for blazing fast formatting processing
 extern "C" JNIEXPORT jfloatArray JNICALL
 Java_com_aryan_reader_pdf_NativePdfiumBridge_getPageFontSizes(JNIEnv *env, jclass clazz, jlong textPagePtr, jint count) {
-    if (!init_pdfium() || !get_font_size_func || count <= 0) return nullptr;
+    std::lock_guard<std::recursive_mutex> lock(g_pdfium_mutex);
+    if (!init_pdfium() || !get_font_size_func || textPagePtr == 0 || count <= 0) return nullptr;
 
     jfloatArray result = env->NewFloatArray(count);
     jfloat *fill = new jfloat[count];
@@ -196,7 +199,8 @@ Java_com_aryan_reader_pdf_NativePdfiumBridge_getPageFontSizes(JNIEnv *env, jclas
 
 extern "C" JNIEXPORT jintArray JNICALL
 Java_com_aryan_reader_pdf_NativePdfiumBridge_getPageFontWeights(JNIEnv *env, jclass clazz, jlong textPagePtr, jint count) {
-    if (!init_pdfium() || !get_font_weight_func || count <= 0) return nullptr;
+    std::lock_guard<std::recursive_mutex> lock(g_pdfium_mutex);
+    if (!init_pdfium() || !get_font_weight_func || textPagePtr == 0 || count <= 0) return nullptr;
 
     jintArray result = env->NewIntArray(count);
     jint *fill = new jint[count];
@@ -210,7 +214,8 @@ Java_com_aryan_reader_pdf_NativePdfiumBridge_getPageFontWeights(JNIEnv *env, jcl
 
 extern "C" JNIEXPORT jintArray JNICALL
 Java_com_aryan_reader_pdf_NativePdfiumBridge_getPageFontFlags(JNIEnv *env, jclass clazz, jlong textPagePtr, jint count) {
-    if (!init_pdfium() || !get_font_info_func || count <= 0) return nullptr;
+    std::lock_guard<std::recursive_mutex> lock(g_pdfium_mutex);
+    if (!init_pdfium() || !get_font_info_func || textPagePtr == 0 || count <= 0) return nullptr;
 
     jintArray result = env->NewIntArray(count);
     jint *fill = new jint[count];
@@ -226,7 +231,8 @@ Java_com_aryan_reader_pdf_NativePdfiumBridge_getPageFontFlags(JNIEnv *env, jclas
 
 extern "C" JNIEXPORT jfloatArray JNICALL
 Java_com_aryan_reader_pdf_NativePdfiumBridge_getPageCharBoxes(JNIEnv *env, jclass clazz, jlong textPagePtr, jint count) {
-    if (!init_pdfium() || !get_char_box_func || count <= 0) return nullptr;
+    std::lock_guard<std::recursive_mutex> lock(g_pdfium_mutex);
+    if (!init_pdfium() || !get_char_box_func || textPagePtr == 0 || count <= 0) return nullptr;
 
     const int stride = 4;
     jfloatArray result = env->NewFloatArray(count * stride);
@@ -247,7 +253,7 @@ Java_com_aryan_reader_pdf_NativePdfiumBridge_getPageCharBoxes(JNIEnv *env, jclas
 
 extern "C" JNIEXPORT jstring JNICALL
 Java_com_aryan_reader_pdf_NativePdfiumBridge_getAnnotString(JNIEnv *env, jclass clazz, jlong pagePtr, jint index, jstring key) {
-    std::lock_guard<std::mutex> lock(g_pdfium_mutex);
+    std::lock_guard<std::recursive_mutex> lock(g_pdfium_mutex);
     if (!init_pdfium() || !get_annot_func || !get_annot_string_func || pagePtr == 0) return nullptr;
 
     void* page = reinterpret_cast<void*>(pagePtr);
@@ -294,24 +300,23 @@ Java_com_aryan_reader_pdf_NativePdfiumBridge_getAnnotString(JNIEnv *env, jclass
 
 extern "C" JNIEXPORT jint JNICALL
 Java_com_aryan_reader_pdf_NativePdfiumBridge_getPageObjectCount(JNIEnv *env, jclass clazz, jlong pagePtr) {
-    if (!init_pdfium() || !count_objects_func) return 0;
+    std::lock_guard<std::recursive_mutex> lock(g_pdfium_mutex);
+    if (!init_pdfium() || !count_objects_func || pagePtr == 0) return 0;
     return count_objects_func(reinterpret_cast<void*>(pagePtr));
 }
 
 extern "C" JNIEXPORT jint JNICALL
 Java_com_aryan_reader_pdf_NativePdfiumBridge_getPageObjectType(JNIEnv *env, jclass clazz, jlong pagePtr, jint index) {
-    if (!init_pdfium() || !count_objects_func || !get_object_func || !get_object_type_func || pagePtr == 0 || index < 0) return 0;
-    const int object_count = count_objects_func(reinterpret_cast<void*>(pagePtr));
-    if (index >= object_count) return 0;
+    std::lock_guard<std::recursive_mutex> lock(g_pdfium_mutex);
+    if (!init_pdfium() || !get_object_func || !get_object_type_func || pagePtr == 0 || index < 0) return 0;
     void* obj = get_object_func(reinterpret_cast<void*>(pagePtr), index);
     return obj ? get_object_type_func(obj) : 0;
 }
 
 extern "C" JNIEXPORT jboolean JNICALL
 Java_com_aryan_reader_pdf_NativePdfiumBridge_getPageObjectBoundingBox(JNIEnv *env, jclass clazz, jlong pagePtr, jint index, jfloatArray outRect) {
-    if (!init_pdfium() || !count_objects_func || !get_object_func || !get_object_bounds_func || pagePtr == 0 || index < 0 || outRect == nullptr) return JNI_FALSE;
-    const int object_count = count_objects_func(reinterpret_cast<void*>(pagePtr));
-    if (index >= object_count) return JNI_FALSE;
+    std::lock_guard<std::recursive_mutex> lock(g_pdfium_mutex);
+    if (!init_pdfium() || !get_object_func || !get_object_bounds_func || pagePtr == 0 || index < 0 || outRect == nullptr) return JNI_FALSE;
     void* obj = get_object_func(reinterpret_cast<void*>(pagePtr), index);
     if (!obj) return JNI_FALSE;
 
@@ -326,9 +331,13 @@ Java_com_aryan_reader_pdf_NativePdfiumBridge_getPageObjectBoundingBox(JNIEnv *en
 
 extern "C" JNIEXPORT jintArray JNICALL
 Java_com_aryan_reader_pdf_NativePdfiumBridge_extractImagePixels(JNIEnv *env, jclass clazz, jlong pagePtr, jint index, jintArray dimens) {
-    if (!init_pdfium() || !count_objects_func || !get_object_func || !get_object_type_func || !get_image_bitmap_func || !bitmap_get_buffer_func || pagePtr == 0 || index < 0 || dimens == nullptr) return nullptr;
-    const int object_count = count_objects_func(reinterpret_cast<void*>(pagePtr));
-    if (index >= object_count) return nullptr;
+    std::lock_guard<std::recursive_mutex> lock(g_pdfium_mutex);
+    if (!init_pdfium() || !get_object_func || !get_object_type_func || !get_image_bitmap_func ||
+        !bitmap_get_width_func || !bitmap_get_height_func || !bitmap_get_stride_func ||
+        !bitmap_get_buffer_func || !bitmap_destroy_func ||
+        pagePtr == 0 || index < 0 || dimens == nullptr) {
+        return nullptr;
+    }
 
     void* obj = get_object_func(reinterpret_cast<void*>(pagePtr), index);
     if (!obj || get_object_type_func(obj) != 3) return nullptr; // 3 = FPDF_PAGEOBJ_IMAGE
@@ -379,6 +388,7 @@ Java_com_aryan_reader_pdf_NativePdfiumBridge_extractImagePixels(JNIEnv *env, jcl
 
 extern "C" JNIEXPORT jboolean JNICALL
 Java_com_aryan_reader_pdf_NativePdfiumBridge_checkActionSupport(JNIEnv *env, jclass clazz) {
+    std::lock_guard<std::recursive_mutex> lock(g_pdfium_mutex);
     init_pdfium();
     // Return true if we have ANY way to handle actions
     return (do_annot_action_func || get_link_action_func) ? JNI_TRUE : JNI_FALSE;
@@ -386,6 +396,7 @@ Java_com_aryan_reader_pdf_NativePdfiumBridge_checkActionSupport(JNIEnv *env, jcl
 
 extern "C" JNIEXPORT jint JNICALL
 Java_com_aryan_reader_pdf_NativePdfiumBridge_getAnnotSubtypeAtPoint(JNIEnv *env, jclass clazz, jlong pagePtr, jdouble x, jdouble y) {
+    std::lock_guard<std::recursive_mutex> lock(g_pdfium_mutex);
     if (!init_pdfium() || !get_annot_count_func || pagePtr == 0) return -1;
 
     void* page = reinterpret_cast<void*>(pagePtr);
@@ -412,6 +423,7 @@ Java_com_aryan_reader_pdf_NativePdfiumBridge_getAnnotSubtypeAtPoint(JNIEnv *env,
 
 extern "C" JNIEXPORT jfloatArray JNICALL
 Java_com_aryan_reader_pdf_NativePdfiumBridge_getAnnotRectAtPoint(JNIEnv *env, jclass clazz, jlong pagePtr, jdouble x, jdouble y) {
+    std::lock_guard<std::recursive_mutex> lock(g_pdfium_mutex);
     if (!init_pdfium() || !get_annot_count_func || !get_annot_func || !get_annot_rect_func || pagePtr == 0) return nullptr;
 
     void* page = reinterpret_cast<void*>(pagePtr);
@@ -432,13 +444,14 @@ Java_com_aryan_reader_pdf_NativePdfiumBridge_getAnnotRectAtPoint(JNIEnv *env, jc
 
 extern "C" JNIEXPORT jint JNICALL
 Java_com_aryan_reader_pdf_NativePdfiumBridge_getAnnotCount(JNIEnv *env, jclass clazz, jlong pagePtr) {
-    std::lock_guard<std::mutex> lock(g_pdfium_mutex);
+    std::lock_guard<std::recursive_mutex> lock(g_pdfium_mutex);
     if (!init_pdfium() || !get_annot_count_func || pagePtr == 0) return 0;
     return get_annot_count_func(reinterpret_cast<void*>(pagePtr));
 }
 
 extern "C" JNIEXPORT jint JNICALL
 Java_com_aryan_reader_pdf_NativePdfiumBridge_getAnnotSubtype(JNIEnv *env, jclass clazz, jlong pagePtr, jint index) {
+    std::lock_guard<std::recursive_mutex> lock(g_pdfium_mutex);
     if (!init_pdfium() || !get_annot_func || !get_annot_subtype_func || pagePtr == 0) return 0;
     void* annot = get_annot_func(reinterpret_cast<void*>(pagePtr), index);
     return annot ? get_annot_subtype_func(annot) : 0;
@@ -446,6 +459,7 @@ Java_com_aryan_reader_pdf_NativePdfiumBridge_getAnnotSubtype(JNIEnv *env, jclass
 
 extern "C" JNIEXPORT jfloatArray JNICALL
 Java_com_aryan_reader_pdf_NativePdfiumBridge_getAnnotRect(JNIEnv *env, jclass clazz, jlong pagePtr, jint index) {
+    std::lock_guard<std::recursive_mutex> lock(g_pdfium_mutex);
     if (!init_pdfium() || !get_annot_func || !get_annot_rect_func || pagePtr == 0) return nullptr;
     void* annot = get_annot_func(reinterpret_cast<void*>(pagePtr), index);
     if (!annot) return nullptr;
@@ -460,7 +474,7 @@ Java_com_aryan_reader_pdf_NativePdfiumBridge_getAnnotRect(JNIEnv *env, jclass cl
 
 extern "C" JNIEXPORT jboolean JNICALL
 Java_com_aryan_reader_pdf_NativePdfiumBridge_performClick(JNIEnv *env, jclass clazz, jlong pagePtr, jdouble x, jdouble y) {
-    std::lock_guard<std::mutex> lock(g_pdfium_mutex);
+    std::lock_guard<std::recursive_mutex> lock(g_pdfium_mutex);
     if (!init_pdfium() || pagePtr == 0) return JNI_FALSE;
 
     void* page = reinterpret_cast<void*>(pagePtr);
@@ -527,7 +541,7 @@ Java_com_aryan_reader_pdf_NativePdfiumBridge_performClick(JNIEnv *env, jclass cl
 
 extern "C" JNIEXPORT jstring JNICALL
 Java_com_aryan_reader_pdf_NativePdfiumBridge_getLinkInfoAtPoint(JNIEnv *env, jclass clazz, jlong docPtr, jlong pagePtr, jdouble x, jdouble y) {
-    std::lock_guard<std::mutex> lock(g_pdfium_mutex);
+    std::lock_guard<std::recursive_mutex> lock(g_pdfium_mutex);
     if (!init_pdfium()) {
         LOGE("PdfLinkDiagnostic: init_pdfium failed.");
         return nullptr;

app/src/main/java/com/aryan/reader/AiSettingsScreen.kt

@@ -0,0 +1,314 @@
+package com.aryan.reader
+
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.statusBarsPadding
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.verticalScroll
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.ArrowBack
+import androidx.compose.material.icons.filled.Check
+import androidx.compose.material.icons.filled.Delete
+import androidx.compose.material3.AlertDialog
+import androidx.compose.material3.Button
+import androidx.compose.material3.DropdownMenuItem
+import androidx.compose.material3.ExperimentalMaterial3Api
+import androidx.compose.material3.ExposedDropdownMenuBox
+import androidx.compose.material3.ExposedDropdownMenuDefaults
+import androidx.compose.material3.HorizontalDivider
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.ListItem
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.OutlinedTextField
+import androidx.compose.material3.Scaffold
+import androidx.compose.material3.Switch
+import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.text.input.PasswordVisualTransformation
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.unit.dp
+
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+fun AiSettingsScreen(
+    onBackClick: () -> Unit
+) {
+    val context = LocalContext.current
+    var settings by remember { mutableStateOf(loadAiByokSettings(context)) }
+    var selectedProvider by remember { mutableStateOf("gemini") }
+    var providerMenuExpanded by remember { mutableStateOf(false) }
+    var pendingKey by remember { mutableStateOf("") }
+    var showSaveConfirm by remember { mutableStateOf(false) }
+    var providerToDelete by remember { mutableStateOf<String?>(null) }
+
+    fun refresh() {
+        settings = loadAiByokSettings(context)
+    }
+
+    fun updateModels(newSettings: AiByokSettings) {
+        saveAiByokSettings(context, newSettings)
+        settings = loadAiByokSettings(context)
+    }
+
+    Scaffold(
+        modifier = Modifier.statusBarsPadding(),
+        topBar = {
+            CustomTopAppBar(
+                title = { Text("AI keys and models") },
+                navigationIcon = {
+                    IconButton(onClick = onBackClick) {
+                        Icon(Icons.AutoMirrored.Filled.ArrowBack, contentDescription = "Back")
+                    }
+                }
+            )
+        }
+    ) { padding ->
+        Column(
+            modifier = Modifier
+                .fillMaxSize()
+                .padding(padding)
+                .verticalScroll(rememberScrollState())
+                .padding(20.dp),
+            verticalArrangement = Arrangement.spacedBy(16.dp)
+        ) {
+            Text("Saved keys", style = MaterialTheme.typography.titleMedium, fontWeight = FontWeight.SemiBold)
+            SavedKeyRow("Gemini", maskedAiByokKey(context, "gemini"), onDelete = { providerToDelete = "gemini" })
+            SavedKeyRow("Groq", maskedAiByokKey(context, "groq"), onDelete = { providerToDelete = "groq" })
+
+            HorizontalDivider()
+
+            Text("Add or replace key", style = MaterialTheme.typography.titleMedium, fontWeight = FontWeight.SemiBold)
+            ExposedDropdownMenuBox(
+                expanded = providerMenuExpanded,
+                onExpandedChange = { providerMenuExpanded = it },
+                modifier = Modifier.fillMaxWidth()
+            ) {
+                OutlinedTextField(
+                    value = selectedProvider.replaceFirstChar { it.titlecase() },
+                    onValueChange = {},
+                    readOnly = true,
+                    label = { Text("Provider") },
+                    trailingIcon = { ExposedDropdownMenuDefaults.TrailingIcon(expanded = providerMenuExpanded) },
+                    modifier = Modifier.fillMaxWidth().menuAnchor()
+                )
+                ExposedDropdownMenu(
+                    expanded = providerMenuExpanded,
+                    onDismissRequest = { providerMenuExpanded = false }
+                ) {
+                    listOf("gemini", "groq").forEach { provider ->
+                        DropdownMenuItem(
+                            text = { Text(provider.replaceFirstChar { it.titlecase() }) },
+                            onClick = {
+                                selectedProvider = provider
+                                providerMenuExpanded = false
+                            },
+                            trailingIcon = if (provider == selectedProvider) {
+                                { Icon(Icons.Default.Check, contentDescription = null) }
+                            } else null
+                        )
+                    }
+                }
+            }
+            OutlinedTextField(
+                value = pendingKey,
+                onValueChange = { pendingKey = it },
+                label = { Text("API key") },
+                singleLine = true,
+                visualTransformation = PasswordVisualTransformation(),
+                modifier = Modifier.fillMaxWidth()
+            )
+            Button(
+                onClick = { showSaveConfirm = true },
+                enabled = pendingKey.isNotBlank(),
+                modifier = Modifier.align(Alignment.End)
+            ) {
+                Text("Save key")
+            }
+
+            HorizontalDivider()
+
+            Row(
+                modifier = Modifier.fillMaxWidth(),
+                verticalAlignment = Alignment.CenterVertically,
+                horizontalArrangement = Arrangement.SpaceBetween
+            ) {
+                Column(modifier = Modifier.weight(1f)) {
+                    Text("Use one model for all features", style = MaterialTheme.typography.titleMedium)
+                    Text(
+                        "When off, each reader AI feature uses its own selected model.",
+                        style = MaterialTheme.typography.bodySmall,
+                        color = MaterialTheme.colorScheme.onSurfaceVariant
+                    )
+                }
+                Switch(
+                    checked = settings.useOneModel,
+                    onCheckedChange = { updateModels(settings.copy(useOneModel = it)) }
+                )
+            }
+
+            if (settings.useOneModel) {
+                ModelSelector(
+                    title = "All AI features",
+                    description = "Smart dictionary, summaries, and recaps all use this model.",
+                    selectedId = settings.modelForAll,
+                    onSelected = { updateModels(settings.copy(modelForAll = it)) }
+                )
+            } else {
+                ModelSelector(
+                    title = "Smart dictionary",
+                    description = "Used when defining selected words or phrases.",
+                    selectedId = settings.defineModel,
+                    onSelected = { updateModels(settings.copy(defineModel = it)) }
+                )
+                ModelSelector(
+                    title = "Summaries",
+                    description = "Used for EPUB summaries and PDF page summaries. PDF/image summaries need Gemini.",
+                    selectedId = settings.summarizeModel,
+                    onSelected = { updateModels(settings.copy(summarizeModel = it)) }
+                )
+                ModelSelector(
+                    title = "Recaps",
+                    description = "Used for story recap generation.",
+                    selectedId = settings.recapModel,
+                    onSelected = { updateModels(settings.copy(recapModel = it)) }
+                )
+            }
+
+            ModelSelector(
+                title = "Cloud TTS",
+                description = "Uses the saved Gemini key. Only $GEMINI_CLOUD_TTS_MODEL is supported for now.",
+                selectedId = settings.ttsModel,
+                options = listOf(AiModelOption("gemini", GEMINI_CLOUD_TTS_MODEL)),
+                onSelected = { updateModels(settings.copy(ttsModel = it)) }
+            )
+        }
+    }
+
+    if (showSaveConfirm) {
+        AlertDialog(
+            onDismissRequest = { showSaveConfirm = false },
+            title = { Text("Save ${selectedProvider.replaceFirstChar { it.titlecase() }} key?") },
+            text = { Text("After saving, only the first 3 and last 3 characters will be visible. To change it later, replace or delete it.") },
+            confirmButton = {
+                TextButton(onClick = {
+                    saveAiByokKey(context, selectedProvider, pendingKey)
+                    pendingKey = ""
+                    showSaveConfirm = false
+                    refresh()
+                }) { Text("Save") }
+            },
+            dismissButton = {
+                TextButton(onClick = { showSaveConfirm = false }) { Text("Cancel") }
+            }
+        )
+    }
+
+    providerToDelete?.let { provider ->
+        AlertDialog(
+            onDismissRequest = { providerToDelete = null },
+            title = { Text("Delete ${provider.replaceFirstChar { it.titlecase() }} key?") },
+            text = { Text("Features using this provider will stop working until a new key is saved.") },
+            confirmButton = {
+                TextButton(onClick = {
+                    deleteAiByokKey(context, provider)
+                    providerToDelete = null
+                    refresh()
+                }) { Text("Delete") }
+            },
+            dismissButton = {
+                TextButton(onClick = { providerToDelete = null }) { Text("Cancel") }
+            }
+        )
+    }
+}
+
+@Composable
+private fun SavedKeyRow(
+    label: String,
+    maskedKey: String,
+    onDelete: () -> Unit
+) {
+    ListItem(
+        headlineContent = { Text(label) },
+        supportingContent = {
+            Text(maskedKey.ifBlank { "No key saved" })
+        },
+        trailingContent = {
+            IconButton(onClick = onDelete, enabled = maskedKey.isNotBlank()) {
+                Icon(Icons.Default.Delete, contentDescription = "Delete $label key")
+            }
+        }
+    )
+}
+
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+private fun ModelSelector(
+    title: String,
+    description: String,
+    selectedId: String,
+    options: List<AiModelOption> = aiByokModelOptions,
+    onSelected: (String) -> Unit
+) {
+    var expanded by remember { mutableStateOf(false) }
+    val selected = options.firstOrNull { it.id == selectedId }
+
+    Column(verticalArrangement = Arrangement.spacedBy(6.dp)) {
+        Text(title, style = MaterialTheme.typography.titleMedium, fontWeight = FontWeight.SemiBold)
+        Text(description, style = MaterialTheme.typography.bodySmall, color = MaterialTheme.colorScheme.onSurfaceVariant)
+        ExposedDropdownMenuBox(
+            expanded = expanded,
+            onExpandedChange = { expanded = it },
+            modifier = Modifier.fillMaxWidth()
+        ) {
+            OutlinedTextField(
+                value = selected?.label ?: "No model selected",
+                onValueChange = {},
+                readOnly = true,
+                label = { Text("Model") },
+                trailingIcon = { ExposedDropdownMenuDefaults.TrailingIcon(expanded = expanded) },
+                modifier = Modifier.fillMaxWidth().menuAnchor()
+            )
+            ExposedDropdownMenu(
+                expanded = expanded,
+                onDismissRequest = { expanded = false }
+            ) {
+                DropdownMenuItem(
+                    text = { Text("No model selected") },
+                    onClick = {
+                        onSelected("")
+                        expanded = false
+                    },
+                    trailingIcon = if (selectedId.isBlank()) {
+                        { Icon(Icons.Default.Check, contentDescription = null) }
+                    } else null
+                )
+                options.forEach { option ->
+                    DropdownMenuItem(
+                        text = { Text(option.label) },
+                        onClick = {
+                            onSelected(option.id)
+                            expanded = false
+                        },
+                        trailingIcon = if (option.id == selected?.id) {
+                            { Icon(Icons.Default.Check, contentDescription = null) }
+                        } else null
+                    )
+                }
+            }
+        }
+    }
+}

app/src/main/java/com/aryan/reader/AndroidFolderPathResolver.kt

@@ -0,0 +1,53 @@
+package com.aryan.reader
+
+import android.net.Uri
+import androidx.core.net.toUri
+import com.aryan.reader.data.RecentFileItem
+import timber.log.Timber
+
+class AndroidFolderPathResolver : FolderPathResolver {
+    override fun relativeFolderSegments(item: RecentFileItem): List<String> {
+        val documentUriString = item.uriString ?: return emptyList()
+        val rootFolderUriString = item.sourceFolderUri ?: return emptyList()
+
+        return try {
+            val documentUri = documentUriString.toUri()
+            val rootFolderUri = rootFolderUriString.toUri()
+            val rootDocId = rootFolderUri.treeDocumentIdOrNull() ?: return emptyList()
+            val documentId = documentUri.documentIdOrNull() ?: return emptyList()
+
+            val rootPath = rootDocId.substringAfter(':', "")
+            val documentPath = documentId.substringAfter(':', "")
+            val relativeDocumentPath = when {
+                rootPath.isBlank() -> documentPath
+                documentPath == rootPath -> ""
+                documentPath.startsWith("$rootPath/") -> documentPath.removePrefix("$rootPath/")
+                else -> documentPath
+            }
+
+            relativeDocumentPath
+                .substringBeforeLast('/', "")
+                .split('/')
+                .map { Uri.decode(it).trim() }
+                .filter { it.isNotEmpty() }
+        } catch (e: Exception) {
+            Timber.tag("FolderShelves").w(e, "Failed to derive relative folder path for ${item.displayName}")
+            emptyList()
+        }
+    }
+
+    private fun Uri.treeDocumentIdOrNull(): String? {
+        val segments = pathSegments
+        val treeIndex = segments.indexOf("tree")
+        return segments.getOrNull(treeIndex + 1)
+    }
+
+    private fun Uri.documentIdOrNull(): String? {
+        val segments = pathSegments
+        val documentIndex = segments.indexOf("document")
+        if (documentIndex >= 0) {
+            return segments.getOrNull(documentIndex + 1)
+        }
+        return treeDocumentIdOrNull()
+    }
+}

app/src/main/java/com/aryan/reader/AppNavigation.kt

@@ -43,13 +43,18 @@ import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.unit.dp
+import androidx.lifecycle.Lifecycle
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import androidx.media3.common.util.UnstableApi
 import androidx.navigation.NavHostController
 import androidx.navigation.compose.NavHost
 import androidx.navigation.compose.composable
+import androidx.navigation.compose.currentBackStackEntryAsState
 import com.aryan.reader.epubreader.EpubReaderScreen
 import com.aryan.reader.feedback.FeedbackScreen
+import com.aryan.reader.feedback.SupportProjectScreen
 import com.aryan.reader.pdf.PdfViewerScreen
+import kotlinx.coroutines.delay
 
 object AppDestinations {
     const val MAIN_ROUTE = "main"
@@ -57,19 +62,74 @@ object AppDestinations {
     const val EPUB_READER_ROUTE = "epub_reader"
     const val PRO_SCREEN_ROUTE = "pro_screen"
     const val FEEDBACK_SCREEN_ROUTE = "feedback_screen_route"
+    const val SUPPORT_PROJECT_SCREEN_ROUTE = "support_project_screen_route"
     const val FONTS_SCREEN_ROUTE = "fonts_screen_route"
+    const val AI_SETTINGS_SCREEN_ROUTE = "ai_settings_screen_route"
+}
+
+private fun NavHostController.isReadyForBackStackChange(): Boolean {
+    return currentBackStackEntry?.lifecycle?.currentState == Lifecycle.State.RESUMED
+}
+
+private suspend fun NavHostController.awaitReadyForBackStackChange() {
+    while (!isReadyForBackStackChange()) {
+        delay(32)
+    }
 }
 
 private fun NavHostController.navigateSingleTopTo(route: String) {
-    navigate(route) {
-        launchSingleTop = true
-        restoreState = true
-        popUpTo(graph.startDestinationId) {
-            saveState = true
+    if (!isReadyForBackStackChange()) {
+        Timber.d("Skipping navigation to $route because the current entry is not resumed yet.")
+        return
+    }
+
+    try {
+        navigate(route) {
+            launchSingleTop = true
+            popUpTo(graph.startDestinationId) {
+                saveState = false
+            }
+        }
+    } catch (e: IllegalStateException) {
+        Timber.w(e, "Navigation to $route ignored because the back stack is mid-transition.")
+    }
+}
+
+private fun NavHostController.navigateToMain() {
+    navigateSingleTopTo(AppDestinations.MAIN_ROUTE)
+}
+
+private fun NavHostController.navigateIfReady(route: String) {
+    if (currentDestination?.route == route) return
+    navigateSingleTopTo(route)
+}
+
+private fun NavHostController.popBackStackIfReady(): Boolean {
+    if (!isReadyForBackStackChange()) {
+        Timber.d("Skipping popBackStack because the current entry is not resumed yet.")
+        return false
+    }
+
+    return try {
+        popBackStack()
+    } catch (e: IllegalStateException) {
+        Timber.w(e, "popBackStack ignored because the back stack is mid-transition.")
+        false
+    }
+}
+
+private suspend fun NavHostController.syncRouteTo(route: String) {
+    awaitReadyForBackStackChange()
+    if (currentDestination?.route != route) {
+        if (route == AppDestinations.MAIN_ROUTE) {
+            navigateToMain()
+        } else {
+            navigateSingleTopTo(route)
         }
     }
 }
 
+@androidx.annotation.OptIn(UnstableApi::class)
 @OptIn(ExperimentalMaterial3Api::class)
 @RequiresApi(Build.VERSION_CODES.VANILLA_ICE_CREAM)
 @Composable
@@ -80,34 +140,31 @@ fun AppNavigation(
 ) {
     Timber.d("AppNavigation composable invoked.")
     val uiState by viewModel.uiState.collectAsStateWithLifecycle()
+    val currentBackStackEntry by navController.currentBackStackEntryAsState()
+    val currentRoute = currentBackStackEntry?.destination?.route
 
-    LaunchedEffect(uiState.selectedFileType, uiState.isLoading, uiState.selectedEpubBook, uiState.selectedPdfUri) {
+    LaunchedEffect(currentRoute, uiState.selectedFileType, uiState.isLoading, uiState.selectedEpubBook, uiState.selectedPdfUri) {
         if (!uiState.isLoading) {
-            try {
-                when (uiState.selectedFileType) {
-                    FileType.PDF, FileType.CBZ, FileType.CBR, FileType.CB7 -> {
-                        if (uiState.selectedPdfUri != null) {
-                            if (navController.currentDestination?.route != AppDestinations.PDF_VIEWER_ROUTE) {
-                                navController.navigateSingleTopTo(AppDestinations.PDF_VIEWER_ROUTE)
-                            }
-                        }
-                    }
-                    FileType.EPUB, FileType.MOBI, FileType.MD, FileType.TXT, FileType.HTML, FileType.FB2, FileType.DOCX, FileType.ODT, FileType.FODT -> {
-                        if (uiState.selectedEpubBook != null) {
-                            if (navController.currentDestination?.route != AppDestinations.EPUB_READER_ROUTE) {
-                                navController.navigateSingleTopTo(AppDestinations.EPUB_READER_ROUTE)
-                            }
-                        }
-                    }
-                    null -> {
-                        val currentRoute = navController.currentBackStackEntry?.destination?.route
-                        if (currentRoute != null && currentRoute != AppDestinations.MAIN_ROUTE) {
-                            navController.navigateSingleTopTo(AppDestinations.MAIN_ROUTE)
+            when (uiState.selectedFileType) {
+                FileType.PDF, FileType.CBZ, FileType.CBR, FileType.CB7 -> {
+                    if (uiState.selectedPdfUri != null) {
+                        if (currentRoute != AppDestinations.PDF_VIEWER_ROUTE) {
+                            navController.syncRouteTo(AppDestinations.PDF_VIEWER_ROUTE)
                         }
                     }
                 }
-            } catch (e: IllegalStateException) {
-                Timber.w(e, "Navigation transition already in progress, ignoring.")
+                FileType.EPUB, FileType.MOBI, FileType.MD, FileType.TXT, FileType.HTML, FileType.FB2, FileType.DOCX, FileType.ODT, FileType.FODT -> {
+                    if (uiState.selectedEpubBook != null) {
+                        if (currentRoute != AppDestinations.EPUB_READER_ROUTE) {
+                            navController.syncRouteTo(AppDestinations.EPUB_READER_ROUTE)
+                        }
+                    }
+                }
+                null -> {
+                    if (currentRoute == AppDestinations.PDF_VIEWER_ROUTE || currentRoute == AppDestinations.EPUB_READER_ROUTE) {
+                        navController.syncRouteTo(AppDestinations.MAIN_ROUTE)
+                    }
+                }
             }
         }
     }
@@ -153,7 +210,7 @@ fun AppNavigation(
                             }
                         },
                         onNavigateToPro = {
-                            navController.navigate(AppDestinations.PRO_SCREEN_ROUTE)
+                            navController.navigateIfReady(AppDestinations.PRO_SCREEN_ROUTE)
                         },
                         viewModel = viewModel
                     )
@@ -226,7 +283,7 @@ fun AppNavigation(
                                 }
                             },
                             onNavigateToPro = {
-                                navController.navigate(AppDestinations.PRO_SCREEN_ROUTE)
+                                navController.navigateIfReady(AppDestinations.PRO_SCREEN_ROUTE)
                             },
                             onRenderModeChange = viewModel::setRenderMode,
                             customFonts = customFonts,
@@ -276,7 +333,7 @@ fun AppNavigation(
         composable(route = AppDestinations.PRO_SCREEN_ROUTE) {
             ProScreen(
                 viewModel = viewModel,
-                onNavigateBack = { navController.popBackStack() }
+                onNavigateBack = { navController.popBackStackIfReady() }
             )
         }
 
@@ -286,10 +343,22 @@ fun AppNavigation(
             )
         }
 
+        composable(route = AppDestinations.SUPPORT_PROJECT_SCREEN_ROUTE) {
+            SupportProjectScreen(
+                navController = navController
+            )
+        }
+
         composable(route = AppDestinations.FONTS_SCREEN_ROUTE) {
             FontsScreen(
                 viewModel = viewModel,
-                onBackClick = { navController.popBackStack() }
+                onBackClick = { navController.popBackStackIfReady() }
+            )
+        }
+
+        composable(route = AppDestinations.AI_SETTINGS_SCREEN_ROUTE) {
+            AiSettingsScreen(
+                onBackClick = { navController.popBackStackIfReady() }
             )
         }
     }

app/src/main/java/com/aryan/reader/AppUiModels.kt

@@ -0,0 +1,127 @@
+package com.aryan.reader
+
+import android.net.Uri
+import com.aryan.reader.data.RecentFileItem
+import com.aryan.reader.data.TagEntity
+import com.aryan.reader.epub.CalibreBundleResult
+import com.aryan.reader.epub.EpubBook
+import com.aryan.reader.paginatedreader.Locator
+import java.util.Date
+
+data class BannerMessage(val message: String, val isError: Boolean = false, val isPersistent: Boolean = false)
+
+data class ImportResult(
+    val internalUri: Uri,
+    val bookId: String,
+    val type: FileType,
+    val bundleResult: CalibreBundleResult? = null
+)
+
+data class UserData(
+    val uid: String,
+    val displayName: String?,
+    val photoUrl: String?,
+    val email: String?
+)
+
+data class NavigationEvent(
+    val route: String,
+    val bookId: String? = null,
+    val uri: Uri? = null
+)
+
+enum class AppThemeMode {
+    SYSTEM,
+    LIGHT,
+    DARK
+}
+
+enum class AppContrastOption(val value: Double) {
+    STANDARD(0.0),
+    MEDIUM(0.5),
+    HIGH(1.0)
+}
+
+data class CustomAppTheme(
+    val id: String,
+    val name: String,
+    val seedColor: androidx.compose.ui.graphics.Color
+)
+
+data class DeviceItem(val deviceId: String, val deviceName: String, val lastSeen: Date?)
+
+data class DeviceLimitReachedState(
+    val isLimitReached: Boolean = false,
+    val registeredDevices: List<DeviceItem> = emptyList()
+)
+
+data class ReaderScreenState(
+    val selectedPdfUri: Uri? = null,
+    val selectedBookId: String? = null,
+    val selectedEpubBook: EpubBook? = null,
+    val selectedEpubUri: Uri? = null,
+    val selectedFileType: FileType? = null,
+    val isLoading: Boolean = false,
+    val errorMessage: String? = null,
+    val contextualActionItems: Set<RecentFileItem> = emptySet(),
+    val renderMode: RenderMode = RenderMode.VERTICAL_SCROLL,
+    val sortOrder: SortOrder = SortOrder.RECENT,
+    val initialLocator: Locator? = null,
+    val initialCfi: String? = null,
+    val initialBookmarksJson: String? = null,
+    val initialHighlightsJson: String? = null,
+    val initialPageInBook: Int? = null,
+    val shelves: List<Shelf> = emptyList(),
+    val viewingShelfId: String? = null,
+    val isAddingBooksToShelf: Boolean = false,
+    val showCreateShelfDialog: Boolean = false,
+    val mainScreenStartPage: Int = 0,
+    val libraryScreenStartPage: Int = 0,
+    val showRenameShelfDialogFor: String? = null,
+    val showDeleteShelfDialogFor: String? = null,
+    val addBooksSource: AddBooksSource = AddBooksSource.UNSHELVED,
+    val booksSelectedForAdding: Set<String> = emptySet(),
+    val booksAvailableForAdding: List<RecentFileItem> = emptyList(),
+    val contextualActionShelfIds: Set<String> = emptySet(),
+    val currentUser: UserData? = null,
+    val isAuthMenuExpanded: Boolean = false,
+    val isProUser: Boolean = false,
+    val credits: Int = 0,
+    val isSyncEnabled: Boolean = false,
+    val isFolderSyncEnabled: Boolean = false,
+    val bannerMessage: BannerMessage? = null,
+    val deviceLimitState: DeviceLimitReachedState = DeviceLimitReachedState(),
+    val isReplacingDevice: Boolean = false,
+    val isRequestingDrivePermission: Boolean = false,
+    val downloadingBookIds: Set<String> = emptySet(),
+    val uploadingBookIds: Set<String> = emptySet(),
+    val syncedFolders: List<SyncedFolder> = emptyList(),
+    val lastFolderScanTime: Long? = null,
+    val hasUnreadFeedback: Boolean = false,
+    val searchQuery: String = "",
+    val isSearchActive: Boolean = false,
+    val isRefreshing: Boolean = false,
+    val reflowProgress: Float? = null,
+    val recentFiles: List<RecentFileItem> = emptyList(),
+    val allRecentFiles: List<RecentFileItem> = emptyList(),
+    val rawLibraryFiles: List<RecentFileItem> = emptyList(),
+    val pinnedHomeBookIds: Set<String> = emptySet(),
+    val pinnedLibraryBookIds: Set<String> = emptySet(),
+    val libraryFilters: LibraryFilters = LibraryFilters(),
+    val recentFilesLimit: Int = 0,
+    val isTabsEnabled: Boolean = false,
+    val openTabIds: List<String> = emptyList(),
+    val openTabs: List<RecentFileItem> = emptyList(),
+    val activeTabBookId: String? = null,
+    val showExternalFileSavePromptFor: String? = null,
+    val externalFileBehavior: String = "ASK",
+    val useStrictFileFilter: Boolean = false,
+    val appThemeMode: AppThemeMode = AppThemeMode.SYSTEM,
+    val appContrastOption: AppContrastOption = AppContrastOption.STANDARD,
+    val appTextDimFactorLight: Float = 1.0f,
+    val appTextDimFactorDark: Float = 1.0f,
+    val appSeedColor: androidx.compose.ui.graphics.Color? = null,
+    val customAppThemes: List<CustomAppTheme> = emptyList(),
+    val allTags: List<TagEntity> = emptyList(),
+    val showTagSelectionDialogFor: Set<String> = emptySet(),
+)

app/src/main/java/com/aryan/reader/FileTypeResolver.kt

@@ -0,0 +1,94 @@
+package com.aryan.reader
+
+private val codeOrDataExtensions = setOf(
+    "csv",
+    "tsv",
+    "json",
+    "xml",
+    "log",
+    "java",
+    "kt",
+    "py",
+    "js",
+    "cpp",
+    "c",
+    "cs",
+    "rb",
+    "go"
+)
+
+internal fun resolveFileTypeFromName(fileName: String?): FileType? {
+    val lowerName = fileName?.lowercase()?.takeIf { it.isNotBlank() } ?: return null
+    val effectiveName = lowerName.withTransparentTextSuffix()
+
+    return when {
+        effectiveName.endsWith(".cbz") -> FileType.CBZ
+        effectiveName.endsWith(".cbr") -> FileType.CBR
+        effectiveName.endsWith(".cb7") -> FileType.CB7
+        effectiveName.endsWith(".pdf") -> FileType.PDF
+        effectiveName.endsWith(".epub") -> FileType.EPUB
+        effectiveName.endsWith(".mobi") || effectiveName.endsWith(".azw3") || effectiveName.endsWith(".prc") -> FileType.MOBI
+        effectiveName.endsWith(".fb2") || effectiveName.endsWith(".fb2.zip") -> FileType.FB2
+        effectiveName.endsWith(".md") || effectiveName.endsWith(".markdown") -> FileType.MD
+        effectiveName.endsWith(".html") || effectiveName.endsWith(".xhtml") || effectiveName.endsWith(".htm") -> FileType.HTML
+        effectiveName.endsWith(".docx") -> FileType.DOCX
+        effectiveName.endsWith(".odt") -> FileType.ODT
+        effectiveName.endsWith(".fodt") -> FileType.FODT
+        effectiveName.extensionAfterLastDot() in codeOrDataExtensions -> FileType.HTML
+        effectiveName.endsWith(".txt") -> FileType.TXT
+        else -> null
+    }
+}
+
+internal fun isCodeOrDataFileName(fileName: String): Boolean {
+    return fileName.lowercase().withTransparentTextSuffix().extensionAfterLastDot() in codeOrDataExtensions
+}
+
+internal fun resolveFileExtensionSuffixFromName(fileName: String?): String? {
+    val lowerName = fileName?.lowercase()?.takeIf { it.isNotBlank() } ?: return null
+    val effectiveName = lowerName.withTransparentTextSuffix()
+    val effectiveSuffix = when {
+        effectiveName.endsWith(".fb2.zip") -> ".fb2.zip"
+        effectiveName.endsWith(".markdown") -> ".markdown"
+        effectiveName.endsWith(".xhtml") -> ".xhtml"
+        effectiveName.extensionAfterLastDot() != null && resolveFileTypeFromName(effectiveName) != null -> ".${effectiveName.extensionAfterLastDot()}"
+        else -> null
+    } ?: return null
+
+    return if (effectiveName != lowerName && lowerName.endsWith(".txt")) {
+        "$effectiveSuffix.txt"
+    } else {
+        effectiveSuffix
+    }
+}
+
+private fun String.withTransparentTextSuffix(): String {
+    if (!endsWith(".txt")) return this
+    val innerName = removeSuffix(".txt")
+    if (innerName.isBlank() || !innerName.contains('.')) return this
+    return if (resolveFileTypeFromNameWithoutTransparentText(innerName) != null) innerName else this
+}
+
+private fun resolveFileTypeFromNameWithoutTransparentText(fileName: String): FileType? {
+    return when {
+        fileName.endsWith(".cbz") -> FileType.CBZ
+        fileName.endsWith(".cbr") -> FileType.CBR
+        fileName.endsWith(".cb7") -> FileType.CB7
+        fileName.endsWith(".pdf") -> FileType.PDF
+        fileName.endsWith(".epub") -> FileType.EPUB
+        fileName.endsWith(".mobi") || fileName.endsWith(".azw3") || fileName.endsWith(".prc") -> FileType.MOBI
+        fileName.endsWith(".fb2") || fileName.endsWith(".fb2.zip") -> FileType.FB2
+        fileName.endsWith(".md") || fileName.endsWith(".markdown") -> FileType.MD
+        fileName.endsWith(".html") || fileName.endsWith(".xhtml") || fileName.endsWith(".htm") -> FileType.HTML
+        fileName.endsWith(".docx") -> FileType.DOCX
+        fileName.endsWith(".odt") -> FileType.ODT
+        fileName.endsWith(".fodt") -> FileType.FODT
+        fileName.extensionAfterLastDot() in codeOrDataExtensions -> FileType.HTML
+        else -> null
+    }
+}
+
+private fun String.extensionAfterLastDot(): String? {
+    val dotIndex = lastIndexOf('.')
+    return if (dotIndex in 0..<lastIndex) substring(dotIndex + 1) else null
+}

app/src/main/java/com/aryan/reader/FolderSyncWorker.kt

@@ -24,11 +24,11 @@ import android.content.Context
 import timber.log.Timber
 import androidx.core.net.toUri
 import androidx.documentfile.provider.DocumentFile
-import androidx.work.OneTimeWorkRequestBuilder
-import androidx.work.ExistingWorkPolicy
-import androidx.work.WorkManager
 import androidx.work.CoroutineWorker
+import androidx.work.ExistingWorkPolicy
+import androidx.work.OneTimeWorkRequestBuilder
 import androidx.work.WorkerParameters
+import androidx.work.WorkManager
 import com.aryan.reader.data.RecentFileItem
 import com.aryan.reader.data.RecentFilesRepository
 import kotlinx.coroutines.Dispatchers
@@ -53,11 +53,15 @@ class FolderSyncWorker(
         const val WORK_NAME = "FolderSyncWorker"
         const val WORK_NAME_ONETIME = "FolderSyncWorker_OneTime"
         const val KEY_METADATA_ONLY = "key_metadata_only"
+        const val KEY_TARGET_FOLDER_URI = "key_target_folder_uri"
+        private const val SCAN_DB_BATCH_SIZE = 600
         private val syncMutex = Mutex()
     }
 
     override suspend fun doWork(): Result {
+        val workerStart = ReaderPerfLog.nowNanos()
         val isMetadataOnly = inputData.getBoolean(KEY_METADATA_ONLY, false)
+        val targetFolderUri = inputData.getString(KEY_TARGET_FOLDER_URI)
         val prefs = appContext.getSharedPreferences("reader_user_prefs", Context.MODE_PRIVATE)
 
         val jsonString = prefs.getString("synced_folders_list_json", null)
@@ -87,17 +91,31 @@ class FolderSyncWorker(
         }
 
         if (folders.isEmpty()) {
-            Timber.tag("FolderSync").w("Worker: No folders linked. Aborting.")
+            ReaderPerfLog.w("FolderSync worker aborted: no linked folders")
             return Result.success()
         }
 
-        Timber.tag("FolderSync").d("Worker: processing ${folders.size} folders.")
+        val foldersToProcess = if (targetFolderUri.isNullOrBlank()) {
+            folders
+        } else {
+            folders.filter { it.first == targetFolderUri }
+        }
+
+        if (foldersToProcess.isEmpty()) {
+            ReaderPerfLog.w("FolderSync worker aborted: target folder not linked target=$targetFolderUri")
+            return Result.success()
+        }
+
+        ReaderPerfLog.d(
+            "FolderSync worker start folders=${foldersToProcess.size}/${folders.size} " +
+                "target=${targetFolderUri ?: "ALL"} metadataOnly=$isMetadataOnly"
+        )
 
         return withContext(Dispatchers.IO) {
             syncMutex.withLock {
                 var allSuccess = true
 
-                for ((uriString, allowedTypes) in folders) {
+                for ((uriString, allowedTypes) in foldersToProcess) {
                     val success = performSyncForFolder(uriString, allowedTypes, isMetadataOnly)
                     if (!success) allSuccess = false
                 }
@@ -107,12 +125,21 @@ class FolderSyncWorker(
                         val array = org.json.JSONArray(jsonString)
                         val now = System.currentTimeMillis()
                         for (i in 0 until array.length()) {
-                            array.getJSONObject(i).put("lastScanTime", now)
+                            val obj = array.getJSONObject(i)
+                            if (targetFolderUri.isNullOrBlank() || obj.optString("uri") == targetFolderUri) {
+                                obj.put("lastScanTime", now)
+                            }
                         }
                         prefs.edit { putString("synced_folders_list_json", array.toString()) }
                     } catch (_: Exception) {}
                 }
 
+                val elapsed = ReaderPerfLog.elapsedMs(workerStart)
+                ReaderPerfLog.i(
+                    "FolderSync worker finished status=${if (allSuccess) "success" else "failure"} " +
+                        "folders=${foldersToProcess.size} elapsed=${elapsed}ms"
+                )
+
                 if (allSuccess) Result.success() else Result.failure()
             }
         }
@@ -121,8 +148,24 @@ class FolderSyncWorker(
     private suspend fun performSyncForFolder(folderUriString: String, allowedFileTypes: Set<FileType>, metadataOnly: Boolean): Boolean {
         if (folderUriString.isBlank()) return true
         val folderUri = folderUriString.toUri()
+        val folderStart = ReaderPerfLog.nowNanos()
+        var dirsScanned = 0
+        var filesSeen = 0
+        var supportedBooksSeen = 0
+        var newBooks = 0
+        var updatedBooks = 0
+        var unchangedBooks = 0
+        var dbFlushes = 0
+        var scanDbFlushes = 0
+        var sidecarsImported = 0
+        var stoppedForUnlinkedFolder = false
 
         try {
+            if (!isFolderStillLinked(folderUriString)) {
+                ReaderPerfLog.w("FolderSync folder skipped: no longer linked folder=$folderUriString")
+                return true
+            }
+
             try {
                 appContext.contentResolver.takePersistableUriPermission(
                     folderUri,
@@ -137,17 +180,31 @@ class FolderSyncWorker(
                 return false
             }
 
-            Timber.tag("FolderSync").d("Phase 0: Migrating legacy root sidecars to subfolder...")
-            LocalSyncUtils.migrateLegacySidecarsToSubfolder(appContext, documentTree)
+            ReaderPerfLog.d("FolderSync phase legacy-sidecar-migration skipped")
 
-            Timber.tag("FolderSync").d("Phase 1: Importing JSON metadata from folder...")
-            val folderMetadataMap = LocalSyncUtils.getAllFolderMetadata(appContext, folderUri).toMutableMap()
+            val folderMetadataMap = ReaderPerfLog.measureSuspend(
+                name = "FolderSync phase metadata-sidecars",
+                minLogMs = 25L,
+                details = { "metadataOnly=$metadataOnly" }
+            ) {
+                LocalSyncUtils.getAllFolderMetadata(appContext, folderUri).toMutableMap()
+            }
+            ReaderPerfLog.d(
+                "FolderSync metadata-sidecars records=${folderMetadataMap.size} metadataOnly=$metadataOnly folder=$folderUriString"
+            )
 
-            Timber.tag("FolderSync").d("Phase 1.5: Preloading annotation sidecars...")
-            val preloadedSidecars = LocalSyncUtils.preloadAnnotationSidecars(appContext, documentTree).toMutableMap()
+            val preloadedSidecars = mutableMapOf<String, Pair<Long, String>>()
+            val existingFolderBooks = ReaderPerfLog.measureSuspend(
+                name = "FolderSync phase load-existing-db",
+                minLogMs = 25L
+            ) {
+                recentFilesRepository.getFilesBySourceFolder(folderUriString)
+            }
+            val existingFolderBooksById = existingFolderBooks.associateBy { it.bookId }
+            val remoteMetadataUpdates = mutableListOf<RecentFileItem>()
 
             folderMetadataMap.forEach { (bookId, remoteMeta) ->
-                val existingItem = recentFilesRepository.getFileByBookId(bookId)
+                val existingItem = existingFolderBooksById[bookId]
 
                 if (existingItem != null) {
                     if (remoteMeta.lastModifiedTimestamp > existingItem.lastModifiedTimestamp) {
@@ -166,40 +223,28 @@ class FolderSyncWorker(
                             isRecent = remoteMeta.isRecent || existingItem.isRecent,
                             timestamp = if (remoteMeta.isRecent) remoteMeta.lastModifiedTimestamp else existingItem.timestamp
                         )
-                        recentFilesRepository.addRecentFile(itemToUpdate)
+                        remoteMetadataUpdates.add(itemToUpdate)
                     } else {
                         Timber.tag("PdfPositionDebug").d("FolderSyncWorker: Local meta is newer/equal for $bookId. Ignoring remote. Local Page: ${existingItem.lastPage}")
                     }
                 }
             }
 
-            Timber.tag("FolderAnnotationSync").d("Phase 1.5: Checking annotation sidecars for existing local books...")
-            val processedBookIds = mutableSetOf<String>()
-            val existingFolderBooks = recentFilesRepository.getFilesBySourceFolder(folderUriString)
+            if (remoteMetadataUpdates.isNotEmpty()) {
+                recentFilesRepository.addRecentFiles(remoteMetadataUpdates)
+                dbFlushes++
+                ReaderPerfLog.d(
+                    "FolderSync applied remote metadata updates count=${remoteMetadataUpdates.size} folder=$folderUriString"
+                )
+            }
 
-            for (book in existingFolderBooks) {
-                processedBookIds.add(book.bookId)
-
-                val sidecarData = preloadedSidecars[book.bookId]
-
-                if (sidecarData != null) {
-                    val (remoteTs, jsonPayload) = sidecarData
-
-                    val localFiles = listOf(
-                        File(appContext.filesDir, "annotations/annotation_${book.bookId}.json"),
-                        File(appContext.filesDir, "pdf_rich_text/text_${book.bookId}.json"),
-                        File(appContext.filesDir, "page_layouts/layout_${book.bookId}.json"),
-                        File(appContext.filesDir, "pdf_text_boxes/boxes_${book.bookId}.json")
-                    )
-                    val localTs = localFiles.maxOfOrNull { if (it.exists()) it.lastModified() else 0L } ?: 0L
-
-                    if (remoteTs > (localTs + 1000)) {
-                        Timber.tag("FolderAnnotationSync").i(">>> Newer sidecar found for ${book.displayName}. Importing.")
-                        recentFilesRepository.importAnnotationBundle(book.bookId, jsonPayload)
-                    } else {
-                        Timber.tag("FolderAnnotationSync").v("Sidecar for ${book.displayName} is not newer. Skipping.")
-                    }
-                }
+            if (metadataOnly) {
+                sidecarsImported += importAnnotationSidecarsForBooks(
+                    folderUri = folderUri,
+                    folderUriString = folderUriString,
+                    books = existingFolderBooks,
+                    phase = "metadata-only"
+                )
             }
 
             if (!metadataOnly) {
@@ -207,7 +252,17 @@ class FolderSyncWorker(
                 val contentResolver = appContext.contentResolver
                 val foundBookIds = mutableSetOf<String>()
                 val newOrUpdatedItems = mutableListOf<RecentFileItem>()
-                val existingItemsMap = existingFolderBooks.associateBy { it.bookId }.toMutableMap()
+                val existingItemsMap = existingFolderBooksById.toMutableMap()
+                val existingItemsByUri = existingFolderBooks
+                    .mapNotNull { item -> item.uriString?.let { uri -> uri to item } }
+                    .toMap()
+                val legacyItemsByName = existingFolderBooks
+                    .asSequence()
+                    .filter { it.bookId.startsWith("local_${it.displayName}_") }
+                    .groupBy { it.displayName }
+                    .mapValues { entry ->
+                        ArrayDeque<RecentFileItem>().apply { addAll(entry.value) }
+                    }
 
                 val rootDocId = DocumentsContract.getTreeDocumentId(folderUri)
                 val dirQueue = ArrayDeque<String>()
@@ -223,7 +278,13 @@ class FolderSyncWorker(
 
                 while (dirQueue.isNotEmpty()) {
                     if (isStopped) break
+                    if (!isFolderStillLinked(folderUriString)) {
+                        ReaderPerfLog.w("FolderSync folder abort: folder unlinked during scan folder=$folderUriString")
+                        stoppedForUnlinkedFolder = true
+                        break
+                    }
                     val currentDocId = dirQueue.removeFirst()
+                    dirsScanned++
                     val childrenUri = DocumentsContract.buildChildDocumentsUriUsingTree(folderUri, currentDocId)
 
                     try {
@@ -234,10 +295,17 @@ class FolderSyncWorker(
                             val sizeCol = cursor.getColumnIndexOrThrow(DocumentsContract.Document.COLUMN_SIZE)
                             val modCol = cursor.getColumnIndexOrThrow(DocumentsContract.Document.COLUMN_LAST_MODIFIED)
 
-                            while (cursor.moveToNext() && !isStopped) {
+                            while (cursor.moveToNext() && !isStopped && !stoppedForUnlinkedFolder) {
                                 val docId = cursor.getString(idCol)
                                 val name = cursor.getString(nameCol) ?: ""
                                 val mimeType = cursor.getString(mimeCol)
+                                filesSeen++
+
+                                if (filesSeen % 100 == 0 && !isFolderStillLinked(folderUriString)) {
+                                    ReaderPerfLog.w("FolderSync folder abort: folder unlinked after entries=$filesSeen folder=$folderUriString")
+                                    stoppedForUnlinkedFolder = true
+                                    break
+                                }
 
                                 if (mimeType == DocumentsContract.Document.MIME_TYPE_DIR) {
                                     if (!name.startsWith(".") && name != "EpistemeSyncData") {
@@ -249,13 +317,15 @@ class FolderSyncWorker(
 
                                     val type = getFileType(name, mimeType)
                                     if (type != null && type in allowedFileTypes && !name.endsWith(".json") && !name.startsWith(".")) {
+                                        supportedBooksSeen++
                                         val stableId = buildStableBookId(name, rootDocId, docId)
                                         foundBookIds.add(stableId)
 
                                         val docUri = DocumentsContract.buildDocumentUriUsingTree(folderUri, docId)
+                                        val docUriString = docUri.toString()
                                         var existingItem = existingItemsMap[stableId]
 
-                                        if (existingItem != null && existingItem.uriString != docUri.toString()) {
+                                        if (existingItem != null && existingItem.uriString != docUriString) {
                                             val collidedItem = existingItem
                                             val collidedStableId = computeStableIdForStoredItem(collidedItem, rootDocId)
                                             if (!collidedStableId.isNullOrBlank() && collidedStableId != stableId && collidedStableId != collidedItem.bookId) {
@@ -273,12 +343,10 @@ class FolderSyncWorker(
                                         }
 
                                         if (existingItem == null) {
-                                            val oldItem = existingItemsMap.values.find {
-                                                it.bookId != stableId && (
-                                                    it.uriString == docUri.toString() ||
-                                                        it.bookId.startsWith("local_${name}_")
-                                                    )
-                                            }
+                                            val oldItem = existingItemsByUri[docUriString]?.takeIf { it.bookId != stableId }
+                                                ?: legacyItemsByName[name]?.firstOrNull {
+                                                    it.bookId != stableId
+                                                }
                                             if (oldItem != null) {
                                                 val oldId = oldItem.bookId
                                                 Timber.tag("FolderSync").i("Migrating book ID for $name from $oldId to $stableId")
@@ -291,6 +359,7 @@ class FolderSyncWorker(
                                                     preloadedSidecars = preloadedSidecars,
                                                     existingItemsMap = existingItemsMap
                                                 )
+                                                legacyItemsByName[name]?.remove(oldItem)
                                                 existingItem = existingItemsMap[stableId]
                                             }
                                         }
@@ -324,6 +393,7 @@ class FolderSyncWorker(
                                                 fileSize = size
                                             )
                                             newOrUpdatedItems.add(newItem)
+                                            newBooks++
                                         } else {
                                             var needsUpdate = false
                                             var updatedItem = existingItem
@@ -331,7 +401,11 @@ class FolderSyncWorker(
                                             if (existingItem.fileSize > 0L && size > 0L && existingItem.fileSize != size) {
                                                 Timber.tag("FolderSync").i("File size changed for $name (${existingItem.fileSize} -> $size).")
                                                 recentFilesRepository.clearLocalCachesForBook(stableId)
-                                                updatedItem = updatedItem.copy(fileSize = size, lastModifiedTimestamp = lastModified)
+                                                updatedItem = updatedItem.copy(
+                                                    fileSize = size,
+                                                    lastModifiedTimestamp = lastModified,
+                                                    folderTextMetadataParsed = false
+                                                )
                                                 needsUpdate = true
                                             }
 
@@ -347,32 +421,26 @@ class FolderSyncWorker(
 
                                             if (needsUpdate) {
                                                 newOrUpdatedItems.add(updatedItem)
+                                                updatedBooks++
+                                            } else {
+                                                unchangedBooks++
                                             }
                                         }
 
-                                        if (newOrUpdatedItems.size >= 50) {
+                                        val batchLimit = if (scanDbFlushes == 0) 40 else SCAN_DB_BATCH_SIZE
+                                        if (newOrUpdatedItems.size >= batchLimit) {
+                                            if (!isFolderStillLinked(folderUriString)) {
+                                                ReaderPerfLog.w("FolderSync batch dropped: folder unlinked pending=${newOrUpdatedItems.size} folder=$folderUriString")
+                                                newOrUpdatedItems.clear()
+                                                stoppedForUnlinkedFolder = true
+                                                break
+                                            }
                                             recentFilesRepository.addRecentFiles(newOrUpdatedItems)
+                                            dbFlushes++
+                                            scanDbFlushes++
                                             newOrUpdatedItems.clear()
                                         }
 
-                                        if (!processedBookIds.contains(stableId)) {
-                                            val sidecarData = preloadedSidecars[stableId]
-                                            if (sidecarData != null) {
-                                                val (remoteTs, jsonPayload) = sidecarData
-                                                val localFiles = listOf(
-                                                    File(appContext.filesDir, "annotations/annotation_$stableId.json"),
-                                                    File(appContext.filesDir, "pdf_rich_text/text_$stableId.json"),
-                                                    File(appContext.filesDir, "page_layouts/layout_$stableId.json"),
-                                                    File(appContext.filesDir, "pdf_text_boxes/boxes_$stableId.json")
-                                                )
-                                                val localTs = localFiles.maxOfOrNull { if (it.exists()) it.lastModified() else 0L } ?: 0L
-
-                                                if (remoteTs > (localTs + 1000)) {
-                                                    Timber.tag("FolderAnnotationSync").i(">>> Newer sidecar found for new book $stableId. Importing.")
-                                                    recentFilesRepository.importAnnotationBundle(stableId, jsonPayload)
-                                                }
-                                            }
-                                        }
                                     }
                                 }
                             }
@@ -380,16 +448,19 @@ class FolderSyncWorker(
                     } catch (e: Exception) {
                         Timber.tag("FolderSync").e(e, "Failed to query children for docId: $currentDocId")
                     }
+
+                    if (stoppedForUnlinkedFolder) break
                 }
 
-                if (newOrUpdatedItems.isNotEmpty()) {
+                if (!stoppedForUnlinkedFolder && newOrUpdatedItems.isNotEmpty()) {
                     recentFilesRepository.addRecentFiles(newOrUpdatedItems)
+                    dbFlushes++
+                    scanDbFlushes++
                     newOrUpdatedItems.clear()
                 }
 
-                if (!isStopped) {
-                    val dbFolderBooks = recentFilesRepository.getFilesBySourceFolder(folderUriString)
-                    val idsToRemove = dbFolderBooks.filter { !foundBookIds.contains(it.bookId) }.map { it.bookId }
+                if (!isStopped && !stoppedForUnlinkedFolder) {
+                    val idsToRemove = existingItemsMap.keys.filter { it !in foundBookIds }
 
                     if (idsToRemove.isNotEmpty()) {
                         Timber.tag("FolderSync").i("Cleaning up ${idsToRemove.size} missing folder books.")
@@ -398,16 +469,50 @@ class FolderSyncWorker(
                 }
             }
 
-            if (!isStopped) {
-                Timber.tag("FolderSync").i("Folder scan complete. Enqueuing metadata extraction.")
-                val metaRequest = OneTimeWorkRequestBuilder<MetadataExtractionWorker>().build()
-                WorkManager.getInstance(appContext).enqueueUniqueWork(
-                    MetadataExtractionWorker.WORK_NAME,
-                    ExistingWorkPolicy.APPEND_OR_REPLACE,
-                    metaRequest
+            if (!metadataOnly && !isStopped && !stoppedForUnlinkedFolder) {
+                val booksForAnnotationSync = ReaderPerfLog.measureSuspend(
+                    name = "FolderSync phase load-post-scan-db",
+                    minLogMs = 25L
+                ) {
+                    recentFilesRepository.getFilesBySourceFolder(folderUriString)
+                }
+                sidecarsImported += importAnnotationSidecarsForBooks(
+                    folderUri = folderUri,
+                    folderUriString = folderUriString,
+                    books = booksForAnnotationSync,
+                    phase = "post-scan"
                 )
             }
 
+            val elapsed = ReaderPerfLog.elapsedMs(folderStart)
+            ReaderPerfLog.i(
+                "FolderSync folder finished metadataOnly=$metadataOnly elapsed=${elapsed}ms " +
+                    "dirs=$dirsScanned entries=$filesSeen supported=$supportedBooksSeen " +
+                    "new=$newBooks updated=$updatedBooks unchanged=$unchangedBooks " +
+                    "dbFlushes=$dbFlushes sidecarsImported=$sidecarsImported " +
+                    "unlinkedAbort=$stoppedForUnlinkedFolder folder=$folderUriString"
+            )
+
+            if (!isStopped && !stoppedForUnlinkedFolder && !metadataOnly) {
+                if (recentFilesRepository.hasFolderBooksNeedingTextMetadata(folderUriString)) {
+                    ReaderPerfLog.i("FolderSync enqueue text metadata extraction folder=$folderUriString")
+                    val metaRequest = OneTimeWorkRequestBuilder<MetadataExtractionWorker>()
+                        .setInputData(
+                            androidx.work.Data.Builder()
+                                .putString(MetadataExtractionWorker.KEY_SOURCE_FOLDER_URI, folderUriString)
+                                .build()
+                        )
+                        .build()
+                    WorkManager.getInstance(appContext).enqueueUniqueWork(
+                        MetadataExtractionWorker.WORK_NAME,
+                        ExistingWorkPolicy.REPLACE,
+                        metaRequest
+                    )
+                } else {
+                    ReaderPerfLog.d("FolderSync text metadata extraction skipped: no pending books folder=$folderUriString")
+                }
+            }
+
             return true
 
         } catch (e: Exception) {
@@ -416,23 +521,87 @@ class FolderSyncWorker(
         }
     }
 
+    private suspend fun importAnnotationSidecarsForBooks(
+        folderUri: android.net.Uri,
+        folderUriString: String,
+        books: List<RecentFileItem>,
+        phase: String
+    ): Int {
+        if (books.isEmpty()) {
+            ReaderPerfLog.d("FolderSync phase annotation-sidecars skipped phase=$phase reason=no-books folder=$folderUriString")
+            return 0
+        }
+
+        val preloadedSidecars = ReaderPerfLog.measureSuspend(
+            name = "FolderSync phase annotation-sidecars",
+            minLogMs = 25L,
+            details = { "phase=$phase" }
+        ) {
+            LocalSyncUtils.preloadAnnotationSidecars(appContext, folderUri)
+        }
+
+        ReaderPerfLog.d(
+            "FolderSync annotation-sidecars records=${preloadedSidecars.size} books=${books.size} phase=$phase folder=$folderUriString"
+        )
+
+        if (preloadedSidecars.isEmpty()) return 0
+
+        var imported = 0
+        Timber.tag("FolderAnnotationSync").d("Checking annotation sidecars phase=$phase for ${books.size} books...")
+        for (book in books) {
+            if (isStopped || !isFolderStillLinked(folderUriString)) break
+
+            val sidecarData = preloadedSidecars[book.bookId] ?: continue
+            val (remoteTs, jsonPayload) = sidecarData
+
+            val localFiles = listOf(
+                File(appContext.filesDir, "annotations/annotation_${book.bookId}.json"),
+                File(appContext.filesDir, "pdf_rich_text/text_${book.bookId}.json"),
+                File(appContext.filesDir, "page_layouts/layout_${book.bookId}.json"),
+                File(appContext.filesDir, "pdf_text_boxes/boxes_${book.bookId}.json")
+            )
+            val localTs = localFiles.maxOfOrNull { if (it.exists()) it.lastModified() else 0L } ?: 0L
+
+            if (remoteTs > (localTs + 1000)) {
+                Timber.tag("FolderAnnotationSync").i(">>> Newer sidecar found for ${book.displayName}. Importing.")
+                recentFilesRepository.importAnnotationBundle(book.bookId, jsonPayload)
+                imported++
+            } else {
+                Timber.tag("FolderAnnotationSync").v("Sidecar for ${book.displayName} is not newer. Skipping.")
+            }
+        }
+
+        ReaderPerfLog.i(
+            "FolderSync annotation-sidecars imported=$imported records=${preloadedSidecars.size} phase=$phase folder=$folderUriString"
+        )
+        return imported
+    }
+
+    private fun isFolderStillLinked(folderUriString: String): Boolean {
+        val prefs = appContext.getSharedPreferences("reader_user_prefs", Context.MODE_PRIVATE)
+        val jsonString = prefs.getString("synced_folders_list_json", null)
+        if (jsonString != null) {
+            return try {
+                val array = org.json.JSONArray(jsonString)
+                (0 until array.length()).any { index ->
+                    array.getJSONObject(index).optString("uri") == folderUriString
+                }
+            } catch (_: Exception) {
+                false
+            }
+        }
+        return prefs.getString("synced_folder_uri", null) == folderUriString
+    }
+
     private fun getFileType(name: String, mimeType: String?): FileType? {
-        val lowerName = name.lowercase()
-        return when {
-            mimeType == "application/pdf" || lowerName.endsWith(".pdf") -> FileType.PDF
-            mimeType == "application/epub+zip" || lowerName.endsWith(".epub") -> FileType.EPUB
-            mimeType == "application/vnd.oasis.opendocument.text" || lowerName.endsWith(".odt") -> FileType.ODT
-            mimeType == "application/x-vnd.oasis.opendocument.text-flat-xml" || lowerName.endsWith(".fodt") -> FileType.FODT
-            mimeType == "application/vnd.openxmlformats-officedocument.wordprocessingml.document" || lowerName.endsWith(".docx") -> FileType.DOCX
-            lowerName.endsWith(".mobi") || lowerName.endsWith(".azw3") || lowerName.endsWith(".prc") -> FileType.MOBI
-            lowerName.endsWith(".fb2") || lowerName.endsWith(".fb2.zip") -> FileType.FB2
-            lowerName.endsWith(".cbz") -> FileType.CBZ
-            lowerName.endsWith(".cbr") -> FileType.CBR
-            lowerName.endsWith(".cb7") -> FileType.CB7
-            lowerName.endsWith(".md") || lowerName.endsWith(".markdown") -> FileType.MD
-            lowerName.endsWith(".txt") -> FileType.TXT
-            mimeType == "text/html" || lowerName.endsWith(".html") || lowerName.endsWith(".xhtml") || lowerName.endsWith(".htm") -> FileType.HTML
-            else -> null
+        return when (mimeType) {
+            "application/pdf" -> FileType.PDF
+            "application/epub+zip" -> FileType.EPUB
+            "application/vnd.oasis.opendocument.text" -> FileType.ODT
+            "application/x-vnd.oasis.opendocument.text-flat-xml" -> FileType.FODT
+            "application/vnd.openxmlformats-officedocument.wordprocessingml.document" -> FileType.DOCX
+            "text/html", "application/xhtml+xml" -> FileType.HTML
+            else -> resolveFileTypeFromName(name)
         }
     }
 

app/src/main/java/com/aryan/reader/HomeScreen.kt

@@ -73,6 +73,7 @@ import androidx.compose.material.icons.filled.MoreVert
 import androidx.compose.material.icons.filled.PhoneAndroid
 import androidx.compose.material.icons.filled.VerifiedUser
 import androidx.compose.material.icons.outlined.AccountCircle
+import androidx.compose.material.icons.outlined.FavoriteBorder
 import androidx.compose.material3.AlertDialog
 import androidx.compose.material3.Badge
 import androidx.compose.material3.BadgedBox
@@ -134,6 +135,7 @@ import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
 import androidx.core.os.LocaleListCompat
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import androidx.media3.common.util.UnstableApi
 import androidx.navigation.NavHostController
 import coil.compose.AsyncImage
 import coil.request.ImageRequest
@@ -151,11 +153,17 @@ internal fun Context.findActivity(): Activity? = when (this) {
     else -> null
 }
 
+@UnstableApi
+@androidx.annotation.OptIn(UnstableApi::class)
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
 fun HomeScreen(
     viewModel: MainViewModel, windowSizeClass: WindowSizeClass, navController: NavHostController
 ) {
+    val compStart = remember { System.currentTimeMillis() }
+    LaunchedEffect(Unit) {
+        ReaderPerfLog.d("HomeScreen initial composition ${System.currentTimeMillis() - compStart}ms")
+    }
     val context = LocalContext.current
     val customTabUriHandler = remember { CustomTabUriHandler(context) }
     var showCloseAllTabsDialog by remember { mutableStateOf(false) }
@@ -163,14 +171,15 @@ fun HomeScreen(
 
     CompositionLocalProvider(LocalUriHandler provides customTabUriHandler) {
         val uiState by viewModel.uiState.collectAsStateWithLifecycle()
-        val recentFilesForHome = uiState.recentFiles.filter { it.isRecent }
-        val openTabs = uiState.openTabs
-        val selectedContextItems = uiState.contextualActionItems
-        val isContextualModeActive = selectedContextItems.isNotEmpty()
+        val screenModel = remember(uiState) { uiState.toHomeScreenModel() }
+        val recentFilesForHome = screenModel.recentFiles
+        val openTabs = screenModel.openTabs
+        val selectedContextItems = screenModel.selectedItems
+        val isContextualModeActive = screenModel.isContextualModeActive
         val scope = rememberCoroutineScope()
         val drawerState = rememberDrawerState(initialValue = DrawerValue.Closed)
         val snackbarHostState = remember { SnackbarHostState() }
-        val deviceLimitState = uiState.deviceLimitState
+        val deviceLimitState = screenModel.deviceLimitState
 
         var showDeleteConfirmDialog by remember { mutableStateOf(false) }
         var showClearCloudDataDialog by remember { mutableStateOf(false) }
@@ -304,6 +313,12 @@ fun HomeScreen(
                                 navController.navigate(AppDestinations.FONTS_SCREEN_ROUTE)
                             }
                         },
+                        onAiSettingsClick = {
+                            scope.launch {
+                                drawerState.close()
+                                navController.navigate(AppDestinations.AI_SETTINGS_SCREEN_ROUTE)
+                            }
+                        },
                         navController = navController,
                         onFolderSyncToggle = viewModel::setFolderSyncEnabled
                     )
@@ -341,7 +356,10 @@ fun HomeScreen(
                                 onTestPanelDetectionClick = { viewModel.testPanelDetection(context) },
                                 onTestSpeechBubbleDetectionClick = { viewModel.testSpeechBubbleDetection(context) },
                                 onLanguageClick = { showLanguageDialog = true },
-                                onExportLogsClick = { viewModel.exportLogsToFile(context) }
+                                onExportLogsClick = { viewModel.exportLogsToFile(context) },
+                                onToggleHideReaderAi = {
+                                    saveHideReaderAiFeatures(context, !loadHideReaderAiFeatures(context))
+                                }
                             )
                         } else {
                             ContextualTopAppBar(
@@ -367,8 +385,8 @@ fun HomeScreen(
                                 .fillMaxSize()
                                 .padding(paddingValues)
                         ) {
-                            if (recentFilesForHome.isEmpty() && (!uiState.isTabsEnabled || openTabs.isEmpty())) {
-                                if (uiState.recentFiles.isEmpty()) {
+                            if (screenModel.isEmpty) {
+                                if (screenModel.isLibraryEmpty) {
                                     EmptyState(
                                         title = stringResource(R.string.your_library_empty),
                                         message = stringResource(R.string.your_library_empty_desc),
@@ -528,7 +546,8 @@ fun HomeScreen(
                             uiState = uiState,
                             onThemeModeChanged = viewModel::setAppThemeMode,
                             onContrastOptionChanged = viewModel::setAppContrastOption,
-                            onTextDimFactorChanged = viewModel::setAppTextDimFactor,
+                            onTextDimFactorLightChanged = viewModel::setAppTextDimFactorLight,
+                            onTextDimFactorDarkChanged = viewModel::setAppTextDimFactorDark,
                             onSeedColorChanged = viewModel::setAppSeedColor,
                             onCustomThemeAdded = viewModel::addCustomAppTheme,
                             onCustomThemeDeleted = viewModel::deleteCustomAppTheme,
@@ -596,6 +615,9 @@ private fun RecentFilesContent(
     hasSyncedFolder: Boolean
 ) {
     val canRefresh = isSyncEnabled || hasSyncedFolder
+    val selectedItemUris = remember(selectedContextItems) {
+        selectedContextItems.mapNotNullTo(mutableSetOf()) { it.uriString }
+    }
 
     val content = @Composable {
         Box(modifier = Modifier.fillMaxSize()) {
@@ -608,7 +630,7 @@ private fun RecentFilesContent(
                 isTabsEnabled = isTabsEnabled,
                 onTabCloseClick = onTabCloseClick,
                 onCloseAllTabsClick = onCloseAllTabsClick,
-                selectedItemUris = selectedContextItems.mapNotNull { it.uriString }.toSet(),
+                selectedItemUris = selectedItemUris,
                 pinnedHomeBookIds = pinnedHomeBookIds,
                 onItemClick = onItemClick,
                 onItemLongClick = onItemLongClick,
@@ -996,10 +1018,13 @@ fun DefaultTopAppBar(
     onTestPanelDetectionClick: () -> Unit,
     onTestSpeechBubbleDetectionClick: () -> Unit,
     onLanguageClick: () -> Unit,
-    onExportLogsClick: () -> Unit
+    onExportLogsClick: () -> Unit,
+    onToggleHideReaderAi: () -> Unit
 ) {
     var showOptionsMenu by remember { mutableStateOf(false) }
     var showLimitMenu by remember { mutableStateOf(false) }
+    val context = LocalContext.current
+    var hideReaderAiFeatures by remember { mutableStateOf(loadHideReaderAiFeatures(context)) }
 
     CustomTopAppBar(title = { }, navigationIcon = {
         IconButton(onClick = onDrawerClick) {
@@ -1086,6 +1111,20 @@ fun DefaultTopAppBar(
                     showOptionsMenu = false
                 })
 
+                DropdownMenuItem(
+                    text = { Text(if (hideReaderAiFeatures) "Show AI in reader" else "Hide AI in reader") },
+                    onClick = {
+                        onToggleHideReaderAi()
+                        hideReaderAiFeatures = !hideReaderAiFeatures
+                        showOptionsMenu = false
+                    },
+                    trailingIcon = {
+                        if (hideReaderAiFeatures) {
+                            Icon(Icons.Default.Check, contentDescription = stringResource(R.string.content_desc_enabled))
+                        }
+                    }
+                )
+
                 HorizontalDivider()
                 DropdownMenuItem(text = { Text(stringResource(R.string.options_clear_book_cache)) }, onClick = {
                     onClearCache()
@@ -1141,6 +1180,7 @@ private fun AppDrawerContent(
     onUpgradeClick: () -> Unit,
     onSyncUpsellClick: () -> Unit,
     onFontsClick: () -> Unit,
+    onAiSettingsClick: () -> Unit,
     navController: NavHostController,
     onFolderSyncToggle: (Boolean) -> Unit
 ) {
@@ -1311,6 +1351,26 @@ private fun AppDrawerContent(
                 modifier = Modifier.padding(horizontal = 12.dp, vertical = 4.dp)
             )
 
+            if (isOss && !BuildConfig.IS_OFFLINE) {
+                NavigationDrawerItem(
+                    icon = { Icon(painterResource(id = R.drawable.ai), contentDescription = null) },
+                    label = { Text("AI keys and models") },
+                    selected = false,
+                    onClick = onAiSettingsClick,
+                    modifier = Modifier.padding(horizontal = 12.dp, vertical = 4.dp)
+                )
+            }
+
+            if (isOss) {
+                NavigationDrawerItem(
+                    icon = { Icon(Icons.Outlined.FavoriteBorder, contentDescription = null) },
+                    label = { Text(stringResource(R.string.drawer_support_project)) },
+                    selected = false,
+                    onClick = { navController.navigate(AppDestinations.SUPPORT_PROJECT_SCREEN_ROUTE) },
+                    modifier = Modifier.padding(horizontal = 12.dp, vertical = 4.dp)
+                )
+            }
+
             NavigationDrawerItem(
                 icon = { Icon(painterResource(id = R.drawable.feedback), contentDescription = null) },
                 label = { Text(stringResource(R.string.drawer_help_feedback)) },
@@ -1692,7 +1752,8 @@ fun AppThemeBottomSheet(
     uiState: ReaderScreenState,
     onThemeModeChanged: (AppThemeMode) -> Unit,
     onContrastOptionChanged: (AppContrastOption) -> Unit,
-    onTextDimFactorChanged: (Float) -> Unit,
+    onTextDimFactorLightChanged: (Float) -> Unit,
+    onTextDimFactorDarkChanged: (Float) -> Unit,
     onSeedColorChanged: (Color?) -> Unit,
     onCustomThemeAdded: (CustomAppTheme) -> Unit,
     onCustomThemeDeleted: (String) -> Unit,
@@ -1756,24 +1817,68 @@ fun AppThemeBottomSheet(
 
             Spacer(Modifier.height(24.dp))
 
-            Text(stringResource(R.string.app_theme_text_brightness), style = MaterialTheme.typography.labelLarge, color = MaterialTheme.colorScheme.primary)
-            Spacer(Modifier.height(8.dp))
-            Row(
-                modifier = Modifier
-                    .fillMaxWidth()
-                    .height(48.dp)
-                    .background(MaterialTheme.colorScheme.surfaceContainerHigh, androidx.compose.foundation.shape.RoundedCornerShape(24.dp))
-                    .padding(horizontal = 16.dp),
-                verticalAlignment = Alignment.CenterVertically
-            ) {
-                Text("A", style = MaterialTheme.typography.titleMedium, color = MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 0.4f))
-                androidx.compose.material3.Slider(
-                    value = uiState.appTextDimFactor,
-                    onValueChange = onTextDimFactorChanged,
-                    valueRange = 0.3f..1.0f,
-                    modifier = Modifier.weight(1f).padding(horizontal = 16.dp)
-                )
-                Text("A", style = MaterialTheme.typography.titleMedium, color = MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 1.0f))
+            if (uiState.appThemeMode == AppThemeMode.SYSTEM) {
+                Text("${stringResource(R.string.app_theme_text_brightness)} (Light)", style = MaterialTheme.typography.labelLarge, color = MaterialTheme.colorScheme.primary)
+                Spacer(Modifier.height(8.dp))
+                Row(
+                    modifier = Modifier
+                        .fillMaxWidth()
+                        .height(48.dp)
+                        .background(MaterialTheme.colorScheme.surfaceContainerHigh, androidx.compose.foundation.shape.RoundedCornerShape(24.dp))
+                        .padding(horizontal = 16.dp),
+                    verticalAlignment = Alignment.CenterVertically
+                ) {
+                    Text("A", style = MaterialTheme.typography.titleMedium, color = MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 0.4f))
+                    androidx.compose.material3.Slider(
+                        value = uiState.appTextDimFactorLight,
+                        onValueChange = onTextDimFactorLightChanged,
+                        valueRange = 0.3f..1.0f,
+                        modifier = Modifier.weight(1f).padding(horizontal = 16.dp)
+                    )
+                    Text("A", style = MaterialTheme.typography.titleMedium, color = MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 1.0f))
+                }
+
+                Spacer(Modifier.height(16.dp))
+
+                Text("${stringResource(R.string.app_theme_text_brightness)} (Dark)", style = MaterialTheme.typography.labelLarge, color = MaterialTheme.colorScheme.primary)
+                Spacer(Modifier.height(8.dp))
+                Row(
+                    modifier = Modifier
+                        .fillMaxWidth()
+                        .height(48.dp)
+                        .background(MaterialTheme.colorScheme.surfaceContainerHigh, androidx.compose.foundation.shape.RoundedCornerShape(24.dp))
+                        .padding(horizontal = 16.dp),
+                    verticalAlignment = Alignment.CenterVertically
+                ) {
+                    Text("A", style = MaterialTheme.typography.titleMedium, color = MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 0.4f))
+                    androidx.compose.material3.Slider(
+                        value = uiState.appTextDimFactorDark,
+                        onValueChange = onTextDimFactorDarkChanged,
+                        valueRange = 0.3f..1.0f,
+                        modifier = Modifier.weight(1f).padding(horizontal = 16.dp)
+                    )
+                    Text("A", style = MaterialTheme.typography.titleMedium, color = MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 1.0f))
+                }
+            } else {
+                Text(stringResource(R.string.app_theme_text_brightness), style = MaterialTheme.typography.labelLarge, color = MaterialTheme.colorScheme.primary)
+                Spacer(Modifier.height(8.dp))
+                Row(
+                    modifier = Modifier
+                        .fillMaxWidth()
+                        .height(48.dp)
+                        .background(MaterialTheme.colorScheme.surfaceContainerHigh, androidx.compose.foundation.shape.RoundedCornerShape(24.dp))
+                        .padding(horizontal = 16.dp),
+                    verticalAlignment = Alignment.CenterVertically
+                ) {
+                    Text("A", style = MaterialTheme.typography.titleMedium, color = MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 0.4f))
+                    androidx.compose.material3.Slider(
+                        value = if (uiState.appThemeMode == AppThemeMode.DARK) uiState.appTextDimFactorDark else uiState.appTextDimFactorLight,
+                        onValueChange = if (uiState.appThemeMode == AppThemeMode.DARK) onTextDimFactorDarkChanged else onTextDimFactorLightChanged,
+                        valueRange = 0.3f..1.0f,
+                        modifier = Modifier.weight(1f).padding(horizontal = 16.dp)
+                    )
+                    Text("A", style = MaterialTheme.typography.titleMedium, color = MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 1.0f))
+                }
             }
 
             Spacer(Modifier.height(24.dp))

app/src/main/java/com/aryan/reader/LibraryModels.kt

@@ -0,0 +1,86 @@
+package com.aryan.reader
+
+import com.aryan.reader.data.RecentFileItem
+
+enum class AddBooksSource {
+    UNSHELVED,
+    ALL_BOOKS
+}
+
+enum class FileType {
+    PDF, EPUB, MOBI, MD, TXT, HTML, FB2, CBZ, CBR, CB7, DOCX, ODT, FODT
+}
+
+internal val PDF_VIEWER_FILE_TYPES = setOf(FileType.PDF, FileType.CBZ, FileType.CBR, FileType.CB7)
+
+internal val EPUB_READER_FILE_TYPES = setOf(
+    FileType.EPUB,
+    FileType.MOBI,
+    FileType.MD,
+    FileType.TXT,
+    FileType.HTML,
+    FileType.FB2,
+    FileType.DOCX,
+    FileType.ODT,
+    FileType.FODT
+)
+
+enum class RenderMode {
+    VERTICAL_SCROLL, PAGINATED
+}
+
+data class SyncedFolder(
+    val uriString: String,
+    val name: String,
+    val lastScanTime: Long,
+    val allowedFileTypes: Set<FileType> = FileType.entries.toSet()
+)
+
+enum class ShelfType { MANUAL, SMART, TAG, SERIES, FOLDER }
+
+data class Shelf(
+    val id: String,
+    val name: String,
+    val type: ShelfType,
+    val books: List<RecentFileItem>,
+    val directBooks: List<RecentFileItem> = books,
+    val parentShelfId: String? = null,
+    val childShelfIds: List<String> = emptyList(),
+    val depth: Int = 0,
+    val sortKey: String = name.lowercase()
+) {
+    val bookCount: Int get() = books.size
+    val topBook: RecentFileItem? by lazy(LazyThreadSafetyMode.NONE) { books.maxByOrNull { it.timestamp } }
+    val directBookCount: Int get() = directBooks.size
+    val childShelfCount: Int get() = childShelfIds.size
+}
+
+enum class SortOrder {
+    RECENT,
+    TITLE_ASC,
+    AUTHOR_ASC,
+    PERCENT_ASC,
+    PERCENT_DESC,
+    SIZE_ASC,
+    SIZE_DESC
+}
+
+enum class ReadStatusFilter {
+    ALL,
+    UNREAD,
+    IN_PROGRESS,
+    COMPLETED
+}
+
+data class LibraryFilters(
+    val fileTypes: Set<FileType> = emptySet(),
+    val sourceFolders: Set<String> = emptySet(),
+    val readStatus: ReadStatusFilter = ReadStatusFilter.ALL,
+    val tagIds: Set<String> = emptySet()
+) {
+    val isActive: Boolean
+        get() = fileTypes.isNotEmpty() ||
+            sourceFolders.isNotEmpty() ||
+            readStatus != ReadStatusFilter.ALL ||
+            tagIds.isNotEmpty()
+}

app/src/main/java/com/aryan/reader/LibraryScreen.kt

@@ -56,6 +56,7 @@ import androidx.compose.foundation.lazy.LazyRow
 import androidx.compose.foundation.lazy.items
 import androidx.compose.foundation.lazy.itemsIndexed
 import androidx.compose.foundation.pager.HorizontalPager
+import androidx.compose.foundation.pager.PagerDefaults
 import androidx.compose.foundation.pager.PagerState
 import androidx.compose.foundation.pager.rememberPagerState
 import androidx.compose.foundation.rememberScrollState
@@ -131,6 +132,7 @@ import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import androidx.lifecycle.viewmodel.compose.viewModel
+import androidx.media3.common.util.UnstableApi
 import coil.compose.AsyncImage
 import coil.request.ImageRequest
 import com.aryan.reader.data.RecentFileItem
@@ -141,6 +143,8 @@ import com.aryan.reader.opds.OpdsEntry
 import com.aryan.reader.opds.OpdsViewModel
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.distinctUntilChanged
+import kotlinx.coroutines.flow.drop
 import kotlinx.coroutines.launch
 import org.jsoup.Jsoup
 import timber.log.Timber
@@ -154,20 +158,26 @@ private fun getBookCountString(count: Int): String {
     return pluralStringResource(id = R.plurals.book_count, count, count)
 }
 
+@UnstableApi
 @SuppressLint("LocalContextGetResourceValueCall")
 @Composable
 fun LibraryScreen(
     viewModel: MainViewModel,
 ) {
+    val compStart = remember { System.currentTimeMillis() }
+    LaunchedEffect(Unit) {
+        ReaderPerfLog.d("LibraryScreen initial composition ${System.currentTimeMillis() - compStart}ms")
+    }
     val context = LocalContext.current
     val uiState by viewModel.uiState.collectAsStateWithLifecycle()
-    val selectedItems = uiState.contextualActionItems
-    val isContextualModeActive = selectedItems.isNotEmpty()
-    val selectedShelves = uiState.contextualActionShelfIds
-    val isShelfContextualModeActive = selectedShelves.isNotEmpty()
-    val sortOrder = uiState.sortOrder
-    val shelves = uiState.shelves
-    val rawLibraryFiles = uiState.rawLibraryFiles
+    val screenModel = remember(uiState) { uiState.toLibraryScreenModel() }
+    val selectedItems = screenModel.selectedItems
+    val isContextualModeActive = screenModel.isContextualModeActive
+    val selectedShelves = screenModel.selectedShelves
+    val isShelfContextualModeActive = screenModel.isShelfContextualModeActive
+    val sortOrder = screenModel.sortOrder
+    val shelves = screenModel.shelves
+    val rawLibraryFiles = screenModel.rawLibraryFiles
     val tabTitles = remember {
         buildList {
             add(context.getString(R.string.tab_all_books))
@@ -183,21 +193,13 @@ fun LibraryScreen(
         pageCount = { tabTitles.size }
     )
 
-    val containsFolderItems = remember(selectedItems) {
-        selectedItems.any { it.sourceFolderUri != null }
-    }
-
-    LaunchedEffect(uiState.libraryScreenStartPage) {
-        if (pagerState.currentPage != uiState.libraryScreenStartPage) {
-            pagerState.animateScrollToPage(uiState.libraryScreenStartPage)
-        }
-    }
+    val containsFolderItems = screenModel.containsFolderItemsInSelection
 
     val scope = rememberCoroutineScope()
     var showFilterSheet by remember { mutableStateOf(false) }
 
-    val isSearchActive = uiState.isSearchActive
-    val searchQuery = uiState.searchQuery
+    val isSearchActive = screenModel.isSearchActive
+    val searchQuery = screenModel.searchQuery
 
     val pickFolderLauncher = rememberLauncherForActivityResult(
         contract = ActivityResultContracts.OpenDocumentTree()
@@ -250,6 +252,8 @@ fun LibraryScreen(
 
     LaunchedEffect(pagerState) {
         androidx.compose.runtime.snapshotFlow { pagerState.settledPage }
+            .drop(1)
+            .distinctUntilChanged()
             .collect { page ->
                 viewModel.setLibraryScreenPage(page)
             }
@@ -401,6 +405,7 @@ fun LibraryScreen(
     }
 }
 
+@UnstableApi
 @Composable
 fun ShelfScreen(
     viewModel: MainViewModel,
@@ -577,6 +582,7 @@ fun LibraryScreenContent(
     val isShelfContextualModeActive = selectedShelves.isNotEmpty()
     var showSortMenu by remember { mutableStateOf(false) }
     val searchFocusRequester = remember { FocusRequester() }
+    val selectedBookIds = remember(selectedItems) { selectedItems.mapTo(mutableSetOf()) { it.bookId } }
 
     var textFieldValue by remember(isSearchActive) {
         mutableStateOf(TextFieldValue(searchQuery, TextRange(searchQuery.length)))
@@ -712,7 +718,16 @@ fun LibraryScreenContent(
                             Tab(
                                 selected = pagerState.currentPage == index,
                                 onClick = {
-                                    scope.launch { pagerState.animateScrollToPage(index) }
+                                    ReaderPerfLog.d("LibraryPager click page=$index title=$title")
+                                    if (pagerState.currentPage != index) {
+                                        scope.launch {
+                                            val start = ReaderPerfLog.nowNanos()
+                                            pagerState.animateScrollToPage(index)
+                                            ReaderPerfLog.d(
+                                                "LibraryPager settled page=$index elapsed=${ReaderPerfLog.elapsedMs(start)}ms"
+                                            )
+                                        }
+                                    }
                                 },
                                 text = { Text(title) }
                             )
@@ -798,6 +813,11 @@ fun LibraryScreenContent(
             modifier = Modifier
                 .fillMaxSize()
                 .padding(paddingValues),
+            flingBehavior = PagerDefaults.flingBehavior(
+                state = pagerState,
+                snapPositionalThreshold = 0.25f
+            ),
+            beyondViewportPageCount = 0,
             key = { it }
         ) { page ->
             when (page) {
@@ -822,7 +842,7 @@ fun LibraryScreenContent(
                             items(recentFiles, key = { it.bookId }) { item ->
                                 LibraryListItem(
                                     item = item,
-                                    isSelected = selectedItems.any { it.bookId == item.bookId },
+                                    isSelected = item.bookId in selectedBookIds,
                                     isPinned = item.bookId in pinnedLibraryBookIds,
                                     onItemClick = { onItemClick(item) },
                                     onItemLongClick = { onItemLongClick(item) },
@@ -1876,6 +1896,18 @@ private fun FolderSyncScreen(
     isLoading: Boolean
 ) {
     var editingFolder by remember { mutableStateOf<SyncedFolder?>(null) }
+    val folderStatsByUri = remember(allRecentFiles) {
+        allRecentFiles
+            .asSequence()
+            .filter { it.sourceFolderUri != null }
+            .groupBy { it.sourceFolderUri!! }
+            .mapValues { (_, files) ->
+                FolderFileStats(
+                    totalBooks = files.size,
+                    countsByType = files.groupingBy { it.type }.eachCount()
+                )
+            }
+    }
 
     Scaffold(
         floatingActionButton = {
@@ -1943,7 +1975,7 @@ private fun FolderSyncScreen(
                 items(syncedFolders, key = { it.uriString }) { folder ->
                     FolderCard(
                         folder = folder,
-                        allRecentFiles = allRecentFiles,
+                        stats = folderStatsByUri[folder.uriString] ?: FolderFileStats.Empty,
                         onRemoveClick = onRemoveFolderClick,
                         onEditFiltersClick = { editingFolder = folder }
                     )
@@ -1952,11 +1984,11 @@ private fun FolderSyncScreen(
         }
     }
 
-    if (editingFolder != null) {
+    editingFolder?.let { folder ->
         EditFolderFiltersDialog(
-            folder = editingFolder!!,
+            folder = folder,
             onConfirm = { newFilters ->
-                onEditFolderFiltersClick(editingFolder!!, newFilters)
+                onEditFolderFiltersClick(folder, newFilters)
                 editingFolder = null
             },
             onDismiss = { editingFolder = null }
@@ -1964,11 +1996,20 @@ private fun FolderSyncScreen(
     }
 }
 
+private data class FolderFileStats(
+    val totalBooks: Int,
+    val countsByType: Map<FileType, Int>
+) {
+    companion object {
+        val Empty = FolderFileStats(totalBooks = 0, countsByType = emptyMap())
+    }
+}
+
 @OptIn(androidx.compose.foundation.layout.ExperimentalLayoutApi::class)
 @Composable
 private fun FolderCard(
     folder: SyncedFolder,
-    allRecentFiles: List<RecentFileItem>,
+    stats: FolderFileStats,
     onRemoveClick: (SyncedFolder) -> Unit,
     onEditFiltersClick: (SyncedFolder) -> Unit
 ) {
@@ -1976,14 +2017,6 @@ private fun FolderCard(
     val dateFormat = remember { SimpleDateFormat("MMM d, h:mm a", Locale.getDefault()) }
     val lastScanText = if (folder.lastScanTime == 0L) stringResource(R.string.never) else dateFormat.format(Date(folder.lastScanTime))
 
-    val folderFiles = remember(allRecentFiles, folder.uriString) {
-        allRecentFiles.filter { it.sourceFolderUri == folder.uriString }
-    }
-    val totalBooks = folderFiles.size
-    val countsByType = remember(folderFiles) {
-        folderFiles.groupBy { it.type }.mapValues { it.value.size }
-    }
-
     androidx.compose.material3.ElevatedCard(
         modifier = Modifier.fillMaxWidth(),
         colors = androidx.compose.material3.CardDefaults.elevatedCardColors(
@@ -2058,18 +2091,18 @@ private fun FolderCard(
                         color = MaterialTheme.colorScheme.onSurfaceVariant,
                         fontWeight = FontWeight.Bold
                     )
-                    Text(text = totalBooks.toString(), style = MaterialTheme.typography.bodyMedium)
+                    Text(text = stats.totalBooks.toString(), style = MaterialTheme.typography.bodyMedium)
                 }
             }
 
-            if (countsByType.isNotEmpty()) {
+            if (stats.countsByType.isNotEmpty()) {
                 Spacer(modifier = Modifier.height(12.dp))
                 androidx.compose.foundation.layout.FlowRow(
                     horizontalArrangement = Arrangement.spacedBy(8.dp),
                     verticalArrangement = Arrangement.spacedBy(8.dp),
                     modifier = Modifier.fillMaxWidth()
                 ) {
-                    countsByType.forEach { (type, count) ->
+                    stats.countsByType.forEach { (type, count) ->
                         AssistChip(
                             onClick = { },
                             label = { Text(stringResource(R.string.folder_filter_count, type.name, count)) }

app/src/main/java/com/aryan/reader/LibraryStateProjector.kt

@@ -0,0 +1,435 @@
+package com.aryan.reader
+
+import com.aryan.reader.data.BookShelfCrossRef
+import com.aryan.reader.data.BookTagCrossRef
+import com.aryan.reader.data.RecentFileItem
+import com.aryan.reader.data.ShelfEntity
+import com.aryan.reader.data.SmartCollectionEngine
+import com.aryan.reader.data.TagEntity
+
+fun interface FolderPathResolver {
+    fun relativeFolderSegments(item: RecentFileItem): List<String>
+}
+
+object EmptyFolderPathResolver : FolderPathResolver {
+    override fun relativeFolderSegments(item: RecentFileItem): List<String> = emptyList()
+}
+
+data class LibraryProjectionInput(
+    val state: ReaderScreenState,
+    val recentFilesFromDb: List<RecentFileItem>,
+    val dbShelves: List<ShelfEntity>,
+    val shelfRefs: List<BookShelfCrossRef>,
+    val dbTags: List<TagEntity>,
+    val tagRefs: List<BookTagCrossRef>
+)
+
+class LibraryStateProjector(
+    private val folderPathResolver: FolderPathResolver = EmptyFolderPathResolver
+) {
+    private var cachedProjection: CachedProjection? = null
+
+    fun project(input: LibraryProjectionInput): ReaderScreenState {
+        val start = ReaderPerfLog.nowNanos()
+        val internalState = input.state
+        val cacheKey = ProjectionCacheKey(
+            recentFilesFromDb = input.recentFilesFromDb,
+            dbShelves = input.dbShelves,
+            shelfRefs = input.shelfRefs,
+            dbTags = input.dbTags,
+            tagRefs = input.tagRefs,
+            folderKeys = internalState.syncedFolders.map { SyncedFolderProjectionKey(it.uriString, it.name) },
+            sortOrder = internalState.sortOrder,
+            searchQuery = internalState.searchQuery,
+            libraryFilters = internalState.libraryFilters,
+            recentFilesLimit = internalState.recentFilesLimit
+        )
+
+        cachedProjection?.takeIf { it.key == cacheKey }?.let { cache ->
+            val result = buildStateFromCache(internalState, cache)
+            val elapsed = ReaderPerfLog.elapsedMs(start)
+            if (elapsed >= 8L) {
+                ReaderPerfLog.d(
+                    "LibraryProject cache-hit took ${elapsed}ms books=${cache.allLibraryFiles.size} shelves=${cache.shelfProjection.shelves.size}"
+                )
+            }
+            return result
+        }
+
+        val tagsById = input.dbTags.associateBy { it.id }
+        val bookTagsMap = input.tagRefs.groupBy { it.bookId }.mapValues { entry ->
+            entry.value.mapNotNull { tagsById[it.tagId] }
+        }
+
+        val allLibraryFiles = input.recentFilesFromDb
+            .filterNot { it.bookId.endsWith("_reflow") }
+            .map { item ->
+                item.copy(tags = bookTagsMap[item.bookId] ?: emptyList())
+            }
+        val allLibraryFilesById = allLibraryFiles.associateBy { it.bookId }
+
+        val rawFilteredByQuery = filterBySearch(allLibraryFiles, internalState.searchQuery)
+        val libraryFiltered = applyLibraryFilters(rawFilteredByQuery, internalState.libraryFilters)
+        val sortedLibraryFiles = if (internalState.sortOrder == SortOrder.RECENT) {
+            libraryFiltered
+        } else {
+            sortFiles(libraryFiltered, internalState.sortOrder)
+        }
+        val recentLimit = if (internalState.recentFilesLimit > 0) internalState.recentFilesLimit else Int.MAX_VALUE
+        val visibleRecentFiles = if (internalState.sortOrder == SortOrder.RECENT) {
+            allLibraryFiles
+                .asSequence()
+                .filter { it.isRecent }
+                .take(recentLimit)
+                .toList()
+        } else {
+            sortFiles(
+                allLibraryFiles.filter { it.isRecent },
+                internalState.sortOrder
+            ).take(recentLimit)
+        }
+
+        val shelfProjection = buildShelves(
+            allLibraryFiles = allLibraryFiles,
+            dbShelves = input.dbShelves,
+            shelfRefs = input.shelfRefs,
+            dbTags = input.dbTags,
+            sortOrder = internalState.sortOrder,
+            syncedFolders = internalState.syncedFolders
+        )
+
+        val cache = CachedProjection(
+            key = cacheKey,
+            allLibraryFiles = allLibraryFiles,
+            allLibraryFilesById = allLibraryFilesById,
+            sortedLibraryFiles = sortedLibraryFiles,
+            visibleRecentFiles = visibleRecentFiles,
+            shelfProjection = shelfProjection,
+            validShelfIds = shelfProjection.shelves.mapTo(mutableSetOf()) { it.id },
+            dbTags = input.dbTags
+        )
+        cachedProjection = cache
+
+        val elapsed = ReaderPerfLog.elapsedMs(start)
+        if (elapsed >= 16L || allLibraryFiles.size >= 500) {
+            ReaderPerfLog.d(
+                "LibraryProject recompute took ${elapsed}ms books=${allLibraryFiles.size} " +
+                    "visible=${sortedLibraryFiles.size} shelves=${shelfProjection.shelves.size} " +
+                    "tags=${input.dbTags.size} shelfRefs=${input.shelfRefs.size} tagRefs=${input.tagRefs.size}"
+            )
+        }
+
+        return buildStateFromCache(internalState, cache)
+    }
+
+    private fun buildStateFromCache(
+        internalState: ReaderScreenState,
+        cache: CachedProjection
+    ): ReaderScreenState {
+        val viewingShelfId = internalState.viewingShelfId?.takeIf { it in cache.validShelfIds }
+        val selectedShelfIds = internalState.contextualActionShelfIds.filterTo(mutableSetOf()) { it in cache.validShelfIds }
+        val booksAvailableForAdding = if (internalState.isAddingBooksToShelf && viewingShelfId != null) {
+            val currentShelfBookIds = cache.shelfProjection.shelves
+                .find { it.id == viewingShelfId }
+                ?.books
+                ?.mapTo(mutableSetOf()) { it.bookId }
+                ?: emptySet()
+            when (internalState.addBooksSource) {
+                AddBooksSource.UNSHELVED -> cache.shelfProjection.unshelvedBooks
+                AddBooksSource.ALL_BOOKS -> cache.allLibraryFiles.filter { it.bookId !in currentShelfBookIds }
+            }
+        } else {
+            emptyList()
+        }
+
+        return internalState.copy(
+            recentFiles = cache.visibleRecentFiles,
+            allRecentFiles = cache.sortedLibraryFiles,
+            rawLibraryFiles = cache.allLibraryFiles,
+            viewingShelfId = viewingShelfId,
+            isAddingBooksToShelf = internalState.isAddingBooksToShelf && viewingShelfId != null,
+            contextualActionShelfIds = selectedShelfIds,
+            contextualActionItems = internalState.contextualActionItems
+                .mapNotNull { ctx -> cache.allLibraryFilesById[ctx.bookId] }
+                .toSet(),
+            shelves = cache.shelfProjection.shelves,
+            openTabs = internalState.openTabIds.mapNotNull { tabId -> cache.allLibraryFilesById[tabId] },
+            booksAvailableForAdding = booksAvailableForAdding,
+            allTags = cache.dbTags
+        )
+    }
+
+    private fun buildShelves(
+        allLibraryFiles: List<RecentFileItem>,
+        dbShelves: List<ShelfEntity>,
+        shelfRefs: List<BookShelfCrossRef>,
+        dbTags: List<TagEntity>,
+        sortOrder: SortOrder,
+        syncedFolders: List<SyncedFolder>
+    ): ShelfProjection {
+        val allShelves = mutableListOf<Shelf>()
+        val shelvedBookIds = mutableSetOf<String>()
+        val baseFilesMap = allLibraryFiles.associateBy { it.bookId }
+        val shelfRefsByShelfId = shelfRefs.groupBy { it.shelfId }
+        val taggedBookIdsByTagId = mutableMapOf<String, MutableList<String>>()
+
+        allLibraryFiles.forEach { item ->
+            item.tags.forEach { tag ->
+                taggedBookIdsByTagId.getOrPut(tag.id) { mutableListOf() }.add(item.bookId)
+            }
+        }
+
+        dbShelves.forEach { shelfEntity ->
+            if (shelfEntity.isSmart && shelfEntity.smartRulesJson != null) {
+                val rules = SmartCollectionEngine.fromJson(shelfEntity.smartRulesJson)
+                if (rules != null) {
+                    val matchingBooks = allLibraryFiles.filter { SmartCollectionEngine.evaluate(it, rules) }
+                    allShelves.add(Shelf(shelfEntity.id, shelfEntity.name, ShelfType.SMART, sortFiles(matchingBooks, sortOrder)))
+                    shelvedBookIds.addAll(matchingBooks.map { it.bookId })
+                }
+            } else {
+                val bookIdsInShelf = shelfRefsByShelfId[shelfEntity.id].orEmpty()
+                    .sortedBy { it.addedAt }
+                    .map { it.bookId }
+                val booksInShelf = bookIdsInShelf.mapNotNull { baseFilesMap[it] }
+                allShelves.add(Shelf(shelfEntity.id, shelfEntity.name, ShelfType.MANUAL, sortFiles(booksInShelf, sortOrder)))
+                shelvedBookIds.addAll(bookIdsInShelf)
+            }
+        }
+
+        val tagShelves = dbTags.mapNotNull { tag ->
+            val taggedBooks = taggedBookIdsByTagId[tag.id].orEmpty().mapNotNull { baseFilesMap[it] }
+            if (taggedBooks.isEmpty()) {
+                null
+            } else {
+                Shelf("tag_${tag.id}", tag.name, ShelfType.TAG, sortFiles(taggedBooks, sortOrder))
+            }
+        }
+        allShelves.addAll(tagShelves)
+
+        val seriesShelves = allLibraryFiles
+            .filter { !it.seriesName.isNullOrBlank() }
+            .groupBy { it.seriesName!! }
+            .filter { it.value.size >= 2 }
+            .map { (series, books) ->
+                val sortedSeries = books.sortedBy { it.seriesIndex ?: 999.0 }
+                shelvedBookIds.addAll(books.map { it.bookId })
+                Shelf("series_$series", series, ShelfType.SERIES, sortedSeries)
+            }
+        allShelves.addAll(seriesShelves)
+
+        val folderShelves = buildFolderShelves(
+            allLibraryFiles = allLibraryFiles,
+            syncedFolders = syncedFolders,
+            sortOrder = sortOrder
+        ).also { shelves ->
+            shelves.forEach { shelf ->
+                shelvedBookIds.addAll(shelf.books.map { it.bookId })
+            }
+        }
+        allShelves.addAll(folderShelves)
+
+        val unshelvedBooks = allLibraryFiles.filter { it.bookId !in shelvedBookIds }
+        allShelves.add(Shelf("unshelved", "Unshelved", ShelfType.MANUAL, sortFiles(unshelvedBooks, sortOrder)))
+
+        allShelves.sortWith(compareBy({ it.type.ordinal }, { it.sortKey }))
+        return ShelfProjection(shelves = allShelves, unshelvedBooks = unshelvedBooks)
+    }
+
+    private fun buildFolderShelves(
+        allLibraryFiles: List<RecentFileItem>,
+        syncedFolders: List<SyncedFolder>,
+        sortOrder: SortOrder
+    ): List<Shelf> {
+        val folderNamesByUri = syncedFolders.associate { it.uriString to it.name }
+        val folderSegmentsByBookId = allLibraryFiles
+            .asSequence()
+            .filter { it.sourceFolderUri != null }
+            .associate { it.bookId to folderPathResolver.relativeFolderSegments(it) }
+
+        return allLibraryFiles
+            .filter { it.sourceFolderUri != null }
+            .groupBy { it.sourceFolderUri!! }
+            .flatMap { (folderUri, books) ->
+                val rootName = folderNamesByUri[folderUri] ?: "Local Folder"
+                val rootShelfId = "folder_$folderUri"
+                val rootAccumulator = FolderShelfAccumulator(
+                    id = rootShelfId,
+                    name = rootName,
+                    depth = 0,
+                    parentShelfId = null,
+                    sortPath = ""
+                )
+                val rootShelf = Shelf(
+                    id = rootShelfId,
+                    name = rootName,
+                    type = ShelfType.FOLDER,
+                    books = sortFiles(books, sortOrder),
+                    directBooks = emptyList(),
+                    childShelfIds = emptyList(),
+                    depth = 0,
+                    sortKey = "folder:${rootName.lowercase()}:"
+                )
+
+                val nestedShelves = linkedMapOf<String, FolderShelfAccumulator>()
+                val nestedShelvesById = mutableMapOf<String, FolderShelfAccumulator>()
+                books.forEach { book ->
+                    rootAccumulator.books.add(book)
+                    val segments = folderSegmentsByBookId[book.bookId].orEmpty()
+                    if (segments.isEmpty()) {
+                        rootAccumulator.directBooks.add(book)
+                    }
+                    var currentPath = ""
+                    var parentShelfId = rootShelfId
+                    segments.forEachIndexed { index, segment ->
+                        currentPath = if (currentPath.isEmpty()) segment else "$currentPath/$segment"
+                        val shelfId = "folder_$folderUri::$currentPath"
+                        val accumulator = nestedShelves.getOrPut(currentPath) {
+                            val newShelf = FolderShelfAccumulator(
+                                id = shelfId,
+                                name = segment,
+                                depth = index + 1,
+                                parentShelfId = parentShelfId,
+                                sortPath = currentPath.lowercase()
+                            )
+                            if (parentShelfId == rootShelfId) {
+                                rootAccumulator.childShelfIds.add(shelfId)
+                            } else {
+                                nestedShelvesById[parentShelfId]?.childShelfIds?.add(shelfId)
+                            }
+                            nestedShelvesById[shelfId] = newShelf
+                            newShelf
+                        }
+                        accumulator.books.add(book)
+                        if (index == segments.lastIndex) {
+                            accumulator.directBooks.add(book)
+                        }
+                        parentShelfId = shelfId
+                    }
+                }
+
+                val sortedNestedShelves = nestedShelves
+                    .values
+                    .sortedBy { it.sortPath }
+                    .map { shelf ->
+                        Shelf(
+                            id = shelf.id,
+                            name = shelf.name,
+                            type = ShelfType.FOLDER,
+                            books = sortFiles(shelf.books, sortOrder),
+                            directBooks = sortFiles(shelf.directBooks, sortOrder),
+                            parentShelfId = shelf.parentShelfId,
+                            childShelfIds = shelf.childShelfIds.sortedBy { it.substringAfterLast("::").lowercase() },
+                            depth = shelf.depth,
+                            sortKey = "folder:${rootName.lowercase()}:${shelf.sortPath}"
+                        )
+                    }
+
+                listOf(
+                    rootShelf.copy(
+                        directBooks = sortFiles(rootAccumulator.directBooks, sortOrder),
+                        childShelfIds = rootAccumulator.childShelfIds.sortedBy { it.substringAfterLast("::").lowercase() }
+                    )
+                ) + sortedNestedShelves
+            }
+    }
+
+    private data class FolderShelfAccumulator(
+        val id: String,
+        val name: String,
+        val depth: Int,
+        val parentShelfId: String?,
+        val sortPath: String,
+        val books: MutableList<RecentFileItem> = mutableListOf(),
+        val directBooks: MutableList<RecentFileItem> = mutableListOf(),
+        val childShelfIds: MutableList<String> = mutableListOf()
+    )
+
+    private data class ShelfProjection(
+        val shelves: List<Shelf>,
+        val unshelvedBooks: List<RecentFileItem>
+    )
+
+    private data class ProjectionCacheKey(
+        val recentFilesFromDb: List<RecentFileItem>,
+        val dbShelves: List<ShelfEntity>,
+        val shelfRefs: List<BookShelfCrossRef>,
+        val dbTags: List<TagEntity>,
+        val tagRefs: List<BookTagCrossRef>,
+        val folderKeys: List<SyncedFolderProjectionKey>,
+        val sortOrder: SortOrder,
+        val searchQuery: String,
+        val libraryFilters: LibraryFilters,
+        val recentFilesLimit: Int
+    )
+
+    private data class SyncedFolderProjectionKey(
+        val uriString: String,
+        val name: String
+    )
+
+    private data class CachedProjection(
+        val key: ProjectionCacheKey,
+        val allLibraryFiles: List<RecentFileItem>,
+        val allLibraryFilesById: Map<String, RecentFileItem>,
+        val sortedLibraryFiles: List<RecentFileItem>,
+        val visibleRecentFiles: List<RecentFileItem>,
+        val shelfProjection: ShelfProjection,
+        val validShelfIds: Set<String>,
+        val dbTags: List<TagEntity>
+    )
+}
+
+fun filterBySearch(files: List<RecentFileItem>, searchQuery: String): List<RecentFileItem> {
+    val query = searchQuery.trim()
+    return if (query.isBlank()) {
+        files
+    } else {
+        files.filter { item ->
+            item.displayName.contains(query, ignoreCase = true) ||
+                item.title?.contains(query, ignoreCase = true) == true ||
+                item.author?.contains(query, ignoreCase = true) == true ||
+                item.tags.any { tag -> tag.name.contains(query, ignoreCase = true) }
+        }
+    }
+}
+
+fun applyLibraryFilters(files: List<RecentFileItem>, filters: LibraryFilters): List<RecentFileItem> {
+    return files.filter { item ->
+        val matchType = if (filters.fileTypes.isNotEmpty()) item.type in filters.fileTypes else true
+        val matchFolder = if (filters.sourceFolders.isNotEmpty()) {
+            val matchesInApp = filters.sourceFolders.contains("IN_APP_STORAGE") &&
+                item.sourceFolderUri == null &&
+                item.uriString?.startsWith("opds-pse") != true
+            val matchesSynced = item.sourceFolderUri in filters.sourceFolders
+            matchesInApp || matchesSynced
+        } else {
+            true
+        }
+        val progress = item.progressPercentage ?: 0f
+        val matchStatus = when (filters.readStatus) {
+            ReadStatusFilter.ALL -> true
+            ReadStatusFilter.UNREAD -> progress == 0f
+            ReadStatusFilter.IN_PROGRESS -> progress > 0f && progress < 100f
+            ReadStatusFilter.COMPLETED -> progress >= 100f
+        }
+        val matchTags = if (filters.tagIds.isNotEmpty()) {
+            item.tags.any { it.id in filters.tagIds }
+        } else {
+            true
+        }
+        matchType && matchFolder && matchStatus && matchTags
+    }
+}
+
+fun sortFiles(files: List<RecentFileItem>, sortOrder: SortOrder): List<RecentFileItem> {
+    return when (sortOrder) {
+        SortOrder.RECENT -> files.sortedByDescending { it.timestamp }
+        SortOrder.TITLE_ASC -> files.sortedBy { it.title?.lowercase() ?: it.displayName.lowercase() }
+        SortOrder.AUTHOR_ASC -> files.sortedWith(compareBy(nullsLast()) { it.author?.lowercase() })
+        SortOrder.PERCENT_ASC -> files.sortedBy { it.progressPercentage ?: 0f }
+        SortOrder.PERCENT_DESC -> files.sortedByDescending { it.progressPercentage ?: 0f }
+        SortOrder.SIZE_ASC -> files.sortedBy { it.fileSize }
+        SortOrder.SIZE_DESC -> files.sortedByDescending { it.fileSize }
+    }
+}

app/src/main/java/com/aryan/reader/MainActivity.kt

@@ -45,7 +45,9 @@ import androidx.compose.foundation.isSystemInDarkTheme
 import androidx.compose.runtime.getValue
 import androidx.core.splashscreen.SplashScreen.Companion.installSplashScreen
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import androidx.media3.common.util.UnstableApi
 
+@UnstableApi
 class MainActivity : AppCompatActivity() {
 
     private val viewModel: MainViewModel by viewModels()
@@ -91,12 +93,14 @@ class MainActivity : AppCompatActivity() {
                 AppThemeMode.SYSTEM -> isSystemInDarkTheme()
             }
 
+            val textDimFactor = if (darkTheme) uiState.appTextDimFactorDark else uiState.appTextDimFactorLight
+
             AppTheme(
                 darkTheme = darkTheme,
                 dynamicColor = uiState.appSeedColor == null,
                 seedColor = uiState.appSeedColor,
                 contrastLevel = uiState.appContrastOption.value,
-                textDimFactor = uiState.appTextDimFactor
+                textDimFactor = textDimFactor
             ) {
                 Surface(
                     modifier = Modifier.fillMaxSize(),

app/src/main/java/com/aryan/reader/MainPreferenceKeys.kt

@@ -0,0 +1,14 @@
+package com.aryan.reader
+
+internal const val KEY_RENDER_MODE = "render_mode"
+internal const val KEY_FOLDER_SYNC_ENABLED = "folder_sync_enabled"
+internal const val KEY_MAIN_SCREEN_START_PAGE = "main_screen_start_page"
+internal const val KEY_LIBRARY_SCREEN_START_PAGE = "library_screen_start_page"
+internal const val KEY_LAST_VIEWING_SHELF_ID = "last_viewing_shelf_id"
+internal const val KEY_LAST_ADDING_BOOKS_TO_SHELF = "last_adding_books_to_shelf"
+
+internal const val KEY_FILTER_FILE_TYPES = "filter_file_types"
+internal const val KEY_FILTER_FOLDERS = "filter_folders"
+internal const val KEY_FILTER_READ_STATUS = "filter_read_status"
+internal const val KEY_FILTER_TAG_IDS = "filter_tag_ids"
+internal const val KEY_DEFAULT_TAGS_SEEDED = "default_tags_seeded"

app/src/main/java/com/aryan/reader/MainScreen.kt

@@ -22,10 +22,9 @@ package com.aryan.reader
 
 import androidx.activity.ComponentActivity
 import androidx.activity.enableEdgeToEdge
+import androidx.annotation.OptIn
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.padding
-import androidx.compose.foundation.pager.HorizontalPager
-import androidx.compose.foundation.pager.rememberPagerState
 import androidx.compose.material3.Icon
 import androidx.compose.material3.NavigationBar
 import androidx.compose.material3.NavigationBarItem
@@ -33,17 +32,15 @@ import androidx.compose.material3.Scaffold
 import androidx.compose.material3.Text
 import androidx.compose.material3.windowsizeclass.WindowSizeClass
 import androidx.compose.runtime.Composable
-import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.SideEffect
 import androidx.compose.runtime.getValue
-import androidx.compose.runtime.rememberCoroutineScope
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.res.stringResource
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import androidx.media3.common.util.UnstableApi
 import androidx.navigation.NavHostController
-import kotlinx.coroutines.launch
 
 sealed class BottomBarScreen(val route: String, val stringResId: Int, val iconResId: Int) {
     object Home : BottomBarScreen("home", R.string.nav_home, R.drawable.home)
@@ -55,6 +52,7 @@ private val bottomBarItems = listOf(
     BottomBarScreen.Library,
 )
 
+@OptIn(UnstableApi::class)
 @Composable
 fun MainScreen(
     viewModel: MainViewModel,
@@ -75,21 +73,7 @@ fun MainScreen(
         if (viewingShelfName != null) {
             ShelfScreen(viewModel = viewModel)
         } else {
-            val pagerState = rememberPagerState(
-                initialPage = uiState.mainScreenStartPage,
-                pageCount = { bottomBarItems.size }
-            )
-            val scope = rememberCoroutineScope()
-
-            LaunchedEffect(uiState.mainScreenStartPage) {
-                if (pagerState.currentPage != uiState.mainScreenStartPage) {
-                    pagerState.animateScrollToPage(uiState.mainScreenStartPage)
-                }
-            }
-
-            LaunchedEffect(pagerState.currentPage) {
-                viewModel.setMainScreenPage(pagerState.currentPage)
-            }
+            val selectedPage = uiState.mainScreenStartPage.coerceIn(0, bottomBarItems.lastIndex)
 
             Scaffold(
                 contentWindowInsets = androidx.compose.foundation.layout.WindowInsets(0, 0, 0, 0),
@@ -99,23 +83,28 @@ fun MainScreen(
                             NavigationBarItem(
                                 icon = { Icon(painterResource(id = screen.iconResId), contentDescription = stringResource(screen.stringResId)) },
                                 label = { Text(stringResource(screen.stringResId)) },
-                                selected = pagerState.currentPage == index,
-                                onClick = { scope.launch { pagerState.animateScrollToPage(index) } }
+                                selected = selectedPage == index,
+                                onClick = {
+                                    ReaderPerfLog.d("MainPager click page=$index route=${screen.route}")
+                                    if (selectedPage != index) {
+                                        val animStart = ReaderPerfLog.nowNanos()
+                                        viewModel.setMainScreenPage(index)
+                                        ReaderPerfLog.d(
+                                            "MainPager settled page=$index elapsed=${ReaderPerfLog.elapsedMs(animStart)}ms"
+                                        )
+                                    }
+                                }
                             )
                         }
                     }
                 }
             ) { innerPadding ->
-                HorizontalPager(
-                    state = pagerState,
+                androidx.compose.foundation.layout.Box(
                     modifier = Modifier
                         .fillMaxSize()
-                        .padding(innerPadding),
-                    key = { bottomBarItems[it].route },
-                    beyondViewportPageCount = 1,
-                    userScrollEnabled = false
-                ) { page ->
-                    when (page) {
+                        .padding(innerPadding)
+                ) {
+                    when (selectedPage) {
                         0 -> HomeScreen(
                             viewModel = viewModel,
                             windowSizeClass = windowSizeClass,

app/src/main/java/com/aryan/reader/MainViewModel.kt

@@ -38,7 +38,7 @@ import kotlinx.serialization.protobuf.ProtoBuf
 import com.aryan.reader.paginatedreader.semanticBlockModule
 import android.provider.DocumentsContract
 import android.provider.OpenableColumns
-import androidx.annotation.StringRes
+import androidx.annotation.OptIn
 import androidx.compose.ui.graphics.toArgb
 import androidx.core.content.edit
 import androidx.core.graphics.createBitmap
@@ -48,6 +48,7 @@ import androidx.credentials.exceptions.NoCredentialException
 import androidx.documentfile.provider.DocumentFile
 import androidx.lifecycle.AndroidViewModel
 import androidx.lifecycle.viewModelScope
+import androidx.media3.common.util.UnstableApi
 import androidx.work.ExistingWorkPolicy
 import androidx.work.OneTimeWorkRequestBuilder
 import androidx.work.WorkInfo
@@ -64,8 +65,8 @@ import com.aryan.reader.data.RecentFileItem
 import com.aryan.reader.data.RecentFilesRepository
 import com.aryan.reader.data.RemoteConfigRepository
 import com.aryan.reader.data.ShelfMetadata
-import com.aryan.reader.data.SmartCollectionEngine
 import com.aryan.reader.data.TagEntity
+import com.aryan.reader.data.getUri
 import com.aryan.reader.data.toBookMetadata
 import com.aryan.reader.data.toRecentFileItem
 import com.aryan.reader.epub.CalibreBundleExtractor
@@ -75,6 +76,7 @@ import com.aryan.reader.epub.EpubParser
 import com.aryan.reader.epub.ImportedFileCache
 import com.aryan.reader.epub.MobiParser
 import com.aryan.reader.epub.SingleFileImporter
+import com.aryan.reader.epub.hasReadableExtractedContent
 import com.aryan.reader.ml.ISpeechBubbleDetector
 import com.aryan.reader.ml.SpeechBubble
 import com.aryan.reader.paginatedreader.Locator
@@ -120,60 +122,18 @@ import kotlinx.coroutines.sync.Mutex
 import kotlinx.coroutines.sync.withLock
 import kotlinx.coroutines.withContext
 import kotlinx.coroutines.withTimeoutOrNull
+import kotlinx.serialization.ExperimentalSerializationApi
 import org.json.JSONArray
 import org.json.JSONObject
 import timber.log.Timber
 import java.io.File
 import java.io.FileOutputStream
-import java.util.Date
 import java.util.UUID
 import java.util.concurrent.ConcurrentHashMap
 import java.util.concurrent.CancellationException
 import java.util.concurrent.Executors.newSingleThreadExecutor
 import java.util.concurrent.TimeUnit
 
-private const val KEY_RENDER_MODE = "render_mode"
-private const val KEY_FOLDER_SYNC_ENABLED = "folder_sync_enabled"
-private const val KEY_MAIN_SCREEN_START_PAGE = "main_screen_start_page"
-private const val KEY_LIBRARY_SCREEN_START_PAGE = "library_screen_start_page"
-private const val KEY_LAST_VIEWING_SHELF_ID = "last_viewing_shelf_id"
-private const val KEY_LAST_ADDING_BOOKS_TO_SHELF = "last_adding_books_to_shelf"
-
-private const val KEY_FILTER_FILE_TYPES = "filter_file_types"
-private const val KEY_FILTER_FOLDERS = "filter_folders"
-private const val KEY_FILTER_READ_STATUS = "filter_read_status"
-private const val KEY_FILTER_TAG_IDS = "filter_tag_ids"
-private const val KEY_DEFAULT_TAGS_SEEDED = "default_tags_seeded"
-private val PDF_VIEWER_FILE_TYPES = setOf(FileType.PDF, FileType.CBZ, FileType.CBR, FileType.CB7)
-private val EPUB_READER_FILE_TYPES = setOf(
-    FileType.EPUB,
-    FileType.MOBI,
-    FileType.MD,
-    FileType.TXT,
-    FileType.HTML,
-    FileType.FB2,
-    FileType.DOCX,
-    FileType.ODT,
-    FileType.FODT
-)
-
-data class BannerMessage(val message: String, val isError: Boolean = false, val isPersistent: Boolean = false)
-
-data class ImportResult(
-    val internalUri: Uri,
-    val bookId: String,
-    val type: FileType,
-    val bundleResult: CalibreBundleResult? = null
-)
-
-data class UserData(
-    val uid: String, val displayName: String?, val photoUrl: String?, val email: String?
-)
-
-data class NavigationEvent(
-    val route: String, val bookId: String? = null, val uri: Uri? = null
-)
-
 private data class SpeechBubbleCacheKey(
     val documentId: String,
     val pageIndex: Int
@@ -187,166 +147,8 @@ private data class CachedSpeechBubble(
     val maskBitmap: Bitmap?
 )
 
-enum class AddBooksSource(@StringRes val labelRes: Int) {
-    UNSHELVED(R.string.add_books_source_unshelved),
-    ALL_BOOKS(R.string.add_books_source_all_books)
-}
-
-enum class AppThemeMode(@StringRes val labelRes: Int) {
-    SYSTEM(R.string.app_theme_mode_system),
-    LIGHT(R.string.app_theme_mode_light),
-    DARK(R.string.app_theme_mode_dark)
-}
-
-enum class AppContrastOption(@StringRes val labelRes: Int, val value: Double) {
-    STANDARD(R.string.app_contrast_standard, 0.0),
-    MEDIUM(R.string.app_contrast_medium, 0.5),
-    HIGH(R.string.app_contrast_high, 1.0)
-}
-
-data class CustomAppTheme(
-    val id: String,
-    val name: String,
-    val seedColor: androidx.compose.ui.graphics.Color
-)
-
-enum class FileType {
-    PDF, EPUB, MOBI, MD, TXT, HTML, FB2, CBZ, CBR, CB7, DOCX, ODT, FODT
-}
-
-enum class RenderMode {
-    VERTICAL_SCROLL, PAGINATED
-}
-
-data class DeviceItem(val deviceId: String, val deviceName: String, val lastSeen: Date?)
-
-data class DeviceLimitReachedState(
-    val isLimitReached: Boolean = false, val registeredDevices: List<DeviceItem> = emptyList()
-)
-
-data class SyncedFolder(
-    val uriString: String, val name: String, val lastScanTime: Long, val allowedFileTypes: Set<FileType> = FileType.entries.toSet()
-)
-
-enum class ShelfType { MANUAL, SMART, TAG, SERIES, FOLDER }
-
-data class Shelf(
-    val id: String,
-    val name: String,
-    val type: ShelfType,
-    val books: List<RecentFileItem>,
-    val directBooks: List<RecentFileItem> = books,
-    val parentShelfId: String? = null,
-    val childShelfIds: List<String> = emptyList(),
-    val depth: Int = 0,
-    val sortKey: String = name.lowercase()
-) {
-    val bookCount: Int get() = books.size
-    val topBook: RecentFileItem? get() = books.maxByOrNull { it.timestamp }
-    val directBookCount: Int get() = directBooks.size
-    val childShelfCount: Int get() = childShelfIds.size
-}
-
-enum class SortOrder(@StringRes val labelRes: Int) {
-    RECENT(R.string.sort_recent),
-    TITLE_ASC(R.string.sort_title_az),
-    AUTHOR_ASC(R.string.sort_author_az),
-    PERCENT_ASC(R.string.sort_percent_asc),
-    PERCENT_DESC(R.string.sort_percent_desc),
-    SIZE_ASC(R.string.sort_size_smallest),
-    SIZE_DESC(R.string.sort_size_biggest)
-}
-
-enum class ReadStatusFilter(@StringRes val labelRes: Int) {
-    ALL(R.string.read_status_all),
-    UNREAD(R.string.read_status_unread),
-    IN_PROGRESS(R.string.read_status_in_progress),
-    COMPLETED(R.string.read_status_completed)
-}
-
-data class LibraryFilters(
-    val fileTypes: Set<FileType> = emptySet(),
-    val sourceFolders: Set<String> = emptySet(),
-    val readStatus: ReadStatusFilter = ReadStatusFilter.ALL,
-    val tagIds: Set<String> = emptySet()
-) {
-    val isActive: Boolean
-        get() = fileTypes.isNotEmpty() ||
-            sourceFolders.isNotEmpty() ||
-            readStatus != ReadStatusFilter.ALL ||
-            tagIds.isNotEmpty()
-}
-
-data class ReaderScreenState(
-    val selectedPdfUri: Uri? = null,
-    val selectedBookId: String? = null,
-    val selectedEpubBook: EpubBook? = null,
-    val selectedEpubUri: Uri? = null,
-    val selectedFileType: FileType? = null,
-    val isLoading: Boolean = false,
-    val errorMessage: String? = null,
-    val contextualActionItems: Set<RecentFileItem> = emptySet(),
-    val renderMode: RenderMode = RenderMode.VERTICAL_SCROLL,
-    val sortOrder: SortOrder = SortOrder.RECENT,
-    val initialLocator: Locator? = null,
-    val initialCfi: String? = null,
-    val initialBookmarksJson: String? = null,
-    val initialHighlightsJson: String? = null,
-    val initialPageInBook: Int? = null,
-    val shelves: List<Shelf> = emptyList(),
-    val viewingShelfId: String? = null,
-    val isAddingBooksToShelf: Boolean = false,
-    val showCreateShelfDialog: Boolean = false,
-    val mainScreenStartPage: Int = 0,
-    val libraryScreenStartPage: Int = 0,
-    val showRenameShelfDialogFor: String? = null,
-    val showDeleteShelfDialogFor: String? = null,
-    val addBooksSource: AddBooksSource = AddBooksSource.UNSHELVED,
-    val booksSelectedForAdding: Set<String> = emptySet(),
-    val booksAvailableForAdding: List<RecentFileItem> = emptyList(),
-    val contextualActionShelfIds: Set<String> = emptySet(),
-    val currentUser: UserData? = null,
-    val isAuthMenuExpanded: Boolean = false,
-    val isProUser: Boolean = false,
-    val credits: Int = 0,
-    val isSyncEnabled: Boolean = false,
-    val isFolderSyncEnabled: Boolean = false,
-    val bannerMessage: BannerMessage? = null,
-    val deviceLimitState: DeviceLimitReachedState = DeviceLimitReachedState(),
-    val isReplacingDevice: Boolean = false,
-    val isRequestingDrivePermission: Boolean = false,
-    val downloadingBookIds: Set<String> = emptySet(),
-    val uploadingBookIds: Set<String> = emptySet(),
-    val syncedFolders: List<SyncedFolder> = emptyList(),
-    val lastFolderScanTime: Long? = null,
-    val hasUnreadFeedback: Boolean = false,
-    val searchQuery: String = "",
-    val isSearchActive: Boolean = false,
-    val isRefreshing: Boolean = false,
-    val reflowProgress: Float? = null,
-    val recentFiles: List<RecentFileItem> = emptyList(),
-    val allRecentFiles: List<RecentFileItem> = emptyList(),
-    val rawLibraryFiles: List<RecentFileItem> = emptyList(),
-    val pinnedHomeBookIds: Set<String> = emptySet(),
-    val pinnedLibraryBookIds: Set<String> = emptySet(),
-    val libraryFilters: LibraryFilters = LibraryFilters(),
-    val recentFilesLimit: Int = 0,
-    val isTabsEnabled: Boolean = false,
-    val openTabIds: List<String> = emptyList(),
-    val openTabs: List<RecentFileItem> = emptyList(),
-    val activeTabBookId: String? = null,
-    val showExternalFileSavePromptFor: String? = null,
-    val externalFileBehavior: String = "ASK",
-    val useStrictFileFilter: Boolean = false,
-    val appThemeMode: AppThemeMode = AppThemeMode.SYSTEM,
-    val appContrastOption: AppContrastOption = AppContrastOption.STANDARD,
-    val appTextDimFactor: Float = 1.0f,
-    val appSeedColor: androidx.compose.ui.graphics.Color? = null,
-    val customAppThemes: List<CustomAppTheme> = emptyList(),
-    val allTags: List<TagEntity> = emptyList(),
-    val showTagSelectionDialogFor: Set<String> = emptySet(),
-)
-
+@kotlin.OptIn(ExperimentalSerializationApi::class)
+@UnstableApi
 open class MainViewModel(application: Application) : AndroidViewModel(application) {
     private val appContext: Context = application.applicationContext
     private val authRepository = AuthRepository(appContext)
@@ -380,6 +182,7 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
     private val _prefsUpdateFlow = MutableStateFlow(0L)
     private val prefsListener: SharedPreferences.OnSharedPreferenceChangeListener
     private val feedbackRepository = FeedbackRepository(appContext)
+    private val libraryStateProjector = LibraryStateProjector(AndroidFolderPathResolver())
     private var feedbackListener: Any? = null
     private val importMutex = Mutex()
     private val epubRecoveryMutex = Mutex()
@@ -611,7 +414,7 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
                     val totalFileLength = if (contentLength != -1L) downloadedBytes + contentLength else -1L
 
                     val input = connection.inputStream
-                    val output = java.io.FileOutputStream(tempFile, isPartial)
+                    val output = FileOutputStream(tempFile, isPartial)
                     val data = ByteArray(16 * 1024)
                     var count: Int
 
@@ -744,7 +547,8 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
             appContrastOption = try {
                 AppContrastOption.valueOf(prefs.getString(KEY_APP_CONTRAST_OPTION, AppContrastOption.STANDARD.name) ?: AppContrastOption.STANDARD.name)
             } catch (_: Exception) { AppContrastOption.STANDARD },
-            appTextDimFactor = prefs.getFloat(KEY_APP_TEXT_DIM_FACTOR, 1.0f),
+            appTextDimFactorLight = prefs.getFloat(KEY_APP_TEXT_DIM_FACTOR_LIGHT, prefs.getFloat(KEY_APP_TEXT_DIM_FACTOR, 1.0f)),
+            appTextDimFactorDark = prefs.getFloat(KEY_APP_TEXT_DIM_FACTOR_DARK, prefs.getFloat(KEY_APP_TEXT_DIM_FACTOR, 1.0f)),
             appSeedColor = if (prefs.contains(KEY_APP_SEED_COLOR)) androidx.compose.ui.graphics.Color(prefs.getInt(KEY_APP_SEED_COLOR, 0)) else null,
             customAppThemes = loadCustomAppThemes(prefs)
         )
@@ -808,299 +612,24 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
     open val uiState: StateFlow<ReaderScreenState> = combine(
         _internalState, libraryFlow, tagFlow
     ) { internalState, (recentFilesFromDb, dbShelves, shelfRefs), (dbTags, tagRefs) ->
-        val tagsById = dbTags.associateBy { it.id }
-        val bookTagsMap = tagRefs.groupBy { it.bookId }.mapValues { entry ->
-            entry.value.mapNotNull { tagsById[it.tagId] }
+        withContext(Dispatchers.Default) {
+            libraryStateProjector.project(
+                LibraryProjectionInput(
+                    state = internalState,
+                    recentFilesFromDb = recentFilesFromDb,
+                    dbShelves = dbShelves,
+                    shelfRefs = shelfRefs,
+                    dbTags = dbTags,
+                    tagRefs = tagRefs
+                )
+            )
         }
-
-        val allLibraryFiles = recentFilesFromDb
-            .filterNot { it.bookId.endsWith("_reflow") }
-            .map { item ->
-            item.copy(tags = bookTagsMap[item.bookId] ?: emptyList())
-        }
-
-        val query = internalState.searchQuery.trim()
-        val rawFilteredByQuery = if (query.isBlank()) {
-            allLibraryFiles
-        } else {
-            allLibraryFiles.filter { item ->
-                item.displayName.contains(query, ignoreCase = true) ||
-                    item.title?.contains(query, ignoreCase = true) == true ||
-                    item.author?.contains(query, ignoreCase = true) == true ||
-                    item.tags.any { tag -> tag.name.contains(query, ignoreCase = true) }
-            }
-        }
-
-        val filters = internalState.libraryFilters
-        val libraryFiltered = rawFilteredByQuery.filter { item ->
-            val matchType = if (filters.fileTypes.isNotEmpty()) item.type in filters.fileTypes else true
-            val matchFolder = if (filters.sourceFolders.isNotEmpty()) {
-                val matchesInApp = filters.sourceFolders.contains("IN_APP_STORAGE") && item.sourceFolderUri == null && item.uriString?.startsWith("opds-pse") != true
-                val matchesSynced = item.sourceFolderUri in filters.sourceFolders
-                matchesInApp || matchesSynced
-            } else true
-            val progress = item.progressPercentage ?: 0f
-            val matchStatus = when (filters.readStatus) {
-                ReadStatusFilter.ALL -> true
-                ReadStatusFilter.UNREAD -> progress == 0f
-                ReadStatusFilter.IN_PROGRESS -> progress > 0f && progress < 100f
-                ReadStatusFilter.COMPLETED -> progress >= 100f
-            }
-            val matchTags = if (filters.tagIds.isNotEmpty()) {
-                item.tags.any { it.id in filters.tagIds }
-            } else true
-            matchType && matchFolder && matchStatus && matchTags
-        }
-
-        fun sortFiles(files: List<RecentFileItem>): List<RecentFileItem> {
-            return when (internalState.sortOrder) {
-                SortOrder.RECENT -> files.sortedByDescending { it.timestamp }
-                SortOrder.TITLE_ASC -> files.sortedBy { it.title?.lowercase() ?: it.displayName.lowercase() }
-                SortOrder.AUTHOR_ASC -> files.sortedWith(compareBy(nullsLast()) { it.author?.lowercase() })
-                SortOrder.PERCENT_ASC -> files.sortedBy { it.progressPercentage ?: 0f }
-                SortOrder.PERCENT_DESC -> files.sortedByDescending { it.progressPercentage ?: 0f }
-                SortOrder.SIZE_ASC -> files.sortedBy { it.fileSize }
-                SortOrder.SIZE_DESC -> files.sortedByDescending { it.fileSize }
-            }
-        }
-
-        val sortedLibraryFiles = sortFiles(libraryFiltered)
-        val visibleRecentFiles = sortFiles(allLibraryFiles.filter { it.isRecent }).take(
-            if (internalState.recentFilesLimit > 0) internalState.recentFilesLimit else Int.MAX_VALUE
-        )
-        val openTabsList = internalState.openTabIds.mapNotNull { tabId -> allLibraryFiles.find { it.bookId == tabId } }
-        val allShelves = mutableListOf<Shelf>()
-        val shelvedBookIds = mutableSetOf<String>()
-        val baseFilesMap = allLibraryFiles.associateBy { it.bookId }
-
-        dbShelves.forEach { shelfEntity ->
-            if (shelfEntity.isSmart && shelfEntity.smartRulesJson != null) {
-                val rules = SmartCollectionEngine.fromJson(shelfEntity.smartRulesJson)
-                if (rules != null) {
-                    val matchingBooks = allLibraryFiles.filter { SmartCollectionEngine.evaluate(it, rules) }
-                    allShelves.add(Shelf(shelfEntity.id, shelfEntity.name, ShelfType.SMART, sortFiles(matchingBooks)))
-                    shelvedBookIds.addAll(matchingBooks.map { it.bookId })
-                }
-            } else {
-                val bookIdsInShelf = shelfRefs.filter { it.shelfId == shelfEntity.id }.sortedBy { it.addedAt }.map { it.bookId }
-                val booksInShelf = bookIdsInShelf.mapNotNull { baseFilesMap[it] }
-                allShelves.add(Shelf(shelfEntity.id, shelfEntity.name, ShelfType.MANUAL, sortFiles(booksInShelf)))
-                shelvedBookIds.addAll(bookIdsInShelf)
-            }
-        }
-
-        val tagShelves = dbTags.mapNotNull { tag ->
-            val taggedBooks = allLibraryFiles.filter { item -> item.tags.any { it.id == tag.id } }
-            if (taggedBooks.isEmpty()) {
-                null
-            } else {
-                Shelf("tag_${tag.id}", tag.name, ShelfType.TAG, sortFiles(taggedBooks))
-            }
-        }
-        allShelves.addAll(tagShelves)
-
-        val seriesShelves = allLibraryFiles
-            .filter { !it.seriesName.isNullOrBlank() }
-            .groupBy { it.seriesName!! }
-            .filter { it.value.size >= 2 }
-            .map { (series, books) ->
-                val sortedSeries = books.sortedBy { it.seriesIndex ?: 999.0 }
-                shelvedBookIds.addAll(books.map { it.bookId })
-                Shelf("series_$series", series, ShelfType.SERIES, sortedSeries)
-            }
-        allShelves.addAll(seriesShelves)
-
-        val folderShelves = buildFolderShelves(
-            allLibraryFiles = allLibraryFiles,
-            syncedFolders = internalState.syncedFolders,
-            sortFiles = ::sortFiles
-        ).also { shelves ->
-            shelves.forEach { shelf ->
-                shelvedBookIds.addAll(shelf.books.map { it.bookId })
-            }
-        }
-        allShelves.addAll(folderShelves)
-
-        val unshelvedBooks = allLibraryFiles.filter { it.bookId !in shelvedBookIds }
-        allShelves.add(Shelf("unshelved", "Unshelved", ShelfType.MANUAL, sortFiles(unshelvedBooks)))
-
-        allShelves.sortWith(compareBy({ it.type.ordinal }, { it.sortKey }))
-
-        val validShelfIds = allShelves.mapTo(mutableSetOf()) { it.id }
-        val viewingShelfId = internalState.viewingShelfId?.takeIf { it in validShelfIds }
-        val selectedShelfIds = internalState.contextualActionShelfIds.filterTo(mutableSetOf()) { it in validShelfIds }
-
-        val booksAvailableForAdding = if (internalState.isAddingBooksToShelf && viewingShelfId != null) {
-            val currentShelfBookIds = allShelves
-                .find { it.id == viewingShelfId }
-                ?.books
-                ?.map { it.bookId }
-                ?.toSet()
-                ?: emptySet()
-            when (internalState.addBooksSource) {
-                AddBooksSource.UNSHELVED -> unshelvedBooks
-                AddBooksSource.ALL_BOOKS -> allLibraryFiles.filter { it.bookId !in currentShelfBookIds }
-            }
-        } else emptyList()
-
-        internalState.copy(
-            recentFiles = visibleRecentFiles,
-            allRecentFiles = sortedLibraryFiles,
-            rawLibraryFiles = allLibraryFiles,
-            viewingShelfId = viewingShelfId,
-            isAddingBooksToShelf = internalState.isAddingBooksToShelf && viewingShelfId != null,
-            contextualActionShelfIds = selectedShelfIds,
-            contextualActionItems = internalState.contextualActionItems.mapNotNull { ctx -> allLibraryFiles.find { it.bookId == ctx.bookId } }.toSet(),
-            shelves = allShelves,
-            openTabs = openTabsList,
-            booksAvailableForAdding = booksAvailableForAdding,
-            allTags = dbTags
-        )
     }.stateIn(
         scope = viewModelScope,
         started = SharingStarted.WhileSubscribed(5000),
         initialValue = _internalState.value
     )
 
-    private data class FolderShelfAccumulator(
-        val id: String,
-        val name: String,
-        val depth: Int,
-        val parentShelfId: String?,
-        val sortPath: String,
-        val books: MutableList<RecentFileItem> = mutableListOf(),
-        val directBooks: MutableList<RecentFileItem> = mutableListOf(),
-        val childShelfIds: MutableList<String> = mutableListOf()
-    )
-
-    private fun buildFolderShelves(
-        allLibraryFiles: List<RecentFileItem>,
-        syncedFolders: List<SyncedFolder>,
-        sortFiles: (List<RecentFileItem>) -> List<RecentFileItem>
-    ): List<Shelf> {
-        val folderNamesByUri = syncedFolders.associate { it.uriString to it.name }
-
-        return allLibraryFiles
-            .filter { it.sourceFolderUri != null }
-            .groupBy { it.sourceFolderUri!! }
-            .flatMap { (folderUri, books) ->
-                val rootName = folderNamesByUri[folderUri] ?: "Local Folder"
-                val rootShelfId = "folder_$folderUri"
-                val rootAccumulator = FolderShelfAccumulator(
-                    id = rootShelfId,
-                    name = rootName,
-                    depth = 0,
-                    parentShelfId = null,
-                    sortPath = ""
-                )
-                val rootShelf = Shelf(
-                    id = rootShelfId,
-                    name = rootName,
-                    type = ShelfType.FOLDER,
-                    books = sortFiles(books),
-                    directBooks = mutableListOf<RecentFileItem>().also { direct ->
-                        direct.addAll(books.filter { getRelativeFolderSegments(it).isEmpty() })
-                    },
-                    childShelfIds = emptyList(),
-                    depth = 0,
-                    sortKey = "folder:${rootName.lowercase()}:"
-                )
-
-                val nestedShelves = linkedMapOf<String, FolderShelfAccumulator>()
-                books.forEach { book ->
-                    rootAccumulator.books.add(book)
-                    val segments = getRelativeFolderSegments(book)
-                    if (segments.isEmpty()) {
-                        rootAccumulator.directBooks.add(book)
-                    }
-                    var currentPath = ""
-                    var parentShelfId = rootShelfId
-                    segments.forEachIndexed { index, segment ->
-                        currentPath = if (currentPath.isEmpty()) segment else "$currentPath/$segment"
-                        val shelfId = "folder_$folderUri::$currentPath"
-                        val accumulator = nestedShelves.getOrPut(currentPath) {
-                            val newShelf = FolderShelfAccumulator(
-                                id = shelfId,
-                                name = segment,
-                                depth = index + 1,
-                                parentShelfId = parentShelfId,
-                                sortPath = currentPath.lowercase()
-                            )
-                            if (parentShelfId == rootShelfId) {
-                                rootAccumulator.childShelfIds.add(shelfId)
-                            } else {
-                                nestedShelves.values.find { it.id == parentShelfId }?.childShelfIds?.add(shelfId)
-                            }
-                            newShelf
-                        }
-                        accumulator.books.add(book)
-                        if (index == segments.lastIndex) {
-                            accumulator.directBooks.add(book)
-                        }
-                        parentShelfId = shelfId
-                    }
-                }
-
-                val sortedNestedShelves = nestedShelves
-                    .values
-                    .sortedBy { it.sortPath }
-                    .map { shelf ->
-                        Shelf(
-                            id = shelf.id,
-                            name = shelf.name,
-                            type = ShelfType.FOLDER,
-                            books = sortFiles(shelf.books),
-                            directBooks = sortFiles(shelf.directBooks),
-                            parentShelfId = shelf.parentShelfId,
-                            childShelfIds = shelf.childShelfIds.sortedBy { it.substringAfterLast("::").lowercase() },
-                            depth = shelf.depth,
-                            sortKey = "folder:${rootName.lowercase()}:${shelf.sortPath}"
-                        )
-                    }
-
-                listOf(
-                    rootShelf.copy(
-                        directBooks = sortFiles(rootAccumulator.directBooks),
-                        childShelfIds = rootAccumulator.childShelfIds.sortedBy { it.substringAfterLast("::").lowercase() }
-                    )
-                ) + sortedNestedShelves
-            }
-    }
-
-    private fun getRelativeFolderSegments(item: RecentFileItem): List<String> {
-        val documentUriString = item.uriString ?: return emptyList()
-        val rootFolderUriString = item.sourceFolderUri ?: return emptyList()
-
-        return try {
-            val documentUri = documentUriString.toUri()
-            val rootFolderUri = rootFolderUriString.toUri()
-            val rootDocId = DocumentsContract.getTreeDocumentId(rootFolderUri)
-            val documentId = when {
-                DocumentsContract.isDocumentUri(appContext, documentUri) -> DocumentsContract.getDocumentId(documentUri)
-                DocumentsContract.isTreeUri(documentUri) -> DocumentsContract.getTreeDocumentId(documentUri)
-                else -> return emptyList()
-            }
-
-            val rootPath = rootDocId.substringAfter(':', "")
-            val documentPath = documentId.substringAfter(':', "")
-            val relativeDocumentPath = when {
-                rootPath.isBlank() -> documentPath
-                documentPath == rootPath -> ""
-                documentPath.startsWith("$rootPath/") -> documentPath.removePrefix("$rootPath/")
-                else -> documentPath
-            }
-
-            relativeDocumentPath
-                .substringBeforeLast('/', "")
-                .split('/')
-                .map { Uri.decode(it).trim() }
-                .filter { it.isNotEmpty() }
-        } catch (e: Exception) {
-            Timber.tag("FolderShelves").w(e, "Failed to derive relative folder path for ${item.displayName}")
-            emptyList()
-        }
-    }
-
     fun setTabsEnabled(enabled: Boolean) {
         prefs.edit { putBoolean(KEY_TABS_ENABLED, enabled) }
         _internalState.update { it.copy(isTabsEnabled = enabled) }
@@ -1529,7 +1058,6 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
         Timber.d("ViewModel instance created.")
         WorkManager.getInstance(application).cancelUniqueWork(FolderSyncWorker.WORK_NAME)
 
-        // --- ADD THIS BLOCK ---
         val locatorConverter = LocatorConverter(
             bookCacheDao,
             ProtoBuf { serializersModule = semanticBlockModule },
@@ -1814,7 +1342,13 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
                     inputStream = inputStream,
                     bookId = bookId,
                     originalBookNameHint = displayName
-                ) ?: throw Exception("MobiParser returned null. The file might be DRM-protected or invalid.")
+                ) ?: throw Exception(
+                    if (MobiParser.isNativeParserAvailable) {
+                        "MobiParser returned null. The file might be DRM-protected or invalid."
+                    } else {
+                        MobiParser.nativeParserUnavailableMessage()
+                    }
+                )
 
                 FileType.FB2 -> fb2Parser.createFb2Book(
                     inputStream = inputStream,
@@ -1860,10 +1394,7 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
                 if (latestState.selectedBookId != bookId || latestState.selectedEpubUri != uri) {
                     return@withLock
                 }
-                if (latestState.selectedEpubBook?.extractionBasePath?.let { path ->
-                        path.isNotBlank() && File(path).exists()
-                    } == true
-                ) {
+                if (latestState.selectedEpubBook?.hasReadableExtractedContent() == true) {
                     return@withLock
                 }
 
@@ -2822,7 +2353,11 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
                     )
                 }
 
-                scanSyncedFolder()
+                triggerFolderSyncWorker(
+                    metadataOnly = false,
+                    showFeedback = true,
+                    targetFolderUriString = newFolder.uriString
+                )
 
                 showBanner(appContext.getString(R.string.banner_folder_added, name))
 
@@ -2835,6 +2370,11 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
 
     fun removeSyncedFolder(folder: SyncedFolder) {
         viewModelScope.launch {
+            val workManager = WorkManager.getInstance(appContext)
+            ReaderPerfLog.d("FolderRemove request folder=${folder.uriString}")
+            workManager.cancelUniqueWork(FolderSyncWorker.WORK_NAME_ONETIME)
+            workManager.cancelUniqueWork(MetadataExtractionWorker.WORK_NAME)
+
             val currentFolders = _internalState.value.syncedFolders.toMutableList()
             currentFolders.removeAll { it.uriString == folder.uriString }
 
@@ -2842,9 +2382,8 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
             _internalState.update { it.copy(syncedFolders = currentFolders) }
 
             val filesToRemove = recentFilesRepository.getFilesBySourceFolder(folder.uriString)
-            filesToRemove.forEach { cleanupBookDataLocally(it.bookId) }
-
             recentFilesRepository.deleteFilesBySourceFolder(folder.uriString)
+            filesToRemove.forEach { cleanupBookDataLocally(it.bookId) }
             try {
                 appContext.contentResolver.releasePersistableUriPermission(
                     folder.uriString.toUri(),
@@ -2855,7 +2394,7 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
             }
 
             if (currentFolders.isEmpty()) {
-                WorkManager.getInstance(appContext).cancelUniqueWork(FolderSyncWorker.WORK_NAME)
+                workManager.cancelUniqueWork(FolderSyncWorker.WORK_NAME)
             }
 
             showBanner(appContext.getString(R.string.banner_folder_removed))
@@ -2870,16 +2409,33 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
         triggerFolderSyncWorker(metadataOnly = false, showFeedback = true)
     }
 
-    private fun triggerFolderSyncWorker(metadataOnly: Boolean, showFeedback: Boolean) {
+    private fun triggerFolderSyncWorker(
+        metadataOnly: Boolean,
+        showFeedback: Boolean,
+        targetFolderUriString: String? = null
+    ) {
         val folders = _internalState.value.syncedFolders
         if (folders.isEmpty()) return
 
-        Timber.tag("FolderSync")
-            .d("Requesting folder sync for ${folders.size} folders (metadataOnly=$metadataOnly, feedback=$showFeedback)")
+        val targetFolderName = targetFolderUriString
+            ?.let { target -> folders.firstOrNull { it.uriString == target }?.name ?: target }
+        ReaderPerfLog.d(
+            "FolderSync request folders=${folders.size} target=${targetFolderName ?: "ALL"} " +
+                "metadataOnly=$metadataOnly feedback=$showFeedback"
+        )
 
         val workManager = WorkManager.getInstance(appContext)
+        if (!metadataOnly) {
+            workManager.cancelUniqueWork(MetadataExtractionWorker.WORK_NAME)
+        }
         val data = androidx.work.Data.Builder()
-            .putBoolean(FolderSyncWorker.KEY_METADATA_ONLY, metadataOnly).build()
+            .putBoolean(FolderSyncWorker.KEY_METADATA_ONLY, metadataOnly)
+            .apply {
+                if (!targetFolderUriString.isNullOrBlank()) {
+                    putString(FolderSyncWorker.KEY_TARGET_FOLDER_URI, targetFolderUriString)
+                }
+            }
+            .build()
 
         val request = OneTimeWorkRequestBuilder<FolderSyncWorker>().setInputData(data).build()
 
@@ -2958,7 +2514,11 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
                 }
 
                 withContext(Dispatchers.Main) {
-                    scanSyncedFolder()
+                    triggerFolderSyncWorker(
+                        metadataOnly = false,
+                        showFeedback = true,
+                        targetFolderUriString = folder.uriString
+                    )
                 }
             }
         }
@@ -2966,12 +2526,17 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
 
     fun disconnectAllSyncedFolders() {
         viewModelScope.launch {
+            val workManager = WorkManager.getInstance(appContext)
+            ReaderPerfLog.d("FolderRemove disconnect all folders=${_internalState.value.syncedFolders.size}")
+            workManager.cancelUniqueWork(FolderSyncWorker.WORK_NAME_ONETIME)
+            workManager.cancelUniqueWork(FolderSyncWorker.WORK_NAME)
+            workManager.cancelUniqueWork(MetadataExtractionWorker.WORK_NAME)
+
             val folders = _internalState.value.syncedFolders
             folders.forEach { folder ->
                 val filesToRemove = recentFilesRepository.getFilesBySourceFolder(folder.uriString)
-                filesToRemove.forEach { cleanupBookDataLocally(it.bookId) }
-
                 recentFilesRepository.deleteFilesBySourceFolder(folder.uriString)
+                filesToRemove.forEach { cleanupBookDataLocally(it.bookId) }
                 try {
                     appContext.contentResolver.releasePersistableUriPermission(
                         folder.uriString.toUri(), Intent.FLAG_GRANT_READ_URI_PERMISSION
@@ -2985,8 +2550,6 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
                 remove(KEY_SYNCED_FOLDER_URI)
             }
             _internalState.update { it.copy(syncedFolders = emptyList()) }
-
-            WorkManager.getInstance(appContext).cancelUniqueWork(FolderSyncWorker.WORK_NAME)
         }
     }
 
@@ -3869,6 +3432,9 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
                 val oneHourAgo = System.currentTimeMillis() - TimeUnit.HOURS.toMillis(1)
                 val allDbIds = recentFilesRepository.getAllFilesForSync().map { it.bookId }.toSet()
                 val validStreamHashes = allDbIds.map { it.hashCode().toString() }.toSet()
+                val validActiveBookCacheDirs = allDbIds.mapTo(mutableSetOf()) {
+                    ImportedFileCache.activeBookDirName(it)
+                }
                 ImportedFileCache.deleteStaleTemporaryBookDirs(appContext, TimeUnit.HOURS.toMillis(1))
 
                 cacheDir.listFiles()?.forEach { file ->
@@ -3879,10 +3445,10 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
                             if (deleted) Timber.d("Sweeper cleaned old temp file: $name")
                         }
                     } else if (ImportedFileCache.isActiveBookDir(name)) {
-                        val bookId = name.removePrefix("imported_file_")
-                        if (bookId !in allDbIds) {
+                        val legacyBookId = name.removePrefix("imported_file_")
+                        if (name !in validActiveBookCacheDirs && legacyBookId !in allDbIds && file.lastModified() < oneHourAgo) {
                             val deleted = file.deleteRecursively()
-                            if (deleted) Timber.d("Sweeper cleaned orphaned extracted cache for: $bookId")
+                            if (deleted) Timber.d("Sweeper cleaned orphaned extracted cache: $name")
                         }
                     } else if (name.startsWith("opds_stream_")) {
                         val bookIdHash = name.removePrefix("opds_stream_")
@@ -4274,6 +3840,7 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
         uri: Uri, bookId: String, type: FileType, originalDisplayName: String? = null, suppressNavigation: Boolean = false, bundleResult: CalibreBundleResult? = null
     ) {
         val openBookStartTime = System.currentTimeMillis()
+        ReaderPerfLog.d("FileOpen start bookId=$bookId type=$type")
         Timber.tag("FileOpenPerf")
             .d("[$bookId] openBook START | type=$type | displayName=$originalDisplayName")
 
@@ -4341,12 +3908,6 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
                 viewModelScope.launch {
                     val recentItem = recentFilesRepository.getFileByBookId(bookId)
 
-                    if (recentItem?.sourceFolderUri != null) {
-                        launch(Dispatchers.IO) {
-                            recentFilesRepository.syncLocalMetadataToFolder(bookId)
-                        }
-                    }
-
                     Timber.tag("FileOpenPerf")
                         .d("[$bookId] Branch: PDF | elapsed=${System.currentTimeMillis() - openBookStartTime}ms")
                     _internalState.update {
@@ -4357,6 +3918,7 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
                             isLoading = false
                         )
                     }
+                    ReaderPerfLog.d("FileOpen ready bookId=$bookId type=$type elapsed=${System.currentTimeMillis() - openBookStartTime}ms")
                     persistReaderSession(bookId, type)
                     addFileToRecent(
                         uri,
@@ -4378,11 +3940,6 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
             } else if (type == FileType.EPUB || type == FileType.MOBI || type == FileType.FB2 || type == FileType.MD || type == FileType.TXT || type == FileType.HTML || type == FileType.DOCX || type == FileType.ODT || type == FileType.FODT) {
                 viewModelScope.launch {
                     val recentItem = recentFilesRepository.getFileByBookId(bookId)
-                    if (recentItem?.sourceFolderUri != null) {
-                        launch(Dispatchers.IO) {
-                            recentFilesRepository.syncLocalMetadataToFolder(bookId)
-                        }
-                    }
                     Timber.tag("FileOpenPerf")
                         .d("[$bookId] Branch: ${type.name} | elapsed=${System.currentTimeMillis() - openBookStartTime}ms")
                     val locator =
@@ -4405,6 +3962,7 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
                             initialHighlightsJson = recentItem?.highlightsJson,
                         )
                     }
+                    ReaderPerfLog.d("FileOpen ready bookId=$bookId type=$type elapsed=${System.currentTimeMillis() - openBookStartTime}ms")
                     persistReaderSession(bookId, type)
 
                     if (!suppressNavigation) {
@@ -4617,87 +4175,11 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
             "text/x-c", "text/x-c++", "text/x-csharp", "text/x-ruby", "text/x-go", "text/x-log" -> FileType.HTML
 
             "text/plain" -> {
-                if (fileName?.endsWith(".md", ignoreCase = true) == true || fileName?.endsWith(".markdown", ignoreCase = true) == true) {
-                    FileType.MD
-                } else if (fileName?.let {
-                        it.endsWith(".csv", ignoreCase = true) || it.endsWith(".tsv", ignoreCase = true) ||
-                                it.endsWith(".json", ignoreCase = true) || it.endsWith(".xml", ignoreCase = true) ||
-                                it.endsWith(".log", ignoreCase = true) || it.endsWith(".java", ignoreCase = true) ||
-                                it.endsWith(".kt", ignoreCase = true) || it.endsWith(".py", ignoreCase = true) ||
-                                it.endsWith(".js", ignoreCase = true) || it.endsWith(".cpp", ignoreCase = true) ||
-                                it.endsWith(".c", ignoreCase = true) || it.endsWith(".cs", ignoreCase = true) ||
-                                it.endsWith(".rb", ignoreCase = true) || it.endsWith(".go", ignoreCase = true)
-                    } == true) {
-                    FileType.HTML
-                } else {
-                    FileType.TXT
-                }
+                resolveFileTypeFromName(fileName) ?: FileType.TXT
             }
 
             else -> {
-                when {
-                    fileName?.endsWith(".cbz", ignoreCase = true) == true -> FileType.CBZ
-                    fileName?.endsWith(".cbr", ignoreCase = true) == true -> FileType.CBR
-                    fileName?.endsWith(".cb7", ignoreCase = true) == true -> FileType.CB7
-                    fileName?.endsWith(".pdf", ignoreCase = true) == true -> FileType.PDF
-                    fileName?.endsWith(".epub", ignoreCase = true) == true -> FileType.EPUB
-                    fileName?.endsWith(
-                        ".mobi",
-                        ignoreCase = true
-                    ) == true || fileName?.endsWith(
-                        ".azw3",
-                        ignoreCase = true
-                    ) == true || fileName?.endsWith(
-                        ".prc",
-                        ignoreCase = true
-                    ) == true -> FileType.MOBI
-
-                    fileName?.endsWith(
-                        ".md",
-                        ignoreCase = true
-                    ) == true || fileName?.endsWith(
-                        ".markdown",
-                        ignoreCase = true
-                    ) == true -> FileType.MD
-
-                    fileName?.endsWith(".txt", ignoreCase = true) == true -> FileType.TXT
-                    fileName?.endsWith(
-                        ".fb2",
-                        ignoreCase = true
-                    ) == true || fileName?.endsWith(
-                        ".fb2.zip",
-                        ignoreCase = true
-                    ) == true -> FileType.FB2
-                    fileName?.endsWith(
-                        ".html",
-                        ignoreCase = true
-                    ) == true || fileName?.endsWith(
-                        ".xhtml",
-                        ignoreCase = true
-                    ) == true || fileName?.endsWith(
-                        ".htm",
-                        ignoreCase = true
-                    ) == true -> FileType.HTML
-                    fileName?.endsWith(".docx", ignoreCase = true) == true -> FileType.DOCX
-                    fileName?.endsWith(".odt", ignoreCase = true) == true -> FileType.ODT
-                    fileName?.endsWith(".fodt", ignoreCase = true) == true -> FileType.FODT
-                    fileName?.endsWith(".csv", ignoreCase = true) == true ||
-                    fileName?.endsWith(".tsv", ignoreCase = true) == true ||
-                    fileName?.endsWith(".json", ignoreCase = true) == true ||
-                    fileName?.endsWith(".xml", ignoreCase = true) == true ||
-                    fileName?.endsWith(".log", ignoreCase = true) == true ||
-                    fileName?.endsWith(".java", ignoreCase = true) == true ||
-                    fileName?.endsWith(".kt", ignoreCase = true) == true ||
-                    fileName?.endsWith(".py", ignoreCase = true) == true ||
-                    fileName?.endsWith(".js", ignoreCase = true) == true ||
-                    fileName?.endsWith(".cpp", ignoreCase = true) == true ||
-                    fileName?.endsWith(".c", ignoreCase = true) == true ||
-                    fileName?.endsWith(".cs", ignoreCase = true) == true ||
-                    fileName?.endsWith(".rb", ignoreCase = true) == true ||
-                    fileName?.endsWith(".go", ignoreCase = true) == true -> FileType.HTML
-
-                    else -> null
-                }
+                resolveFileTypeFromName(fileName)
             }
         }
     }
@@ -4739,7 +4221,11 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
                     }
                 } else {
                     throw Exception(
-                        "MobiParser returned null. The file might be DRM-protected or invalid."
+                        if (MobiParser.isNativeParserAvailable) {
+                            "MobiParser returned null. The file might be DRM-protected or invalid."
+                        } else {
+                            MobiParser.nativeParserUnavailableMessage()
+                        }
                     )
                 }
             } catch (e: Exception) {
@@ -4945,6 +4431,7 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
     }
 
     fun onRecentFileClicked(item: RecentFileItem) {
+        ReaderPerfLog.d("FileOpen click bookId=${item.bookId} name=${item.displayName}")
         val currentSelection = _internalState.value.contextualActionItems
         if (currentSelection.isNotEmpty()) {
             Timber.d("Toggling selection for: ${item.displayName}")
@@ -5125,6 +4612,7 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
 
     fun setMainScreenPage(page: Int) {
         val sanitizedPage = page.coerceIn(0, 1)
+        if (_internalState.value.mainScreenStartPage == sanitizedPage) return
         _internalState.update { it.copy(mainScreenStartPage = sanitizedPage) }
         persistLibraryLandingState()
     }
@@ -5132,6 +4620,7 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
     fun setLibraryScreenPage(page: Int) {
         val maxLibraryPage = if (BuildConfig.IS_OFFLINE) 2 else 3
         val sanitizedPage = page.coerceIn(0, maxLibraryPage)
+        if (_internalState.value.libraryScreenStartPage == sanitizedPage) return
         _internalState.update {
             it.copy(libraryScreenStartPage = sanitizedPage)
         }
@@ -5701,9 +5190,14 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
         prefs.edit { putString(KEY_APP_CONTRAST_OPTION, option.name) }
     }
 
-    fun setAppTextDimFactor(factor: Float) {
-        _internalState.update { it.copy(appTextDimFactor = factor) }
-        prefs.edit { putFloat(KEY_APP_TEXT_DIM_FACTOR, factor) }
+    fun setAppTextDimFactorLight(factor: Float) {
+        _internalState.update { it.copy(appTextDimFactorLight = factor) }
+        prefs.edit { putFloat(KEY_APP_TEXT_DIM_FACTOR_LIGHT, factor) }
+    }
+
+    fun setAppTextDimFactorDark(factor: Float) {
+        _internalState.update { it.copy(appTextDimFactorDark = factor) }
+        prefs.edit { putFloat(KEY_APP_TEXT_DIM_FACTOR_DARK, factor) }
     }
 
     fun setAppSeedColor(color: androidx.compose.ui.graphics.Color?) {
@@ -5948,6 +5442,8 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
         private const val KEY_APP_CONTRAST_OPTION = "app_contrast_option"
         private const val KEY_APP_SEED_COLOR = "app_seed_color"
         private const val KEY_APP_TEXT_DIM_FACTOR = "app_text_dim_factor"
+        private const val KEY_APP_TEXT_DIM_FACTOR_LIGHT = "app_text_dim_factor_light"
+        private const val KEY_APP_TEXT_DIM_FACTOR_DARK = "app_text_dim_factor_dark"
         private const val KEY_CUSTOM_APP_THEMES = "custom_app_themes"
 
         val SUPPORTED_MIME_TYPES = arrayOf(

app/src/main/java/com/aryan/reader/MetadataExtractionWorker.kt

@@ -2,19 +2,20 @@
 package com.aryan.reader
 
 import android.content.Context
+import android.provider.OpenableColumns
+import android.util.Xml
 import androidx.core.net.toUri
 import androidx.work.CoroutineWorker
 import androidx.work.WorkerParameters
+import com.aryan.reader.data.RecentFileItem
 import com.aryan.reader.data.RecentFilesRepository
-import com.aryan.reader.epub.EpubParser
-import com.aryan.reader.epub.ImportedFileCache
-import com.aryan.reader.epub.MobiParser
-import com.aryan.reader.pdf.PdfCoverGenerator
 import io.legere.pdfiumandroid.PdfiumCore
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
+import org.xmlpull.v1.XmlPullParser
 import timber.log.Timber
 import java.io.File
+import java.util.zip.ZipInputStream
 
 class MetadataExtractionWorker(
     private val appContext: Context,
@@ -22,179 +23,271 @@ class MetadataExtractionWorker(
 ) : CoroutineWorker(appContext, workerParams) {
 
     private val recentFilesRepository = RecentFilesRepository(appContext)
-    private val epubParser = EpubParser(appContext)
-    private val mobiParser = MobiParser(appContext)
-    private val pdfCoverGenerator = PdfCoverGenerator(appContext)
-    private val odtParser = com.aryan.reader.epub.OdtParser(appContext)
 
     companion object {
         const val WORK_NAME = "MetadataExtractionWorker"
+        const val KEY_SOURCE_FOLDER_URI = "key_source_folder_uri"
+        private const val METADATA_DB_BATCH_SIZE = 100
+        private const val METADATA_PROGRESS_LOG_EVERY = 250
     }
 
     override suspend fun doWork(): Result = withContext(Dispatchers.IO) {
+        val workerStart = ReaderPerfLog.nowNanos()
+        val sourceFolderUri = inputData.getString(KEY_SOURCE_FOLDER_URI)
         val prefs = appContext.getSharedPreferences("reader_user_prefs", Context.MODE_PRIVATE)
 
         val hasLegacy = prefs.contains("synced_folder_uri")
         val hasNew = prefs.contains("synced_folders_list_json")
 
         if (!hasLegacy && !hasNew) {
-            Timber.tag("MetadataWorker").w("No folders linked. Stopping.")
+            ReaderPerfLog.d("MetadataWorker skipped: no linked folders")
             return@withContext Result.success()
         }
 
         try {
-            val filesToProcess = recentFilesRepository.getFolderBooksWithoutCovers()
+            val filesToProcess = recentFilesRepository.getFolderBooksNeedingTextMetadata(sourceFolderUri)
 
             if (filesToProcess.isEmpty()) {
+                ReaderPerfLog.d("MetadataWorker skipped: no text metadata pending folder=${sourceFolderUri ?: "ALL"}")
                 return@withContext Result.success()
             }
 
-            Timber.tag("MetadataWorker").i("Starting background metadata extraction for ${filesToProcess.size} books.")
+            ReaderPerfLog.i(
+                "MetadataWorker start mode=text-only books=${filesToProcess.size} folder=${sourceFolderUri ?: "ALL"}"
+            )
+
+            val pendingUpdates = mutableListOf<RecentFileItem>()
+            var processed = 0
+            var updated = 0
+            var failed = 0
+
+            suspend fun flushUpdates() {
+                if (pendingUpdates.isEmpty()) return
+                val flushStart = ReaderPerfLog.nowNanos()
+                recentFilesRepository.updateExtractedMetadata(pendingUpdates)
+                ReaderPerfLog.d(
+                    "MetadataWorker DB flush rows=${pendingUpdates.size} elapsed=${ReaderPerfLog.elapsedMs(flushStart)}ms"
+                )
+                pendingUpdates.clear()
+            }
 
             filesToProcess.forEach { item ->
                 if (isStopped) return@forEach
 
                 if (item.sourceFolderUri == null) return@forEach
 
-                val tempExtractionDir =
-                    if (item.type == FileType.EPUB || item.type == FileType.MOBI || item.type == FileType.ODT || item.type == FileType.FODT) {
-                        ImportedFileCache.createTemporaryBookDir(appContext, item.bookId, "metadata")
-                    } else {
-                        null
-                    }
-
                 try {
                     val uri = item.uriString?.toUri() ?: return@forEach
-                    val type = item.type
-
-                    var coverPath: String? = null
-                    var title: String? = null
-                    var author: String? = null
-
-                    val fileSize = try {
-                        if (uri.scheme == "file") {
-                            uri.path?.let { File(it).length() } ?: 0L
-                        } else {
-                            appContext.contentResolver.query(uri, null, null, null, null)?.use { cursor ->
-                                if (cursor.moveToFirst()) {
-                                    val sizeIndex = cursor.getColumnIndex(android.provider.OpenableColumns.SIZE)
-                                    if (sizeIndex != -1) cursor.getLong(sizeIndex) else 0L
-                                } else 0L
-                            } ?: 0L
-                        }
-                    } catch (e: Exception) {
-                        Timber.tag("MetadataWorker").e(e, "Failed to get file size for ${item.displayName}")
-                        0L
+                    val fileSize = item.fileSize.takeIf { it > 0L } ?: queryFileSize(uri)
+                    val metadata = when (item.type) {
+                        FileType.EPUB -> parseEpubTextMetadata(uri)
+                        FileType.PDF -> parsePdfTextMetadata(uri)
+                        FileType.ODT -> parseZipTextMetadata(uri, "meta.xml")
+                        FileType.FODT -> parseFlatXmlTextMetadata(uri)
+                        FileType.DOCX -> parseZipTextMetadata(uri, "docProps/core.xml")
+                        else -> TextMetadata()
                     }
 
-                    appContext.contentResolver.openInputStream(uri)?.use { inputStream ->
-                        when (type) {
-                            FileType.EPUB -> {
-                                val book = epubParser.createEpubBook(
-                                    inputStream = inputStream,
-                                    bookId = item.bookId,
-                                    originalBookNameHint = item.displayName,
-                                    parseContent = false,
-                                    extractionDirOverride = tempExtractionDir
-                                )
-                                title = book.title.takeIf { it.isNotBlank() && it != "content" }
-                                author = book.author.takeIf { it.isNotBlank() && !it.equals("Unknown", ignoreCase = true) }
-                                book.coverImage?.let { coverPath = recentFilesRepository.saveCoverToCache(it, uri) }
-                            }
-                            FileType.MOBI -> {
-                                val book = mobiParser.createMobiBook(
-                                    inputStream = inputStream,
-                                    bookId = item.bookId,
-                                    originalBookNameHint = item.displayName,
-                                    parseContent = false,
-                                    extractionDirOverride = tempExtractionDir
-                                )
-                                book?.let {
-                                    title = it.title.takeIf { t -> t.isNotBlank() && t != "content" }
-                                    author = it.author.takeIf { a -> a.isNotBlank() && !a.equals("Unknown", ignoreCase = true) }
-                                    it.coverImage?.let { img -> coverPath = recentFilesRepository.saveCoverToCache(img, uri) }
-                                }
-                            }
-                            FileType.PDF -> {
-                                pdfCoverGenerator.generateCover(uri)?.let {
-                                    coverPath = recentFilesRepository.saveCoverToCache(it, uri)
-                                }
-                                title = item.displayName
+                    val title = sanitizeTitle(metadata.title)
+                    val author = sanitizeAuthor(metadata.author)
+                    val sizeChanged = fileSize > 0L && fileSize != item.fileSize
+                    val titleChanged = title != null && title != item.title
+                    val authorChanged = author != null && author != item.author
 
-                                try {
-                                    val pdfiumCore = PdfiumCore(appContext)
-                                    appContext.contentResolver.openFileDescriptor(uri, "r")?.use { pfd ->
-                                        val pdfDocument = pdfiumCore.newDocument(pfd)
-                                        val meta = pdfiumCore.getDocumentMeta(pdfDocument)
-
-                                        val extractedTitle = meta.title
-                                        if (!extractedTitle.isNullOrBlank()) {
-                                            title = extractedTitle
-                                        }
-
-                                        val extractedAuthor = meta.author
-                                        if (!extractedAuthor.isNullOrBlank()) {
-                                            author = extractedAuthor
-                                        }
-
-                                        pdfiumCore.closeDocument(pdfDocument)
-                                    }
-                                } catch (e: Exception) {
-                                    Timber.tag("MetadataWorker").e(e, "Failed to extract PDF metadata using PdfiumCore")
-                                }
-                            }
-                            FileType.ODT, FileType.FODT -> {
-                                val book = odtParser.createOdtBook(
-                                    inputStream = inputStream,
-                                    bookId = item.bookId,
-                                    originalBookNameHint = item.displayName,
-                                    isFlat = type == FileType.FODT,
-                                    parseContent = false,
-                                    extractionDirOverride = tempExtractionDir
-                                )
-                                title = book.title.takeIf { it.isNotBlank() && it != "content" }
-                                author = book.author.takeIf { it.isNotBlank() && !it.equals("Unknown", ignoreCase = true) }
-                                book.coverImage?.let { coverPath = recentFilesRepository.saveCoverToCache(it, uri) }
-                            }
-                            else -> {
-                                title = item.displayName
-                            }
-                        }
-                    }
-
-                    if (coverPath != null || title != null || author != null || fileSize > 0L) {
-                        val updatedItem = item.copy(
-                            coverImagePath = coverPath ?: item.coverImagePath,
-                            title = title ?: item.title ?: item.displayName,
-                            author = author ?: item.author,
-                            fileSize = if (fileSize > 0L) fileSize else item.fileSize
+                    if (!item.folderTextMetadataParsed || sizeChanged || titleChanged || authorChanged) {
+                        pendingUpdates.add(
+                            item.copy(
+                                title = title ?: item.title ?: item.displayName,
+                                author = author ?: item.author,
+                                fileSize = if (fileSize > 0L) fileSize else item.fileSize,
+                                folderTextMetadataParsed = true
+                            )
                         )
-                        recentFilesRepository.addRecentFile(updatedItem)
-                        Timber.tag("MetadataWorker").d("Updated local metadata/size for: ${item.displayName} ($fileSize bytes)")
+                        if (sizeChanged || titleChanged || authorChanged) {
+                            updated++
+                        }
+                        if (pendingUpdates.size >= METADATA_DB_BATCH_SIZE) {
+                            flushUpdates()
+                        }
                     }
 
-                } catch (e: Exception) {
-                    Timber.tag("MetadataWorker").e(e, "Failed to extract metadata for ${item.displayName}")
-                } finally {
-                    try {
-                        if (tempExtractionDir?.exists() == true) {
-                            val deleted = tempExtractionDir.deleteRecursively()
-                            if (deleted) {
-                                Timber.tag("MetadataWorker")
-                                    .d("Cleaned up temporary extraction cache for ${item.bookId}")
-                            }
-                        }
-                    } catch (e: Exception) {
-                        Timber.tag("MetadataWorker")
-                            .e(e, "Failed to clean up temporary extraction cache for ${item.bookId}")
+                    processed++
+                    if (processed % METADATA_PROGRESS_LOG_EVERY == 0) {
+                        ReaderPerfLog.d(
+                            "MetadataWorker progress mode=text-only processed=$processed updated=$updated failed=$failed"
+                        )
                     }
+                } catch (e: Exception) {
+                    failed++
+                    Timber.tag("MetadataWorker").e(e, "Failed text metadata extraction for ${item.displayName}")
                 }
             }
 
+            flushUpdates()
+
+            ReaderPerfLog.i(
+                "MetadataWorker finished mode=text-only processed=$processed updated=$updated failed=$failed " +
+                    "elapsed=${ReaderPerfLog.elapsedMs(workerStart)}ms folder=${sourceFolderUri ?: "ALL"}"
+            )
+
             return@withContext Result.success()
         } catch (e: Exception) {
-            Timber.tag("MetadataWorker").e(e, "Metadata extraction failed")
+            Timber.tag("MetadataWorker").e(e, "Text metadata extraction failed")
             return@withContext Result.failure()
         }
     }
+
+    private fun queryFileSize(uri: android.net.Uri): Long {
+        return try {
+            if (uri.scheme == "file") {
+                uri.path?.let { File(it).length() } ?: 0L
+            } else {
+                appContext.contentResolver.query(uri, null, null, null, null)?.use { cursor ->
+                    if (cursor.moveToFirst()) {
+                        val sizeIndex = cursor.getColumnIndex(OpenableColumns.SIZE)
+                        if (sizeIndex != -1 && !cursor.isNull(sizeIndex)) cursor.getLong(sizeIndex) else 0L
+                    } else {
+                        0L
+                    }
+                } ?: 0L
+            }
+        } catch (e: Exception) {
+            Timber.tag("MetadataWorker").e(e, "Failed to query file size for $uri")
+            0L
+        }
+    }
+
+    private fun parseEpubTextMetadata(uri: android.net.Uri): TextMetadata {
+        val opfEntries = linkedMapOf<String, String>()
+        var containerXml: String? = null
+
+        appContext.contentResolver.openInputStream(uri)?.use { input ->
+            ZipInputStream(input.buffered()).use { zip ->
+                while (true) {
+                    val entry = zip.nextEntry ?: break
+                    if (entry.isDirectory) continue
+                    val name = entry.name
+                    when {
+                        name == "META-INF/container.xml" -> containerXml = zip.readTextEntry()
+                        name.endsWith(".opf", ignoreCase = true) -> opfEntries[name] = zip.readTextEntry()
+                    }
+                    zip.closeEntry()
+                }
+            }
+        }
+
+        val opfPath = containerXml?.let { parseEpubRootfilePath(it) }
+        val opfXml = opfPath?.let { opfEntries[it] } ?: opfEntries.values.firstOrNull()
+        return opfXml?.let { parseXmlTextMetadata(it) } ?: TextMetadata()
+    }
+
+    private fun parseZipTextMetadata(uri: android.net.Uri, targetEntryName: String): TextMetadata {
+        appContext.contentResolver.openInputStream(uri)?.use { input ->
+            ZipInputStream(input.buffered()).use { zip ->
+                while (true) {
+                    val entry = zip.nextEntry ?: break
+                    if (!entry.isDirectory && entry.name == targetEntryName) {
+                        val xml = zip.readTextEntry()
+                        return parseXmlTextMetadata(xml)
+                    }
+                    zip.closeEntry()
+                }
+            }
+        }
+        return TextMetadata()
+    }
+
+    private fun parseFlatXmlTextMetadata(uri: android.net.Uri): TextMetadata {
+        val xml = appContext.contentResolver.openInputStream(uri)?.use { input ->
+            input.bufferedReader(Charsets.UTF_8).use { it.readText() }
+        } ?: return TextMetadata()
+        return parseXmlTextMetadata(xml)
+    }
+
+    private fun parsePdfTextMetadata(uri: android.net.Uri): TextMetadata {
+        return try {
+            val pdfiumCore = PdfiumCore(appContext)
+            appContext.contentResolver.openFileDescriptor(uri, "r")?.use { pfd ->
+                val pdfDocument = pdfiumCore.newDocument(pfd)
+                try {
+                    val meta = pdfiumCore.getDocumentMeta(pdfDocument)
+                    TextMetadata(title = meta.title, author = meta.author)
+                } finally {
+                    pdfiumCore.closeDocument(pdfDocument)
+                }
+            } ?: TextMetadata()
+        } catch (e: Exception) {
+            Timber.tag("MetadataWorker").e(e, "Failed to extract PDF text metadata")
+            TextMetadata()
+        }
+    }
+
+    private fun parseEpubRootfilePath(containerXml: String): String? {
+        val parser = Xml.newPullParser()
+        parser.setFeature(XmlPullParser.FEATURE_PROCESS_NAMESPACES, true)
+        parser.setInput(containerXml.reader())
+
+        var event = parser.eventType
+        while (event != XmlPullParser.END_DOCUMENT) {
+            if (event == XmlPullParser.START_TAG && parser.name.equals("rootfile", ignoreCase = true)) {
+                return parser.getAttributeValue(null, "full-path")?.takeIf { it.isNotBlank() }
+            }
+            event = parser.next()
+        }
+        return null
+    }
+
+    private fun parseXmlTextMetadata(xml: String): TextMetadata {
+        val parser = Xml.newPullParser()
+        parser.setFeature(XmlPullParser.FEATURE_PROCESS_NAMESPACES, true)
+        parser.setInput(xml.reader())
+
+        var title: String? = null
+        var author: String? = null
+        var event = parser.eventType
+
+        while (event != XmlPullParser.END_DOCUMENT) {
+            if (event == XmlPullParser.START_TAG) {
+                val name = parser.name.substringAfter(':').lowercase()
+                when {
+                    title == null && name == "title" -> title = parser.nextTextOrNull()
+                    author == null && (name == "creator" || name == "initial-creator") -> {
+                        author = parser.nextTextOrNull()
+                    }
+                }
+            }
+            event = parser.next()
+        }
+
+        return TextMetadata(title = title, author = author)
+    }
+
+    private fun XmlPullParser.nextTextOrNull(): String? {
+        return try {
+            nextText()?.trim()?.takeIf { it.isNotBlank() }
+        } catch (_: Exception) {
+            null
+        }
+    }
+
+    private fun ZipInputStream.readTextEntry(): String {
+        return String(readBytes(), Charsets.UTF_8)
+    }
+
+    private fun sanitizeTitle(value: String?): String? {
+        return value
+            ?.trim()
+            ?.takeIf { it.isNotBlank() && !it.equals("content", ignoreCase = true) }
+    }
+
+    private fun sanitizeAuthor(value: String?): String? {
+        return value
+            ?.trim()
+            ?.takeIf { it.isNotBlank() && !it.equals("Unknown", ignoreCase = true) }
+    }
+
+    private data class TextMetadata(
+        val title: String? = null,
+        val author: String? = null
+    )
 }

app/src/main/java/com/aryan/reader/NonReaderScreenModels.kt

@@ -0,0 +1,54 @@
+package com.aryan.reader
+
+import com.aryan.reader.data.RecentFileItem
+
+data class HomeScreenModel(
+    val recentFiles: List<RecentFileItem>,
+    val openTabs: List<RecentFileItem>,
+    val selectedItems: Set<RecentFileItem>,
+    val isContextualModeActive: Boolean,
+    val deviceLimitState: DeviceLimitReachedState,
+    val isEmpty: Boolean,
+    val isLibraryEmpty: Boolean
+)
+
+fun ReaderScreenState.toHomeScreenModel(): HomeScreenModel {
+    val homeRecentFiles = recentFiles
+    return HomeScreenModel(
+        recentFiles = homeRecentFiles,
+        openTabs = openTabs,
+        selectedItems = contextualActionItems,
+        isContextualModeActive = contextualActionItems.isNotEmpty(),
+        deviceLimitState = deviceLimitState,
+        isEmpty = homeRecentFiles.isEmpty() && (!isTabsEnabled || openTabs.isEmpty()),
+        isLibraryEmpty = recentFiles.isEmpty()
+    )
+}
+
+data class LibraryScreenModel(
+    val selectedItems: Set<RecentFileItem>,
+    val isContextualModeActive: Boolean,
+    val selectedShelves: Set<String>,
+    val isShelfContextualModeActive: Boolean,
+    val sortOrder: SortOrder,
+    val shelves: List<Shelf>,
+    val rawLibraryFiles: List<RecentFileItem>,
+    val containsFolderItemsInSelection: Boolean,
+    val isSearchActive: Boolean,
+    val searchQuery: String
+)
+
+fun ReaderScreenState.toLibraryScreenModel(): LibraryScreenModel {
+    return LibraryScreenModel(
+        selectedItems = contextualActionItems,
+        isContextualModeActive = contextualActionItems.isNotEmpty(),
+        selectedShelves = contextualActionShelfIds,
+        isShelfContextualModeActive = contextualActionShelfIds.isNotEmpty(),
+        sortOrder = sortOrder,
+        shelves = shelves,
+        rawLibraryFiles = rawLibraryFiles,
+        containsFolderItemsInSelection = contextualActionItems.any { it.sourceFolderUri != null },
+        isSearchActive = isSearchActive,
+        searchQuery = searchQuery
+    )
+}

app/src/main/java/com/aryan/reader/ReaderPerfLog.kt

@@ -0,0 +1,59 @@
+package com.aryan.reader
+
+import timber.log.Timber
+
+object ReaderPerfLog {
+    const val TAG = "ReaderPerf"
+
+    fun nowNanos(): Long = System.nanoTime()
+
+    fun elapsedMs(startNanos: Long): Long = (System.nanoTime() - startNanos) / 1_000_000L
+
+    fun d(message: String) {
+        Timber.tag(TAG).d(message)
+    }
+
+    fun i(message: String) {
+        Timber.tag(TAG).i(message)
+    }
+
+    fun w(message: String) {
+        Timber.tag(TAG).w(message)
+    }
+
+    inline fun <T> measure(
+        name: String,
+        minLogMs: Long = 16L,
+        details: () -> String = { "" },
+        block: () -> T
+    ): T {
+        val start = nowNanos()
+        try {
+            return block()
+        } finally {
+            val elapsed = elapsedMs(start)
+            if (elapsed >= minLogMs) {
+                val extra = details().takeIf { it.isNotBlank() }?.let { " $it" }.orEmpty()
+                d("$name took ${elapsed}ms$extra")
+            }
+        }
+    }
+
+    suspend inline fun <T> measureSuspend(
+        name: String,
+        minLogMs: Long = 16L,
+        details: () -> String = { "" },
+        crossinline block: suspend () -> T
+    ): T {
+        val start = nowNanos()
+        try {
+            return block()
+        } finally {
+            val elapsed = elapsedMs(start)
+            if (elapsed >= minLogMs) {
+                val extra = details().takeIf { it.isNotBlank() }?.let { " $it" }.orEmpty()
+                d("$name took ${elapsed}ms$extra")
+            }
+        }
+    }
+}

app/src/main/java/com/aryan/reader/SharedModelMappers.kt

@@ -0,0 +1,220 @@
+package com.aryan.reader
+
+import com.aryan.reader.data.BookShelfCrossRef
+import com.aryan.reader.data.BookTagCrossRef
+import com.aryan.reader.data.RecentFileItem
+import com.aryan.reader.data.ShelfEntity
+import com.aryan.reader.data.TagEntity
+import com.aryan.reader.shared.AddBooksSource as SharedAddBooksSource
+import com.aryan.reader.shared.AppContrastOption as SharedAppContrastOption
+import com.aryan.reader.shared.AppThemeMode as SharedAppThemeMode
+import com.aryan.reader.shared.BannerMessage as SharedBannerMessage
+import com.aryan.reader.shared.BookItem as SharedBookItem
+import com.aryan.reader.shared.BookShelfRef as SharedBookShelfRef
+import com.aryan.reader.shared.CustomAppTheme as SharedCustomAppTheme
+import com.aryan.reader.shared.FileType as SharedFileType
+import com.aryan.reader.shared.LibraryFilters as SharedLibraryFilters
+import com.aryan.reader.shared.ReadStatusFilter as SharedReadStatusFilter
+import com.aryan.reader.shared.RenderMode as SharedRenderMode
+import com.aryan.reader.shared.SharedLibraryProjectionInput
+import com.aryan.reader.shared.SharedReaderScreenState
+import com.aryan.reader.shared.ShelfRecord
+import com.aryan.reader.shared.SortOrder as SharedSortOrder
+import com.aryan.reader.shared.SyncedFolder as SharedSyncedFolder
+import com.aryan.reader.shared.Tag as SharedTag
+
+fun RecentFileItem.toSharedBookItem(): SharedBookItem {
+    return SharedBookItem(
+        id = bookId,
+        path = uriString,
+        type = type.toSharedFileType(),
+        displayName = customName ?: displayName,
+        timestamp = timestamp,
+        title = title,
+        author = author,
+        progressPercentage = progressPercentage,
+        isRecent = isRecent,
+        fileSize = fileSize,
+        sourceFolder = sourceFolderUri,
+        seriesName = seriesName,
+        seriesIndex = seriesIndex,
+        tags = tags.map { it.toSharedTag() }
+    )
+}
+
+fun TagEntity.toSharedTag(): SharedTag {
+    return SharedTag(
+        id = id,
+        name = name,
+        color = color
+    )
+}
+
+fun ShelfEntity.toSharedShelfRecord(): ShelfRecord {
+    return ShelfRecord(
+        id = id,
+        name = name,
+        isSmart = isSmart,
+        smartRulesJson = smartRulesJson
+    )
+}
+
+fun BookShelfCrossRef.toSharedBookShelfRef(): SharedBookShelfRef {
+    return SharedBookShelfRef(
+        bookId = bookId,
+        shelfId = shelfId,
+        addedAt = addedAt
+    )
+}
+
+fun ReaderScreenState.toSharedReaderScreenState(
+    rawBooks: List<RecentFileItem> = rawLibraryFiles,
+    dbTags: List<TagEntity> = allTags
+): SharedReaderScreenState {
+    return SharedReaderScreenState(
+        selectedBookId = selectedBookId,
+        selectedUriString = selectedPdfUri?.toString() ?: selectedEpubUri?.toString(),
+        selectedFileType = selectedFileType?.toSharedFileType(),
+        isLoading = isLoading,
+        errorMessage = errorMessage,
+        renderMode = renderMode.toSharedRenderMode(),
+        sortOrder = sortOrder.toSharedSortOrder(),
+        viewingShelfId = viewingShelfId,
+        isAddingBooksToShelf = isAddingBooksToShelf,
+        showCreateShelfDialog = showCreateShelfDialog,
+        mainScreenStartPage = mainScreenStartPage,
+        libraryScreenStartPage = libraryScreenStartPage,
+        showRenameShelfDialogFor = showRenameShelfDialogFor,
+        showDeleteShelfDialogFor = showDeleteShelfDialogFor,
+        addBooksSource = addBooksSource.toSharedAddBooksSource(),
+        booksSelectedForAdding = booksSelectedForAdding,
+        selectedBookIds = contextualActionItems.mapTo(mutableSetOf()) { it.bookId },
+        selectedShelfIds = contextualActionShelfIds,
+        isProUser = isProUser,
+        credits = credits,
+        isSyncEnabled = isSyncEnabled,
+        isFolderSyncEnabled = isFolderSyncEnabled,
+        bannerMessage = bannerMessage?.toSharedBannerMessage(),
+        downloadingBookIds = downloadingBookIds,
+        uploadingBookIds = uploadingBookIds,
+        syncedFolders = syncedFolders.map { it.toSharedSyncedFolder() },
+        lastFolderScanTime = lastFolderScanTime,
+        hasUnreadFeedback = hasUnreadFeedback,
+        searchQuery = searchQuery,
+        isSearchActive = isSearchActive,
+        isRefreshing = isRefreshing,
+        reflowProgress = reflowProgress,
+        recentBooks = recentFiles.map { it.toSharedBookItem() },
+        libraryBooks = allRecentFiles.map { it.toSharedBookItem() },
+        rawLibraryBooks = rawBooks.map { it.toSharedBookItem() },
+        pinnedHomeBookIds = pinnedHomeBookIds,
+        pinnedLibraryBookIds = pinnedLibraryBookIds,
+        libraryFilters = libraryFilters.toSharedLibraryFilters(),
+        recentFilesLimit = recentFilesLimit,
+        isTabsEnabled = isTabsEnabled,
+        openTabIds = openTabIds,
+        openTabs = openTabs.map { it.toSharedBookItem() },
+        activeTabBookId = activeTabBookId,
+        showExternalFileSavePromptFor = showExternalFileSavePromptFor,
+        externalFileBehavior = externalFileBehavior,
+        useStrictFileFilter = useStrictFileFilter,
+        appThemeMode = appThemeMode.toSharedAppThemeMode(),
+        appContrastOption = appContrastOption.toSharedAppContrastOption(),
+        appTextDimFactorLight = appTextDimFactorLight,
+        appTextDimFactorDark = appTextDimFactorDark,
+        appSeedColor = appSeedColor,
+        customAppThemes = customAppThemes.map { it.toSharedCustomAppTheme() },
+        allTags = dbTags.map { it.toSharedTag() },
+        showTagSelectionDialogFor = showTagSelectionDialogFor
+    )
+}
+
+fun ReaderScreenState.toSharedLibraryProjectionInput(
+    recentFilesFromDb: List<RecentFileItem>,
+    dbShelves: List<ShelfEntity>,
+    shelfRefs: List<BookShelfCrossRef>,
+    dbTags: List<TagEntity>,
+    tagRefs: List<BookTagCrossRef>
+): SharedLibraryProjectionInput {
+    val tagsById = dbTags.associateBy { it.id }
+    val bookTagsMap = tagRefs.groupBy { it.bookId }.mapValues { entry ->
+        entry.value.mapNotNull { tagsById[it.tagId] }
+    }
+    val taggedBooks = recentFilesFromDb.map { item ->
+        item.copy(tags = bookTagsMap[item.bookId].orEmpty())
+    }
+    return SharedLibraryProjectionInput(
+        state = toSharedReaderScreenState(
+            rawBooks = taggedBooks,
+            dbTags = dbTags
+        ),
+        booksFromStore = taggedBooks
+            .filterNot { it.bookId.endsWith("_reflow") }
+            .map { it.toSharedBookItem() },
+        shelfRecords = dbShelves.map { it.toSharedShelfRecord() },
+        shelfRefs = shelfRefs.map { it.toSharedBookShelfRef() },
+        tags = dbTags.map { it.toSharedTag() }
+    )
+}
+
+fun FileType.toSharedFileType(): SharedFileType {
+    return runCatching { SharedFileType.valueOf(name) }.getOrDefault(SharedFileType.UNKNOWN)
+}
+
+private fun RenderMode.toSharedRenderMode(): SharedRenderMode {
+    return SharedRenderMode.valueOf(name)
+}
+
+private fun AddBooksSource.toSharedAddBooksSource(): SharedAddBooksSource {
+    return SharedAddBooksSource.valueOf(name)
+}
+
+private fun SortOrder.toSharedSortOrder(): SharedSortOrder {
+    return SharedSortOrder.valueOf(name)
+}
+
+private fun ReadStatusFilter.toSharedReadStatusFilter(): SharedReadStatusFilter {
+    return SharedReadStatusFilter.valueOf(name)
+}
+
+private fun LibraryFilters.toSharedLibraryFilters(): SharedLibraryFilters {
+    return SharedLibraryFilters(
+        fileTypes = fileTypes.mapTo(mutableSetOf()) { it.toSharedFileType() },
+        sourceFolders = sourceFolders,
+        readStatus = readStatus.toSharedReadStatusFilter(),
+        tagIds = tagIds
+    )
+}
+
+private fun SyncedFolder.toSharedSyncedFolder(): SharedSyncedFolder {
+    return SharedSyncedFolder(
+        uriString = uriString,
+        name = name,
+        lastScanTime = lastScanTime,
+        allowedFileTypes = allowedFileTypes.mapTo(mutableSetOf()) { it.toSharedFileType() }
+    )
+}
+
+private fun BannerMessage.toSharedBannerMessage(): SharedBannerMessage {
+    return SharedBannerMessage(
+        message = message,
+        isError = isError,
+        isPersistent = isPersistent
+    )
+}
+
+private fun AppThemeMode.toSharedAppThemeMode(): SharedAppThemeMode {
+    return SharedAppThemeMode.valueOf(name)
+}
+
+private fun AppContrastOption.toSharedAppContrastOption(): SharedAppContrastOption {
+    return SharedAppContrastOption.valueOf(name)
+}
+
+private fun CustomAppTheme.toSharedCustomAppTheme(): SharedCustomAppTheme {
+    return SharedCustomAppTheme(
+        id = id,
+        name = name,
+        seedColor = seedColor
+    )
+}

app/src/main/java/com/aryan/reader/UiLabelResources.kt

@@ -0,0 +1,42 @@
+package com.aryan.reader
+
+import androidx.annotation.StringRes
+
+val AddBooksSource.labelRes: Int
+    @StringRes get() = when (this) {
+        AddBooksSource.UNSHELVED -> R.string.add_books_source_unshelved
+        AddBooksSource.ALL_BOOKS -> R.string.add_books_source_all_books
+    }
+
+val AppThemeMode.labelRes: Int
+    @StringRes get() = when (this) {
+        AppThemeMode.SYSTEM -> R.string.app_theme_mode_system
+        AppThemeMode.LIGHT -> R.string.app_theme_mode_light
+        AppThemeMode.DARK -> R.string.app_theme_mode_dark
+    }
+
+val AppContrastOption.labelRes: Int
+    @StringRes get() = when (this) {
+        AppContrastOption.STANDARD -> R.string.app_contrast_standard
+        AppContrastOption.MEDIUM -> R.string.app_contrast_medium
+        AppContrastOption.HIGH -> R.string.app_contrast_high
+    }
+
+val SortOrder.labelRes: Int
+    @StringRes get() = when (this) {
+        SortOrder.RECENT -> R.string.sort_recent
+        SortOrder.TITLE_ASC -> R.string.sort_title_az
+        SortOrder.AUTHOR_ASC -> R.string.sort_author_az
+        SortOrder.PERCENT_ASC -> R.string.sort_percent_asc
+        SortOrder.PERCENT_DESC -> R.string.sort_percent_desc
+        SortOrder.SIZE_ASC -> R.string.sort_size_smallest
+        SortOrder.SIZE_DESC -> R.string.sort_size_biggest
+    }
+
+val ReadStatusFilter.labelRes: Int
+    @StringRes get() = when (this) {
+        ReadStatusFilter.ALL -> R.string.read_status_all
+        ReadStatusFilter.UNREAD -> R.string.read_status_unread
+        ReadStatusFilter.IN_PROGRESS -> R.string.read_status_in_progress
+        ReadStatusFilter.COMPLETED -> R.string.read_status_completed
+    }

app/src/main/java/com/aryan/reader/data/AppDatabase.kt

@@ -36,7 +36,7 @@ import androidx.sqlite.db.SupportSQLiteDatabase
         TagEntity::class,
         BookTagCrossRef::class
     ],
-    version = 18,
+    version = 19,
     exportSchema = false
 )
 @TypeConverters(FileTypeConverter::class)
@@ -251,6 +251,12 @@ abstract class AppDatabase : RoomDatabase() {
             }
         }
 
+        val MIGRATION_18_19 = object : Migration(18, 19) {
+            override fun migrate(db: SupportSQLiteDatabase) {
+                db.execSQL("ALTER TABLE recent_files ADD COLUMN folderTextMetadataParsed INTEGER NOT NULL DEFAULT 0")
+            }
+        }
+
         fun getDatabase(context: Context): AppDatabase {
             return INSTANCE ?: synchronized(this) {
                 val instance = Room.databaseBuilder(
@@ -263,7 +269,7 @@ abstract class AppDatabase : RoomDatabase() {
                         MIGRATION_5_6, MIGRATION_6_7, MIGRATION_7_8, MIGRATION_8_9,
                         MIGRATION_9_10, MIGRATION_10_11, MIGRATION_11_12,
                         MIGRATION_12_13, MIGRATION_13_14, MIGRATION_14_15, MIGRATION_15_16,
-                        MIGRATION_16_17, MIGRATION_17_18
+                        MIGRATION_16_17, MIGRATION_17_18, MIGRATION_18_19
                     )
                     .fallbackToDestructiveMigration(false)
                     .build()

app/src/main/java/com/aryan/reader/data/LocalSyncUtils.kt

@@ -6,6 +6,7 @@ import android.net.Uri
 import android.os.Environment
 import android.provider.DocumentsContract
 import androidx.documentfile.provider.DocumentFile
+import com.aryan.reader.ReaderPerfLog
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
 import org.json.JSONObject
@@ -16,6 +17,116 @@ object LocalSyncUtils {
     private const val ANNOTATION_SUFFIX = "_annotations"
     private const val SYNC_SUBFOLDER_NAME = "EpistemeSyncData"
 
+    private data class SyncFileEntry(
+        val name: String,
+        val uri: Uri
+    )
+
+    private fun syncSubfolderDocId(rootDocId: String): String {
+        return if (rootDocId.endsWith("/$SYNC_SUBFOLDER_NAME")) {
+            rootDocId
+        } else if (rootDocId.endsWith(":")) {
+            rootDocId + SYNC_SUBFOLDER_NAME
+        } else {
+            "$rootDocId/$SYNC_SUBFOLDER_NAME"
+        }
+    }
+
+    private fun querySyncSubfolderFiles(context: Context, sourceFolderUri: Uri): List<SyncFileEntry> {
+        val start = ReaderPerfLog.nowNanos()
+        val resolver = context.contentResolver
+        val rootDocId = try {
+            DocumentsContract.getTreeDocumentId(sourceFolderUri)
+        } catch (_: Exception) {
+            ReaderPerfLog.w("LocalSync direct query skipped: invalid tree uri=$sourceFolderUri")
+            return emptyList()
+        }
+        val syncDocId = syncSubfolderDocId(rootDocId)
+        val syncDirUri = DocumentsContract.buildDocumentUriUsingTree(sourceFolderUri, syncDocId)
+        val documentProjection = arrayOf(DocumentsContract.Document.COLUMN_MIME_TYPE)
+        val isSyncDir = try {
+            resolver.query(syncDirUri, documentProjection, null, null, null)?.use { cursor ->
+                cursor.moveToFirst() &&
+                    cursor.getString(0) == DocumentsContract.Document.MIME_TYPE_DIR
+            } == true
+        } catch (_: Exception) {
+            false
+        }
+
+        if (!isSyncDir) {
+            ReaderPerfLog.d(
+                "LocalSync direct query sync dir missing rootDocId=$rootDocId syncDocId=$syncDocId"
+            )
+            return querySyncSubfolderFilesFallback(context, sourceFolderUri, "missing-direct-sync-dir")
+        }
+
+        val childrenUri = DocumentsContract.buildChildDocumentsUriUsingTree(sourceFolderUri, syncDocId)
+        val projection = arrayOf(
+            DocumentsContract.Document.COLUMN_DOCUMENT_ID,
+            DocumentsContract.Document.COLUMN_DISPLAY_NAME,
+            DocumentsContract.Document.COLUMN_MIME_TYPE
+        )
+        val entries = mutableListOf<SyncFileEntry>()
+        try {
+            resolver.query(childrenUri, projection, null, null, null)?.use { cursor ->
+                val idCol = cursor.getColumnIndexOrThrow(DocumentsContract.Document.COLUMN_DOCUMENT_ID)
+                val nameCol = cursor.getColumnIndexOrThrow(DocumentsContract.Document.COLUMN_DISPLAY_NAME)
+                val mimeCol = cursor.getColumnIndexOrThrow(DocumentsContract.Document.COLUMN_MIME_TYPE)
+                while (cursor.moveToNext()) {
+                    val mimeType = cursor.getString(mimeCol)
+                    if (mimeType == DocumentsContract.Document.MIME_TYPE_DIR) continue
+                    val name = cursor.getString(nameCol) ?: continue
+                    val docId = cursor.getString(idCol) ?: continue
+                    entries.add(
+                        SyncFileEntry(
+                            name = name,
+                            uri = DocumentsContract.buildDocumentUriUsingTree(sourceFolderUri, docId)
+                        )
+                    )
+                }
+            }
+        } catch (e: Exception) {
+            Timber.tag(TAG).e(e, "Failed to query sync subfolder directly")
+            return querySyncSubfolderFilesFallback(context, sourceFolderUri, "direct-query-error")
+        }
+        ReaderPerfLog.d(
+            "LocalSync direct query files=${entries.size} elapsed=${ReaderPerfLog.elapsedMs(start)}ms syncDocId=$syncDocId"
+        )
+        return entries
+    }
+
+    private fun querySyncSubfolderFilesFallback(
+        context: Context,
+        sourceFolderUri: Uri,
+        reason: String
+    ): List<SyncFileEntry> {
+        val start = ReaderPerfLog.nowNanos()
+        return try {
+            val rootTree = DocumentFile.fromTreeUri(context, sourceFolderUri)
+            val syncDir = rootTree?.findFile(SYNC_SUBFOLDER_NAME)
+            if (syncDir == null || !syncDir.isDirectory) {
+                ReaderPerfLog.w("LocalSync fallback query found no sync dir reason=$reason uri=$sourceFolderUri")
+                emptyList()
+            } else {
+                val entries = syncDir.listFiles()
+                    .asSequence()
+                    .filter { it.isFile }
+                    .mapNotNull { file ->
+                        val name = file.name ?: return@mapNotNull null
+                        SyncFileEntry(name = name, uri = file.uri)
+                    }
+                    .toList()
+                ReaderPerfLog.d(
+                    "LocalSync fallback query files=${entries.size} elapsed=${ReaderPerfLog.elapsedMs(start)}ms reason=$reason"
+                )
+                entries
+            }
+        } catch (e: Exception) {
+            Timber.tag(TAG).e(e, "Failed to query sync subfolder fallback")
+            emptyList()
+        }
+    }
+
     private fun getOrCreateSyncDir(rootTree: DocumentFile): DocumentFile? {
         val existing = rootTree.findFile(SYNC_SUBFOLDER_NAME)
         if (existing != null && existing.isDirectory) return existing
@@ -209,22 +320,22 @@ object LocalSyncUtils {
 
     suspend fun preloadAnnotationSidecars(
         context: Context,
-        rootTree: DocumentFile
+        sourceFolderUri: Uri
     ): Map<String, Pair<Long, String>> = withContext(Dispatchers.IO) {
         val results = mutableMapOf<String, Pair<Long, String>>()
 
         try {
-            val syncDir = rootTree.findFile(SYNC_SUBFOLDER_NAME)
-            if (syncDir == null || !syncDir.isDirectory) return@withContext results
-            val bookIds = syncDir.listFiles()
-                .mapNotNull { extractAnnotationBookId(it.name) }
-                .toSet()
-
-            for (bookId in bookIds) {
-                val best = resolveAndCleanAnnotationConflicts(context, syncDir, bookId)
-                if (best != null) {
-                    results[bookId] = best
+            val groupedFiles = querySyncSubfolderFiles(context, sourceFolderUri)
+                .filter { file ->
+                    val name = file.name
+                    extractAnnotationBookId(name) != null &&
+                        !name.contains(".syncthing.")
                 }
+                .groupBy { file -> extractAnnotationBookId(file.name).orEmpty() }
+
+            for ((bookId, files) in groupedFiles) {
+                val best = resolveAnnotationConflictsReadOnly(context, bookId, files)
+                if (best != null) results[bookId] = best
             }
         } catch (e: Exception) {
             Timber.tag("FolderAnnotationSync").e(e, "Error preloading annotation sidecars")
@@ -233,6 +344,44 @@ object LocalSyncUtils {
         return@withContext results
     }
 
+    private fun resolveAnnotationConflictsReadOnly(
+        context: Context,
+        bookId: String,
+        files: List<SyncFileEntry>
+    ): Pair<Long, String>? {
+        val basePattern = ".${bookId}${ANNOTATION_SUFFIX}"
+        val legacyPattern = "${bookId}${ANNOTATION_SUFFIX}"
+        var bestTs = -1L
+        var bestData: String? = null
+
+        for (file in files) {
+            val name = file.name
+            if (!((name.startsWith(basePattern) || name.startsWith(legacyPattern)) &&
+                    name.endsWith(".json") &&
+                    !name.endsWith(".tmp") &&
+                    !name.contains(".syncthing."))
+            ) {
+                continue
+            }
+            try {
+                val content = context.contentResolver.openInputStream(file.uri)?.use {
+                    it.bufferedReader().readText()
+                } ?: continue
+                val json = JSONObject(content)
+                val ts = json.optLong("timestamp", 0L)
+                val data = json.optJSONObject("data")?.toString()
+                if (data != null && ts > bestTs) {
+                    bestTs = ts
+                    bestData = data
+                }
+            } catch (e: Exception) {
+                Timber.tag("FolderAnnotationSync").e(e, "Error parsing annotation sidecar: $name")
+            }
+        }
+
+        return bestData?.let { bestTs to it }
+    }
+
     suspend fun getAnnotationSidecar(
         context: Context,
         sourceFolderUri: Uri,
@@ -253,12 +402,13 @@ object LocalSyncUtils {
     private fun resolveAndCleanAnnotationConflicts(
         context: Context,
         syncDir: DocumentFile,
-        bookId: String
+        bookId: String,
+        knownFiles: List<DocumentFile>? = null
     ): Pair<Long, String>? {
         val basePattern = ".${bookId}${ANNOTATION_SUFFIX}"
         val legacyPattern = "${bookId}${ANNOTATION_SUFFIX}"
 
-        val allFiles = syncDir.listFiles()
+        val allFiles = knownFiles ?: syncDir.listFiles().asList()
 
         val candidates = allFiles.filter { file ->
             val name = file.name ?: ""
@@ -475,21 +625,17 @@ object LocalSyncUtils {
         val finalResults = mutableMapOf<String, FolderBookMetadata>()
 
         try {
-            val rootTree = DocumentFile.fromTreeUri(context, sourceFolderUri) ?: return@withContext finalResults
-            val syncDir = rootTree.findFile(SYNC_SUBFOLDER_NAME)
-            if (syncDir == null || !syncDir.isDirectory) return@withContext finalResults
-            val allFiles = syncDir.listFiles()
-
+            val allFiles = querySyncSubfolderFiles(context, sourceFolderUri)
             val groupedFiles = allFiles
                 .filter {
-                    val name = it.name ?: ""
+                    val name = it.name
                     (name.endsWith(".json") || name.contains(".sync-conflict")) &&
                             !name.contains(ANNOTATION_SUFFIX) &&
                             !name.endsWith(".tmp") &&
                             !name.contains(".syncthing.")
                 }
                 .groupBy { file ->
-                    var name = file.name ?: ""
+                    var name = file.name
                     if (name.startsWith(".")) name = name.substring(1)
                     if (name.contains(".sync-conflict")) {
                         name.substringBefore(".sync-conflict")
@@ -499,17 +645,47 @@ object LocalSyncUtils {
                 }
 
             groupedFiles.forEach { (bookId, files) ->
-                val winner = resolveAndCleanConflicts(context, files, bookId)
+                val winner = resolveMetadataConflictsReadOnly(context, files, bookId)
                 if (winner != null) {
                     finalResults[bookId] = winner
                 }
             }
 
-            Timber.tag(TAG).d("getAllFolderMetadata: Consolidated ${groupedFiles.size} book records from root.")
+            Timber.tag(TAG).d("getAllFolderMetadata: Read ${finalResults.size}/${groupedFiles.size} book records from sync data.")
+            ReaderPerfLog.d(
+                "LocalSync metadata read files=${allFiles.size} groups=${groupedFiles.size} records=${finalResults.size}"
+            )
 
         } catch (e: Exception) {
-            Timber.tag(TAG).e(e, "Error scanning root folder for metadata")
+            Timber.tag(TAG).e(e, "Error scanning sync data folder for metadata")
+            ReaderPerfLog.w("LocalSync metadata read failed uri=$sourceFolderUri")
         }
         return@withContext finalResults
     }
+
+    private fun resolveMetadataConflictsReadOnly(
+        context: Context,
+        files: List<SyncFileEntry>,
+        bookId: String
+    ): FolderBookMetadata? {
+        var bestMeta: FolderBookMetadata? = null
+        for (file in files) {
+            try {
+                val jsonString = context.contentResolver.openInputStream(file.uri)?.use { input ->
+                    input.bufferedReader().use { it.readText() }
+                }
+                if (jsonString != null) {
+                    val meta = FolderBookMetadata.fromJsonString(jsonString)
+                    if (meta.bookId == bookId &&
+                        (bestMeta == null || meta.lastModifiedTimestamp > bestMeta!!.lastModifiedTimestamp)
+                    ) {
+                        bestMeta = meta
+                    }
+                }
+            } catch (e: Exception) {
+                Timber.tag(TAG).e(e, "Failed to parse metadata sidecar: ${file.name}")
+            }
+        }
+        return bestMeta
+    }
 }

app/src/main/java/com/aryan/reader/data/RecentFileDao.kt

@@ -90,8 +90,59 @@ interface RecentFileDao {
     @Query("UPDATE recent_files SET isRecent = 0, lastModifiedTimestamp = :timestamp WHERE bookId IN (:bookIds)")
     suspend fun markAsNotRecent(bookIds: List<String>, timestamp: Long)
 
-    @Query("SELECT * FROM recent_files WHERE sourceFolderUri IS NOT NULL AND coverImagePath IS NULL AND isDeleted = 0")
-    suspend fun getFolderBooksWithoutCovers(): List<RecentFileEntity>
+    @Query("""
+        SELECT * FROM recent_files
+        WHERE sourceFolderUri IS NOT NULL
+        AND isDeleted = 0
+        AND type IN ('PDF', 'EPUB', 'ODT', 'FODT', 'DOCX')
+        AND folderTextMetadataParsed = 0
+    """)
+    suspend fun getFolderBooksNeedingTextMetadata(): List<RecentFileEntity>
+
+    @Query("""
+        SELECT * FROM recent_files
+        WHERE sourceFolderUri = :sourceFolderUri
+        AND isDeleted = 0
+        AND type IN ('PDF', 'EPUB', 'ODT', 'FODT', 'DOCX')
+        AND folderTextMetadataParsed = 0
+    """)
+    suspend fun getFolderBooksNeedingTextMetadata(sourceFolderUri: String): List<RecentFileEntity>
+
+    @Query("""
+        SELECT COUNT(*) FROM recent_files
+        WHERE sourceFolderUri IS NOT NULL
+        AND isDeleted = 0
+        AND type IN ('PDF', 'EPUB', 'ODT', 'FODT', 'DOCX')
+        AND folderTextMetadataParsed = 0
+    """)
+    suspend fun countFolderBooksNeedingTextMetadata(): Int
+
+    @Query("""
+        SELECT COUNT(*) FROM recent_files
+        WHERE sourceFolderUri = :sourceFolderUri
+        AND isDeleted = 0
+        AND type IN ('PDF', 'EPUB', 'ODT', 'FODT', 'DOCX')
+        AND folderTextMetadataParsed = 0
+    """)
+    suspend fun countFolderBooksNeedingTextMetadata(sourceFolderUri: String): Int
+
+    @Query("""
+        UPDATE recent_files
+        SET
+            coverImagePath = COALESCE(:coverImagePath, coverImagePath),
+            title = COALESCE(:title, title),
+            author = COALESCE(:author, author),
+            fileSize = CASE WHEN :fileSize > 0 THEN :fileSize ELSE fileSize END,
+            folderTextMetadataParsed = 1
+        WHERE bookId = :bookId
+    """)
+    suspend fun updateExtractedMetadata(
+        bookId: String,
+        coverImagePath: String?,
+        title: String?,
+        author: String?,
+        fileSize: Long
+    )
 
     @Query("UPDATE recent_files SET sourceFolderUri = NULL WHERE sourceFolderUri IS NOT NULL")
     suspend fun detachAllFolderBooks()

app/src/main/java/com/aryan/reader/data/RecentFileEntity.kt

@@ -54,7 +54,8 @@ data class RecentFileEntity(
     @ColumnInfo(name = "fileSize", defaultValue = "0") val fileSize: Long,
     @ColumnInfo(defaultValue = "NULL") val seriesName: String?,
     @ColumnInfo(defaultValue = "NULL") val seriesIndex: Double?,
-    @ColumnInfo(defaultValue = "NULL") val description: String?
+    @ColumnInfo(defaultValue = "NULL") val description: String?,
+    @ColumnInfo(defaultValue = "0") val folderTextMetadataParsed: Boolean
 )
 
 data class RecentFileSummary(

app/src/main/java/com/aryan/reader/data/RecentFileItem.kt

@@ -19,9 +19,7 @@
  */
 package com.aryan.reader.data
 
-import android.net.Uri
 import com.aryan.reader.FileType
-import androidx.core.net.toUri
 
 data class RecentFileItem(
     val bookId: String,
@@ -51,10 +49,9 @@ data class RecentFileItem(
     val seriesName: String? = null,
     val seriesIndex: Double? = null,
     val description: String? = null,
+    val folderTextMetadataParsed: Boolean = false,
     val tags: List<TagEntity> = emptyList()
-) {
-    fun getUri(): Uri? = uriString?.toUri()
-}
+)
 
 fun RecentFileEntity.toRecentFileItem(): RecentFileItem {
     return RecentFileItem(
@@ -84,7 +81,8 @@ fun RecentFileEntity.toRecentFileItem(): RecentFileItem {
         fileSize = this.fileSize,
         seriesName = this.seriesName,
         seriesIndex = this.seriesIndex,
-        description = this.description
+        description = this.description,
+        folderTextMetadataParsed = this.folderTextMetadataParsed
     )
 }
 
@@ -116,7 +114,8 @@ fun RecentFileItem.toRecentFileEntity(): RecentFileEntity {
         fileSize = this.fileSize,
         seriesName = this.seriesName,
         seriesIndex = this.seriesIndex,
-        description = this.description
+        description = this.description,
+        folderTextMetadataParsed = this.folderTextMetadataParsed
     )
 }
 

app/src/main/java/com/aryan/reader/data/RecentFileItemAndroid.kt

@@ -0,0 +1,6 @@
+package com.aryan.reader.data
+
+import android.net.Uri
+import androidx.core.net.toUri
+
+fun RecentFileItem.getUri(): Uri? = uriString?.toUri()

app/src/main/java/com/aryan/reader/data/RecentFilesRepository.kt

@@ -24,6 +24,7 @@ import android.content.Context
 import android.graphics.Bitmap
 import android.net.Uri
 import androidx.core.net.toUri
+import com.aryan.reader.ReaderPerfLog
 import timber.log.Timber
 import com.aryan.reader.BookImporter
 import com.aryan.reader.paginatedreader.Locator
@@ -33,6 +34,7 @@ import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.withContext
+import androidx.room.withTransaction
 import java.io.File
 import java.io.FileOutputStream
 import com.aryan.reader.pdf.data.PdfAnnotationRepository
@@ -47,7 +49,8 @@ private const val COVER_CACHE_DIR = "cover_cache"
 
 class RecentFilesRepository(private val context: Context) {
 
-    private val recentFileDao = AppDatabase.getDatabase(context).recentFileDao()
+    private val database = AppDatabase.getDatabase(context)
+    private val recentFileDao = database.recentFileDao()
     private val coverCacheDir = File(context.filesDir, COVER_CACHE_DIR)
     private val bookImporter = BookImporter(context)
 
@@ -57,10 +60,10 @@ class RecentFilesRepository(private val context: Context) {
     private val pdfTextBoxRepository = PdfTextBoxRepository(context)
     private val pdfHighlightRepository = com.aryan.reader.pdf.data.PdfHighlightRepository(context)
 
-    val activeShelvesFlow = AppDatabase.getDatabase(context).shelfDao().getAllActiveShelves()
-    val shelfCrossRefsFlow = AppDatabase.getDatabase(context).shelfDao().getAllBookShelfCrossRefs()
-    val tagsFlow = AppDatabase.getDatabase(context).tagDao().getAllTags()
-    val tagCrossRefsFlow = AppDatabase.getDatabase(context).tagDao().getAllBookTagCrossRefs()
+    val activeShelvesFlow = database.shelfDao().getAllActiveShelves()
+    val shelfCrossRefsFlow = database.shelfDao().getAllBookShelfCrossRefs()
+    val tagsFlow = database.tagDao().getAllTags()
+    val tagCrossRefsFlow = database.tagDao().getAllBookTagCrossRefs()
 
     init {
         if (!coverCacheDir.exists()) {
@@ -184,7 +187,8 @@ class RecentFilesRepository(private val context: Context) {
                 fileSize = if (item.fileSize > 0) item.fileSize else existingItem.fileSize,
                 seriesName = item.seriesName ?: existingItem.seriesName,
                 seriesIndex = item.seriesIndex ?: existingItem.seriesIndex,
-                description = item.description ?: existingItem.description
+                description = item.description ?: existingItem.description,
+                folderTextMetadataParsed = item.folderTextMetadataParsed || existingItem.folderTextMetadataParsed
             )
         } else {
             item.toRecentFileEntity()
@@ -355,12 +359,25 @@ class RecentFilesRepository(private val context: Context) {
     }
 
     suspend fun deleteFilesBySourceFolder(folderUriString: String) = withContext(Dispatchers.IO) {
-        val filesToRemove = getFilesBySourceFolder(folderUriString)
-        if (filesToRemove.isNotEmpty()) {
-            Timber.d("DeleteDebug: Cascading deletion for ${filesToRemove.size} files from folder.")
-            deleteFilePermanently(filesToRemove.map { it.bookId })
-        } else {
-            recentFileDao.deleteFilesBySourceFolder(folderUriString)
+        val start = ReaderPerfLog.nowNanos()
+        val filesToRemove = recentFileDao.getFilesBySourceFolder(folderUriString)
+        recentFileDao.deleteFilesBySourceFolder(folderUriString)
+        ReaderPerfLog.i(
+            "FolderRemove db delete books=${filesToRemove.size} elapsed=${ReaderPerfLog.elapsedMs(start)}ms folder=$folderUriString"
+        )
+
+        filesToRemove.forEach { item ->
+            item.coverImagePath?.let { deleteCachedCover(it) }
+            try {
+                pdfAnnotationRepository.getAnnotationFileForSync(item.bookId)?.delete()
+                pdfRichTextRepository.getFileForSync(item.bookId).delete()
+                pageLayoutRepository.getLayoutFile(item.bookId).delete()
+                pdfTextBoxRepository.getFileForSync(item.bookId).delete()
+                pdfHighlightRepository.getFileForSync(item.bookId).delete()
+                ImportedFileCache.clearBookCache(context, item.bookId)
+            } catch (e: Exception) {
+                Timber.e(e, "Error during local cleanup for detached folder book ${item.bookId}")
+            }
         }
     }
 
@@ -381,8 +398,40 @@ class RecentFilesRepository(private val context: Context) {
         }
     }
 
-    suspend fun getFolderBooksWithoutCovers(): List<RecentFileItem> = withContext(Dispatchers.IO) {
-        return@withContext recentFileDao.getFolderBooksWithoutCovers().map { it.toRecentFileItem() }
+    suspend fun getFolderBooksNeedingTextMetadata(sourceFolderUri: String? = null): List<RecentFileItem> = withContext(Dispatchers.IO) {
+        val entities = if (sourceFolderUri.isNullOrBlank()) {
+            recentFileDao.getFolderBooksNeedingTextMetadata()
+        } else {
+            recentFileDao.getFolderBooksNeedingTextMetadata(sourceFolderUri)
+        }
+        return@withContext entities.map { it.toRecentFileItem() }
+    }
+
+    suspend fun hasFolderBooksNeedingTextMetadata(sourceFolderUri: String? = null): Boolean = withContext(Dispatchers.IO) {
+        val count = if (sourceFolderUri.isNullOrBlank()) {
+            recentFileDao.countFolderBooksNeedingTextMetadata()
+        } else {
+            recentFileDao.countFolderBooksNeedingTextMetadata(sourceFolderUri)
+        }
+        return@withContext count > 0
+    }
+
+    suspend fun updateExtractedMetadata(items: List<RecentFileItem>) = withContext(Dispatchers.IO) {
+        if (items.isEmpty()) return@withContext
+        items.chunked(300).forEach { chunk ->
+            database.withTransaction {
+                chunk.forEach { item ->
+                    recentFileDao.updateExtractedMetadata(
+                        bookId = item.bookId,
+                        coverImagePath = item.coverImagePath,
+                        title = item.title,
+                        author = item.author,
+                        fileSize = item.fileSize
+                    )
+                }
+            }
+        }
+        Timber.tag(ReaderPerfLog.TAG).d("Metadata extraction batch updated ${items.size} rows.")
     }
 
     suspend fun detachAllFolderBooks() = withContext(Dispatchers.IO) {

app/src/main/java/com/aryan/reader/epub/EpubBook.kt

@@ -23,6 +23,7 @@ import android.graphics.Bitmap
 import com.aryan.reader.epub.EpubParser.EpubPageTarget
 import kotlinx.serialization.Serializable
 import kotlinx.serialization.Transient
+import java.io.File
 
 @Serializable
 data class EpubTocEntry(
@@ -51,3 +52,14 @@ data class EpubBook(
     val seriesIndex: Double? = null,
     val description: String? = null,
 )
+
+fun EpubBook.hasReadableExtractedContent(): Boolean {
+    if (extractionBasePath.isBlank()) return false
+    val extractionDir = File(extractionBasePath)
+    if (!extractionDir.isDirectory) return false
+    if (chapters.isEmpty()) return extractionDir.list()?.isNotEmpty() == true
+
+    return chapters.all { chapter ->
+        File(extractionDir, chapter.htmlFilePath).isFile
+    }
+}

app/src/main/java/com/aryan/reader/epub/ImportedFileCache.kt

@@ -9,8 +9,12 @@ object ImportedFileCache {
     private const val TEMP_PREFIX = "imported_file_tmp_"
     private val invalidSegmentChars = Regex("[^A-Za-z0-9._-]+")
 
+    fun activeBookDirName(bookId: String): String {
+        return "$ACTIVE_PREFIX${bookMarker(bookId)}"
+    }
+
     fun activeBookDir(context: Context, bookId: String): File {
-        return File(context.cacheDir, "$ACTIVE_PREFIX$bookId")
+        return File(context.cacheDir, activeBookDirName(bookId))
     }
 
     fun prepareActiveBookDir(context: Context, bookId: String): File {
@@ -39,6 +43,7 @@ object ImportedFileCache {
 
     fun clearBookCache(context: Context, bookId: String) {
         activeBookDir(context, bookId).takeIf { it.exists() }?.deleteRecursively()
+        legacyActiveBookDir(context, bookId).takeIf { it.exists() }?.deleteRecursively()
         clearTemporaryBookDirs(context, bookId)
     }
 
@@ -69,6 +74,10 @@ object ImportedFileCache {
         return name.startsWith(ACTIVE_PREFIX) && !isTemporaryBookDir(name)
     }
 
+    private fun legacyActiveBookDir(context: Context, bookId: String): File {
+        return File(context.cacheDir, "$ACTIVE_PREFIX$bookId")
+    }
+
     private fun bookMarker(bookId: String): String {
         val normalized = bookId.toCacheSegment().ifBlank { "book" }.take(40)
         val hash = bookId.hashCode().toLong() and 0xffffffffL

app/src/main/java/com/aryan/reader/epub/MobiParser.kt

@@ -109,10 +109,20 @@ class MobiParser(private val context: Context) {
     private external fun parseMobiFile(filePath: String): ParsedMobiData?
 
     companion object {
-        init {
+        private val nativeLoadError: Throwable? = try {
             System.loadLibrary("mobi")
             System.loadLibrary("native-lib")
+            null
+        } catch (t: Throwable) {
+            Timber.e(t, "MOBI native parser is unavailable on this device.")
+            t
         }
+
+        val isNativeParserAvailable: Boolean
+            get() = nativeLoadError == null
+
+        fun nativeParserUnavailableMessage(): String =
+            nativeLoadError?.message ?: "MOBI native parser is unavailable on this device."
     }
 
     suspend fun createMobiBook(
@@ -122,6 +132,11 @@ class MobiParser(private val context: Context) {
         parseContent: Boolean = true,
         extractionDirOverride: File? = null
     ): EpubBook? = withContext(Dispatchers.IO) {
+        if (!isNativeParserAvailable) {
+            Timber.e("Skipping MOBI parsing: ${nativeParserUnavailableMessage()}")
+            return@withContext null
+        }
+
         val tempFile = File.createTempFile("temp_mobi_", ".mobi", context.cacheDir)
         try {
             tempFile.outputStream().use { output ->

app/src/main/java/com/aryan/reader/epub/SingleFileImporter.kt

@@ -35,6 +35,8 @@ import kotlinx.coroutines.withContext
 import kotlinx.serialization.encodeToString
 import kotlinx.serialization.json.Json
 import org.jsoup.Jsoup
+import org.jsoup.nodes.Document
+import org.jsoup.safety.Safelist
 import org.zwobble.mammoth.DocumentConverter
 import timber.log.Timber
 import java.io.File
@@ -52,6 +54,15 @@ class SingleFileImporter(private val context: Context) {
         private const val MAX_DOCX_XML_BYTES = 48L * 1024L * 1024L
     }
 
+    private val htmlSafelist = Safelist.relaxed()
+        .addTags("article", "aside", "details", "div", "figcaption", "figure", "footer", "header", "main", "section", "summary")
+        .addAttributes(":all", "class", "dir", "id", "lang", "title")
+        .addAttributes("a", "name", "target")
+        .addProtocols("a", "href", "http", "https", "mailto", "tel", "#")
+        .addProtocols("img", "src", "http", "https", "data", "file", "content")
+
+    private val htmlOutputSettings = Document.OutputSettings().prettyPrint(false)
+
     suspend fun importSingleFile(
         inputStream: InputStream,
         type: FileType,
@@ -61,8 +72,9 @@ class SingleFileImporter(private val context: Context) {
     ): EpubBook {
 
         val lowerHint = originalBookNameHint.lowercase()
-        val isCsv = lowerHint.endsWith(".csv") || lowerHint.endsWith(".tsv")
-        val isCodeOrData = listOf(".json", ".xml", ".log", ".java", ".kt", ".py", ".js", ".cpp", ".c", ".cs", ".rb", ".go").any { lowerHint.endsWith(it) }
+        val isCsv = lowerHint.endsWith(".csv") || lowerHint.endsWith(".tsv") ||
+            lowerHint.endsWith(".csv.txt") || lowerHint.endsWith(".tsv.txt")
+        val isCodeOrData = com.aryan.reader.isCodeOrDataFileName(originalBookNameHint)
 
         if (type == FileType.HTML && (isCsv || isCodeOrData)) {
             return parseDynamicContentToHtml(inputStream, originalBookNameHint, bookId, parseContent, isCsv)
@@ -99,7 +111,7 @@ class SingleFileImporter(private val context: Context) {
                     writer.write("</head>\n<body>\n<pre><code>\n")
                 }
 
-                val delimiter = if (originalBookNameHint.lowercase().endsWith(".tsv")) '\t' else ','
+                val delimiter = if (originalBookNameHint.lowercase().let { it.endsWith(".tsv") || it.endsWith(".tsv.txt") }) '\t' else ','
 
                 inputStream.bufferedReader().use { reader ->
                     var line = reader.readLine()
@@ -177,11 +189,7 @@ class SingleFileImporter(private val context: Context) {
             )
         }
 
-        File(context.cacheDir, "imported_file_$bookId").deleteRecursively()
-
-        val extractionDir = File(context.cacheDir, "imported_file_$bookId").apply {
-            if (!exists()) mkdirs()
-        }
+        val extractionDir = ImportedFileCache.prepareActiveBookDir(context, bookId)
         val metadataFile = File(extractionDir, "book_metadata.json")
 
         if (metadataFile.exists()) {
@@ -245,7 +253,7 @@ class SingleFileImporter(private val context: Context) {
                 val chapterTitle = "Page $pageNum"
 
                 val document = parser.parse(rawText)
-                val htmlBody = renderer.render(document)
+                val htmlBody = sanitizeHtmlFragment(renderer.render(document))
 
                 val fileName = "page_$pageNum.html"
                 val file = File(extractionDir, fileName)
@@ -315,11 +323,7 @@ class SingleFileImporter(private val context: Context) {
             )
         }
 
-        File(context.cacheDir, "imported_file_$bookId").deleteRecursively()
-
-        val extractionDir = File(context.cacheDir, "imported_file_$bookId").apply {
-            if (!exists()) mkdirs()
-        }
+        val extractionDir = ImportedFileCache.prepareActiveBookDir(context, bookId)
         val metadataFile = File(extractionDir, "book_metadata.json")
 
         if (metadataFile.exists()) {
@@ -480,11 +484,7 @@ class SingleFileImporter(private val context: Context) {
             )
         }
 
-        File(context.cacheDir, "imported_file_$bookId").deleteRecursively()
-
-        val extractionDir = File(context.cacheDir, "imported_file_$bookId").apply {
-            if (!exists()) mkdirs()
-        }
+        val extractionDir = ImportedFileCache.prepareActiveBookDir(context, bookId)
         val metadataFile = File(extractionDir, "book_metadata.json")
 
         if (metadataFile.exists()) {
@@ -507,6 +507,7 @@ class SingleFileImporter(private val context: Context) {
         val chapters = mutableListOf<EpubChapter>()
 
         inputStream.bufferedReader().use { reader ->
+            var inScript = false
             var inStyle = false
             var inBody = false
             var pageNum = 1
@@ -516,6 +517,19 @@ class SingleFileImporter(private val context: Context) {
             while (reader.readLine().also { line = it } != null) {
                 val trimmed = line!!.trim()
 
+                if (inScript) {
+                    if (trimmed.contains("</script", ignoreCase = true)) {
+                        inScript = false
+                    }
+                    continue
+                }
+                if (trimmed.startsWith("<script", ignoreCase = true)) {
+                    if (!trimmed.contains("</script", ignoreCase = true)) {
+                        inScript = true
+                    }
+                    continue
+                }
+
                 if (!inBody) {
                     if (trimmed.startsWith("<title", ignoreCase = true)) {
                         val t = trimmed.substringAfter(">").substringBefore("</title>")
@@ -632,6 +646,10 @@ class SingleFileImporter(private val context: Context) {
         return@withContext book
     }
 
+    private fun sanitizeHtmlFragment(html: String): String {
+        return Jsoup.clean(html, "", htmlSafelist, htmlOutputSettings)
+    }
+
     private suspend fun parseDocx(
         inputStream: InputStream,
         originalBookNameHint: String,
@@ -654,11 +672,7 @@ class SingleFileImporter(private val context: Context) {
             )
         }
 
-        File(context.cacheDir, "imported_file_$bookId").deleteRecursively()
-
-        val extractionDir = File(context.cacheDir, "imported_file_$bookId").apply {
-            if (!exists()) mkdirs()
-        }
+        val extractionDir = ImportedFileCache.prepareActiveBookDir(context, bookId)
         val metadataFile = File(extractionDir, "book_metadata.json")
 
         if (metadataFile.exists()) {
@@ -754,8 +768,9 @@ class SingleFileImporter(private val context: Context) {
         val chapterTitle = if (pageNum > 1 || bodyContent.contains("<page-break")) "Page $pageNum" else title
         val fileName = "page_$pageNum.html"
         val file = File(extractionDir, fileName)
+        val sanitizedBodyContent = sanitizeHtmlFragment(bodyContent)
 
-        val fullHtml = "<!DOCTYPE html>\n<html xmlns=\"http://www.w3.org/1999/xhtml\">\n<head>\n<title>${title.replace("\"", "&quot;")}</title>\n<style>${cssStyle}</style>\n</head>\n<body>\n${bodyContent.trim()}\n</body>\n</html>"
+        val fullHtml = "<!DOCTYPE html>\n<html xmlns=\"http://www.w3.org/1999/xhtml\">\n<head>\n<title>${title.replace("\"", "&quot;")}</title>\n<style>${cssStyle}</style>\n</head>\n<body>\n${sanitizedBodyContent.trim()}\n</body>\n</html>"
 
         file.writeText(fullHtml)
 

app/src/main/java/com/aryan/reader/epubreader/ChapterWebView.kt

@@ -26,10 +26,8 @@ import android.content.ClipData
 import android.content.ClipboardManager
 import android.content.Context
 import android.content.Intent
-import android.graphics.BitmapFactory
 import android.graphics.Color
 import android.graphics.Rect
-import android.util.Base64
 import android.webkit.JavascriptInterface
 import android.webkit.WebResourceRequest
 import android.webkit.WebSettings
@@ -83,13 +81,12 @@ import androidx.compose.ui.window.Popup
 import androidx.compose.ui.window.PopupPositionProvider
 import androidx.core.net.toUri
 import com.aryan.reader.R
-import com.aryan.reader.ReaderTexture
+import com.aryan.reader.getReaderTextureDataUri
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.launch
 import org.json.JSONObject
 import timber.log.Timber
 import java.io.BufferedReader
-import java.io.ByteArrayOutputStream
 import java.io.InputStreamReader
 
 private const val TAG_LINK_NAV = "LINK_NAV"
@@ -351,6 +348,7 @@ fun ChapterWebView(
     currentParagraphGap: Float,
     currentImageSize: Float,
     currentHorizontalMargin: Float,
+    currentVerticalMargin: Float,
     onChapterInitiallyScrolled: () -> Unit,
     modifier: Modifier = Modifier,
     onTap: () -> Unit,
@@ -386,7 +384,8 @@ fun ChapterWebView(
     activeHighlightPalette: List<HighlightColor>,
     onUpdatePalette: (Int, HighlightColor) -> Unit,
     onInternalLinkClick: (String) -> Unit,
-    activeTextureId: String? = null
+    activeTextureId: String? = null,
+    activeTextureAlpha: Float = 0.55f
 ) {
     Timber.d(
         "RenderChapterViaWebView for '$chapterTitle', Key: $key, isDarkTheme: $isDarkTheme, initialScrollTarget: $initialScrollTarget"
@@ -406,17 +405,8 @@ fun ChapterWebView(
 
     val textureBase64 by remember(activeTextureId) {
         mutableStateOf(
-            activeTextureId?.let { id ->
-                ReaderTexture.entries.find { it.id == id }?.resId?.let { resId ->
-                    val bmp = BitmapFactory.decodeResource(context.resources, resId)
-                    val out = ByteArrayOutputStream()
-                    bmp.compress(android.graphics.Bitmap.CompressFormat.PNG, 100, out)
-                    "data:image/png;base64," + Base64.encodeToString(
-                        out.toByteArray(),
-                        Base64.NO_WRAP
-                    )
-                }
-            })
+            getReaderTextureDataUri(context, activeTextureId)
+        )
     }
 
     val currentOnSnippetForBookmarkReady by rememberUpdatedState(onSnippetForBookmarkReady)
@@ -476,10 +466,10 @@ fun ChapterWebView(
 
     Box(modifier = modifier.fillMaxSize()) {
 
-        LaunchedEffect(isDarkTheme, effectiveBg, effectiveText, textureBase64) {
+        LaunchedEffect(isDarkTheme, effectiveBg, effectiveText, textureBase64, activeTextureAlpha) {
             val bgHex = String.format("#%06X", (0xFFFFFF and effectiveBg.toArgb()))
             val textHex = String.format("#%06X", (0xFFFFFF and effectiveText.toArgb()))
-            localWebViewRef?.evaluateJavascript("javascript:window.applyReaderTheme($isDarkTheme, '$bgHex', '$textHex', ${textureBase64?.let { "'$it'" } ?: "null"});", null)
+            localWebViewRef?.evaluateJavascript("javascript:window.applyReaderTheme($isDarkTheme, '$bgHex', '$textHex', ${textureBase64?.let { "'$it'" } ?: "null"}, ${activeTextureAlpha.coerceIn(0f, 1f)});", null)
         }
 
         key(
@@ -489,6 +479,7 @@ fun ChapterWebView(
             currentParagraphGap,
             currentImageSize,
             currentHorizontalMargin,
+            currentVerticalMargin,
             currentFontFamily,
             currentTextAlign
         ) {
@@ -737,7 +728,7 @@ fun ChapterWebView(
                             val bgHex = String.format("#%06X", (0xFFFFFF and effectiveBg.toArgb()))
                             val textHex =
                                 String.format("#%06X", (0xFFFFFF and effectiveText.toArgb()))
-                            view?.evaluateJavascript("javascript:window.applyReaderTheme($isDarkTheme, '$bgHex', '$textHex', ${textureBase64?.let { "'$it'" } ?: "null"});",
+                            view?.evaluateJavascript("javascript:window.applyReaderTheme($isDarkTheme, '$bgHex', '$textHex', ${textureBase64?.let { "'$it'" } ?: "null"}, ${activeTextureAlpha.coerceIn(0f, 1f)});",
                                 null)
 
                             val fragmentsJson = org.json.JSONArray(tocFragments).toString()
@@ -782,7 +773,7 @@ fun ChapterWebView(
                             }
 
                             view?.evaluateJavascript(
-                                "javascript:window.updateReaderStyles($currentFontSize, $currentLineHeight, '$fontNameForJs', '${currentTextAlign.cssValue}', $currentParagraphGap, $currentImageSize, $currentHorizontalMargin);",
+                                "javascript:window.updateReaderStyles($currentFontSize, $currentLineHeight, '$fontNameForJs', '${currentTextAlign.cssValue}', $currentParagraphGap, $currentImageSize, $currentHorizontalMargin, $currentVerticalMargin);",
                                 null
                             )
 
@@ -946,7 +937,7 @@ fun ChapterWebView(
                 )
 
                 webView.evaluateJavascript(
-                    "javascript:window.updateReaderStyles($currentFontSize, $currentLineHeight, '$fontNameForJs', '${currentTextAlign.cssValue}', $currentParagraphGap, $currentImageSize, $currentHorizontalMargin);",
+                    "javascript:window.updateReaderStyles($currentFontSize, $currentLineHeight, '$fontNameForJs', '${currentTextAlign.cssValue}', $currentParagraphGap, $currentImageSize, $currentHorizontalMargin, $currentVerticalMargin);",
                     null
                 )
 

app/src/main/java/com/aryan/reader/epubreader/DictionarySettingsDialog.kt

@@ -41,8 +41,8 @@ import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.window.Dialog
 import androidx.core.graphics.drawable.toBitmap
-import com.aryan.reader.BuildConfig
 import com.aryan.reader.R
+import com.aryan.reader.areReaderAiFeaturesEnabled
 
 @Suppress("KotlinConstantConditions")
 @OptIn(ExperimentalMaterial3Api::class)
@@ -92,7 +92,7 @@ fun DictionarySettingsDialog(
                 )
 
                 // ── Dictionary ──
-                if (BuildConfig.FLAVOR != "oss") {
+                if (areReaderAiFeaturesEnabled(context)) {
                     Surface(
                         shape = RoundedCornerShape(16.dp),
                         color = MaterialTheme.colorScheme.surfaceContainerHigh,

app/src/main/java/com/aryan/reader/epubreader/EpubReaderAi.kt

@@ -32,11 +32,14 @@ import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.style.TextAlign
 import com.aryan.reader.AiDefinitionPopup
+import com.aryan.reader.AiFeature
 import com.aryan.reader.AiDefinitionResult
 import com.aryan.reader.AiHubBottomSheet
+import com.aryan.reader.BuildConfig
 import com.aryan.reader.R
 import com.aryan.reader.SummarizationResult
 import com.aryan.reader.SummaryCacheManager
+import com.aryan.reader.callByokTextAi
 import com.aryan.reader.epub.EpubBook
 import com.aryan.reader.fetchRecap
 import com.aryan.reader.paginatedreader.IPaginator
@@ -55,6 +58,7 @@ import java.net.URL
  */
 suspend fun summarizeBookContent(
     content: String,
+    context: Context,
     authToken: String?,
     onUsageReceived: (cost: Double?, freeRemaining: Int?) -> Unit = { _, _ -> },
     onUpdate: (String) -> Unit,
@@ -68,6 +72,27 @@ suspend fun summarizeBookContent(
     }
     Timber.d("Starting summarization for content of length: ${content.length}")
 
+    @Suppress("KotlinConstantConditions")
+    if (BuildConfig.FLAVOR == "oss") {
+        if (BuildConfig.IS_OFFLINE) {
+            onError("AI features are unavailable in the offline OSS build.")
+            onFinish()
+            return
+        }
+        callByokTextAi(
+            context = context,
+            feature = AiFeature.SUMMARIZE,
+            systemInstruction = "You are an expert in analyzing written content. Provide a concise, easy-to-read summary of the provided chapter. Identify the main ideas, plot points, and themes. Do not add a preamble like 'Here is the summary:'",
+            userPrompt = content,
+            temperature = 0.2,
+            maxTokens = 8192,
+            onUpdate = onUpdate,
+            onError = onError
+        )
+        onFinish()
+        return
+    }
+
     withContext(Dispatchers.IO) {
         var connection: HttpURLConnection? = null
         try {
@@ -196,6 +221,7 @@ suspend fun executeRecapLogic(
 
                 summarizeBookContent(
                     content = textToSummarize,
+                    context = context,
                     authToken = authToken,
                     onUsageReceived = { cost, _ ->
                         Timber.i("[AI-Billing] Background past chapter summary cost: $cost credits")

app/src/main/java/com/aryan/reader/epubreader/EpubReaderDrawer.kt

@@ -123,7 +123,9 @@ fun VerticalScrollbar(
 
             if (viewportRatio >= 1f) return@derivedStateOf null
 
-            val thumbHeight = (viewportHeight * viewportRatio).coerceIn(80f, viewportHeight / 2)
+            val maxThumbHeight = viewportHeight / 2f
+            val minThumbHeight = minOf(80f, maxThumbHeight)
+            val thumbHeight = (viewportHeight * viewportRatio).coerceIn(minThumbHeight, maxThumbHeight)
 
             val firstItemIndex = listState.firstVisibleItemIndex
             val firstItemOffset = listState.firstVisibleItemScrollOffset

app/src/main/java/com/aryan/reader/epubreader/EpubReaderScreen.kt

@@ -19,7 +19,7 @@
  */
 // EpubReaderScreen.kt
 @file:OptIn(ExperimentalSerializationApi::class) @file:Suppress("VariableNeverRead",
-    "UnusedVariable", "Unused", "SimplifyBooleanWithConstants"
+    "UnusedVariable", "Unused", "SimplifyBooleanWithConstants", "KotlinConstantConditions"
 )
 
 package com.aryan.reader.epubreader
@@ -35,6 +35,8 @@ import android.graphics.Bitmap
 import android.media.AudioManager
 import android.net.Uri
 import android.os.Build
+import android.view.RoundedCorner
+import android.view.View
 import android.webkit.WebView
 import android.widget.Toast
 import androidx.activity.compose.BackHandler
@@ -119,9 +121,14 @@ import androidx.compose.ui.Alignment
 import androidx.compose.ui.BiasAlignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.alpha
+import androidx.compose.ui.draw.drawBehind
 import androidx.compose.ui.focus.FocusRequester
 import androidx.compose.ui.focus.focusRequester
+import androidx.compose.ui.graphics.BlendMode
 import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.ImageShader
+import androidx.compose.ui.graphics.ShaderBrush
+import androidx.compose.ui.graphics.TileMode
 import androidx.compose.ui.input.pointer.pointerInput
 import androidx.compose.ui.platform.LocalConfiguration
 import androidx.compose.ui.platform.LocalContext
@@ -134,6 +141,7 @@ import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.style.TextAlign
 import androidx.compose.ui.text.style.TextOverflow
+import androidx.compose.ui.unit.Dp
 import androidx.compose.ui.unit.dp
 import androidx.core.content.ContextCompat
 import androidx.core.content.edit
@@ -158,12 +166,17 @@ import com.aryan.reader.SearchResult
 import com.aryan.reader.SummarizationResult
 import com.aryan.reader.SummaryCacheManager
 import com.aryan.reader.TtsSettingsSheet
+import com.aryan.reader.areReaderAiFeaturesEnabled
 import com.aryan.reader.countWords
+import com.aryan.reader.isByokCloudTtsAvailable
 import com.aryan.reader.data.CustomFontEntity
 import com.aryan.reader.epub.EpubBook
+import com.aryan.reader.epub.hasReadableExtractedContent
 import com.aryan.reader.fetchAiDefinition
 import com.aryan.reader.loadCustomThemes
+import com.aryan.reader.loadGlobalTextureTransparency
 import com.aryan.reader.loadReaderThemeId
+import com.aryan.reader.loadReaderTextureBitmap
 import com.aryan.reader.paginatedreader.BookPaginator
 import com.aryan.reader.paginatedreader.CfiUtils
 import com.aryan.reader.paginatedreader.HeaderBlock
@@ -180,11 +193,11 @@ import com.aryan.reader.paginatedreader.data.BookCacheDatabase
 import com.aryan.reader.paginatedreader.semanticBlockModule
 import com.aryan.reader.rememberSearchState
 import com.aryan.reader.saveCustomThemes
+import com.aryan.reader.saveGlobalTextureTransparency
 import com.aryan.reader.saveReaderThemeId
 import com.aryan.reader.tts.SpeakerSamplePlayer
 import com.aryan.reader.tts.TtsPlaybackManager
 import com.aryan.reader.tts.loadTtsMode
-import com.aryan.reader.tts.rememberTtsController
 import com.aryan.reader.tts.splitTextIntoChunks
 import kotlinx.coroutines.Job
 import kotlinx.coroutines.delay
@@ -218,12 +231,50 @@ private const val AUTO_SCROLL_LOCAL_MAX_PREFIX = "auto_scroll_local_max_"
 private const val MUSICIAN_MODE_KEY = "musician_mode_enabled"
 private const val KEEP_SCREEN_ON_KEY = "keep_screen_on_enabled"
 private const val HIDDEN_TOOLS_KEY = "hidden_reader_tools"
+private const val TOOL_ORDER_KEY = "reader_tool_order"
+private const val BOTTOM_TOOLS_KEY = "reader_bottom_tools"
 private const val TTS_LOCATE_REASON_INITIAL_RESTORE = "initial_restore"
 private const val TTS_LOCATE_REASON_LIFECYCLE_RESUME = "lifecycle_resume"
 private const val TTS_LOCATE_REASON_OVERLAY = "overlay"
 
 private const val TAG_LINK_NAV = "LINK_NAV"
 
+private fun View.bottomRoundedCornerRadiusPx(): Int {
+    if (Build.VERSION.SDK_INT < Build.VERSION_CODES.S) return 0
+
+    val insets = rootWindowInsets ?: return 0
+    return max(
+        insets.getRoundedCorner(RoundedCorner.POSITION_BOTTOM_LEFT)?.radius ?: 0,
+        insets.getRoundedCorner(RoundedCorner.POSITION_BOTTOM_RIGHT)?.radius ?: 0
+    )
+}
+
+@Composable
+private fun rememberBottomRoundedCornerPadding(view: View): Dp {
+    val density = LocalDensity.current
+    val configuration = LocalConfiguration.current
+    var radiusPx by remember(view) { mutableIntStateOf(view.bottomRoundedCornerRadiusPx()) }
+
+    DisposableEffect(
+        view,
+        configuration.orientation,
+        configuration.screenWidthDp,
+        configuration.screenHeightDp
+    ) {
+        val listener = View.OnLayoutChangeListener { updatedView, _, _, _, _, _, _, _, _ ->
+            radiusPx = updatedView.bottomRoundedCornerRadiusPx()
+        }
+        view.addOnLayoutChangeListener(listener)
+        radiusPx = view.bottomRoundedCornerRadiusPx()
+
+        onDispose {
+            view.removeOnLayoutChangeListener(listener)
+        }
+    }
+
+    return with(density) { radiusPx.toDp() }
+}
+
 private fun saveHiddenTools(context: Context, hiddenTools: Set<String>) {
     val prefs = context.getSharedPreferences("reader_prefs", Context.MODE_PRIVATE)
     prefs.edit { putStringSet(HIDDEN_TOOLS_KEY, hiddenTools) }
@@ -234,6 +285,34 @@ private fun loadHiddenTools(context: Context): Set<String> {
     return prefs.getStringSet(HIDDEN_TOOLS_KEY, emptySet()) ?: emptySet()
 }
 
+private fun saveToolOrder(context: Context, toolOrder: List<ReaderTool>) {
+    val prefs = context.getSharedPreferences("reader_prefs", Context.MODE_PRIVATE)
+    prefs.edit { putString(TOOL_ORDER_KEY, toolOrder.joinToString(",") { it.name }) }
+}
+
+private fun loadToolOrder(context: Context): List<ReaderTool> {
+    val prefs = context.getSharedPreferences("reader_prefs", Context.MODE_PRIVATE)
+    val savedTools = prefs.getString(TOOL_ORDER_KEY, null)
+        ?.split(',')
+        ?.filter { it.isNotBlank() }
+        ?.mapNotNull { name -> ReaderTool.entries.firstOrNull { it.name == name } }
+        .orEmpty()
+    return (savedTools + ReaderTool.entries.filterNot { it in savedTools }).distinct()
+}
+
+private fun saveBottomTools(context: Context, bottomTools: Set<String>) {
+    val prefs = context.getSharedPreferences("reader_prefs", Context.MODE_PRIVATE)
+    prefs.edit { putStringSet(BOTTOM_TOOLS_KEY, bottomTools) }
+}
+
+private fun loadBottomTools(context: Context): Set<String> {
+    val prefs = context.getSharedPreferences("reader_prefs", Context.MODE_PRIVATE)
+    return prefs.getStringSet(
+        BOTTOM_TOOLS_KEY,
+        ReaderTool.entries.filter { it.category == "Bottom Bar" }.map { it.name }.toSet()
+    ) ?: ReaderTool.entries.filter { it.category == "Bottom Bar" }.map { it.name }.toSet()
+}
+
 private fun saveKeepScreenOn(context: Context, isEnabled: Boolean) {
     val prefs = context.getSharedPreferences("reader_prefs", Context.MODE_PRIVATE)
     prefs.edit { putBoolean(KEEP_SCREEN_ON_KEY, isEnabled) }
@@ -338,7 +417,7 @@ private const val PREF_EXTERNAL_TRANSLATE_PKG = "external_translate_package"
 private const val PREF_EXTERNAL_SEARCH_PKG = "external_search_package"
 
 private fun loadUseOnlineDict(context: Context): Boolean {
-    @Suppress("KotlinConstantConditions") if (BuildConfig.FLAVOR == "oss") return false
+    @Suppress("KotlinConstantConditions") if (BuildConfig.FLAVOR == "oss" && BuildConfig.IS_OFFLINE) return false
     val prefs = context.getSharedPreferences("reader_prefs", Context.MODE_PRIVATE)
     return prefs.getBoolean(PREF_USE_ONLINE_DICT, true)
 }
@@ -381,6 +460,7 @@ private fun saveExternalSearchPackage(context: Context, packageName: String) {
 const val PREF_READER_THEME = "reader_theme_id"
 const val PREF_CUSTOM_THEMES = "custom_themes_json"
 
+@UnstableApi
 @RequiresApi(Build.VERSION_CODES.VANILLA_ICE_CREAM)
 @Composable
 fun EpubReaderScreen(
@@ -416,8 +496,8 @@ fun EpubReaderScreen(
         }
     } else null
 
-    val hasValidExtractionBasePath = remember(epubBook.extractionBasePath) {
-        epubBook.extractionBasePath.isNotBlank() && File(epubBook.extractionBasePath).exists()
+    val hasValidExtractionBasePath = remember(epubBook.extractionBasePath, epubBook.chapters) {
+        epubBook.hasReadableExtractedContent()
     }
     var requestedContentRecovery by remember(epubBook.extractionBasePath, uiState.selectedBookId) {
         mutableStateOf(false)
@@ -563,6 +643,7 @@ fun EpubReaderHost(
 
     var systemUiMode by remember { mutableStateOf(loadSystemUiMode(context)) }
     var pageInfoMode by remember { mutableStateOf(loadPageInfoMode(context)) }
+    var pageInfoPosition by remember { mutableStateOf(loadPageInfoPosition(context)) }
     var pullToTurnEnabled by remember { mutableStateOf(loadPullToTurn(context)) }
     var pullToTurnMultiplier by remember { mutableFloatStateOf(loadPullToTurnMultiplier(context)) }
     var showVisualOptionsSheet by remember { mutableStateOf(false) }
@@ -582,7 +663,7 @@ fun EpubReaderHost(
     var currentTtsMode by remember {
         mutableStateOf(
             loadTtsMode(context).let {
-                if (BuildConfig.FLAVOR == "oss") TtsPlaybackManager.TtsMode.BASE else it
+                if (BuildConfig.FLAVOR == "oss" && !isByokCloudTtsAvailable(context)) TtsPlaybackManager.TtsMode.BASE else it
             }
         )
     }
@@ -738,18 +819,19 @@ fun EpubReaderHost(
     }
 
     var hiddenTools by remember { mutableStateOf(loadHiddenTools(context)) }
+    var toolOrder by remember { mutableStateOf(loadToolOrder(context)) }
+    var bottomTools by remember { mutableStateOf(loadBottomTools(context)) }
     var showCustomizeToolsSheet by remember { mutableStateOf(false) }
 
     var showDictionaryUpsellDialog by remember { mutableStateOf(false) }
     var showSummarizationUpsellDialog by remember { mutableStateOf(false) }
 
     @Suppress("KotlinConstantConditions") val onDictionaryLookup = { word: String ->
-        val isOss = BuildConfig.FLAVOR == "oss"
-        val effectiveUseOnline = !isOss && useOnlineDictionary
+        val effectiveUseOnline = areReaderAiFeaturesEnabled(context) && useOnlineDictionary
 
         if (effectiveUseOnline) {
             val wordCount = countWords(word)
-            if (wordCount > 1 && !isProUser) {
+            if (BuildConfig.FLAVOR != "oss" && wordCount > 1 && !isProUser) {
                 showDictionaryUpsellDialog = true
             } else {
                 selectedTextForAi = word
@@ -815,6 +897,8 @@ fun EpubReaderHost(
     var lastKnownLocator by remember(initialLocator) { mutableStateOf(initialLocator) }
 
     val bottomPadding = WindowInsets.navigationBars.asPaddingValues().calculateBottomPadding()
+    val roundedCornerBottomPadding = rememberBottomRoundedCornerPadding(view)
+    val pageInfoCornerBottomPadding = roundedCornerBottomPadding.coerceAtMost(8.dp)
 
     var bookmarks by remember(epubBook.title) {
         mutableStateOf(
@@ -991,6 +1075,7 @@ fun EpubReaderHost(
     var currentParagraphGap by remember(initialFormatSettings) { mutableFloatStateOf(initialFormatSettings.paragraphGap) }
     var currentImageSize by remember(initialFormatSettings) { mutableFloatStateOf(initialFormatSettings.imageSize) }
     var currentHorizontalMargin by remember(initialFormatSettings) { mutableFloatStateOf(initialFormatSettings.horizontalMargin) }
+    var currentVerticalMargin by remember(initialFormatSettings) { mutableFloatStateOf(initialFormatSettings.verticalMargin) }
     var currentTextAlign by remember(initialFormatSettings) { mutableStateOf(initialFormatSettings.textAlign) }
     var currentFontFamily by remember(initialFormatSettings) { mutableStateOf(initialFormatSettings.font) }
     var currentCustomFontPath by remember(initialFormatSettings) { mutableStateOf(initialFormatSettings.customPath) }
@@ -1006,14 +1091,14 @@ fun EpubReaderHost(
     var showFontSelectionSheet by remember { mutableStateOf(false) }
     val fontSheetState = rememberModalBottomSheetState()
 
-    LaunchedEffect(currentFontSizeEm, currentLineHeight, currentParagraphGap, currentImageSize, currentHorizontalMargin, currentFontFamily, currentCustomFontPath, currentTextAlign, isFormatLocal) {
+    LaunchedEffect(currentFontSizeEm, currentLineHeight, currentParagraphGap, currentImageSize, currentHorizontalMargin, currentVerticalMargin, currentFontFamily, currentCustomFontPath, currentTextAlign, isFormatLocal) {
         if (isFormatLocal) {
             saveLocalReaderSettings(
-                context, bookId, currentFontSizeEm, currentLineHeight, currentParagraphGap, currentImageSize, currentHorizontalMargin, currentFontFamily, currentCustomFontPath, currentTextAlign
+                context, bookId, currentFontSizeEm, currentLineHeight, currentParagraphGap, currentImageSize, currentHorizontalMargin, currentVerticalMargin, currentFontFamily, currentCustomFontPath, currentTextAlign
             )
         } else {
             saveReaderSettings(
-                context, currentFontSizeEm, currentLineHeight, currentParagraphGap, currentImageSize, currentHorizontalMargin, currentFontFamily, currentCustomFontPath, currentTextAlign
+                context, currentFontSizeEm, currentLineHeight, currentParagraphGap, currentImageSize, currentHorizontalMargin, currentVerticalMargin, currentFontFamily, currentCustomFontPath, currentTextAlign
             )
         }
     }
@@ -1130,6 +1215,7 @@ fun EpubReaderHost(
 
     var currentThemeId by remember { mutableStateOf(loadReaderThemeId(context)) }
     var customThemes by remember { mutableStateOf(loadCustomThemes(context)) }
+    var globalTextureTransparency by remember { mutableFloatStateOf(loadGlobalTextureTransparency(context)) }
 
     val activeTheme = remember(currentThemeId, customThemes) {
         BuiltInThemes.find { it.id == currentThemeId }
@@ -1151,6 +1237,19 @@ fun EpubReaderHost(
         } else activeTheme.textColor
     }
     val activeTextureId = activeTheme.textureId
+    val activeTextureAlpha = 1f - globalTextureTransparency
+    val activeTextureBitmap = remember(activeTextureId) {
+        loadReaderTextureBitmap(context, activeTextureId)
+    }
+    val activeTextureModifier = activeTextureBitmap?.let { bitmap ->
+        Modifier.drawBehind {
+            drawRect(
+                brush = ShaderBrush(ImageShader(bitmap, TileMode.Repeated, TileMode.Repeated)),
+                blendMode = BlendMode.SrcOver,
+                alpha = activeTextureAlpha.coerceIn(0f, 1f)
+            )
+        }
+    } ?: Modifier
 
     val infoBarBgColor = remember(effectiveBg, isDarkTheme) {
         val overlayAlpha = if (isDarkTheme) 0.08f else 0.06f
@@ -1401,7 +1500,7 @@ fun EpubReaderHost(
     }
 
     fun startTts() {
-        if (currentTtsMode == TtsPlaybackManager.TtsMode.CLOUD && credits <= 0) {
+        if (BuildConfig.FLAVOR != "oss" && currentTtsMode == TtsPlaybackManager.TtsMode.CLOUD && credits <= 0) {
             showInsufficientCreditsDialog = true
             return
         }
@@ -1441,6 +1540,7 @@ fun EpubReaderHost(
                                 chapterTitle = chapterTitle,
                                 coverImageUri = coverUriString,
                                 chapterIndex = chapterIndex,
+                                totalChapters = chapters.size,
                                 ttsMode = currentTtsMode,
                                 playbackSource = "READER",
                                 authToken = token
@@ -1460,7 +1560,7 @@ fun EpubReaderHost(
     )
 
     fun startTtsFromSelectionPaginated(baseCfi: String, startOffset: Int) {
-        if (currentTtsMode == TtsPlaybackManager.TtsMode.CLOUD && credits <= 0) {
+        if (BuildConfig.FLAVOR != "oss" && currentTtsMode == TtsPlaybackManager.TtsMode.CLOUD && credits <= 0) {
             showInsufficientCreditsDialog = true
             return
         }
@@ -1504,6 +1604,7 @@ fun EpubReaderHost(
                             chapterTitle = chapterTitle,
                             coverImageUri = coverUriString,
                             chapterIndex = chapterIndex,
+                            totalChapters = chapters.size,
                             ttsMode = currentTtsMode,
                             playbackSource = "READER",
                             authToken = token
@@ -1582,18 +1683,6 @@ fun EpubReaderHost(
         focusRequester = searchFocusRequester
     )
 
-    if (epubBook.extractionBasePath.isBlank() || !File(epubBook.extractionBasePath).exists()) {
-        Timber.e("Extraction base path is blank or does not exist: ${epubBook.extractionBasePath}"
-        )
-        Box(modifier = Modifier.fillMaxSize(), contentAlignment = Alignment.Center) {
-            Text(
-                "Error: Book content not found. Path: ${epubBook.extractionBasePath}",
-                color = MaterialTheme.colorScheme.error
-            )
-        }
-        return
-    }
-
     val totalPagesInCurrentChapter = remember(currentScrollHeightValue, currentClientHeightValue) {
         if (currentClientHeightValue > 0) {
             max(
@@ -1989,10 +2078,7 @@ fun EpubReaderHost(
         }
     }
 
-    val pageInfoBottomPadding by animateDpAsState(
-        targetValue = if (showBars && pageInfoMode == PageInfoMode.SYNC) 45.dp else 0.dp,
-        label = "PageInfoBottomPadding"
-    )
+    val pageInfoBarHeight = PAGE_INFO_BAR_HEIGHT + pageInfoCornerBottomPadding
 
     val isPageInfoVisible = when (pageInfoMode) {
         PageInfoMode.DEFAULT -> !showBars
@@ -2631,7 +2717,7 @@ fun EpubReaderHost(
         }
 
         val handleGenerateSummary: (Boolean) -> Unit = { force ->
-            if (!isProUser && credits <= 0) {
+            if (BuildConfig.FLAVOR != "oss" && !isProUser && credits <= 0) {
                 showInsufficientCreditsDialog = true
                 showAiHubSheet = false
             } else {
@@ -2688,6 +2774,7 @@ fun EpubReaderHost(
                                     val finalSummaryBuilder = StringBuilder()
                                     summarizeBookContent(
                                         content = text,
+                                        context = context,
                                         authToken = token,
                                         onUsageReceived = { cost, freeRemaining ->
                                             currentCost = cost
@@ -2750,7 +2837,7 @@ fun EpubReaderHost(
         }
 
         val handleGenerateRecap: () -> Unit = {
-            if (credits <= 0) {
+            if (BuildConfig.FLAVOR != "oss" && credits <= 0) {
                 showInsufficientCreditsDialog = true
                 showAiHubSheet = false
             } else {
@@ -2820,6 +2907,7 @@ fun EpubReaderHost(
                 modifier = Modifier
                     .fillMaxSize()
                     .background(effectiveBg)
+                    .then(activeTextureModifier)
                     .padding(top = effectiveTopPadding)
                     .focusRequester(containerFocusRequester)
                     .focusable()
@@ -2879,13 +2967,15 @@ fun EpubReaderHost(
             ) {
                 when (currentRenderMode) {
                     RenderMode.VERTICAL_SCROLL -> {
-                        val contentBottomPadding = if (pageInfoMode != PageInfoMode.HIDDEN) PAGE_INFO_BAR_HEIGHT else 0.dp
+                        val pageInfoReserve = if (pageInfoMode != PageInfoMode.HIDDEN) pageInfoBarHeight else 0.dp
+                        val contentTopPadding = if (pageInfoPosition == PageInfoPosition.TOP) pageInfoReserve else 0.dp
+                        val contentBottomPadding = if (pageInfoPosition == PageInfoPosition.BOTTOM) pageInfoReserve else 0.dp
 
                         Box(
                             modifier = Modifier
                                 .fillMaxSize()
+                                .padding(top = contentTopPadding)
                                 .padding(bottom = contentBottomPadding)
-                                .padding(top = 16.dp)
                                 .testTag("ReaderContainer")
                         ) {
                             if (chapters.isEmpty()) {
@@ -3292,10 +3382,12 @@ fun EpubReaderHost(
                                             currentParagraphGap = currentParagraphGap,
                                             currentImageSize = currentImageSize,
                                             currentHorizontalMargin = currentHorizontalMargin,
+                                            currentVerticalMargin = currentVerticalMargin,
                                             currentFontFamily = currentFontFamily,
                                             customFontPath = currentCustomFontPath,
                                             currentTextAlign = currentTextAlign,
                                             activeTextureId = activeTextureId,
+                                            activeTextureAlpha = activeTextureAlpha,
                                             onHighlightClicked = {
                                                 lastHighlightClickTime = System.currentTimeMillis()
                                                 showBars = false
@@ -3462,7 +3554,7 @@ fun EpubReaderHost(
 
                                                     if (ttsChunks.isNotEmpty()) {
                                                         logTtsChapterDiag("Vertical TTS extraction produced ${ttsChunks.size} chunks for chapter $targetChapterIndex")
-                                                        if (currentTtsMode == TtsPlaybackManager.TtsMode.CLOUD && credits <= 0) {
+                                                        if (BuildConfig.FLAVOR != "oss" && currentTtsMode == TtsPlaybackManager.TtsMode.CLOUD && credits <= 0) {
                                                             showInsufficientCreditsDialog = true
                                                             ttsShouldStartOnChapterLoad = false
                                                             return@launch
@@ -3483,6 +3575,7 @@ fun EpubReaderHost(
                                                             chapterTitle = chapterTitle,
                                                             coverImageUri = coverUriString,
                                                             chapterIndex = targetChapterIndex,
+                                                            totalChapters = chapters.size,
                                                             ttsMode = currentTtsMode,
                                                             playbackSource = "READER",
                                                             authToken = token
@@ -3528,6 +3621,7 @@ fun EpubReaderHost(
 
                                                     summarizeBookContent(
                                                         content = content,
+                                                        context = context,
                                                         authToken = token,
                                                         onUsageReceived = { cost: Double?, freeRemaining: Int? ->
                                                             currentCost = cost
@@ -3779,11 +3873,14 @@ fun EpubReaderHost(
                     }
 
                     RenderMode.PAGINATED -> {
-                        val contentBottomPadding = if (pageInfoMode != PageInfoMode.HIDDEN) PAGE_INFO_BAR_HEIGHT else 0.dp
+                        val pageInfoReserve = if (pageInfoMode != PageInfoMode.HIDDEN) pageInfoBarHeight else 0.dp
+                        val contentTopPadding = if (pageInfoPosition == PageInfoPosition.TOP) pageInfoReserve else 0.dp
+                        val contentBottomPadding = if (pageInfoPosition == PageInfoPosition.BOTTOM) pageInfoReserve else 0.dp
 
                         BoxWithConstraints(
                             modifier = Modifier
                                 .fillMaxSize()
+                                .padding(top = contentTopPadding)
                                 .padding(bottom = contentBottomPadding)
                                 .testTag("ReaderContainer")
                         ) {
@@ -3799,6 +3896,7 @@ fun EpubReaderHost(
                                 paragraphGapMultiplier = currentParagraphGap,
                                 imageSizeMultiplier = currentImageSize,
                                 horizontalMarginMultiplier = currentHorizontalMargin,
+                                verticalMarginMultiplier = currentVerticalMargin,
                                 fontFamily = activeFontFamily,
                                 textAlign = currentTextAlign,
                                 activeHighlightPalette = currentHighlightPalette,
@@ -3810,6 +3908,7 @@ fun EpubReaderHost(
                                     offset = ttsState.startOffsetInSource
                                 ).takeIf { ttsState.currentText != null && ttsState.sourceCfi != null && ttsState.startOffsetInSource != -1 },
                                 activeTextureId = activeTextureId,
+                                activeTextureAlpha = activeTextureAlpha,
                                 initialChapterIndexInBook = lastKnownLocator?.chapterIndex,
                                 modifier = Modifier.alpha(if (isPagerInitialized) 1f else 0f),
                                 onPaginatorReady = { newPaginator ->
@@ -4094,17 +4193,19 @@ fun EpubReaderHost(
 
                 // Page Info Bar (Vertical)
                 AnimatedVisibility(
-                    visible = renderMode == RenderMode.VERTICAL_SCROLL && isPageInfoVisible,
+                    visible = currentRenderMode == RenderMode.VERTICAL_SCROLL && isPageInfoVisible,
                     enter = fadeIn(animationSpec = tween(200)),
                     exit = fadeOut(animationSpec = tween(200)),
-                    modifier = Modifier.align(Alignment.BottomCenter)
+                    modifier = Modifier.align(
+                        if (pageInfoPosition == PageInfoPosition.TOP) Alignment.TopCenter else Alignment.BottomCenter
+                    )
                 ) {
                     Box(
                         modifier = Modifier
                             .fillMaxWidth()
-                            .height(PAGE_INFO_BAR_HEIGHT)
+                            .height(pageInfoBarHeight)
                             .background(infoBarBgColor)
-                            .padding(bottom = bottomPadding + pageInfoBottomPadding)
+                            .then(activeTextureModifier)
                             .padding(horizontal = 16.dp),
                         contentAlignment = Alignment.Center
                     ) {
@@ -4140,17 +4241,19 @@ fun EpubReaderHost(
 
                 // Page Info Bar (Paginated)
                 AnimatedVisibility(
-                    visible = renderMode == RenderMode.PAGINATED && paginator != null && isPageInfoVisible && paginatedPagerState.pageCount > 0,
+                    visible = currentRenderMode == RenderMode.PAGINATED && paginator != null && isPageInfoVisible && paginatedPagerState.pageCount > 0,
                     enter = fadeIn(animationSpec = tween(200)),
                     exit = fadeOut(animationSpec = tween(200)),
-                    modifier = Modifier.align(Alignment.BottomCenter)
+                    modifier = Modifier.align(
+                        if (pageInfoPosition == PageInfoPosition.TOP) Alignment.TopCenter else Alignment.BottomCenter
+                    )
                 ) {
                     Box(
                         modifier = Modifier
                             .fillMaxWidth()
-                            .height(PAGE_INFO_BAR_HEIGHT)
+                            .height(pageInfoBarHeight)
                             .background(infoBarBgColor)
-                            .padding(bottom = bottomPadding + pageInfoBottomPadding)
+                            .then(activeTextureModifier)
                             .padding(horizontal = 16.dp),
                         contentAlignment = Alignment.Center
                     ) {
@@ -4442,6 +4545,8 @@ fun EpubReaderHost(
                     volumeScrollEnabled = volumeScrollEnabled,
                     isPageTurnAnimationEnabled = isPageTurnAnimationEnabled,
                     hiddenTools = hiddenTools,
+                    toolOrder = toolOrder,
+                    bottomTools = bottomTools,
                     onCustomizeTools = { showCustomizeToolsSheet = true },
                     onNavigateBack = { triggerSaveAndExit() },
                     isKeepScreenOn = isKeepScreenOn,
@@ -4522,6 +4627,71 @@ fun EpubReaderHost(
                     onOpenDictionarySettings = { showDictionarySettingsSheet = true },
                     onOpenThemeSettings = { showThemePanel = true },
                     onOpenVisualOptions = { showVisualOptionsSheet = true },
+                    onOpenAiHub = { showAiHubSheet = true },
+                    onOpenSlider = {
+                        when (currentRenderMode) {
+                            RenderMode.VERTICAL_SCROLL -> {
+                                sliderStartPage = currentPageInChapter
+                                sliderCurrentPage = currentPageInChapter.toFloat()
+                                isPageSliderVisible = true
+                                showBars = false
+                                scope.launch {
+                                    webViewRefForTts?.let { webView ->
+                                        startPageThumbnail = captureWebViewVisibleArea(webView)
+                                    }
+                                }
+                            }
+                            RenderMode.PAGINATED -> {
+                                if (paginatedPagerState.pageCount > 0) {
+                                    sliderStartPage = paginatedPagerState.currentPage + 1
+                                    sliderCurrentPage = (paginatedPagerState.currentPage + 1).toFloat()
+                                    isPageSliderVisible = true
+                                    showBars = false
+                                    startPageThumbnail = null
+                                } else {
+                                    bannerMessage = BannerMessage("Book is not paginated yet.")
+                                }
+                            }
+                        }
+                    },
+                    onOpenDrawer = {
+                        scope.launch { drawerState.open() }
+                    },
+                    onToggleFormat = {
+                        showFormatAdjustmentBars = !showFormatAdjustmentBars
+                        if (showFormatAdjustmentBars) {
+                            searchState.showSearchResultsPanel = false
+                            isPageSliderVisible = false
+                        }
+                    },
+                    onToggleSearch = {
+                        searchState.isSearchActive = true
+                        searchState.showSearchResultsPanel = true
+                        showBars = true
+                        showFormatAdjustmentBars = false
+                    },
+                    onToggleTts = {
+                        if (isTtsSessionActive) {
+                            Timber.d("TTS button clicked: Stopping TTS")
+                            userStoppedTts = true
+                            ttsController.stop()
+                        } else {
+                            when {
+                                ContextCompat.checkSelfPermission(
+                                    context,
+                                    Manifest.permission.POST_NOTIFICATIONS
+                                ) == PackageManager.PERMISSION_GRANTED -> {
+                                    startTts()
+                                }
+                                activity?.shouldShowRequestPermissionRationale(Manifest.permission.POST_NOTIFICATIONS) == true -> {
+                                    showPermissionRationaleDialog = true
+                                }
+                                else -> {
+                                    permissionLauncher.launch(Manifest.permission.POST_NOTIFICATIONS)
+                                }
+                            }
+                        }
+                    },
                     onToggleReflow = if (onToggleReflow != null) {
                         {
                             val activeChapter = if (currentRenderMode == RenderMode.PAGINATED) {
@@ -4687,8 +4857,12 @@ fun EpubReaderHost(
                     ttsState = ttsState,
                     isProUser = isProUser,
                     hiddenTools = hiddenTools,
+                    toolOrder = toolOrder,
+                    bottomTools = bottomTools,
                     currentTtsMode = currentTtsMode,
                     onOpenAiHub = { showAiHubSheet = true },
+                    onOpenDictionarySettings = { showDictionarySettingsSheet = true },
+                    onOpenThemeSettings = { showThemePanel = true },
                     onOpenSlider = {
                         when (currentRenderMode) {
                             RenderMode.VERTICAL_SCROLL -> {
@@ -4770,6 +4944,8 @@ fun EpubReaderHost(
                     onImageSizeChange = { currentImageSize = it },
                     currentHorizontalMargin = currentHorizontalMargin,
                     onHorizontalMarginChange = { currentHorizontalMargin = it },
+                    currentVerticalMargin = currentVerticalMargin,
+                    onVerticalMarginChange = { currentVerticalMargin = it },
                     currentFont = currentFontFamily,
                     currentCustomFontName = if(currentCustomFontPath != null) {
                         customFonts.find { it.path == currentCustomFontPath }?.displayName ?: "Custom Font"
@@ -4788,6 +4964,7 @@ fun EpubReaderHost(
                         currentParagraphGap = DEFAULT_PARAGRAPH_GAP_VAL
                         currentImageSize = DEFAULT_IMAGE_SIZE_VAL
                         currentHorizontalMargin = DEFAULT_HORIZONTAL_MARGIN_VAL
+                        currentVerticalMargin = DEFAULT_VERTICAL_MARGIN_VAL
                         currentFontFamily = ReaderFont.ORIGINAL
                         currentCustomFontPath = null
                         currentTextAlign = ReaderTextAlign.DEFAULT
@@ -5085,10 +5262,20 @@ fun EpubReaderHost(
         if (showCustomizeToolsSheet) {
             CustomizeToolsSheet(
                 hiddenTools = hiddenTools,
+                toolOrder = toolOrder,
+                bottomTools = bottomTools,
                 onUpdate = { newHiddenSet ->
                     hiddenTools = newHiddenSet
                     saveHiddenTools(context, newHiddenSet)
                 },
+                onOrderUpdate = { newOrder ->
+                    toolOrder = newOrder
+                    saveToolOrder(context, newOrder)
+                },
+                onPlacementUpdate = { newBottomTools ->
+                    bottomTools = newBottomTools
+                    saveBottomTools(context, newBottomTools)
+                },
                 onDismiss = { showCustomizeToolsSheet = false }
             )
         }
@@ -5133,6 +5320,11 @@ fun EpubReaderHost(
                     pageInfoMode = it
                     savePageInfoMode(context, it)
                 },
+                pageInfoPosition = pageInfoPosition,
+                onPageInfoPositionChange = {
+                    pageInfoPosition = it
+                    savePageInfoPosition(context, it)
+                },
                 pullToTurnEnabled = pullToTurnEnabled,
                 onPullToTurnChange = {
                     pullToTurnEnabled = it
@@ -5173,6 +5365,11 @@ fun EpubReaderHost(
             ReaderThemePanel(
                 isVisible = true,
                 currentThemeId = currentThemeId,
+                globalTextureTransparency = globalTextureTransparency,
+                onGlobalTextureTransparencyChange = {
+                    globalTextureTransparency = it
+                    saveGlobalTextureTransparency(context, it)
+                },
                 onThemeSelected = {
                     currentThemeId = it
                     saveReaderThemeId(context, it)

app/src/main/java/com/aryan/reader/epubreader/EpubReaderSettings.kt

@@ -120,6 +120,7 @@ private const val TAP_TO_NAVIGATE_ENABLED_KEY = "tap_to_navigate_enabled"
 private const val VOLUME_SCROLL_ENABLED_KEY = "volume_scroll_enabled"
 private const val SYSTEM_UI_MODE_KEY = "reader_system_ui_mode"
 private const val PAGE_INFO_MODE_KEY = "reader_page_info_mode"
+private const val PAGE_INFO_POSITION_KEY = "reader_page_info_position"
 private const val PULL_TO_TURN_ENABLED_KEY = "reader_pull_to_turn_enabled"
 
 const val DEFAULT_FONT_SIZE_VAL = 1.0f
@@ -127,6 +128,7 @@ const val DEFAULT_LINE_HEIGHT_VAL = 1.0f
 const val DEFAULT_PARAGRAPH_GAP_VAL = 1.0f
 const val DEFAULT_IMAGE_SIZE_VAL = 1.0f
 const val DEFAULT_HORIZONTAL_MARGIN_VAL = 1.0f
+const val DEFAULT_VERTICAL_MARGIN_VAL = 1.0f
 private const val TTS_SPEECH_RATE_KEY = "tts_speech_rate"
 private const val TTS_PITCH_KEY = "tts_pitch"
 
@@ -177,12 +179,18 @@ enum class PageInfoMode(val id: Int, val title: String) {
     HIDDEN(2, "Always Hide")
 }
 
+enum class PageInfoPosition(val id: Int, val title: String) {
+    BOTTOM(0, "Bottom"),
+    TOP(1, "Top")
+}
+
 data class FormatSettings(
     val fontSize: Float,
     val lineHeight: Float,
     val paragraphGap: Float,
     val imageSize: Float,
     val horizontalMargin: Float,
+    val verticalMargin: Float,
     val font: ReaderFont,
     val customPath: String?,
     val textAlign: ReaderTextAlign
@@ -194,9 +202,11 @@ private const val LOCAL_LINE_HEIGHT_PREFIX = "local_line_height_"
 private const val LOCAL_PARAGRAPH_GAP_PREFIX = "local_paragraph_gap_"
 private const val LOCAL_IMAGE_SIZE_PREFIX = "local_image_size_"
 private const val LOCAL_HORIZONTAL_MARGIN_PREFIX = "local_horizontal_margin_"
+private const val LOCAL_VERTICAL_MARGIN_PREFIX = "local_vertical_margin_"
 private const val LOCAL_FONT_FAMILY_PREFIX = "local_font_family_"
 private const val LOCAL_TEXT_ALIGN_PREFIX = "local_text_align_"
 private const val HORIZONTAL_MARGIN_KEY = "reader_horizontal_margin"
+private const val VERTICAL_MARGIN_KEY = "reader_vertical_margin"
 
 fun loadFormatIsLocal(context: Context, bookId: String): Boolean {
     val prefs = context.getSharedPreferences(SETTINGS_PREFS_NAME, Context.MODE_PRIVATE)
@@ -216,6 +226,7 @@ fun saveLocalReaderSettings(
     paragraphGap: Float,
     imageSize: Float,
     horizontalMargin: Float,
+    verticalMargin: Float,
     fontFamily: ReaderFont,
     customFontPath: String?,
     textAlign: ReaderTextAlign
@@ -227,6 +238,7 @@ fun saveLocalReaderSettings(
         putFloat(LOCAL_PARAGRAPH_GAP_PREFIX + bookId, paragraphGap)
         putFloat(LOCAL_IMAGE_SIZE_PREFIX + bookId, imageSize)
         putFloat(LOCAL_HORIZONTAL_MARGIN_PREFIX + bookId, horizontalMargin)
+        putFloat(LOCAL_VERTICAL_MARGIN_PREFIX + bookId, verticalMargin)
         if (customFontPath != null) {
             putString(LOCAL_FONT_FAMILY_PREFIX + bookId, "custom|$customFontPath")
         } else {
@@ -258,6 +270,17 @@ fun loadPageInfoMode(context: Context): PageInfoMode {
     return PageInfoMode.entries.find { it.id == id } ?: PageInfoMode.DEFAULT
 }
 
+fun savePageInfoPosition(context: Context, position: PageInfoPosition) {
+    val prefs = context.getSharedPreferences(SETTINGS_PREFS_NAME, Context.MODE_PRIVATE)
+    prefs.edit { putInt(PAGE_INFO_POSITION_KEY, position.id) }
+}
+
+fun loadPageInfoPosition(context: Context): PageInfoPosition {
+    val prefs = context.getSharedPreferences(SETTINGS_PREFS_NAME, Context.MODE_PRIVATE)
+    val id = prefs.getInt(PAGE_INFO_POSITION_KEY, PageInfoPosition.BOTTOM.id)
+    return PageInfoPosition.entries.find { it.id == id } ?: PageInfoPosition.BOTTOM
+}
+
 fun savePullToTurn(context: Context, enabled: Boolean) {
     val prefs = context.getSharedPreferences(SETTINGS_PREFS_NAME, Context.MODE_PRIVATE)
     prefs.edit { putBoolean(PULL_TO_TURN_ENABLED_KEY, enabled) }
@@ -288,6 +311,11 @@ fun loadHorizontalMargin(context: Context): Float {
     return if (loadRemoveEdgePadding(context)) 0f else DEFAULT_HORIZONTAL_MARGIN_VAL
 }
 
+fun loadVerticalMargin(context: Context): Float {
+    val prefs = context.getSharedPreferences(SETTINGS_PREFS_NAME, Context.MODE_PRIVATE)
+    return prefs.getFloat(VERTICAL_MARGIN_KEY, DEFAULT_VERTICAL_MARGIN_VAL)
+}
+
 fun loadFormatSettings(context: Context, bookId: String, isLocal: Boolean): FormatSettings {
     val prefs = context.getSharedPreferences(SETTINGS_PREFS_NAME, Context.MODE_PRIVATE)
 
@@ -321,6 +349,12 @@ fun loadFormatSettings(context: Context, bookId: String, isLocal: Boolean): Form
         loadHorizontalMargin(context)
     }
 
+    val verticalMargin = if (isLocal && prefs.contains(LOCAL_VERTICAL_MARGIN_PREFIX + bookId)) {
+        prefs.getFloat(LOCAL_VERTICAL_MARGIN_PREFIX + bookId, DEFAULT_VERTICAL_MARGIN_VAL)
+    } else {
+        loadVerticalMargin(context)
+    }
+
     val savedFontVal = if (isLocal && prefs.contains(LOCAL_FONT_FAMILY_PREFIX + bookId)) {
         prefs.getString(LOCAL_FONT_FAMILY_PREFIX + bookId, ReaderFont.ORIGINAL.id) ?: ReaderFont.ORIGINAL.id
     } else {
@@ -346,6 +380,7 @@ fun loadFormatSettings(context: Context, bookId: String, isLocal: Boolean): Form
         paragraphGap = paragraphGap,
         imageSize = imageSize,
         horizontalMargin = horizontalMargin,
+        verticalMargin = verticalMargin,
         font = font,
         customPath = customPath,
         textAlign = textAlign
@@ -390,6 +425,7 @@ fun saveReaderSettings(
     paragraphGap: Float,
     imageSize: Float,
     horizontalMargin: Float,
+    verticalMargin: Float,
     fontFamily: ReaderFont,
     customFontPath: String?,
     textAlign: ReaderTextAlign
@@ -401,6 +437,7 @@ fun saveReaderSettings(
         putFloat(PARAGRAPH_GAP_KEY, paragraphGap)
         putFloat(IMAGE_SIZE_KEY, imageSize)
         putFloat(HORIZONTAL_MARGIN_KEY, horizontalMargin)
+        putFloat(VERTICAL_MARGIN_KEY, verticalMargin)
         if (customFontPath != null) {
             putString(FONT_FAMILY_KEY, "custom|$customFontPath")
         } else {
@@ -454,6 +491,8 @@ fun ReaderTextFormatPanel(
     onImageSizeChange: (Float) -> Unit,
     currentHorizontalMargin: Float,
     onHorizontalMarginChange: (Float) -> Unit,
+    currentVerticalMargin: Float,
+    onVerticalMarginChange: (Float) -> Unit,
     currentFont: ReaderFont,
     currentCustomFontName: String?,
     onFontOptionClick: () -> Unit,
@@ -699,6 +738,20 @@ fun ReaderTextFormatPanel(
                             }
                         }
                     )
+
+                    FormatSlider(
+                        label = stringResource(R.string.label_vertical_margin),
+                        value = currentVerticalMargin,
+                        onValueChange = onVerticalMarginChange,
+                        valueRange = 0.0f..3.0f,
+                        formatValue = {
+                            when {
+                                it <= 0.01f -> noneLabel
+                                it in 0.99f..1.01f -> originalLabel
+                                else -> "%.1fx".format(it)
+                            }
+                        }
+                    )
                 }
             }
         }
@@ -830,6 +883,8 @@ fun VisualOptionsSheet(
     onSystemUiModeChange: (SystemUiMode) -> Unit,
     pageInfoMode: PageInfoMode,
     onPageInfoModeChange: (PageInfoMode) -> Unit,
+    pageInfoPosition: PageInfoPosition,
+    onPageInfoPositionChange: (PageInfoPosition) -> Unit,
     pullToTurnEnabled: Boolean,
     onPullToTurnChange: (Boolean) -> Unit,
     pullToTurnMultiplier: Float,
@@ -884,6 +939,16 @@ fun VisualOptionsSheet(
                 getLabel = { it.title }
             )
 
+            Spacer(modifier = Modifier.height(16.dp))
+            Text(stringResource(R.string.visual_options_progress_bar_position), style = MaterialTheme.typography.titleSmall)
+            Spacer(modifier = Modifier.height(8.dp))
+            OptionSegmentedControl(
+                options = PageInfoPosition.entries,
+                selectedOption = pageInfoPosition,
+                onOptionSelected = onPageInfoPositionChange,
+                getLabel = { it.title }
+            )
+
             Spacer(modifier = Modifier.height(24.dp))
 
             // Pull to change chapter

app/src/main/java/com/aryan/reader/epubreader/EpubReaderSystem.kt

@@ -20,6 +20,7 @@
 package com.aryan.reader.epubreader
 
 import timber.log.Timber
+import android.graphics.Color
 import android.view.KeyEvent
 import android.view.View
 import android.view.Window
@@ -51,14 +52,20 @@ fun EpubReaderSystemUiController(
             return@DisposableEffect onDispose {}
         }
         val insetsController = WindowCompat.getInsetsController(window, view)
+        val originalStatusBarColor = window.statusBarColor
+        val originalNavigationBarColor = window.navigationBarColor
         Timber.d("Applying immersive mode.")
 
         WindowCompat.setDecorFitsSystemWindows(window, false)
+        window.statusBarColor = Color.TRANSPARENT
+        window.navigationBarColor = Color.TRANSPARENT
         insetsController.systemBarsBehavior = WindowInsetsControllerCompat.BEHAVIOR_SHOW_TRANSIENT_BARS_BY_SWIPE
 
         onDispose {
             Timber.d("Restoring system UI.")
             WindowCompat.setDecorFitsSystemWindows(window, true)
+            window.statusBarColor = originalStatusBarColor
+            window.navigationBarColor = originalNavigationBarColor
             insetsController.show(WindowInsetsCompat.Type.navigationBars() or WindowInsetsCompat.Type.statusBars())
             insetsController.isAppearanceLightStatusBars = initialIsAppearanceLightStatusBars
             insetsController.systemBarsBehavior = initialSystemBarsBehavior

app/src/main/java/com/aryan/reader/epubreader/EpubReaderTts.kt

@@ -328,6 +328,8 @@ private fun handleVerticalAutoAdvance(
                         chapterTitle = chapters.getOrNull(currentTtsChapterIndex)?.title,
                         coverImageUri = coverImagePath?.let { android.net.Uri.fromFile(File(it)).toString() },
                         chapterIndex = currentTtsChapterIndex,
+                        totalChapters = chapters.size,
+                        continueSession = true,
                         ttsMode = currentTtsMode,
                         playbackSource = "READER",
                         authToken = token
@@ -358,6 +360,8 @@ private fun handleVerticalAutoAdvance(
                     chapterTitle = chapters.getOrNull(nextIdx)?.title,
                     coverImageUri = coverImagePath?.let { Uri.fromFile(File(it)).toString() },
                     chapterIndex = nextIdx,
+                    totalChapters = chapters.size,
+                    continueSession = true,
                     ttsMode = currentTtsMode,
                     playbackSource = "READER",
                     authToken = token
@@ -433,6 +437,8 @@ private fun handlePaginatedAutoAdvance(
                         chapterTitle = chapterTitle,
                         coverImageUri = coverUriString,
                         chapterIndex = chapterToTry,
+                        totalChapters = chapters.size,
+                        continueSession = true,
                         ttsMode = ttsMode,
                         playbackSource = "READER",
                         authToken = token

app/src/main/java/com/aryan/reader/feedback/SupportProjectScreen.kt

@@ -0,0 +1,172 @@
+package com.aryan.reader.feedback
+
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.ArrowBack
+import androidx.compose.material.icons.automirrored.filled.ArrowForward
+import androidx.compose.material.icons.outlined.FavoriteBorder
+import androidx.compose.material3.ExperimentalMaterial3Api
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.OutlinedCard
+import androidx.compose.material3.Scaffold
+import androidx.compose.material3.Text
+import androidx.compose.material3.TopAppBar
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.platform.LocalUriHandler
+import androidx.compose.ui.res.painterResource
+import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.text.style.TextAlign
+import androidx.compose.ui.unit.dp
+import androidx.navigation.NavHostController
+import com.aryan.reader.R
+
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+fun SupportProjectScreen(
+    navController: NavHostController
+) {
+    val uriHandler = LocalUriHandler.current
+
+    Scaffold(
+        topBar = {
+            TopAppBar(
+                title = { Text(stringResource(R.string.support_project_title)) },
+                navigationIcon = {
+                    IconButton(onClick = { navController.popBackStack() }) {
+                        Icon(Icons.AutoMirrored.Filled.ArrowBack, contentDescription = stringResource(R.string.action_back))
+                    }
+                }
+            )
+        }
+    ) { paddingValues ->
+        Column(
+            modifier = Modifier
+                .fillMaxSize()
+                .padding(paddingValues)
+                .padding(horizontal = 16.dp),
+            horizontalAlignment = Alignment.CenterHorizontally
+        ) {
+            Spacer(modifier = Modifier.height(32.dp))
+
+            Icon(
+                imageVector = Icons.Outlined.FavoriteBorder,
+                contentDescription = null,
+                modifier = Modifier.size(72.dp),
+                tint = MaterialTheme.colorScheme.primary
+            )
+
+            Spacer(modifier = Modifier.height(16.dp))
+
+            Text(
+                text = stringResource(R.string.support_project_heading),
+                style = MaterialTheme.typography.headlineMedium,
+                fontWeight = FontWeight.Bold
+            )
+
+            Spacer(modifier = Modifier.height(8.dp))
+
+            Text(
+                text = stringResource(R.string.support_project_desc),
+                style = MaterialTheme.typography.bodyLarge,
+                textAlign = TextAlign.Center,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+                modifier = Modifier.padding(horizontal = 16.dp)
+            )
+
+            Spacer(modifier = Modifier.height(48.dp))
+
+            SupportOptionCard(
+                title = stringResource(R.string.support_github_sponsor),
+                description = stringResource(R.string.support_github_sponsor_desc),
+                icon = {
+                    Icon(
+                        painter = painterResource(id = R.drawable.github),
+                        contentDescription = stringResource(R.string.support_github_sponsor),
+                        modifier = Modifier.size(28.dp),
+                        tint = MaterialTheme.colorScheme.primary
+                    )
+                },
+                onClick = {
+                    uriHandler.openUri("https://github.com/sponsors/Aryan-Raj3112")
+                }
+            )
+
+            Spacer(modifier = Modifier.height(16.dp))
+
+            SupportOptionCard(
+                title = stringResource(R.string.support_patreon),
+                description = stringResource(R.string.support_patreon_desc),
+                icon = {
+                    Icon(
+                        imageVector = Icons.Outlined.FavoriteBorder,
+                        contentDescription = stringResource(R.string.support_patreon),
+                        modifier = Modifier.size(28.dp),
+                        tint = MaterialTheme.colorScheme.primary
+                    )
+                },
+                onClick = {
+                    uriHandler.openUri("https://www.patreon.com/c/epistemereader")
+                }
+            )
+
+            Spacer(modifier = Modifier.weight(1f))
+        }
+    }
+}
+
+@Composable
+private fun SupportOptionCard(
+    title: String,
+    description: String,
+    icon: @Composable () -> Unit,
+    onClick: () -> Unit
+) {
+    OutlinedCard(
+        onClick = onClick,
+        modifier = Modifier.fillMaxWidth(),
+        shape = RoundedCornerShape(16.dp)
+    ) {
+        Row(
+            modifier = Modifier
+                .fillMaxWidth()
+                .padding(20.dp),
+            verticalAlignment = Alignment.CenterVertically
+        ) {
+            icon()
+            Spacer(modifier = Modifier.width(20.dp))
+            Column(modifier = Modifier.weight(1f)) {
+                Text(
+                    text = title,
+                    style = MaterialTheme.typography.titleMedium,
+                    fontWeight = FontWeight.Bold
+                )
+                Spacer(modifier = Modifier.height(4.dp))
+                Text(
+                    text = description,
+                    style = MaterialTheme.typography.bodyMedium,
+                    color = MaterialTheme.colorScheme.onSurfaceVariant
+                )
+            }
+            Spacer(modifier = Modifier.width(8.dp))
+            Icon(
+                imageVector = Icons.AutoMirrored.Filled.ArrowForward,
+                contentDescription = stringResource(R.string.action_open),
+                tint = MaterialTheme.colorScheme.onSurfaceVariant
+            )
+        }
+    }
+}

app/src/main/java/com/aryan/reader/opds/OpdsModels.kt

@@ -38,6 +38,8 @@ data class OpdsAcquisition(
         get() = when {
             mimeType.contains("epub") -> "EPUB"
             mimeType.contains("pdf") -> "PDF"
+            mimeType.contains("markdown") || mimeType.contains("text/x-markdown") -> "MD"
+            mimeType.contains("html") || mimeType.contains("xhtml") -> "HTML"
             mimeType.contains("mobi") || mimeType.contains("x-mobipocket-ebook") -> "MOBI"
             mimeType.contains("fictionbook") || mimeType.contains("fb2") -> "FB2"
             mimeType.contains("cbz") || mimeType.contains("comicbook") -> "CBZ"
@@ -52,6 +54,7 @@ data class OpdsAcquisition(
             "PDF" -> 4
             "MOBI" -> 3
             "FB2" -> 2
+            "MD", "HTML" -> 2
             "CBZ" -> 1
             "TXT" -> 0
             else -> -1

app/src/main/java/com/aryan/reader/opds/OpdsViewModel.kt

@@ -5,6 +5,7 @@ import android.content.Context
 import android.net.Uri
 import androidx.lifecycle.AndroidViewModel
 import androidx.lifecycle.viewModelScope
+import com.aryan.reader.resolveFileExtensionSuffixFromName
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
@@ -12,6 +13,7 @@ import kotlinx.coroutines.flow.asStateFlow
 import kotlinx.coroutines.flow.update
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
+import okhttp3.Response
 import okhttp3.Request
 import timber.log.Timber
 import java.io.File
@@ -93,16 +95,7 @@ class OpdsViewModel(application: Application) : AndroidViewModel(application) {
                     val body = response.body ?: throw Exception("Empty body")
                     val contentLength = body.contentLength()
 
-                    val ext = when (acquisition.formatName) {
-                        "EPUB" -> ".epub"
-                        "PDF" -> ".pdf"
-                        "MOBI" -> ".mobi"
-                        "FB2" -> ".fb2"
-                        "CBZ" -> ".cbz"
-                        "CBR" -> ".cbr"
-                        "TXT" -> ".txt"
-                        else -> ".epub"
-                    }
+                    val ext = resolveOpdsDownloadExtension(acquisition, response)
 
                     val safeTitle = entry.title.replace(Regex("[^a-zA-Z0-9.-]"), "_").take(50)
                     val tempFile = File(context.cacheDir, "opds_dl_${safeTitle}$ext")
@@ -148,6 +141,45 @@ class OpdsViewModel(application: Application) : AndroidViewModel(application) {
         }
     }
 
+    private fun resolveOpdsDownloadExtension(acquisition: OpdsAcquisition, response: Response): String {
+        val candidates = listOfNotNull(
+            response.header("Content-Disposition")?.let(::extractContentDispositionFilename),
+            Uri.parse(acquisition.url).lastPathSegment
+        )
+
+        candidates.forEach { candidate ->
+            resolveFileExtensionSuffixFromName(Uri.decode(candidate))?.let { return it }
+        }
+
+        return when (acquisition.formatName) {
+            "EPUB" -> ".epub"
+            "PDF" -> ".pdf"
+            "MOBI" -> ".mobi"
+            "FB2" -> ".fb2"
+            "CBZ" -> ".cbz"
+            "CBR" -> ".cbr"
+            "MD" -> ".md"
+            "HTML" -> ".html"
+            "TXT" -> ".txt"
+            else -> ".epub"
+        }
+    }
+
+    private fun extractContentDispositionFilename(contentDisposition: String): String? {
+        val encodedFilename = Regex("filename\\*=UTF-8''([^;]+)", RegexOption.IGNORE_CASE)
+            .find(contentDisposition)
+            ?.groupValues
+            ?.getOrNull(1)
+        if (!encodedFilename.isNullOrBlank()) return encodedFilename.trim('"')
+
+        return Regex("filename=\"?([^\";]+)\"?", RegexOption.IGNORE_CASE)
+            .find(contentDisposition)
+            ?.groupValues
+            ?.getOrNull(1)
+            ?.trim()
+            ?.trim('"')
+    }
+
     init {
         loadCatalogs()
     }

app/src/main/java/com/aryan/reader/paginatedreader/AndroidHtmlParserPlatform.kt

@@ -0,0 +1,81 @@
+package com.aryan.reader.paginatedreader
+
+import android.graphics.BitmapFactory
+import androidx.compose.ui.text.font.FontFamily
+import java.io.File
+import java.net.URLDecoder
+import java.nio.file.Paths
+
+object AndroidHtmlResourceResolver : HtmlResourceResolver {
+    override fun resolvePath(chapterAbsPath: String, extractionBasePath: String, src: String): String? {
+        if (src.isBlank()) return null
+        val decodedSrc = try {
+            URLDecoder.decode(src, "UTF-8")
+        } catch (_: Exception) {
+            src
+        }
+        val parentPath = File(chapterAbsPath).parent ?: ""
+        val relativePath = Paths.get(parentPath, decodedSrc).normalize().toString()
+        val fromRelativeFile = File(extractionBasePath, relativePath)
+
+        return try {
+            when {
+                fromRelativeFile.exists() -> fromRelativeFile.canonicalFile.absolutePath
+                File(extractionBasePath, decodedSrc).exists() -> File(extractionBasePath, decodedSrc).canonicalFile.absolutePath
+                else -> null
+            }
+        } catch (_: Exception) {
+            null
+        }
+    }
+
+    override fun readText(path: String): String? {
+        return runCatching { File(path).readText() }.getOrNull()
+    }
+
+    override fun imageDimensions(path: String): Pair<Float?, Float?>? {
+        return runCatching {
+            val options = BitmapFactory.Options().apply { inJustDecodeBounds = true }
+            BitmapFactory.decodeFile(path, options)
+            if (options.outWidth > 0 && options.outHeight > 0) {
+                options.outWidth.toFloat() to options.outHeight.toFloat()
+            } else {
+                null
+            }
+        }.getOrNull()
+    }
+}
+
+object AndroidHtmlFontFamilyLoader : HtmlFontFamilyLoader {
+    override fun load(fontFaces: List<FontFaceInfo>, extractionBasePath: String): Map<String, FontFamily> {
+        return loadFontFamilies(fontFaces, extractionBasePath)
+    }
+}
+
+fun androidHtmlToSemanticBlocks(
+    html: String,
+    cssRules: OptimizedCssRules,
+    textStyle: androidx.compose.ui.text.TextStyle,
+    chapterAbsPath: String,
+    extractionBasePath: String,
+    density: androidx.compose.ui.unit.Density,
+    fontFamilyMap: Map<String, FontFamily>,
+    constraints: androidx.compose.ui.unit.Constraints,
+    imageDimensionsCache: Map<String, Pair<Float, Float>> = emptyMap(),
+    mathSvgCache: Map<String, String> = emptyMap()
+): List<SemanticBlock> {
+    return htmlToSemanticBlocks(
+        html = html,
+        cssRules = cssRules,
+        textStyle = textStyle,
+        chapterAbsPath = chapterAbsPath,
+        extractionBasePath = extractionBasePath,
+        density = density,
+        fontFamilyMap = fontFamilyMap,
+        constraints = constraints,
+        imageDimensionsCache = imageDimensionsCache,
+        mathSvgCache = mathSvgCache,
+        resourceResolver = AndroidHtmlResourceResolver,
+        fontFamilyLoader = AndroidHtmlFontFamilyLoader
+    )
+}

app/src/main/java/com/aryan/reader/paginatedreader/BookPaginator.kt

@@ -120,7 +120,8 @@ class BookPaginator(
     private val mathMLRenderer: MathMLRenderer,
     private val userTextAlign: TextAlign?,
     private val paragraphGapMultiplier: Float,
-    private val imageSizeMultiplier: Float
+    private val imageSizeMultiplier: Float,
+    private val verticalMarginMultiplier: Float
 ) : IPaginator {
     override var totalPageCount by mutableIntStateOf(0)
         private set
@@ -185,6 +186,14 @@ class BookPaginator(
                 isLoading = true
                 Timber.d("Initialization started.")
 
+                if (chapters.isEmpty()) {
+                    totalPageCount = 0
+                    pageCountsAreAccurate = true
+                    isLoading = false
+                    Timber.w("Paginator initialized with no chapters. Skipping pagination startup.")
+                    return@launch
+                }
+
                 // 1. Book processing check (Keep existing logic)
                 val bookRecord = bookCacheDao.getProcessedBook(bookId)
                 if (bookRecord == null || bookRecord.processingVersion < LATEST_PROCESSING_VERSION) {
@@ -214,7 +223,7 @@ class BookPaginator(
                 // 5. Prioritize CURRENT chapter only
                 // We no longer blindly queue neighbors immediately to keep startup fast.
                 // We only queue the requested chapter.
-                val startChapter = initialChapterToPaginate.coerceIn(0, chapters.size - 1)
+                val startChapter = initialChapterToPaginate.coerceIn(0, chapters.lastIndex)
 
                 // Trigger actual pagination for the current chapter to replace the estimate with reality
                 triggerPagination(startChapter, PRIORITY_HIGHEST)
@@ -277,6 +286,7 @@ class BookPaginator(
             append("-ta:$userTextAlign")
             append("-pg:$paragraphGapMultiplier")
             append("-img:$imageSizeMultiplier")
+            append("-vm:$verticalMarginMultiplier")
         }
         val hash = configString.hashCode()
         return hash
@@ -503,7 +513,7 @@ class BookPaginator(
             parsingCssRules = parsingCssRules.merge(bookCssResult.rules)
         }
 
-        val semanticBlocks = htmlToSemanticBlocks(
+        val semanticBlocks = androidHtmlToSemanticBlocks(
             html = processedHtml,
             cssRules = parsingCssRules,
             textStyle = textStyle.copy(color = Color.Black),
@@ -792,6 +802,10 @@ class BookPaginator(
     }
 
     private fun triggerPagination(chapterIndex: Int, priority: Int) {
+        if (chapterIndex !in chapters.indices) {
+            Timber.w("Trigger: Ignoring invalid chapter index $chapterIndex. Chapter count: ${chapters.size}.")
+            return
+        }
         if (pageCache[chapterIndex] != null) {
             Timber.v("Trigger: Chapter $chapterIndex is already in cache. Ignoring.")
             return

app/src/main/java/com/aryan/reader/paginatedreader/ContentStyler.kt

@@ -163,10 +163,12 @@ class ContentStyler(
             }
 
             is SemanticMath -> {
+                val svgContent = block.svgContent
+                val nonBlankSvgContent = svgContent?.takeIf { it.isNotBlank() }
                 val finalSvgContent = when {
-                    block.isFromMathJax || block.svgContent.isNullOrBlank() -> block.svgContent
+                    block.isFromMathJax || nonBlankSvgContent == null -> svgContent
                     else -> {
-                        val themedSvg = applyThemeToSvg(block.svgContent)
+                        val themedSvg = applyThemeToSvg(nonBlankSvgContent)
                         embedImagesInSvg(themedSvg)
                     }
                 }
@@ -452,11 +454,11 @@ class ContentStyler(
                             }
                         }
 
-                        if (span.linkHref != null) {
-                            addStringAnnotation("URL", span.linkHref, span.start, span.end)
+                        span.linkHref?.let { linkHref ->
+                            addStringAnnotation("URL", linkHref, span.start, span.end)
                         }
-                        if (span.elementId != null) {
-                            addStringAnnotation("ID", span.elementId, span.start, span.end)
+                        span.elementId?.let { elementId ->
+                            addStringAnnotation("ID", elementId, span.start, span.end)
                         }
                     }
                 }

app/src/main/java/com/aryan/reader/paginatedreader/FontLoader.kt

@@ -27,47 +27,6 @@ import androidx.compose.ui.text.font.FontWeight
 import java.io.File
 import java.security.MessageDigest
 
-/**
- * A centralized mapper for handling conversions between generic CSS font family names
- * and Compose's FontFamily objects.
- */
-object FontFamilyMapper {
-    private val genericFontMap = mapOf(
-        "serif" to FontFamily.Serif,
-        "sans-serif" to FontFamily.SansSerif,
-        "monospace" to FontFamily.Monospace,
-        "cursive" to FontFamily.Cursive,
-        "default" to FontFamily.Default,
-        "system-ui" to FontFamily.Default,
-        "ui-sans-serif" to FontFamily.Default,
-        "ui-serif" to FontFamily.Default,
-        "ui-monospace" to FontFamily.Default,
-        "ui-rounded" to FontFamily.Default
-    )
-
-    /**
-     * Converts a string name (e.g., "serif") to a Compose [FontFamily].
-     */
-    fun nameToFontFamily(name: String): FontFamily? {
-        return genericFontMap[name.trim().lowercase()]
-    }
-
-    /**
-     * Converts a Compose [FontFamily] back to its primary string name for serialization.
-     * Custom fonts are not serialized by name and will return null.
-     */
-    fun fontFamilyToName(fontFamily: FontFamily): String? {
-        return when (fontFamily) {
-            FontFamily.Serif -> "serif"
-            FontFamily.SansSerif -> "sans-serif"
-            FontFamily.Monospace -> "monospace"
-            FontFamily.Cursive -> "cursive"
-            FontFamily.Default -> "default"
-            else -> null
-        }
-    }
-}
-
 private fun getCacheKeyForFont(bookId: String, fontPath: String): String {
     val identifier = "$bookId:$fontPath"
     val digest = MessageDigest.getInstance("MD5").digest(identifier.toByteArray())

app/src/main/java/com/aryan/reader/paginatedreader/Locator.kt

@@ -115,7 +115,7 @@ class LocatorConverter(
                 otherComplex = mergedOtherComplex
             )
 
-            val semanticBlocks = htmlToSemanticBlocks(
+            val semanticBlocks = androidHtmlToSemanticBlocks(
                 html = htmlToParse,
                 cssRules = parsingCssRules,
                 textStyle = TextStyle(),

app/src/main/java/com/aryan/reader/paginatedreader/PaginatedReader.kt

@@ -21,6 +21,7 @@ import androidx.compose.foundation.gestures.awaitEachGesture
 import androidx.compose.foundation.gestures.awaitFirstDown
 import androidx.compose.foundation.gestures.detectTapGestures
 import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.aspectRatio
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.BoxWithConstraints
 import androidx.compose.foundation.layout.Column
@@ -147,7 +148,7 @@ import coil.compose.AsyncImage
 import coil.imageLoader
 import coil.request.ImageRequest.Builder
 import com.aryan.reader.R
-import com.aryan.reader.ReaderTexture
+import com.aryan.reader.loadReaderTextureBitmap
 import com.aryan.reader.countWords
 import com.aryan.reader.epub.EpubBook
 import com.aryan.reader.epubreader.HighlightColor
@@ -251,6 +252,12 @@ private fun headerFontScale(level: Int): Float = when (level) {
     else -> 1.0f
 }
 
+private const val WEB_VIEW_NORMAL_LINE_HEIGHT_MULTIPLIER = 1.2f
+
+private fun paginationLineHeightMultiplierForWebViewSetting(multiplier: Float): Float {
+    return if (abs(multiplier - 1.0f) < 0.001f) WEB_VIEW_NORMAL_LINE_HEIGHT_MULTIPLIER else multiplier
+}
+
 private fun createHeaderTextStyle(
     baseStyle: TextStyle,
     level: Int,
@@ -473,6 +480,51 @@ private fun computeImageRenderSizeDp(
     return with(density) { widthPx.toDp() to heightPx.toDp() }
 }
 
+private fun imageBlockContentAlignment(style: BlockStyle): Alignment {
+    return when {
+        style.float == "right" || style.horizontalAlign == "right" || style.horizontalAlign == "end" -> Alignment.CenterEnd
+        style.float == "left" || style.horizontalAlign == "left" || style.horizontalAlign == "start" -> Alignment.CenterStart
+        else -> Alignment.Center
+    }
+}
+
+private fun tableCellImageModifier(
+    block: ImageBlock,
+    density: Density,
+    imageSizeMultiplier: Float
+): Modifier {
+    val baseModifier = if (block.style.width.isSpecified && block.style.width > 0.dp) {
+        Modifier.width(block.style.width * imageSizeMultiplier)
+    } else {
+        Modifier.fillMaxWidth(imageSizeMultiplier.coerceIn(0f, 1f))
+    }
+
+    val intrinsicWidth = block.intrinsicWidth
+    val intrinsicHeight = block.intrinsicHeight
+    val sizedModifier = if (
+        intrinsicWidth != null &&
+        intrinsicHeight != null &&
+        intrinsicWidth > 0f &&
+        intrinsicHeight > 0f
+    ) {
+        baseModifier.aspectRatio(intrinsicWidth / intrinsicHeight)
+    } else {
+        baseModifier.height(
+            if (block.expectedHeight > 0) {
+                with(density) { (block.expectedHeight * imageSizeMultiplier).toDp() }
+            } else {
+                250.dp
+            }
+        )
+    }
+
+    return if (block.style.maxWidth.isSpecified && block.style.maxWidth > 0.dp) {
+        sizedModifier.widthIn(max = block.style.maxWidth * imageSizeMultiplier)
+    } else {
+        sizedModifier
+    }
+}
+
 @Composable
 private fun WrappingContentLayout(
     block: WrappingContentBlock,
@@ -682,6 +734,7 @@ fun PaginatedReaderScreen(
     paragraphGapMultiplier: Float,
     imageSizeMultiplier: Float,
     horizontalMarginMultiplier: Float,
+    verticalMarginMultiplier: Float,
     fontFamily: FontFamily,
     textAlign: ReaderTextAlign,
     ttsHighlightInfo: TtsHighlightInfo?,
@@ -702,7 +755,8 @@ fun PaginatedReaderScreen(
     onHighlightDeleted: (String) -> Unit,
     activeHighlightPalette: List<HighlightColor>,
     onUpdatePalette: (Int, HighlightColor) -> Unit,
-    activeTextureId: String? = null
+    activeTextureId: String? = null,
+    activeTextureAlpha: Float = 0.55f
 ) {
     LaunchedEffect(userHighlights) {
         Timber.d("PaginatedReaderScreen: Received ${userHighlights.size} highlights.")
@@ -713,11 +767,7 @@ fun PaginatedReaderScreen(
 
     val context = LocalContext.current
     val textureBitmap = remember(activeTextureId) {
-        activeTextureId?.let { id ->
-            ReaderTexture.entries.find { it.id == id }?.resId?.let { resId ->
-                ImageBitmap.imageResource(context.resources, resId)
-            }
-        }
+        loadReaderTextureBitmap(context, activeTextureId)
     }
 
     val textureModifier = if (textureBitmap != null) {
@@ -725,13 +775,13 @@ fun PaginatedReaderScreen(
             val brush = ShaderBrush(
                 ImageShader(textureBitmap, TileMode.Repeated, TileMode.Repeated)
             )
-            drawRect(brush = brush, blendMode = BlendMode.Multiply, alpha = 0.6f)
+            drawRect(brush = brush, blendMode = BlendMode.SrcOver, alpha = activeTextureAlpha.coerceIn(0f, 1f))
         }
     } else Modifier
 
     var isNavigatingByLink by remember { mutableStateOf(false) }
 
-    BoxWithConstraints(modifier = modifier.fillMaxSize().background(effectiveBg).then(textureModifier)) {
+    BoxWithConstraints(modifier = modifier.fillMaxSize().background(effectiveBg)) {
         val textMeasurer = rememberTextMeasurer()
         val baseTextStyle = MaterialTheme.typography.bodyLarge
 
@@ -740,6 +790,7 @@ fun PaginatedReaderScreen(
         var debouncedParagraphGapMult by remember { mutableFloatStateOf(paragraphGapMultiplier) }
         var debouncedImageSizeMult by remember { mutableFloatStateOf(imageSizeMultiplier) }
         var debouncedHorizontalMarginMult by remember { mutableFloatStateOf(horizontalMarginMultiplier) }
+        var debouncedVerticalMarginMult by remember { mutableFloatStateOf(verticalMarginMultiplier) }
         var debouncedFontFamily by remember { mutableStateOf(fontFamily) }
         var debouncedTextAlign by remember { mutableStateOf(textAlign) }
 
@@ -781,7 +832,7 @@ fun PaginatedReaderScreen(
             debouncedFontFamily
         ) {
             val adjustedFontSize = baseTextStyle.fontSize * debouncedFontSizeMult
-            val adjustedLineHeight = adjustedFontSize * debouncedLineHeightMult
+            val adjustedLineHeight = adjustedFontSize * paginationLineHeightMultiplierForWebViewSetting(debouncedLineHeightMult)
 
             baseTextStyle.copy(
                 color = effectiveText,
@@ -810,12 +861,13 @@ fun PaginatedReaderScreen(
             }
         }
 
-        LaunchedEffect(fontSizeMultiplier, lineHeightMultiplier, paragraphGapMultiplier, imageSizeMultiplier, horizontalMarginMultiplier, fontFamily, textAlign) {
+        LaunchedEffect(fontSizeMultiplier, lineHeightMultiplier, paragraphGapMultiplier, imageSizeMultiplier, horizontalMarginMultiplier, verticalMarginMultiplier, fontFamily, textAlign) {
             if (fontSizeMultiplier != debouncedFontSizeMult ||
                 lineHeightMultiplier != debouncedLineHeightMult ||
                 paragraphGapMultiplier != debouncedParagraphGapMult ||
                 imageSizeMultiplier != debouncedImageSizeMult ||
                 horizontalMarginMultiplier != debouncedHorizontalMarginMult ||
+                verticalMarginMultiplier != debouncedVerticalMarginMult ||
                 fontFamily != debouncedFontFamily ||
                 textAlign != debouncedTextAlign
             ) {
@@ -836,6 +888,7 @@ fun PaginatedReaderScreen(
                 debouncedParagraphGapMult = paragraphGapMultiplier
                 debouncedImageSizeMult = imageSizeMultiplier
                 debouncedHorizontalMarginMult = horizontalMarginMultiplier
+                debouncedVerticalMarginMult = verticalMarginMultiplier
                 debouncedFontFamily = fontFamily
                 debouncedTextAlign = textAlign
                 Timber.d("Debounce complete. Applying new format settings.")
@@ -851,8 +904,28 @@ fun PaginatedReaderScreen(
         }
 
         val density = LocalDensity.current
-        val horizontalPadding = 16.dp * debouncedHorizontalMarginMult
-        val verticalPadding = 16.dp
+        val requestedHorizontalPadding = 16.dp * debouncedHorizontalMarginMult
+        val requestedVerticalPadding = 16.dp * debouncedVerticalMarginMult
+        val effectiveReaderPadding =
+            remember(this.constraints, density, requestedHorizontalPadding, requestedVerticalPadding) {
+                val requestedHorizontalPaddingPx = with(density) { requestedHorizontalPadding.roundToPx() }
+                val requestedVerticalPaddingPx = with(density) { requestedVerticalPadding.roundToPx() }
+                val minReadableWidthPx = with(density) { 96.dp.roundToPx() }
+                    .coerceAtMost(this.constraints.maxWidth)
+                val minReadableHeightPx = with(density) { 160.dp.roundToPx() }
+                    .coerceAtMost(this.constraints.maxHeight)
+                val horizontalPaddingPx = requestedHorizontalPaddingPx.coerceAtMost(
+                    ((this.constraints.maxWidth - minReadableWidthPx) / 2).coerceAtLeast(0)
+                )
+                val verticalPaddingPx = requestedVerticalPaddingPx.coerceAtMost(
+                    ((this.constraints.maxHeight - minReadableHeightPx) / 2).coerceAtLeast(0)
+                )
+                with(density) {
+                    horizontalPaddingPx.toDp() to verticalPaddingPx.toDp()
+                }
+            }
+        val horizontalPadding = effectiveReaderPadding.first
+        val verticalPadding = effectiveReaderPadding.second
 
         val textConstraints =
             remember(this.constraints, density, horizontalPadding, verticalPadding) {
@@ -860,9 +933,9 @@ fun PaginatedReaderScreen(
                 val verticalPaddingPx = with(density) { verticalPadding.roundToPx() }
                 val finalConstraints = this.constraints.copy(
                     minWidth = 0,
-                    maxWidth = this.constraints.maxWidth - (2 * horizontalPaddingPx),
+                    maxWidth = (this.constraints.maxWidth - (2 * horizontalPaddingPx)).coerceAtLeast(1),
                     minHeight = 0,
-                    maxHeight = this.constraints.maxHeight - (2 * verticalPaddingPx)
+                    maxHeight = (this.constraints.maxHeight - (2 * verticalPaddingPx)).coerceAtLeast(1)
                 )
                 finalConstraints
             }
@@ -950,7 +1023,8 @@ fun PaginatedReaderScreen(
                 mathMLRenderer = mathMLRenderer,
                 userTextAlign = userTextAlign,
                 paragraphGapMultiplier = debouncedParagraphGapMult,
-                imageSizeMultiplier = debouncedImageSizeMult
+                imageSizeMultiplier = debouncedImageSizeMult,
+                verticalMarginMultiplier = debouncedVerticalMarginMult
             )
         }
 
@@ -1168,7 +1242,10 @@ fun PaginatedReaderScreen(
             isDarkTheme = isDarkTheme,
             activeHighlightPalette = activeHighlightPalette,
             onUpdatePalette = onUpdatePalette,
-            effectiveText = effectiveText
+            effectiveText = effectiveText,
+            pageTextureModifier = if (isPageTurnAnimationEnabled) Modifier else textureModifier,
+            pageTextureBitmap = textureBitmap,
+            pageTextureAlpha = activeTextureAlpha.coerceIn(0f, 1f)
         )
 
         androidx.compose.animation.AnimatedVisibility(
@@ -1989,7 +2066,10 @@ internal fun PaginatedReaderContent(
     onHighlightDeleted: (String) -> Unit,
     activeHighlightPalette: List<HighlightColor>,
     onUpdatePalette: (Int, HighlightColor) -> Unit,
-    isDarkTheme: Boolean
+    isDarkTheme: Boolean,
+    pageTextureModifier: Modifier = Modifier,
+    pageTextureBitmap: ImageBitmap? = null,
+    pageTextureAlpha: Float = 0f
 ) {
     val coroutineScope = rememberCoroutineScope()
     val density = LocalDensity.current
@@ -2130,7 +2210,9 @@ internal fun PaginatedReaderContent(
                                 pageIndex,
                                 effectiveBg,
                                 isDarkTheme,
-                                pageTurnTouchY
+                                pageTurnTouchY,
+                                pageTextureBitmap,
+                                pageTextureAlpha
                             )
                         } else Modifier
 
@@ -2284,7 +2366,7 @@ internal fun PaginatedReaderContent(
                             pendingCrossPageSelection = null
                         }
 
-                        Box(modifier = Modifier.fillMaxSize().then(pageModifier)) {
+                        Box(modifier = Modifier.fillMaxSize().background(effectiveBg).then(pageTextureModifier).then(pageModifier)) {
                             Box(modifier = Modifier.fillMaxSize()) {
                                 Box(modifier = Modifier.fillMaxSize().pointerInput(Unit) {
                                     detectTapGestures(
@@ -2784,12 +2866,14 @@ internal fun PaginatedReaderContent(
                                                                 val markerAreaModifier =
                                                                     Modifier.width(32.dp)
                                                                         .padding(end = 8.dp)
+                                                                val itemMarkerImage = block.itemMarkerImage
+                                                                val itemMarker = block.itemMarker
 
-                                                                if (block.itemMarkerImage != null) {
+                                                                if (itemMarkerImage != null) {
                                                                     val imageRequest =
                                                                         Builder(LocalContext.current).data(
                                                                             File(
-                                                                                block.itemMarkerImage
+                                                                                itemMarkerImage
                                                                             )
                                                                         ).crossfade(true).build()
                                                                     val imageSize = with(density) {
@@ -2805,9 +2889,9 @@ internal fun PaginatedReaderContent(
                                                                         alignment = Alignment.CenterEnd,
                                                                         contentScale = ContentScale.FillHeight
                                                                     )
-                                                                } else if (block.itemMarker != null) {
+                                                                } else if (itemMarker != null) {
                                                                     Text(
-                                                                        text = block.itemMarker,
+                                                                        text = itemMarker,
                                                                         style = textStyle.copy(
                                                                             textAlign = TextAlign.End
                                                                         ),
@@ -3017,10 +3101,12 @@ internal fun PaginatedReaderContent(
                                                         }
 
                                                         is MathBlock -> {
+                                                            val svgContent = block.svgContent?.takeIf { it.isNotBlank() }
                                                             Timber.d(
-                                                                "PaginatedReader: Rendering MathBlock. Alt: '${block.altText}', Has SVG: ${!block.svgContent.isNullOrBlank()}"
+                                                                "PaginatedReader: Rendering MathBlock. Alt: '${block.altText}', Has SVG: ${svgContent != null}"
                                                             )
-                                                            if (!block.svgContent.isNullOrBlank()) {
+                                                            if (svgContent != null) {
+                                                                val nonBlankSvgContent = svgContent
                                                                 BoxWithConstraints(
                                                                     modifier = paddingModifier
                                                                 ) {
@@ -3104,7 +3190,7 @@ internal fun PaginatedReaderContent(
                                                                     val imageRequest =
                                                                         Builder(LocalContext.current).data(
                                                                             SvgData(
-                                                                                block.svgContent
+                                                                                nonBlankSvgContent
                                                                             )
                                                                         ).listener(
                                                                             onError = { _, result ->
@@ -3189,7 +3275,10 @@ internal fun PaginatedReaderContent(
                                                                         )
                                                                     }).crossfade(true).build()
 
-                                                            BoxWithConstraints(modifier = paddingModifier) {
+                                                            BoxWithConstraints(
+                                                                modifier = paddingModifier,
+                                                                contentAlignment = imageBlockContentAlignment(style)
+                                                            ) {
                                                                 val scaledSize = computeImageRenderSizeDp(
                                                                     block = block,
                                                                     density = density,
@@ -3357,9 +3446,10 @@ internal fun PaginatedReaderContent(
                                                                                             Row(
                                                                                                 verticalAlignment = Alignment.Top
                                                                                             ) {
-                                                                                                if (blockInCell.itemMarker != null) {
+                                                                                                val itemMarker = blockInCell.itemMarker
+                                                                                                if (itemMarker != null) {
                                                                                                     Text(
-                                                                                                        text = blockInCell.itemMarker,
+                                                                                                        text = itemMarker,
                                                                                                         style = cellTextStyle,
                                                                                                         modifier = Modifier.padding(
                                                                                                             end = 4.dp
@@ -3390,40 +3480,23 @@ internal fun PaginatedReaderContent(
                                                                                         }
 
                                                                                         is ImageBlock -> {
-                                                                                            BoxWithConstraints(modifier = Modifier.fillMaxWidth()) {
-                                                                                                val scaledSize = computeImageRenderSizeDp(
+                                                                                            AsyncImage(
+                                                                                                model = Builder(
+                                                                                                    LocalContext.current
+                                                                                                ).data(
+                                                                                                    File(
+                                                                                                        blockInCell.path
+                                                                                                    )
+                                                                                                )
+                                                                                                    .build(),
+                                                                                                contentDescription = blockInCell.altText,
+                                                                                                contentScale = ContentScale.Fit,
+                                                                                                modifier = tableCellImageModifier(
                                                                                                     block = blockInCell,
                                                                                                     density = density,
-                                                                                                    maxWidthDp = maxWidth,
                                                                                                     imageSizeMultiplier = imageSizeMultiplier
                                                                                                 )
-                                                                                                val imageModifier = Modifier.then(
-                                                                                                    if (scaledSize != null) {
-                                                                                                        Modifier.width(scaledSize.first).height(scaledSize.second)
-                                                                                                    } else {
-                                                                                                        Modifier.fillMaxWidth().then(
-                                                                                                            if (blockInCell.expectedHeight > 0) {
-                                                                                                                Modifier.height(with(density) { (blockInCell.expectedHeight * imageSizeMultiplier).toDp() })
-                                                                                                            } else {
-                                                                                                                Modifier.height(250.dp)
-                                                                                                            }
-                                                                                                        )
-                                                                                                    }
-                                                                                                )
-                                                                                                AsyncImage(
-                                                                                                    model = Builder(
-                                                                                                        LocalContext.current
-                                                                                                    ).data(
-                                                                                                        File(
-                                                                                                            blockInCell.path
-                                                                                                        )
-                                                                                                    )
-                                                                                                        .build(),
-                                                                                                    contentDescription = blockInCell.altText,
-                                                                                                    contentScale = ContentScale.Fit,
-                                                                                                    modifier = imageModifier
-                                                                                                )
-                                                                                            }
+                                                                                            )
                                                                                         }
 
                                                                                         is TextContentBlock -> {
@@ -4101,10 +4174,12 @@ private fun RenderFlexChildBlock(
                 val markerAreaModifier = Modifier
                     .width(32.dp)
                     .padding(end = 8.dp)
+                val itemMarkerImage = childBlock.itemMarkerImage
+                val itemMarker = childBlock.itemMarker
 
-                if (childBlock.itemMarkerImage != null) {
+                if (itemMarkerImage != null) {
                     val imageRequest =
-                        Builder(LocalContext.current).data(File(childBlock.itemMarkerImage))
+                        Builder(LocalContext.current).data(File(itemMarkerImage))
                             .crossfade(true).build()
                     val imageSize = with(density) { (textStyle.fontSize.value * 0.8f).sp.toDp() }
 
@@ -4115,9 +4190,9 @@ private fun RenderFlexChildBlock(
                         alignment = Alignment.CenterEnd,
                         contentScale = ContentScale.FillHeight
                     )
-                } else if (childBlock.itemMarker != null) {
+                } else if (itemMarker != null) {
                     Text(
-                        text = childBlock.itemMarker,
+                        text = itemMarker,
                         style = textStyle.copy(textAlign = TextAlign.End),
                         modifier = markerAreaModifier
                     )
@@ -4160,7 +4235,7 @@ private fun RenderFlexChildBlock(
                 ColorFilter.colorMatrix(ColorMatrix(matrix))
             } else null
 
-            BoxWithConstraints {
+            BoxWithConstraints(contentAlignment = imageBlockContentAlignment(style)) {
                 val scaledSize = computeImageRenderSizeDp(
                     block = childBlock,
                     density = density,
@@ -4278,37 +4353,20 @@ private fun RenderFlexChildBlock(
                                             modifier = Modifier.fillMaxWidth()
                                         )
                                     } else if (blockInCell is ImageBlock) {
-                                        BoxWithConstraints(modifier = Modifier.fillMaxWidth()) {
-                                            val scaledSize = computeImageRenderSizeDp(
+                                        AsyncImage(
+                                            model = Builder(LocalContext.current).data(
+                                                File(
+                                                    blockInCell.path
+                                                )
+                                            ).build(),
+                                            contentDescription = blockInCell.altText,
+                                            contentScale = ContentScale.Fit,
+                                            modifier = tableCellImageModifier(
                                                 block = blockInCell,
                                                 density = density,
-                                                maxWidthDp = maxWidth,
                                                 imageSizeMultiplier = imageSizeMultiplier
                                             )
-                                            val imageModifier = Modifier.then(
-                                                if (scaledSize != null) {
-                                                    Modifier.width(scaledSize.first).height(scaledSize.second)
-                                                } else {
-                                                    Modifier.fillMaxWidth().then(
-                                                        if (blockInCell.expectedHeight > 0) {
-                                                            Modifier.height(with(density) { (blockInCell.expectedHeight * imageSizeMultiplier).toDp() })
-                                                        } else {
-                                                            Modifier.height(250.dp)
-                                                        }
-                                                    )
-                                                }
-                                            )
-                                            AsyncImage(
-                                                model = Builder(LocalContext.current).data(
-                                                    File(
-                                                        blockInCell.path
-                                                    )
-                                                ).build(),
-                                                contentDescription = blockInCell.altText,
-                                                contentScale = ContentScale.Fit,
-                                                modifier = imageModifier
-                                            )
-                                        }
+                                        )
                                     }
                                 }
                             }
@@ -4332,7 +4390,9 @@ private fun Modifier.realisticBookPage(
     pageIndex: Int,
     paperColor: Color,
     isDarkTheme: Boolean,
-    touchY: Float?
+    touchY: Float?,
+    textureBitmap: ImageBitmap? = null,
+    textureAlpha: Float = 0f
 ): Modifier = composed {
 
     val frontPath = remember { Path() }
@@ -4360,9 +4420,19 @@ private fun Modifier.realisticBookPage(
         .drawWithContent {
             val drawStart = System.nanoTime()
             val pageOffset = (pageIndex - pagerState.currentPage) - pagerState.currentPageOffsetFraction
+            fun drawPaperBackground() {
+                drawRect(color = paperColor)
+                if (textureBitmap != null && textureAlpha > 0f) {
+                    drawRect(
+                        brush = ShaderBrush(ImageShader(textureBitmap, TileMode.Repeated, TileMode.Repeated)),
+                        blendMode = BlendMode.SrcOver,
+                        alpha = textureAlpha
+                    )
+                }
+            }
 
             if (abs(pageOffset) < 0.001f) {
-                drawRect(color = paperColor)
+                drawPaperBackground()
                 drawContent()
             }
             else if (pageOffset < 0f && pageOffset > -1f) {
@@ -4423,7 +4493,7 @@ private fun Modifier.realisticBookPage(
                     frontPath.close()
 
                     clipPath(frontPath) {
-                        drawRect(color = paperColor)
+                        drawPaperBackground()
                         this@drawWithContent.drawContent()
                     }
 
@@ -4466,6 +4536,15 @@ private fun Modifier.realisticBookPage(
                     clipRect(0f, 0f, w, h) {
                         clipPath(frontPath) {
                             drawPath(reflectedScreenPath, color = paperColor)
+                            if (textureBitmap != null && textureAlpha > 0f) {
+                                clipPath(reflectedScreenPath) {
+                                    drawRect(
+                                        brush = ShaderBrush(ImageShader(textureBitmap, TileMode.Repeated, TileMode.Repeated)),
+                                        blendMode = BlendMode.SrcOver,
+                                        alpha = textureAlpha
+                                    )
+                                }
+                            }
                             val flapTint = if (isDarkTheme) Color.White.copy(alpha = 0.08f) else Color.Black.copy(alpha = 0.06f)
                             drawPath(reflectedScreenPath, color = flapTint)
 
@@ -4493,12 +4572,12 @@ private fun Modifier.realisticBookPage(
                     }
 
                 } else {
-                    drawRect(color = paperColor)
+                    drawPaperBackground()
                     drawContent()
                 }
             }
             else {
-                drawRect(color = paperColor)
+                drawPaperBackground()
                 drawContent()
             }
 
@@ -4515,10 +4594,14 @@ fun Modifier.drawCssBorders(
     blockStyle: BlockStyle,
     @Suppress("unused") density: Density
 ): Modifier = this.drawBehind {
-    val topWidth = blockStyle.borderTop?.width?.toPx() ?: 0f
-    val rightWidth = blockStyle.borderRight?.width?.toPx() ?: 0f
-    val bottomWidth = blockStyle.borderBottom?.width?.toPx() ?: 0f
-    val leftWidth = blockStyle.borderLeft?.width?.toPx() ?: 0f
+    val borderTop = blockStyle.borderTop
+    val borderRight = blockStyle.borderRight
+    val borderBottom = blockStyle.borderBottom
+    val borderLeft = blockStyle.borderLeft
+    val topWidth = borderTop?.width?.toPx() ?: 0f
+    val rightWidth = borderRight?.width?.toPx() ?: 0f
+    val bottomWidth = borderBottom?.width?.toPx() ?: 0f
+    val leftWidth = borderLeft?.width?.toPx() ?: 0f
 
     val tlRadius = blockStyle.borderTopLeftRadius.toPx()
     val trRadius = blockStyle.borderTopRightRadius.toPx()
@@ -4550,9 +4633,9 @@ fun Modifier.drawCssBorders(
     }
 
     // TOP
-    if (topWidth > 0f && blockStyle.borderTop != null) {
-        val color = blockStyle.borderTop.color
-        val effect = getPathEffect(blockStyle.borderTop.style, topWidth)
+    if (topWidth > 0f && borderTop != null) {
+        val color = borderTop.color
+        val effect = getPathEffect(borderTop.style, topWidth)
         val offset = topWidth / 2f
 
         val startX = if (tlRadius > 0) tlRadius else 0f
@@ -4568,9 +4651,9 @@ fun Modifier.drawCssBorders(
     }
 
     // BOTTOM
-    if (bottomWidth > 0f && blockStyle.borderBottom != null) {
-        val color = blockStyle.borderBottom.color
-        val effect = getPathEffect(blockStyle.borderBottom.style, bottomWidth)
+    if (bottomWidth > 0f && borderBottom != null) {
+        val color = borderBottom.color
+        val effect = getPathEffect(borderBottom.style, bottomWidth)
         val offset = size.height - (bottomWidth / 2f)
 
         val startX = if (blRadius > 0) blRadius else 0f
@@ -4586,9 +4669,9 @@ fun Modifier.drawCssBorders(
     }
 
     // LEFT
-    if (leftWidth > 0f && blockStyle.borderLeft != null) {
-        val color = blockStyle.borderLeft.color
-        val effect = getPathEffect(blockStyle.borderLeft.style, leftWidth)
+    if (leftWidth > 0f && borderLeft != null) {
+        val color = borderLeft.color
+        val effect = getPathEffect(borderLeft.style, leftWidth)
         val offset = leftWidth / 2f
 
         val startY = if (tlRadius > 0) tlRadius else 0f
@@ -4604,9 +4687,9 @@ fun Modifier.drawCssBorders(
     }
 
     // RIGHT
-    if (rightWidth > 0f && blockStyle.borderRight != null) {
-        val color = blockStyle.borderRight.color
-        val effect = getPathEffect(blockStyle.borderRight.style, rightWidth)
+    if (rightWidth > 0f && borderRight != null) {
+        val color = borderRight.color
+        val effect = getPathEffect(borderRight.style, rightWidth)
         val offset = size.width - (rightWidth / 2f)
 
         val startY = if (trRadius > 0) trRadius else 0f
@@ -4621,9 +4704,9 @@ fun Modifier.drawCssBorders(
         )
     }
 
-    if (tlRadius > 0f && topWidth > 0f && leftWidth > 0f && blockStyle.borderTop != null) {
+    if (tlRadius > 0f && topWidth > 0f && leftWidth > 0f && borderTop != null) {
         drawArc(
-            color = blockStyle.borderTop.color,
+            color = borderTop.color,
             startAngle = 180f, sweepAngle = 90f,
             useCenter = false,
             topLeft = Offset(leftWidth/2f, topWidth/2f),
@@ -4632,9 +4715,9 @@ fun Modifier.drawCssBorders(
         )
     }
 
-    if (trRadius > 0f && topWidth > 0f && rightWidth > 0f && blockStyle.borderTop != null) {
+    if (trRadius > 0f && topWidth > 0f && rightWidth > 0f && borderTop != null) {
         drawArc(
-            color = blockStyle.borderTop.color,
+            color = borderTop.color,
             startAngle = 270f, sweepAngle = 90f,
             useCenter = false,
             topLeft = Offset(size.width - (trRadius * 2) + (rightWidth/2f), topWidth/2f),
@@ -4643,9 +4726,9 @@ fun Modifier.drawCssBorders(
         )
     }
 
-    if (brRadius > 0f && bottomWidth > 0f && rightWidth > 0f && blockStyle.borderBottom != null) {
+    if (brRadius > 0f && bottomWidth > 0f && rightWidth > 0f && borderBottom != null) {
         drawArc(
-            color = blockStyle.borderBottom.color,
+            color = borderBottom.color,
             startAngle = 0f, sweepAngle = 90f,
             useCenter = false,
             topLeft = Offset(size.width - (brRadius * 2) + (rightWidth/2f), size.height - (brRadius * 2) + (bottomWidth/2f)),
@@ -4654,9 +4737,9 @@ fun Modifier.drawCssBorders(
         )
     }
 
-    if (blRadius > 0f && bottomWidth > 0f && leftWidth > 0f && blockStyle.borderBottom != null) {
+    if (blRadius > 0f && bottomWidth > 0f && leftWidth > 0f && borderBottom != null) {
         drawArc(
-            color = blockStyle.borderBottom.color,
+            color = borderBottom.color,
             startAngle = 90f, sweepAngle = 90f,
             useCenter = false,
             topLeft = Offset(leftWidth/2f, size.height - (blRadius * 2) + (bottomWidth/2f)),

app/src/main/java/com/aryan/reader/paginatedreader/PaginatedReaderViewModel.kt

@@ -145,7 +145,8 @@ class PaginatedReaderViewModel : ViewModel() {
                 mathMLRenderer = mathMLRenderer,
                 userTextAlign = null,
                 paragraphGapMultiplier = paragraphGapMultiplier,
-                imageSizeMultiplier = 1.0f
+                imageSizeMultiplier = 1.0f,
+                verticalMarginMultiplier = 1.0f
             )
             paginator = newPaginator
 

app/src/main/java/com/aryan/reader/paginatedreader/data/BookCacheDatabase.kt

@@ -198,7 +198,7 @@ abstract class BookCacheDao {
         ConfigurationCache::class,
         AnchorIndexEntry::class
     ],
-    version = 8,
+    version = 10,
     exportSchema = false
 )
 abstract class BookCacheDatabase : RoomDatabase() {

app/src/main/java/com/aryan/reader/paginatedreader/data/BookCacheEntities.kt

@@ -25,7 +25,7 @@ import androidx.room.ForeignKey
 import androidx.room.Index
 import androidx.room.PrimaryKey
 
-const val LATEST_PROCESSING_VERSION = 8
+const val LATEST_PROCESSING_VERSION = 10
 
 @Entity(tableName = "processed_books")
 data class ProcessedBook(

app/src/main/java/com/aryan/reader/paginatedreader/data/BookProcessingWorker.kt

@@ -39,7 +39,7 @@ import com.aryan.reader.paginatedreader.FontFaceInfo
 import com.aryan.reader.paginatedreader.MathMLRenderer
 import com.aryan.reader.paginatedreader.OptimizedCssRules
 import com.aryan.reader.paginatedreader.RenderResult
-import com.aryan.reader.paginatedreader.htmlToSemanticBlocks
+import com.aryan.reader.paginatedreader.androidHtmlToSemanticBlocks
 import com.aryan.reader.paginatedreader.loadFontFamilies
 import com.aryan.reader.paginatedreader.semanticBlockModule
 import kotlinx.coroutines.Dispatchers
@@ -277,7 +277,7 @@ class BookProcessingWorker(
                             Timber.d("Chapter $index (Background Worker): Processed HTML contains <math-placeholder>: ${processedHtml.contains("math-placeholder")}")
 
 
-                            val semanticBlocks = htmlToSemanticBlocks(
+                            val semanticBlocks = androidHtmlToSemanticBlocks(
                                 html = processedHtml,
                                 cssRules = lightThemeCssRules,
                                 textStyle = textStyle,

app/src/main/java/com/aryan/reader/pdf/MagnifierComposable.kt

@@ -40,6 +40,7 @@ import androidx.compose.ui.unit.Dp
 import androidx.compose.ui.unit.IntOffset
 import androidx.compose.ui.unit.IntSize
 import androidx.compose.ui.unit.dp
+import kotlin.math.max
 import kotlin.math.roundToInt
 
 @Composable
@@ -68,6 +69,9 @@ fun MagnifierComposable(
         Canvas(modifier = Modifier.fillMaxSize()) {
             val magnifierWidthPx = size.width
             val magnifierHeightPx = size.height
+            if (magnifierWidthPx <= 0f || magnifierHeightPx <= 0f || zoomFactor <= 0f) {
+                return@Canvas
+            }
 
             Timber.d("Magnifier: START. scale=$currentScale, centerOnBitmap=$magnifierCenterOnBitmap")
 
@@ -109,8 +113,10 @@ fun MagnifierComposable(
                 val srcTop = (centerInTileBitmap.y - sourceRectHeight / 2f)
                 Timber.d("Magnifier: Calculated source top-left=($srcLeft, $srcTop)")
 
-                val clampedSrcLeft = srcLeft.coerceIn(0f, bitmapToUse.width.toFloat() - sourceRectWidth.coerceAtLeast(1f))
-                val clampedSrcTop = srcTop.coerceIn(0f, bitmapToUse.height.toFloat() - sourceRectHeight.coerceAtLeast(1f))
+                val maxSrcLeft = max(0f, bitmapToUse.width.toFloat() - sourceRectWidth.coerceAtLeast(1f))
+                val maxSrcTop = max(0f, bitmapToUse.height.toFloat() - sourceRectHeight.coerceAtLeast(1f))
+                val clampedSrcLeft = srcLeft.coerceIn(0f, maxSrcLeft)
+                val clampedSrcTop = srcTop.coerceIn(0f, maxSrcTop)
                 Timber.d("Magnifier: Clamped source top-left=($clampedSrcLeft, $clampedSrcTop)")
 
                 val finalSrcLeftInt = clampedSrcLeft.roundToInt()
@@ -174,8 +180,10 @@ fun MagnifierComposable(
                 val srcTop = (magnifierCenterOnBitmap.y - sourceRectHeight / 2f)
                 Timber.d("Magnifier: Calculated source top-left=($srcLeft, $srcTop)")
 
-                val clampedSrcLeft = srcLeft.coerceIn(0f, sourceBitmap.width.toFloat() - sourceRectWidth.coerceAtLeast(1f))
-                val clampedSrcTop = srcTop.coerceIn(0f, sourceBitmap.height.toFloat() - sourceRectHeight.coerceAtLeast(1f))
+                val maxSrcLeft = max(0f, sourceBitmap.width.toFloat() - sourceRectWidth.coerceAtLeast(1f))
+                val maxSrcTop = max(0f, sourceBitmap.height.toFloat() - sourceRectHeight.coerceAtLeast(1f))
+                val clampedSrcLeft = srcLeft.coerceIn(0f, maxSrcLeft)
+                val clampedSrcTop = srcTop.coerceIn(0f, maxSrcTop)
                 Timber.d("Magnifier: Clamped source top-left=($clampedSrcLeft, $clampedSrcTop)")
 
                 val finalSrcLeftInt = clampedSrcLeft.roundToInt()

app/src/main/java/com/aryan/reader/pdf/NativePdfiumBridge.kt

@@ -1,5 +1,7 @@
 package com.aryan.reader.pdf
 
+import com.aryan.reader.shared.pdf.PdfiumAnnotationSubtype
+
 object NativePdfiumBridge {
     init {
         System.loadLibrary("native-lib")
@@ -31,9 +33,9 @@ object NativePdfiumBridge {
     @JvmStatic external fun getAnnotRectAtPoint(pagePtr: Long, x: Double, y: Double): FloatArray?
     @JvmStatic external fun checkActionSupport(): Boolean
 
-    const val ANNOT_TEXT = 1         // Sticky Note
-    const val ANNOT_LINK = 2         // Link
-    const val ANNOT_HIGHLIGHT = 8    // Highlight
-    const val ANNOT_INK = 12         // Freehand drawing
-    const val ANNOT_WIDGET = 19
+    const val ANNOT_TEXT = PdfiumAnnotationSubtype.TEXT
+    const val ANNOT_LINK = PdfiumAnnotationSubtype.LINK
+    const val ANNOT_HIGHLIGHT = PdfiumAnnotationSubtype.HIGHLIGHT
+    const val ANNOT_INK = PdfiumAnnotationSubtype.INK
+    const val ANNOT_WIDGET = PdfiumAnnotationSubtype.WIDGET
 }

app/src/main/java/com/aryan/reader/pdf/PdfNavigationUI.kt

@@ -84,7 +84,9 @@ fun VerticalScrollbar(
 
             if (viewportRatio >= 1f) return@derivedStateOf null
 
-            val thumbHeight = (viewportHeight * viewportRatio).coerceIn(80f, viewportHeight / 2)
+            val maxThumbHeight = viewportHeight / 2f
+            val minThumbHeight = minOf(80f, maxThumbHeight)
+            val thumbHeight = (viewportHeight * viewportRatio).coerceIn(minThumbHeight, maxThumbHeight)
 
             val firstItemIndex = listState.firstVisibleItemIndex
             val firstItemOffset = listState.firstVisibleItemScrollOffset

app/src/main/java/com/aryan/reader/pdf/PdfPageComposable.kt

@@ -69,9 +69,13 @@ import androidx.compose.ui.graphics.BlendMode
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.ColorFilter
 import androidx.compose.ui.graphics.ColorMatrix
+import androidx.compose.ui.graphics.ImageBitmap
+import androidx.compose.ui.graphics.ImageShader
 import androidx.compose.ui.graphics.Path
+import androidx.compose.ui.graphics.ShaderBrush
 import androidx.compose.ui.graphics.StrokeCap
 import androidx.compose.ui.graphics.StrokeJoin
+import androidx.compose.ui.graphics.TileMode
 import androidx.compose.ui.graphics.asImageBitmap
 import androidx.compose.ui.graphics.drawscope.Stroke
 import androidx.compose.ui.graphics.drawscope.clipRect
@@ -119,6 +123,7 @@ import androidx.core.graphics.scale
 import androidx.core.graphics.set
 import com.aryan.reader.R
 import com.aryan.reader.SearchResult
+import com.aryan.reader.loadReaderTextureBitmap
 import com.aryan.reader.ml.SpeechBubble
 import com.aryan.reader.pdf.data.PdfAnnotation
 import com.aryan.reader.pdf.data.PdfTextBox
@@ -127,6 +132,7 @@ import com.aryan.reader.pdf.ocr.OcrElement
 import com.aryan.reader.pdf.ocr.OcrResult
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.FlowPreview
+import kotlinx.coroutines.Job
 import kotlinx.coroutines.NonCancellable
 import kotlinx.coroutines.channels.Channel
 import kotlinx.coroutines.coroutineScope
@@ -180,6 +186,13 @@ data class PdfPoint(val x: Float, val y: Float, val timestamp: Long = 0L)
 
 data class PdfTile(val bitmap: Bitmap, val renderRect: Rect, val tileId: Int, val renderScale: Float = 1f)
 
+private const val PDF_TILE_SIZE_DP = 256
+private const val PDF_MAX_TILE_BITMAP_SIZE_PX = 3072
+private const val PDF_TILE_SCALE_TOLERANCE = 0.06f
+private const val PDF_TILE_IDLE_RENDER_DELAY_MS = 90L
+private const val PDF_PAGINATION_PAN_FLING_MIN_VELOCITY = 600f
+private const val PDF_PAGINATION_PAN_FLING_MULTIPLIER = 0.72f
+
 enum class LinkSource {
     ANNOTATION, TEXT_CONTENT
 }
@@ -426,7 +439,10 @@ data class PageStaticData(
     val colorFilter: StableHolder<ColorFilter?>,
     val isDarkMode: Boolean,
     val excludeImages: Boolean,
-    val imageRects: StableHolder<List<android.graphics.Rect>>
+    val imageRects: StableHolder<List<android.graphics.Rect>>,
+    val textureBitmap: StableHolder<ImageBitmap?>,
+    val textureAlpha: Float,
+    val textureBlendMode: BlendMode
 )
 
 @Stable
@@ -497,6 +513,7 @@ internal fun PdfPageComposable(
     onTtsHighlightCenterCalculated: ((Float) -> Unit)? = null,
     onSearchHighlightCenterCalculated: ((Float) -> Unit)? = null,
     activeTheme: com.aryan.reader.ReaderTheme = com.aryan.reader.ReaderTheme("no_theme", "No Theme", Color.Unspecified, Color.Unspecified, false),
+    activeTextureAlpha: Float = 0.55f,
     excludeImages: Boolean = false,
     onDoubleTap: ((Offset) -> Unit)? = null,
     isEditMode: Boolean = false,
@@ -552,7 +569,7 @@ internal fun PdfPageComposable(
     var isLoadingPage by remember { mutableStateOf(true) }
     var pageErrorMessage by remember { mutableStateOf<String?>(null) }
     val density = LocalDensity.current
-    LocalContext.current
+    val context = LocalContext.current
     val viewConfiguration = LocalViewConfiguration.current
     val coroutineScope = rememberCoroutineScope()
     var isStylusEraserOverride by remember { mutableStateOf(false) }
@@ -564,6 +581,7 @@ internal fun PdfPageComposable(
     var isTransforming by remember { mutableStateOf(false) }
     var scale by remember { mutableFloatStateOf(1f) }
     var offset by remember { mutableStateOf(Offset.Zero) }
+    var paginationPanFlingJob by remember { mutableStateOf<Job?>(null) }
 
     LaunchedEffect(scale, offset) {
         onZoomAndPanChanged?.invoke(scale, offset)
@@ -590,8 +608,10 @@ internal fun PdfPageComposable(
     val pdfPageIndex = (virtualPage as? VirtualPage.PdfPage)?.pdfIndex ?: pageIndex
 
     var tiles by remember { mutableStateOf<List<PdfTile>>(emptyList()) }
-    val tileSizeDp = 256.dp
+    val tileSizeDp = PDF_TILE_SIZE_DP.dp
     val tileSizePx = with(LocalDensity.current) { tileSizeDp.toPx().toInt() }
+    val latestEffectiveScale by rememberUpdatedState(effectiveScale)
+    val latestEffectiveOffset by rememberUpdatedState(effectiveOffset)
 
     SideEffect {
         Timber.tag("PdfDrawPerf")
@@ -633,6 +653,8 @@ internal fun PdfPageComposable(
     var actualBitmapHeightPx by remember { mutableIntStateOf(0) }
     var currentPageRotation by remember { mutableIntStateOf(0) }
 
+    val needsTilingNow = (effectiveScale > 1f || actualBitmapWidthPx > 3000 || actualBitmapHeightPx > 3000) && (isVerticalScroll || isActivePage)
+
     val canvasWidthPx = remember { mutableFloatStateOf(0f) }
     val canvasHeightPx = remember { mutableFloatStateOf(0f) }
 
@@ -687,6 +709,15 @@ internal fun PdfPageComposable(
             activeTheme.backgroundColor
         }
     }
+    val textureBitmap = remember(activeTheme.textureId) {
+        loadReaderTextureBitmap(context, activeTheme.textureId)
+    }
+    val effectiveTextureAlpha = remember(activeTheme.textureId, activeTextureAlpha) {
+        if (activeTheme.textureId == null) 0f else activeTextureAlpha.coerceIn(0f, 1f)
+    }
+    val textureBlendMode = remember(activeTheme.textureId, activeTheme.isDark, activeTheme.id) {
+        if (activeTheme.isDark || activeTheme.id == "reverse") BlendMode.Screen else BlendMode.Multiply
+    }
 
     val centeringOffsetX by remember(canvasWidthPx.floatValue, actualBitmapWidthPx) {
         derivedStateOf { (canvasWidthPx.floatValue - actualBitmapWidthPx) / 2f }
@@ -1146,13 +1177,13 @@ internal fun PdfPageComposable(
                     try {
                         val pagePtr = pageWrapper.getNativePointer()
                         if (pagePtr != 0L) {
-                            val objCount = NativePdfiumBridge.getPageObjectCount(pagePtr)
+                            val objCount = PdfiumEngineProvider.bridge.getPageObjectCount(pagePtr)
                             val imgRects = mutableListOf<android.graphics.Rect>()
                             val outRect = FloatArray(4)
 
                             for (i in 0 until objCount) {
-                                if (NativePdfiumBridge.getPageObjectType(pagePtr, i) == 3) { // 3 = FPDF_PAGEOBJ_IMAGE
-                                    if (NativePdfiumBridge.getPageObjectBoundingBox(pagePtr, i, outRect)) {
+                                if (PdfiumEngineProvider.bridge.getPageObjectType(pagePtr, i) == 3) { // 3 = FPDF_PAGEOBJ_IMAGE
+                                    if (PdfiumEngineProvider.bridge.getPageObjectBoundingBox(pagePtr, i, outRect)) {
                                         val pdfRectF = android.graphics.RectF(
                                             min(outRect[0], outRect[2]),
                                             max(outRect[1], outRect[3]),
@@ -1180,26 +1211,26 @@ internal fun PdfPageComposable(
                         val pagePtr = pageWrapper.getNativePointer()
 
                         if (pagePtr != 0L) {
-                            val count = NativePdfiumBridge.getAnnotCount(pagePtr)
+                            val count = PdfiumEngineProvider.bridge.getAnnotCount(pagePtr)
                             Timber.tag("PdfCommentDebug").d("Page $pageIndex: Total Annotations found = $count")
                             if (count > 0) {
-                                val count = NativePdfiumBridge.getAnnotCount(pagePtr)
+                                val count = PdfiumEngineProvider.bridge.getAnnotCount(pagePtr)
                                 Timber.tag("PdfCommentDebug").d("Page $pageIndex: Total Annotations found = $count")
                                 if (count > 0) {
                                     val allAnnots = (0 until count).mapNotNull { i ->
-                                        val subtype = NativePdfiumBridge.getAnnotSubtype(pagePtr, i)
+                                        val subtype = PdfiumEngineProvider.bridge.getAnnotSubtype(pagePtr, i)
                                         if (subtype == annotLink) return@mapNotNull null
 
-                                        var contents = NativePdfiumBridge.getAnnotString(pagePtr, i, "Contents")
+                                        var contents = PdfiumEngineProvider.bridge.getAnnotString(pagePtr, i, "Contents")
                                         if (contents.isNullOrBlank()) {
-                                            contents = NativePdfiumBridge.getAnnotString(pagePtr, i, "RC")
+                                            contents = PdfiumEngineProvider.bridge.getAnnotString(pagePtr, i, "RC")
                                         }
 
-                                        val name = NativePdfiumBridge.getAnnotString(pagePtr, i, "NM")
-                                        val irt = NativePdfiumBridge.getAnnotString(pagePtr, i, "IRT")
-                                        val author = NativePdfiumBridge.getAnnotString(pagePtr, i, "T")
+                                        val name = PdfiumEngineProvider.bridge.getAnnotString(pagePtr, i, "NM")
+                                        val irt = PdfiumEngineProvider.bridge.getAnnotString(pagePtr, i, "IRT")
+                                        val author = PdfiumEngineProvider.bridge.getAnnotString(pagePtr, i, "T")
 
-                                        val pdfRectArray = NativePdfiumBridge.getAnnotRect(pagePtr, i)
+                                        val pdfRectArray = PdfiumEngineProvider.bridge.getAnnotRect(pagePtr, i)
                                         val pdfRectF = if (pdfRectArray != null) {
                                             android.graphics.RectF(
                                                 min(pdfRectArray[0], pdfRectArray[2]),
@@ -1311,8 +1342,7 @@ internal fun PdfPageComposable(
     }
 
     LaunchedEffect(
-        effectiveScale,
-        effectiveOffset,
+        needsTilingNow,
         actualBitmapWidthPx,
         actualBitmapHeightPx,
         canvasWidthPx.floatValue,
@@ -1323,8 +1353,7 @@ internal fun PdfPageComposable(
         virtualPage,
         isActivePage
     ) {
-        val needsTiling = (effectiveScale > 1f || actualBitmapWidthPx > 3000 || actualBitmapHeightPx > 3000) && (isVerticalScroll || isActivePage)
-        if (!needsTiling) {
+        if (!needsTilingNow) {
             if (tiles.isNotEmpty()) {
                 val oldTiles = tiles
                 tiles = emptyList()
@@ -1358,24 +1387,37 @@ internal fun PdfPageComposable(
 
             snapshotFlow {
                 val rect = visibleScreenRect()
-                if (rect == null) null
-                else {
+                val observedScale = latestEffectiveScale
+                if (isVerticalScroll && rect != null) {
                     val qTop = rect.top / (tileSizePx / 2)
                     val qLeft = rect.left / (tileSizePx / 2)
                     val qBottom = rect.bottom / (tileSizePx / 2)
                     val qRight = rect.right / (tileSizePx / 2)
-                    listOf(qTop, qLeft, qBottom, qRight)
+                    listOf(qTop, qLeft, qBottom, qRight, (observedScale * 10f).roundToInt())
+                } else if (!isVerticalScroll) {
+                    val observedOffset = latestEffectiveOffset
+                    val pivotX = screenWidth / 2f
+                    val pivotY = screenHeight / 2f
+                    val pxTl = (((0 - observedOffset.x) - pivotX) / observedScale + pivotX) - centeringOffsetX
+                    val pyTl = (((0 - observedOffset.y) - pivotY) / observedScale + pivotY) - centeringOffsetY
+                    val pxBr = (((screenWidth - observedOffset.x) - pivotX) / observedScale + pivotX) - centeringOffsetX
+                    val pyBr = (((screenHeight - observedOffset.y) - pivotY) / observedScale + pivotY) - centeringOffsetY
+
+                    val qTop = pyTl.toInt() / (tileSizePx / 2)
+                    val qLeft = pxTl.toInt() / (tileSizePx / 2)
+                    val qBottom = pyBr.toInt() / (tileSizePx / 2)
+                    val qRight = pxBr.toInt() / (tileSizePx / 2)
+                    listOf(qTop, qLeft, qBottom, qRight, (observedScale * 10f).roundToInt())
+                } else {
+                    null
                 }
             }.conflate().collectLatest { _ ->
 
-                delay(150)
-
                 val tileCalcStart = System.nanoTime()
                 if (!isActive) return@collectLatest
 
-                if (isScrolling && effectiveScale > 1f) {
-                    return@collectLatest
-                }
+                val renderScale = latestEffectiveScale
+                val renderOffset = latestEffectiveOffset
 
                 val currentVisibleRect = visibleScreenRect()
 
@@ -1404,14 +1446,14 @@ internal fun PdfPageComposable(
                     val pivotX = screenWidth / 2f
                     val pivotY = screenHeight / 2f
 
-                    pxTl = (((0 - effectiveOffset.x) - pivotX) / effectiveScale + pivotX) - centeringOffsetX
-                    pyTl = (((0 - effectiveOffset.y) - pivotY) / effectiveScale + pivotY) - centeringOffsetY
-                    pxBr = (((screenWidth - effectiveOffset.x) - pivotX) / effectiveScale + pivotX) - centeringOffsetX
-                    pyBr = (((screenHeight - effectiveOffset.y) - pivotY) / effectiveScale + pivotY) - centeringOffsetY
+                    pxTl = (((0 - renderOffset.x) - pivotX) / renderScale + pivotX) - centeringOffsetX
+                    pyTl = (((0 - renderOffset.y) - pivotY) / renderScale + pivotY) - centeringOffsetY
+                    pxBr = (((screenWidth - renderOffset.x) - pivotX) / renderScale + pivotX) - centeringOffsetX
+                    pyBr = (((screenHeight - renderOffset.y) - pivotY) / renderScale + pivotY) - centeringOffsetY
                 }
 
                 val visibleBitmapRect = Rect(pxTl.toInt(), pyTl.toInt(), pxBr.toInt(), pyBr.toInt())
-                val inset = if (effectiveScale > 2f) 0 else -tileSizePx
+                val inset = if (renderScale > 2f) 0 else -tileSizePx
                 visibleBitmapRect.inset(inset, inset)
 
                 val requiredTileIds = mutableSetOf<Int>()
@@ -1431,8 +1473,10 @@ internal fun PdfPageComposable(
 
                 val currentTileIds = tiles.map { it.tileId }.toSet()
 
-                val scaleTolerance = 0.05f
-                val validCurrentTileIds = tiles.filter { abs(it.renderScale - effectiveScale) <= scaleTolerance }.map { it.tileId }.toSet()
+                val scaleTolerance = PDF_TILE_SCALE_TOLERANCE
+                val validCurrentTileIds = tiles.filter { abs(it.renderScale - renderScale) <= scaleTolerance }.map { it.tileId }.toSet()
+                val tilesToRenderIds = requiredTileIds - validCurrentTileIds
+                val tilesToRecycleIds = currentTileIds - requiredTileIds
 
                 val duration = (System.nanoTime() - tileCalcStart) / 1_000_000f
                 if (duration > 2f) {
@@ -1441,21 +1485,26 @@ internal fun PdfPageComposable(
                     )
                 }
 
-                if (requiredTileIds != validCurrentTileIds) {
-
-                    val tilesToRenderIds = requiredTileIds - validCurrentTileIds
-                    val tilesToRecycleIds = currentTileIds - requiredTileIds
-
-                    if (tilesToRecycleIds.isNotEmpty()) {
-                        val (tilesToRecycle, tilesToKeep) = tiles.partition { it.tileId in tilesToRecycleIds }
-                        tiles = tilesToKeep
-                        withContext(Dispatchers.IO) {
-                            tilesToRecycle.forEach { PdfBitmapPool.recycle(it.bitmap) }
-                        }
+                if (tilesToRecycleIds.isNotEmpty()) {
+                    val (tilesToRecycle, tilesToKeep) = tiles.partition { it.tileId in tilesToRecycleIds }
+                    tiles = tilesToKeep
+                    withContext(Dispatchers.IO) {
+                        tilesToRecycle.forEach { PdfBitmapPool.recycle(it.bitmap) }
                     }
+                }
 
+                if (isScrolling && renderScale > 1f) {
+                    return@collectLatest
+                }
+
+                if (requiredTileIds != validCurrentTileIds) {
                     if (tilesToRenderIds.isNotEmpty()) {
-                        withContext(Dispatchers.IO) {
+                        delay(PDF_TILE_IDLE_RENDER_DELAY_MS)
+                        if (!isActive) return@collectLatest
+                        if (isScrolling && latestEffectiveScale > 1f) return@collectLatest
+
+                        val renderedTiles = withContext(Dispatchers.IO) {
+                            val newTiles = mutableListOf<PdfTile>()
                             tilesToRenderIds.forEach { tileId ->
                                 if (!isActive) return@forEach
 
@@ -1469,14 +1518,18 @@ internal fun PdfPageComposable(
                                     (col + 1) * tileSizePx,
                                     (row + 1) * tileSizePx
                                 )
-                                val tileRenderSize = (tileSizePx * effectiveScale).toInt().coerceAtLeast(1)
+                                val tileRenderScale = min(
+                                    renderScale,
+                                    PDF_MAX_TILE_BITMAP_SIZE_PX.toFloat() / tileSizePx.toFloat()
+                                )
+                                val tileRenderSize = (tileSizePx * tileRenderScale).toInt().coerceAtLeast(1)
 
                                 val tileBitmap = PdfBitmapPool.get(tileRenderSize)
 
-                                val fullPageRenderWidth = (actualBitmapWidthPx * effectiveScale).toInt()
-                                val fullPageRenderHeight = (actualBitmapHeightPx * effectiveScale).toInt()
-                                val tileRenderX = (col * tileSizePx * effectiveScale).toInt()
-                                val tileRenderY = (row * tileSizePx * effectiveScale).toInt()
+                                val fullPageRenderWidth = (actualBitmapWidthPx * tileRenderScale).toInt()
+                                val fullPageRenderHeight = (actualBitmapHeightPx * tileRenderScale).toInt()
+                                val tileRenderX = (col * tileSizePx * tileRenderScale).toInt()
+                                val tileRenderY = (row * tileSizePx * tileRenderScale).toInt()
 
                                 page?.renderPageBitmap(
                                     bitmap = tileBitmap,
@@ -1487,24 +1540,26 @@ internal fun PdfPageComposable(
                                     renderAnnot = true
                                 )
 
-                                val newTile = PdfTile(tileBitmap, tileRect, tileId, effectiveScale)
-                                var handedOver = false
-                                try {
-                                    withContext(Dispatchers.Main) {
-                                        val oldTile = tiles.find { it.tileId == tileId }
-                                        tiles = tiles.filter { it.tileId != tileId } + newTile
-                                        handedOver = true
+                                newTiles += PdfTile(tileBitmap, tileRect, tileId, renderScale)
+                            }
+                            newTiles
+                        }
 
-                                        oldTile?.let {
-                                            coroutineScope.launch(Dispatchers.IO) {
-                                                PdfBitmapPool.recycle(it.bitmap)
-                                            }
-                                        }
-                                    }
-                                } finally {
-                                    if (!handedOver) {
-                                        PdfBitmapPool.recycle(tileBitmap)
-                                    }
+                        if (!isActive) {
+                            withContext(Dispatchers.IO) {
+                                renderedTiles.forEach { PdfBitmapPool.recycle(it.bitmap) }
+                            }
+                            return@collectLatest
+                        }
+
+                        if (renderedTiles.isNotEmpty()) {
+                            val renderedIds = renderedTiles.map { it.tileId }.toSet()
+                            val replacedTiles = tiles.filter { it.tileId in renderedIds }
+                            tiles = tiles.filterNot { it.tileId in renderedIds } + renderedTiles
+
+                            if (replacedTiles.isNotEmpty()) {
+                                coroutineScope.launch(Dispatchers.IO) {
+                                    replacedTiles.forEach { PdfBitmapPool.recycle(it.bitmap) }
                                 }
                             }
                         }
@@ -2799,7 +2854,7 @@ internal fun PdfPageComposable(
 
                                     Timber.tag("PdfLinkDiagnostic").i("Extracted docPtr: $docPtr | pagePtr: $pagePtr")
 
-                                    val linkInfo = NativePdfiumBridge.getLinkInfoAtPoint(
+                                    val linkInfo = PdfiumEngineProvider.bridge.getLinkInfoAtPoint(
                                         docPtr, pagePtr, pdfCoords.x.toDouble(), pdfCoords.y.toDouble()
                                     )
 
@@ -2818,7 +2873,7 @@ internal fun PdfPageComposable(
                                         }
                                     }
 
-                                    val clickHandled = NativePdfiumBridge.performClick(pagePtr, pdfCoords.x.toDouble(), pdfCoords.y.toDouble())
+                                    val clickHandled = PdfiumEngineProvider.bridge.performClick(pagePtr, pdfCoords.x.toDouble(), pdfCoords.y.toDouble())
                                     if (clickHandled) {
                                         return@withContext 2
                                     }
@@ -3007,25 +3062,21 @@ internal fun PdfPageComposable(
                 awaitEachGesture {
                     @Suppress("UnusedVariable", "Unused") val down =
                         awaitFirstDown(requireUnconsumed = false)
+                    paginationPanFlingJob?.cancel()
+                    paginationPanFlingJob = null
                     velocityTracker.resetTracking()
 
                     var mode = 0
                     var accumulatedZoom = 1f
                     var accumulatedPan = Offset.Zero
                     var swipeAccumulatorX = 0f
+                    var velocityAccumulator = Offset.Zero
 
                     do {
                         val event = awaitPointerEvent()
                         val canceled = event.changes.any { it.isConsumed }
                         val pointerCount = event.changes.size
 
-                        val currentCentroid = event.calculateCentroid(useCurrent = true)
-                        if (pointerCount > 0 && currentCentroid != Offset.Unspecified) {
-                            velocityTracker.addPosition(
-                                event.changes[0].uptimeMillis, currentCentroid
-                            )
-                        }
-
                         if (!canceled) {
                             val rawPanChange = event.calculatePan()
                             val panChange = if (isScrollLocked && pointerCount == 1) {
@@ -3077,6 +3128,14 @@ internal fun PdfPageComposable(
                                     Timber.tag("PdfZoomDebug").v("Panning: Offset $offset -> $newX, $newY (Max: $maxOffsetX, $maxOffsetY)")
                                     offset = Offset(newX, newY)
 
+                                    if (event.changes.isNotEmpty() && panChange != Offset.Zero) {
+                                        velocityAccumulator += panChange
+                                        velocityTracker.addPosition(
+                                            event.changes[0].uptimeMillis,
+                                            velocityAccumulator
+                                        )
+                                    }
+
                                     event.changes.forEach {
                                         if (it.positionChanged()) it.consume()
                                     }
@@ -3189,38 +3248,54 @@ internal fun PdfPageComposable(
                             }
                         }
                     } else if (mode == 1 && scale > 1f) {
-                        val velocity = velocityTracker.calculateVelocity()
                         val contentWidth = actualBitmapWidthPx * scale
                         val contentHeight = actualBitmapHeightPx * scale
                         val maxOffsetX = (contentWidth - size.width).coerceAtLeast(0f) / 2f
                         val maxOffsetY = (contentHeight - size.height).coerceAtLeast(0f) / 2f
 
-                        val startX = offset.x
-                        val startY = offset.y
+                        val velocity = velocityTracker.calculateVelocity()
+                        val flingX = if (!isScrollLocked && abs(velocity.x) > PDF_PAGINATION_PAN_FLING_MIN_VELOCITY) {
+                            velocity.x * PDF_PAGINATION_PAN_FLING_MULTIPLIER
+                        } else {
+                            0f
+                        }
+                        val flingY = if (abs(velocity.y) > PDF_PAGINATION_PAN_FLING_MIN_VELOCITY) {
+                            velocity.y * PDF_PAGINATION_PAN_FLING_MULTIPLIER
+                        } else {
+                            0f
+                        }
 
-                        coroutineScope.launch {
-                            coroutineScope {
-                                launch {
-                                    if (!isScrollLocked) {
-                                        Animatable(startX).animateDecay(
-                                            velocity.x, decay
-                                        ) {
-                                            val newX = value.coerceIn(
-                                                -maxOffsetX, maxOffsetX
-                                            )
-                                            offset = offset.copy(x = newX)
+                        if (flingX == 0f && flingY == 0f) {
+                            offset = Offset(
+                                x = offset.x.coerceIn(-maxOffsetX, maxOffsetX),
+                                y = offset.y.coerceIn(-maxOffsetY, maxOffsetY)
+                            )
+                        } else {
+                            val startOffset = offset
+                            paginationPanFlingJob = coroutineScope.launch {
+                                try {
+                                    coroutineScope {
+                                        launch {
+                                            if (flingX != 0f) {
+                                                Animatable(startOffset.x).animateDecay(flingX, decay) {
+                                                    offset = offset.copy(
+                                                        x = value.coerceIn(-maxOffsetX, maxOffsetX)
+                                                    )
+                                                }
+                                            }
+                                        }
+                                        launch {
+                                            if (flingY != 0f) {
+                                                Animatable(startOffset.y).animateDecay(flingY, decay) {
+                                                    offset = offset.copy(
+                                                        y = value.coerceIn(-maxOffsetY, maxOffsetY)
+                                                    )
+                                                }
+                                            }
                                         }
                                     }
-                                }
-                                launch {
-                                    Animatable(startY).animateDecay(
-                                        velocity.y, decay
-                                    ) {
-                                        val newY = value.coerceIn(
-                                            -maxOffsetY, maxOffsetY
-                                        )
-                                        offset = offset.copy(y = newY)
-                                    }
+                                } finally {
+                                    paginationPanFlingJob = null
                                 }
                             }
                         }
@@ -3256,7 +3331,7 @@ internal fun PdfPageComposable(
                         }
 
                         val buttons = currentEvent.buttons
-                        Timber.tag("StylusEraserDiagnostic").d(
+                        Timber.tag("StylusDebug").d(
                             "Page $pageIndex | Type: ${down.type} | isPrimary: ${buttons.isPrimaryPressed} | isSecondary: ${buttons.isSecondaryPressed} | isTertiary: ${buttons.isTertiaryPressed} | buttonsString: $buttons"
                         )
 
@@ -3881,7 +3956,10 @@ internal fun PdfPageComposable(
                         stableColorFilter,
                         isDarkMode,
                         excludeImages,
-                        stableImageRects
+                        stableImageRects,
+                        textureBitmap,
+                        effectiveTextureAlpha,
+                        textureBlendMode
                     ) {
                         Timber.tag("PdfDrawPerf").v(
                             "STATIC DATA GENERATED: Scale=$effectiveScale, Tiles=${stableTiles.item.size}"
@@ -3899,7 +3977,10 @@ internal fun PdfPageComposable(
                             colorFilter = stableColorFilter,
                             isDarkMode = isDarkMode,
                             excludeImages = excludeImages,
-                            imageRects = stableImageRects
+                            imageRects = stableImageRects,
+                            textureBitmap = StableHolder(textureBitmap),
+                            textureAlpha = effectiveTextureAlpha,
+                            textureBlendMode = textureBlendMode
                         )
                     }
 
@@ -4263,7 +4344,10 @@ private fun PdfBitmapLayer(
     colorFilter: ColorFilter? = null,
     isDarkMode: Boolean = false,
     excludeImages: Boolean = false,
-    imageRects: List<android.graphics.Rect> = emptyList()
+    imageRects: List<android.graphics.Rect> = emptyList(),
+    textureBitmap: ImageBitmap? = null,
+    textureAlpha: Float = 0f,
+    textureBlendMode: BlendMode = BlendMode.Multiply
 ) {
     Canvas(modifier = Modifier.fillMaxSize().graphicsLayer()) {
         translate(left = centeringOffsetX, top = centeringOffsetY) {
@@ -4363,6 +4447,15 @@ private fun PdfBitmapLayer(
                             }
                         }
                     }
+
+                    if (textureBitmap != null && textureAlpha > 0f) {
+                        drawRect(
+                            brush = ShaderBrush(ImageShader(textureBitmap, TileMode.Repeated, TileMode.Repeated)),
+                            size = Size(dstW.toFloat(), dstH.toFloat()),
+                            blendMode = textureBlendMode,
+                            alpha = textureAlpha
+                        )
+                    }
                 }
             }
         }
@@ -4884,7 +4977,10 @@ private fun PdfPageStaticLayer(data: PageStaticData) {
         colorFilter = data.colorFilter.item,
         isDarkMode = data.isDarkMode,
         excludeImages = data.excludeImages,
-        imageRects = data.imageRects.item
+        imageRects = data.imageRects.item,
+        textureBitmap = data.textureBitmap.item,
+        textureAlpha = data.textureAlpha,
+        textureBlendMode = data.textureBlendMode
     )
 }
 

app/src/main/java/com/aryan/reader/pdf/PdfPreferences.kt

@@ -7,6 +7,7 @@ import androidx.compose.ui.graphics.toArgb
 import androidx.core.content.edit
 import com.aryan.reader.BuildConfig
 import com.aryan.reader.ReaderTheme
+import com.aryan.reader.ReaderTexture
 import com.aryan.reader.epubreader.SystemUiMode
 
 internal const val VERTICAL_SCROLL_TAG = "PdfVerticalScroll"
@@ -39,6 +40,8 @@ private const val PREF_EXTERNAL_SEARCH_PKG = "external_search_package"
 private const val PDF_THEME_KEY = "pdf_reader_theme"
 private const val PDF_KEEP_SCREEN_ON_KEY = "pdf_keep_screen_on_enabled"
 private const val PDF_HIDDEN_TOOLS_KEY = "pdf_hidden_tools"
+private const val PDF_TOOL_ORDER_KEY = "pdf_tool_order"
+private const val PDF_BOTTOM_TOOLS_KEY = "pdf_bottom_tools"
 private const val PDF_SYSTEM_UI_MODE_KEY = "pdf_system_ui_mode"
 internal const val PDF_LAYOUT_DEBUG_TAG = "PdfLayoutDebug"
 
@@ -76,7 +79,13 @@ val PdfBuiltInThemes = listOf(
     ReaderTheme("dark", "Dark", Color(0xFF121212), Color(0xFFE0E0E0), true),
     ReaderTheme("sepia", "Sepia", Color(0xFFFBF0D9), Color(0xFF5F4B32), false),
     ReaderTheme("slate", "Slate", Color(0xFF2E3440), Color(0xFFECEFF4), true),
-    ReaderTheme("oled", "OLED", Color(0xFF000000), Color(0xFFB0B0B0), true)
+    ReaderTheme("oled", "OLED", Color(0xFF000000), Color(0xFFB0B0B0), true),
+    ReaderTheme("pdf_natural_white_texture", "Natural White", Color(0xFFF7F1E5), Color(0xFF1D1B18), false, textureId = ReaderTexture.NATURAL_WHITE.id),
+    ReaderTheme("pdf_retina_texture", "Retina", Color(0xFFF1E4CD), Color(0xFF2A2119), false, textureId = ReaderTexture.RETINA_WOOD.id),
+    ReaderTheme("pdf_veneer_texture", "Veneer", Color(0xFFF4E7CF), Color(0xFF2A2119), false, textureId = ReaderTexture.LIGHT_VENEER.id),
+    ReaderTheme("pdf_grey_wash_texture", "Grey Wash", Color(0xFF202124), Color(0xFFFFFFFF), true, textureId = ReaderTexture.GREY_WASH.id),
+    ReaderTheme("pdf_fabric_texture", "Fabric", Color(0xFF262626), Color(0xFFE8E2D8), true, textureId = ReaderTexture.CLASSY_FABRIC.id),
+    ReaderTheme("pdf_retro_texture", "Retro", Color(0xFFF6ECD8), Color(0xFF2F2118), false, textureId = ReaderTexture.RETRO_INTRO.id)
 )
 
 internal fun loadPdfHiddenTools(context: Context): Set<String> {
@@ -89,6 +98,32 @@ internal fun savePdfHiddenTools(context: Context, hiddenTools: Set<String>) {
     prefs.edit { putStringSet(PDF_HIDDEN_TOOLS_KEY, hiddenTools) }
 }
 
+internal fun loadPdfToolOrder(context: Context): List<PdfReaderTool> {
+    val prefs = context.getSharedPreferences(SETTINGS_PREFS_NAME, Context.MODE_PRIVATE)
+    val savedTools = prefs.getString(PDF_TOOL_ORDER_KEY, null)
+        ?.split(',')
+        ?.filter { it.isNotBlank() }
+        ?.mapNotNull { name -> PdfReaderTool.entries.firstOrNull { it.name == name } }
+        .orEmpty()
+    return (savedTools + PdfReaderTool.entries.filterNot { it in savedTools }).distinct()
+}
+
+internal fun savePdfToolOrder(context: Context, toolOrder: List<PdfReaderTool>) {
+    val prefs = context.getSharedPreferences(SETTINGS_PREFS_NAME, Context.MODE_PRIVATE)
+    prefs.edit { putString(PDF_TOOL_ORDER_KEY, toolOrder.joinToString(",") { it.name }) }
+}
+
+internal fun loadPdfBottomTools(context: Context): Set<String> {
+    val prefs = context.getSharedPreferences(SETTINGS_PREFS_NAME, Context.MODE_PRIVATE)
+    val defaultBottomTools = PdfReaderTool.entries.filter { it.category == "Bottom Bar" }.map { it.name }.toSet()
+    return prefs.getStringSet(PDF_BOTTOM_TOOLS_KEY, defaultBottomTools) ?: defaultBottomTools
+}
+
+internal fun savePdfBottomTools(context: Context, bottomTools: Set<String>) {
+    val prefs = context.getSharedPreferences(SETTINGS_PREFS_NAME, Context.MODE_PRIVATE)
+    prefs.edit { putStringSet(PDF_BOTTOM_TOOLS_KEY, bottomTools) }
+}
+
 internal fun loadCustomHighlightColors(context: Context): Map<PdfHighlightColor, Color> {
     val prefs = context.getSharedPreferences(SETTINGS_PREFS_NAME, Context.MODE_PRIVATE)
     return PdfHighlightColor.entries.associateWith {
@@ -139,7 +174,7 @@ internal fun loadPdfThemeId(context: Context): String {
 }
 
 internal fun loadUseOnlineDict(context: Context): Boolean {
-    @Suppress("KotlinConstantConditions") if (BuildConfig.FLAVOR == "oss") return false
+    @Suppress("KotlinConstantConditions") if (BuildConfig.FLAVOR == "oss" && BuildConfig.IS_OFFLINE) return false
     val prefs = context.getSharedPreferences(SETTINGS_PREFS_NAME, Context.MODE_PRIVATE)
     return prefs.getBoolean(PREF_USE_ONLINE_DICT, true)
 }

app/src/main/java/com/aryan/reader/pdf/PdfSettingsSheets.kt

@@ -1,8 +1,9 @@
-@file:kotlin.OptIn(ExperimentalMaterial3Api::class)
+@file:OptIn(ExperimentalMaterial3Api::class)
 
 package com.aryan.reader.pdf
 
 import androidx.compose.foundation.clickable
+import androidx.compose.foundation.gestures.detectDragGesturesAfterLongPress
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.Row
@@ -11,94 +12,346 @@ import androidx.compose.foundation.layout.WindowInsets
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.navigationBars
-import androidx.compose.foundation.layout.padding
-import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.background
+import androidx.compose.foundation.gestures.detectDragGestures
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.foundation.lazy.LazyListState
 import androidx.compose.foundation.lazy.items
+import androidx.compose.foundation.lazy.rememberLazyListState
+import androidx.compose.ui.graphics.graphicsLayer
+import androidx.compose.ui.zIndex
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.windowInsetsPadding
+import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.filled.Close
+import androidx.compose.material.icons.filled.Edit
+import androidx.compose.material.icons.filled.LockOpen
+import androidx.compose.material.icons.filled.Menu
+import androidx.compose.material.icons.filled.MoreVert
+import androidx.compose.material.icons.filled.Search
+import androidx.compose.material.icons.filled.Check
 import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.Icon
 import androidx.compose.material3.IconButton
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.ModalBottomSheet
-import androidx.compose.material3.Switch
 import androidx.compose.material3.Text
 import androidx.compose.material3.rememberModalBottomSheetState
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.clip
+import androidx.compose.ui.geometry.Offset
+import androidx.compose.ui.geometry.Rect
+import androidx.compose.ui.input.pointer.pointerInput
+import androidx.compose.ui.layout.boundsInWindow
+import androidx.compose.ui.layout.onGloballyPositioned
+import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.unit.dp
+import androidx.compose.ui.window.Dialog
+import androidx.compose.ui.window.DialogProperties
 import com.aryan.reader.R
 import com.aryan.reader.epubreader.OptionSegmentedControl
 import com.aryan.reader.epubreader.SystemUiMode
 
+
+enum class PdfFlatItemType { SECTION_HEADER, TOOL, EMPTY_PLACEHOLDER, MORE_HEADER, MORE_TOOL }
+
+data class PdfFlatToolItem(
+    val id: String,
+    val type: PdfFlatItemType,
+    val tool: PdfReaderTool? = null,
+    val section: PdfToolbarSection? = null,
+    val title: String? = null
+)
+
+fun sanitizePdfPlaceholders(list: List<PdfFlatToolItem>): List<PdfFlatToolItem> {
+    val result = mutableListOf<PdfFlatToolItem>()
+    val sectionMap = mutableMapOf<PdfToolbarSection, MutableList<PdfFlatToolItem>>()
+    PdfToolbarSection.entries.forEach { sectionMap[it] = mutableListOf() }
+
+    list.forEach { item ->
+        if (item.type == PdfFlatItemType.TOOL) {
+            item.section?.let { sectionMap[it]?.add(item) }
+        }
+    }
+
+    PdfToolbarSection.entries.forEach { section ->
+        result.add(PdfFlatToolItem("header_${section.name}", PdfFlatItemType.SECTION_HEADER, section = section, title = section.title))
+        val tools = sectionMap[section] ?: emptyList()
+        if (tools.isEmpty()) {
+            result.add(PdfFlatToolItem("empty_${section.name}", PdfFlatItemType.EMPTY_PLACEHOLDER, section = section))
+        } else {
+            result.addAll(tools)
+        }
+    }
+
+    list.filter { it.type == PdfFlatItemType.MORE_HEADER || it.type == PdfFlatItemType.MORE_TOOL }.forEach {
+        result.add(it)
+    }
+
+    return result
+}
+
+class PdfDragDropState(
+    val lazyListState: LazyListState,
+    val onMove: (String, String) -> Unit
+) {
+    var draggedItemId by mutableStateOf<String?>(null)
+    var dragOffset by mutableStateOf(Offset.Zero)
+
+    fun onDragStart(id: String) { draggedItemId = id; dragOffset = Offset.Zero }
+    fun onDrag(delta: Offset) {
+        val draggedId = draggedItemId ?: return
+        dragOffset += delta
+        val visibleItems = lazyListState.layoutInfo.visibleItemsInfo
+        val currentItem = visibleItems.find { it.key == draggedId } ?: return
+        val center = currentItem.offset + dragOffset.y + currentItem.size / 2f
+        val targetItem = visibleItems.find { it.key != draggedId && center >= it.offset && center <= (it.offset + it.size) }
+        if (targetItem != null) {
+            onMove(draggedId, targetItem.key.toString())
+            dragOffset = dragOffset.copy(y = dragOffset.y - (targetItem.offset - currentItem.offset))
+        }
+    }
+    fun onDragEnd() { draggedItemId = null; dragOffset = Offset.Zero }
+}
+
+@OptIn(ExperimentalMaterial3Api::class)
 @Composable
 fun PdfCustomizeToolsSheet(
     hiddenTools: Set<String>,
+    toolOrder: List<PdfReaderTool>,
+    bottomTools: Set<String>,
     onUpdate: (Set<String>) -> Unit,
+    onOrderUpdate: (List<PdfReaderTool>) -> Unit,
+    onPlacementUpdate: (Set<String>) -> Unit,
     onDismiss: () -> Unit
 ) {
-    ModalBottomSheet(
-        onDismissRequest = onDismiss,
-        contentWindowInsets = { WindowInsets.navigationBars }
-    ) {
-        Column(modifier = Modifier.padding(horizontal = 24.dp).padding(bottom = 24.dp)) {
-            Text(
-                text = stringResource(R.string.title_customize_toolbar),
-                style = MaterialTheme.typography.headlineSmall,
-                fontWeight = FontWeight.Bold,
-                color = MaterialTheme.colorScheme.onSurface
-            )
-            Spacer(modifier = Modifier.height(8.dp))
-            Text(
-                text = stringResource(R.string.desc_customize_toolbar),
-                style = MaterialTheme.typography.bodyMedium,
-                color = MaterialTheme.colorScheme.onSurfaceVariant
-            )
-            Spacer(modifier = Modifier.height(16.dp))
+    val reorderableToolbarTools = setOf(
+        PdfReaderTool.DICTIONARY, PdfReaderTool.THEME, PdfReaderTool.LOCK_PANNING,
+        PdfReaderTool.SLIDER, PdfReaderTool.TOC, PdfReaderTool.SEARCH,
+        PdfReaderTool.HIGHLIGHT_ALL, PdfReaderTool.AI_FEATURES,
+        PdfReaderTool.EDIT_MODE, PdfReaderTool.TTS_CONTROLS
+    )
 
-            LazyColumn(modifier = Modifier.fillMaxWidth()) {
-                PdfReaderTool.entries.groupBy { it.category }.forEach { (category, tools) ->
-                    item {
-                        Text(
-                            text = category,
-                            style = MaterialTheme.typography.labelMedium,
-                            color = MaterialTheme.colorScheme.primary,
-                            modifier = Modifier.padding(top = 16.dp, bottom = 8.dp)
-                        )
+    var localHiddenTools by remember { mutableStateOf(hiddenTools) }
+    var flatItems by remember {
+        mutableStateOf<List<PdfFlatToolItem>>(
+            run {
+                val toolbarTools = toolOrder.filter { it in reorderableToolbarTools }
+                val topTools = toolbarTools.filter { !bottomTools.contains(it.name) && !hiddenTools.contains(it.name) }
+                val bottomToolsList = toolbarTools.filter { bottomTools.contains(it.name) && !hiddenTools.contains(it.name) }
+                val hiddenToolsList = toolbarTools.filter { hiddenTools.contains(it.name) }
+                val moreTools = toolOrder.filter { it !in reorderableToolbarTools }
+
+                val list = mutableListOf<PdfFlatToolItem>()
+
+                PdfToolbarSection.entries.forEach { section ->
+                    val tools = when(section) {
+                        PdfToolbarSection.TOP -> topTools
+                        PdfToolbarSection.BOTTOM -> bottomToolsList
+                        PdfToolbarSection.HIDDEN -> hiddenToolsList
                     }
-                    items(tools) { tool ->
-                        Row(
+                    list.add(PdfFlatToolItem("header_${section.name}", PdfFlatItemType.SECTION_HEADER, section = section, title = section.title))
+                    if (tools.isEmpty()) {
+                        list.add(PdfFlatToolItem("empty_${section.name}", PdfFlatItemType.EMPTY_PLACEHOLDER, section = section))
+                    } else {
+                        tools.forEach { tool ->
+                            list.add(PdfFlatToolItem("tool_${tool.name}", PdfFlatItemType.TOOL, tool = tool, section = section))
+                        }
+                    }
+                }
+
+                list.add(PdfFlatToolItem("more_header", PdfFlatItemType.MORE_HEADER, title = "More menu"))
+                moreTools.forEach { tool ->
+                    list.add(PdfFlatToolItem("more_${tool.name}", PdfFlatItemType.MORE_TOOL, tool = tool))
+                }
+                list
+            }
+        )
+    }
+
+    val commitDragDrop = {
+        val newHidden = localHiddenTools.filter { toolName ->
+            toolOrder.find { it.name == toolName } !in reorderableToolbarTools
+        }.toMutableSet()
+
+        val newBottom = mutableSetOf<String>()
+        val newOrder = mutableListOf<PdfReaderTool>()
+
+        flatItems.forEach { item ->
+            if (item.type == PdfFlatItemType.TOOL && item.tool != null) {
+                newOrder.add(item.tool)
+                if (item.section == PdfToolbarSection.HIDDEN) newHidden.add(item.tool.name)
+                if (item.section == PdfToolbarSection.BOTTOM) newBottom.add(item.tool.name)
+            }
+        }
+
+        val moreTools = flatItems.filter { it.type == PdfFlatItemType.MORE_TOOL }.mapNotNull { it.tool }
+        newOrder.addAll(moreTools)
+
+        localHiddenTools = newHidden
+        onUpdate(newHidden)
+        onPlacementUpdate(newBottom)
+        onOrderUpdate(newOrder)
+    }
+
+    val lazyListState = rememberLazyListState()
+    val dragDropState = remember {
+        PdfDragDropState(lazyListState) { fromKey, toKey ->
+            val fromIndex = flatItems.indexOfFirst { it.id == fromKey }
+            val toIndex = flatItems.indexOfFirst { it.id == toKey }
+            if (fromIndex == -1 || toIndex == -1 || fromIndex == toIndex) return@PdfDragDropState
+
+            val fromItem = flatItems[fromIndex]
+            if (fromItem.type != PdfFlatItemType.TOOL) return@PdfDragDropState
+
+            val toItem = flatItems[toIndex]
+            if (toItem.type == PdfFlatItemType.MORE_HEADER || toItem.type == PdfFlatItemType.MORE_TOOL) return@PdfDragDropState
+
+            val newList = flatItems.toMutableList()
+            val movedItem = newList.removeAt(fromIndex)
+
+            val newToIndex = newList.indexOfFirst { it.id == toKey }
+            val insertIndex = if (fromIndex < toIndex) newToIndex + 1 else newToIndex
+
+            newList.add(insertIndex, movedItem)
+
+            var actualSection = movedItem.section
+            for (i in insertIndex downTo 0) {
+                val item = newList[i]
+                if (item.type == PdfFlatItemType.SECTION_HEADER) {
+                    actualSection = item.section
+                    break
+                }
+            }
+
+            newList[insertIndex] = movedItem.copy(section = actualSection)
+            flatItems = newList
+        }
+    }
+
+    Dialog(
+        onDismissRequest = onDismiss,
+        properties = DialogProperties(usePlatformDefaultWidth = false)
+    ) {
+        androidx.compose.material3.Surface(
+            modifier = Modifier
+                .fillMaxSize()
+                .windowInsetsPadding(WindowInsets.navigationBars),
+            color = MaterialTheme.colorScheme.surface
+        ) {
+            Column(modifier = Modifier.fillMaxSize().padding(horizontal = 20.dp)) {
+                Row(
+                    modifier = Modifier.fillMaxWidth().padding(vertical = 16.dp),
+                    verticalAlignment = Alignment.CenterVertically
+                ) {
+                    Text(
+                        text = stringResource(R.string.title_customize_toolbar),
+                        style = MaterialTheme.typography.headlineSmall,
+                        fontWeight = FontWeight.Bold,
+                        color = MaterialTheme.colorScheme.onSurface,
+                        modifier = Modifier.weight(1f)
+                    )
+                    IconButton(onClick = onDismiss) {
+                        Icon(Icons.Default.Close, contentDescription = stringResource(R.string.action_close))
+                    }
+                }
+
+                LazyColumn(
+                    state = lazyListState,
+                    modifier = Modifier.fillMaxSize(),
+                    contentPadding = PaddingValues(bottom = 24.dp)
+                ) {
+                    items(flatItems, key = { it.id }) { item ->
+                        val isDragged = item.id == dragDropState.draggedItemId
+                        val zIndex = if (isDragged) 1f else 0f
+                        val elevation = if (isDragged) 8.dp else 0.dp
+                        val scale = if (isDragged) 1.03f else 1f
+                        val translationY = if (isDragged) dragDropState.dragOffset.y else 0f
+
+                        Box(
                             modifier = Modifier
                                 .fillMaxWidth()
-                                .clip(RoundedCornerShape(8.dp))
-                                .clickable {
-                                    val newSet = hiddenTools.toMutableSet()
-                                    if (newSet.contains(tool.name)) newSet.remove(tool.name)
-                                    else newSet.add(tool.name)
-                                    onUpdate(newSet)
+                                .then(if (isDragged) Modifier else Modifier.animateItem())
+                                .zIndex(zIndex)
+                                .graphicsLayer {
+                                    this.translationY = translationY
+                                    this.scaleX = scale
+                                    this.scaleY = scale
+                                    this.shadowElevation = elevation.toPx()
                                 }
-                                .padding(vertical = 12.dp, horizontal = 8.dp),
-                            verticalAlignment = Alignment.CenterVertically,
-                            horizontalArrangement = Arrangement.SpaceBetween
                         ) {
-                            Text(
-                                text = tool.title,
-                                style = MaterialTheme.typography.bodyLarge,
-                                color = MaterialTheme.colorScheme.onSurface
-                            )
-                            Switch(
-                                checked = !hiddenTools.contains(tool.name),
-                                onCheckedChange = { isVisible ->
-                                    val newSet = hiddenTools.toMutableSet()
-                                    if (isVisible) newSet.remove(tool.name) else newSet.add(tool.name)
-                                    onUpdate(newSet)
+                            when (item.type) {
+                                PdfFlatItemType.SECTION_HEADER -> {
+                                    Text(
+                                        text = item.title ?: "",
+                                        style = MaterialTheme.typography.titleMedium,
+                                        fontWeight = FontWeight.Bold,
+                                        color = MaterialTheme.colorScheme.onSurface,
+                                        modifier = Modifier.padding(top = 16.dp, bottom = 8.dp, start = 4.dp)
+                                    )
                                 }
-                            )
+                                PdfFlatItemType.EMPTY_PLACEHOLDER -> {
+                                    Box(
+                                        modifier = Modifier
+                                            .fillMaxWidth()
+                                            .height(64.dp)
+                                            .padding(vertical = 4.dp)
+                                            .background(MaterialTheme.colorScheme.surfaceVariant.copy(alpha = 0.3f), RoundedCornerShape(12.dp)),
+                                        contentAlignment = Alignment.Center
+                                    ) {
+                                        Text("Drop tools here", color = MaterialTheme.colorScheme.onSurfaceVariant)
+                                    }
+                                }
+                                PdfFlatItemType.TOOL -> {
+                                    PdfToolbarDragRow(
+                                        tool = item.tool!!,
+                                        isDragging = isDragged,
+                                        onDragStart = { dragDropState.onDragStart(item.id) },
+                                        onDrag = { dragDropState.onDrag(it) },
+                                        onDragEnd = {
+                                            dragDropState.onDragEnd()
+                                            flatItems = sanitizePdfPlaceholders(flatItems).toList()
+                                            commitDragDrop()
+                                        }
+                                    )
+                                }
+                                PdfFlatItemType.MORE_HEADER -> {
+                                    Text(
+                                        text = item.title ?: "More menu",
+                                        style = MaterialTheme.typography.labelMedium,
+                                        color = MaterialTheme.colorScheme.primary,
+                                        modifier = Modifier.padding(top = 24.dp, bottom = 8.dp, start = 4.dp)
+                                    )
+                                }
+                                PdfFlatItemType.MORE_TOOL -> {
+                                    PdfMoreToolVisibilityRow(
+                                        title = item.tool!!.title,
+                                        visible = !localHiddenTools.contains(item.tool.name),
+                                        onToggle = {
+                                            localHiddenTools = if (localHiddenTools.contains(item.tool.name)) {
+                                                localHiddenTools - item.tool.name
+                                            } else {
+                                                localHiddenTools + item.tool.name
+                                            }
+                                            onUpdate(localHiddenTools)
+                                        }
+                                    )
+                                }
+                            }
                         }
                     }
                 }
@@ -107,6 +360,154 @@ fun PdfCustomizeToolsSheet(
     }
 }
 
+@Composable
+private fun PdfToolbarDragRow(
+    tool: PdfReaderTool,
+    isDragging: Boolean,
+    onDragStart: () -> Unit,
+    onDrag: (Offset) -> Unit,
+    onDragEnd: () -> Unit
+) {
+    androidx.compose.material3.Surface(
+        modifier = Modifier
+            .fillMaxWidth()
+            .padding(vertical = 4.dp),
+        shape = RoundedCornerShape(12.dp),
+        color = if (isDragging) MaterialTheme.colorScheme.primaryContainer else MaterialTheme.colorScheme.surfaceVariant.copy(alpha = 0.5f)
+    ) {
+        Row(
+            modifier = Modifier.padding(start = 16.dp, top = 8.dp, bottom = 8.dp, end = 4.dp),
+            verticalAlignment = Alignment.CenterVertically
+        ) {
+            PdfToolPreviewIcon(tool)
+            Spacer(Modifier.width(16.dp))
+            Text(
+                text = tool.title,
+                style = MaterialTheme.typography.bodyLarge,
+                color = MaterialTheme.colorScheme.onSurface,
+                modifier = Modifier.weight(1f)
+            )
+            Icon(
+                Icons.Default.Menu,
+                contentDescription = "Drag to reorder",
+                tint = MaterialTheme.colorScheme.onSurfaceVariant,
+                modifier = Modifier
+                    .size(48.dp)
+                    .padding(12.dp)
+                    .pointerInput(tool) {
+                        detectDragGestures(
+                            onDragStart = { onDragStart() },
+                            onDrag = { change, dragAmount ->
+                                change.consume()
+                                onDrag(dragAmount)
+                            },
+                            onDragEnd = onDragEnd,
+                            onDragCancel = onDragEnd
+                        )
+                    }
+            )
+        }
+    }
+}
+
+@Composable
+private fun PdfToolbarDragRow(
+    tool: PdfReaderTool,
+    isDragging: Boolean,
+    onBounds: (Rect) -> Unit,
+    onDragStart: (Offset) -> Unit,
+    onDrag: (Offset) -> Unit,
+    onDragEnd: () -> Unit
+) {
+    var bounds by remember { mutableStateOf<Rect?>(null) }
+    androidx.compose.material3.Surface(
+        modifier = Modifier
+            .fillMaxWidth()
+            .padding(vertical = 4.dp)
+            .onGloballyPositioned {
+                bounds = it.boundsInWindow()
+                onBounds(it.boundsInWindow())
+            }
+            .pointerInput(tool) {
+                detectDragGesturesAfterLongPress(
+                    onDragStart = { onDragStart(bounds?.center ?: Offset.Zero) },
+                    onDragEnd = onDragEnd,
+                    onDragCancel = onDragEnd,
+                    onDrag = { change, dragAmount ->
+                        change.consume()
+                        onDrag(dragAmount)
+                    }
+                )
+            },
+        shape = RoundedCornerShape(12.dp),
+        color = if (isDragging) MaterialTheme.colorScheme.primaryContainer else MaterialTheme.colorScheme.surface
+    ) {
+        Row(
+            modifier = Modifier.padding(horizontal = 12.dp, vertical = 12.dp),
+            verticalAlignment = Alignment.CenterVertically
+        ) {
+            PdfToolPreviewIcon(tool)
+            Spacer(Modifier.width(12.dp))
+            Text(
+                text = tool.title,
+                style = MaterialTheme.typography.bodyLarge,
+                color = MaterialTheme.colorScheme.onSurface,
+                modifier = Modifier.weight(1f)
+            )
+            Icon(Icons.Default.Menu, contentDescription = null, tint = MaterialTheme.colorScheme.onSurfaceVariant)
+        }
+    }
+}
+
+@Composable
+private fun PdfMoreToolVisibilityRow(
+    title: String,
+    visible: Boolean,
+    onToggle: () -> Unit
+) {
+    Row(
+        modifier = Modifier
+            .fillMaxWidth()
+            .clip(RoundedCornerShape(8.dp))
+            .clickable(onClick = onToggle)
+            .padding(vertical = 12.dp, horizontal = 8.dp),
+        verticalAlignment = Alignment.CenterVertically
+    ) {
+        Text(
+            text = title,
+            style = MaterialTheme.typography.bodyLarge,
+            color = MaterialTheme.colorScheme.onSurface,
+            modifier = Modifier.weight(1f)
+        )
+        if (visible) {
+            Icon(Icons.Default.Check, contentDescription = null, tint = MaterialTheme.colorScheme.primary)
+        }
+    }
+}
+
+enum class PdfToolbarSection(val title: String) {
+    TOP("Top Bar"),
+    BOTTOM("Bottom Bar"),
+    HIDDEN("Hidden Tools")
+}
+
+@Composable
+private fun PdfToolPreviewIcon(tool: PdfReaderTool) {
+    when (tool) {
+        PdfReaderTool.DICTIONARY -> Icon(painterResource(id = R.drawable.dictionary), contentDescription = tool.title, modifier = Modifier.size(20.dp))
+        PdfReaderTool.THEME -> Icon(painterResource(id = R.drawable.palette), contentDescription = tool.title, modifier = Modifier.size(20.dp))
+        PdfReaderTool.LOCK_PANNING -> Icon(Icons.Default.LockOpen, contentDescription = tool.title, modifier = Modifier.size(20.dp))
+        PdfReaderTool.SLIDER -> Icon(painterResource(id = R.drawable.slider), contentDescription = tool.title, modifier = Modifier.size(20.dp))
+        PdfReaderTool.TOC -> Icon(Icons.Default.Menu, contentDescription = tool.title, modifier = Modifier.size(20.dp))
+        PdfReaderTool.SEARCH -> Icon(Icons.Default.Search, contentDescription = tool.title, modifier = Modifier.size(20.dp))
+        PdfReaderTool.HIGHLIGHT_ALL -> Icon(painterResource(id = R.drawable.highlight_text), contentDescription = tool.title, modifier = Modifier.size(20.dp))
+        PdfReaderTool.AI_FEATURES -> Icon(painterResource(id = R.drawable.ai), contentDescription = tool.title, modifier = Modifier.size(20.dp))
+        PdfReaderTool.EDIT_MODE -> Icon(Icons.Default.Edit, contentDescription = tool.title, modifier = Modifier.size(20.dp))
+        PdfReaderTool.TTS_CONTROLS -> Icon(painterResource(id = R.drawable.text_to_speech), contentDescription = tool.title, modifier = Modifier.size(20.dp))
+        else -> Icon(Icons.Default.MoreVert, contentDescription = tool.title, modifier = Modifier.size(20.dp))
+    }
+}
+
 @Composable
 fun PdfVisualOptionsSheet(
     systemUiMode: SystemUiMode,

app/src/main/java/com/aryan/reader/pdf/PdfToHtmlGenerator.kt

@@ -34,7 +34,9 @@ object PdfToHtmlGenerator {
         }
 
         try {
-            val doc = pdfiumCore.newDocument(pfd)
+            val doc = PdfiumEngineProvider.withPdfium {
+                pdfiumCore.newDocument(pfd)
+            }
             val totalPages = doc.getPageCount()
             Timber.tag(TAG).d("Document loaded. Total pages: $totalPages")
 
@@ -56,7 +58,9 @@ object PdfToHtmlGenerator {
                 writer.write(buildGlobalHtmlFooter())
             }
 
-            doc.close()
+            PdfiumEngineProvider.withPdfium {
+                doc.close()
+            }
             pfd.close()
             Timber.tag(TAG).d("generateHtmlFile SUCCESS | ${System.currentTimeMillis() - t0}ms")
             return@withContext true
@@ -137,14 +141,14 @@ object PdfToHtmlGenerator {
                     val textPagePtr = getNativePointer(textPage)
 
                     val imageElements = mutableListOf<ImageElement>()
-                    val objCount = NativePdfiumBridge.getPageObjectCount(pagePtr)
+                    val objCount = PdfiumEngineProvider.bridge.getPageObjectCount(pagePtr)
                     for (i in 0 until objCount) {
-                        if (NativePdfiumBridge.getPageObjectType(pagePtr, i) == 3) {
+                        if (PdfiumEngineProvider.bridge.getPageObjectType(pagePtr, i) == 3) {
                             val bbox = FloatArray(4)
-                            if (NativePdfiumBridge.getPageObjectBoundingBox(pagePtr, i, bbox)) {
+                            if (PdfiumEngineProvider.bridge.getPageObjectBoundingBox(pagePtr, i, bbox)) {
                                 val topY = bbox[3]
                                 val dimens = IntArray(2)
-                                val pixels = NativePdfiumBridge.extractImagePixels(pagePtr, i, dimens)
+                                val pixels = PdfiumEngineProvider.bridge.extractImagePixels(pagePtr, i, dimens)
                                 if (pixels != null && dimens[0] > 0 && dimens[1] > 0) {
                                     try {
                                         val bmp = Bitmap.createBitmap(pixels, dimens[0], dimens[1], Bitmap.Config.ARGB_8888)
@@ -175,11 +179,11 @@ object PdfToHtmlGenerator {
                     val flags: IntArray?
                     val charBoxes: FloatArray?
 
-                    synchronized(NativePdfiumBridge::class.java) {
-                        sizes     = NativePdfiumBridge.getPageFontSizes(textPagePtr, actualCount)
-                        weights   = NativePdfiumBridge.getPageFontWeights(textPagePtr, actualCount)
-                        flags     = NativePdfiumBridge.getPageFontFlags(textPagePtr, actualCount)
-                        charBoxes = NativePdfiumBridge.getPageCharBoxes(textPagePtr, actualCount)
+                    synchronized(PdfiumEngineProvider.lock) {
+                        sizes     = PdfiumEngineProvider.bridge.getPageFontSizes(textPagePtr, actualCount)
+                        weights   = PdfiumEngineProvider.bridge.getPageFontWeights(textPagePtr, actualCount)
+                        flags     = PdfiumEngineProvider.bridge.getPageFontFlags(textPagePtr, actualCount)
+                        charBoxes = PdfiumEngineProvider.bridge.getPageCharBoxes(textPagePtr, actualCount)
                     }
 
                     if (sizes == null || weights == null || flags == null) {

app/src/main/java/com/aryan/reader/pdf/PdfToolbars.kt

@@ -18,13 +18,14 @@ import androidx.compose.foundation.rememberScrollState
 import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.automirrored.filled.ArrowBack
-import androidx.compose.material.icons.automirrored.filled.Undo
+import androidx.compose.material.icons.automirrored.filled.ArrowForward
 import androidx.compose.material.icons.filled.*
 import androidx.compose.material3.*
 import androidx.compose.runtime.*
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.clip
+import androidx.compose.ui.draw.rotate
 import androidx.compose.ui.focus.FocusRequester
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.res.painterResource
@@ -33,6 +34,7 @@ import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.text.style.TextOverflow
 import androidx.compose.ui.unit.Dp
 import androidx.compose.ui.unit.dp
+import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.platform.testTag
 import androidx.compose.ui.unit.sp
 import com.aryan.reader.BuildConfig
@@ -41,9 +43,23 @@ import com.aryan.reader.R
 import com.aryan.reader.SearchState
 import com.aryan.reader.SearchTopBar
 import com.aryan.reader.TooltipIconButton
+import com.aryan.reader.areReaderAiFeaturesEnabled
 import com.aryan.reader.epubreader.SystemUiMode
 import kotlin.collections.isNotEmpty
 
+private val pdfToolbarTools = setOf(
+    PdfReaderTool.DICTIONARY,
+    PdfReaderTool.THEME,
+    PdfReaderTool.LOCK_PANNING,
+    PdfReaderTool.SLIDER,
+    PdfReaderTool.TOC,
+    PdfReaderTool.SEARCH,
+    PdfReaderTool.HIGHLIGHT_ALL,
+    PdfReaderTool.AI_FEATURES,
+    PdfReaderTool.EDIT_MODE,
+    PdfReaderTool.TTS_CONTROLS
+)
+
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
 internal fun PdfTopBar(
@@ -60,6 +76,8 @@ internal fun PdfTopBar(
     totalPages: Int,
     pagerStatePageCount: Int,
     hiddenTools: Set<String>,
+    toolOrder: List<PdfReaderTool>,
+    bottomTools: Set<String>,
     isScrollLocked: Boolean,
     isEditMode: Boolean,
     displayMode: DisplayMode,
@@ -83,6 +101,16 @@ internal fun PdfTopBar(
     onShowCustomizeTools: () -> Unit,
     onShowOcrLanguage: () -> Unit,
     onShowVisualOptions: () -> Unit,
+    onShowSlider: () -> Unit,
+    onShowToc: () -> Unit,
+    onSearchClick: () -> Unit,
+    onToggleHighlights: () -> Unit,
+    onShowAiHub: () -> Unit,
+    onToggleEditMode: () -> Unit,
+    onToggleTts: () -> Unit,
+    isTtsPlayingOrLoading: Boolean,
+    showAllTextHighlights: Boolean,
+    isHighlightingLoading: Boolean,
     tapToNavigateEnabled: Boolean,
     onToggleTapToNavigate: () -> Unit,
     onChangeDisplayMode: (DisplayMode) -> Unit,
@@ -153,35 +181,89 @@ internal fun PdfTopBar(
                             modifier = Modifier.padding(start = 12.dp).weight(1f).testTag("PageNumberIndicator")
                         )
 
-                        if (!hiddenTools.contains(PdfReaderTool.THEME.name)) {
-                            TooltipIconButton(
-                                text = stringResource(R.string.tooltip_theme),
-                                description = stringResource(R.string.tooltip_theme_desc),
-                                onClick = onShowThemePanel
-                            ) {
-                                Icon(painterResource(id = R.drawable.palette), contentDescription = stringResource(R.string.tooltip_theme_desc), tint = MaterialTheme.colorScheme.onSurfaceVariant)
+                        toolOrder
+                            .filter { it in pdfToolbarTools && !bottomTools.contains(it.name) && !hiddenTools.contains(it.name) }
+                            .forEach { tool ->
+                                when (tool) {
+                                    PdfReaderTool.THEME -> TooltipIconButton(
+                                        text = stringResource(R.string.tooltip_theme),
+                                        description = stringResource(R.string.tooltip_theme_desc),
+                                        onClick = onShowThemePanel
+                                    ) {
+                                        Icon(painterResource(id = R.drawable.palette), contentDescription = stringResource(R.string.tooltip_theme_desc), tint = MaterialTheme.colorScheme.onSurfaceVariant)
+                                    }
+                                    PdfReaderTool.LOCK_PANNING -> TooltipIconButton(
+                                        text = if (isScrollLocked) stringResource(R.string.tooltip_unlock_pan) else stringResource(R.string.tooltip_lock_pan),
+                                        description = if (isScrollLocked) stringResource(R.string.tooltip_unlock_pan_desc) else stringResource(R.string.tooltip_lock_pan_desc),
+                                        onClick = onToggleScrollLock
+                                    ) {
+                                        Icon(if (isScrollLocked) Icons.Default.Lock else Icons.Default.LockOpen, contentDescription = if (isScrollLocked) stringResource(R.string.tooltip_unlock_pan) else stringResource(R.string.tooltip_lock_pan), tint = MaterialTheme.colorScheme.onSurfaceVariant)
+                                    }
+                                    PdfReaderTool.DICTIONARY -> TooltipIconButton(
+                                        text = stringResource(R.string.tooltip_dictionary),
+                                        description = stringResource(R.string.tooltip_dictionary_desc),
+                                        onClick = onShowDictionarySettings
+                                    ) {
+                                        Icon(painterResource(id = R.drawable.dictionary), contentDescription = stringResource(R.string.content_desc_dictionary_settings), tint = MaterialTheme.colorScheme.onSurfaceVariant)
+                                    }
+                                    PdfReaderTool.SLIDER -> TooltipIconButton(
+                                        text = stringResource(R.string.tooltip_slider),
+                                        description = stringResource(R.string.tooltip_slider_desc),
+                                        onClick = onShowSlider,
+                                        enabled = !isTtsPlayingOrLoading
+                                    ) {
+                                        Icon(painterResource(id = R.drawable.slider), contentDescription = stringResource(R.string.content_desc_navigate_slider))
+                                    }
+                                    PdfReaderTool.TOC -> TooltipIconButton(
+                                        text = stringResource(R.string.tooltip_toc),
+                                        description = stringResource(R.string.tooltip_toc_desc),
+                                        onClick = onShowToc,
+                                        enabled = !isTtsPlayingOrLoading
+                                    ) {
+                                        Icon(Icons.Default.Menu, contentDescription = stringResource(R.string.content_desc_table_of_contents))
+                                    }
+                                    PdfReaderTool.SEARCH -> TooltipIconButton(
+                                        text = stringResource(R.string.tooltip_search),
+                                        description = stringResource(R.string.tooltip_search_desc),
+                                        onClick = onSearchClick,
+                                        enabled = !isTtsPlayingOrLoading
+                                    ) {
+                                        Icon(Icons.Default.Search, contentDescription = stringResource(R.string.action_search))
+                                    }
+                                    PdfReaderTool.HIGHLIGHT_ALL -> TooltipIconButton(
+                                        text = if (showAllTextHighlights) stringResource(R.string.tooltip_highlights_off) else stringResource(R.string.tooltip_highlights),
+                                        description = if (showAllTextHighlights) stringResource(R.string.tooltip_highlights_off_desc) else stringResource(R.string.tooltip_highlights_desc),
+                                        onClick = onToggleHighlights
+                                    ) {
+                                        if (isHighlightingLoading) CircularProgressIndicator(Modifier.size(24.dp))
+                                        else Icon(painterResource(id = R.drawable.highlight_text), contentDescription = stringResource(R.string.content_desc_highlight_all_text), tint = if (showAllTextHighlights) MaterialTheme.colorScheme.primary else MaterialTheme.colorScheme.onSurfaceVariant)
+                                    }
+                                    PdfReaderTool.AI_FEATURES -> if (areReaderAiFeaturesEnabled(LocalContext.current)) {
+                                        TooltipIconButton(
+                                            text = stringResource(R.string.tooltip_ai),
+                                            description = stringResource(R.string.tooltip_ai_desc),
+                                            onClick = onShowAiHub
+                                        ) {
+                                            Icon(painterResource(id = R.drawable.ai), contentDescription = stringResource(R.string.tooltip_ai))
+                                        }
+                                    }
+                                    PdfReaderTool.EDIT_MODE -> TooltipIconButton(
+                                        text = if (isEditMode) stringResource(R.string.tooltip_edit_mode_exit) else stringResource(R.string.tooltip_edit_mode),
+                                        description = if (isEditMode) stringResource(R.string.tooltip_edit_mode_exit_desc) else stringResource(R.string.tooltip_edit_mode_desc),
+                                        onClick = onToggleEditMode
+                                    ) {
+                                        Icon(Icons.Default.Edit, contentDescription = stringResource(R.string.content_desc_toggle_editing_mode), tint = if (isEditMode) MaterialTheme.colorScheme.primary else MaterialTheme.colorScheme.onSurfaceVariant)
+                                    }
+                                    PdfReaderTool.TTS_CONTROLS -> TooltipIconButton(
+                                        text = if (isTtsSessionActive) stringResource(R.string.tooltip_tts_stop) else stringResource(R.string.tooltip_tts_start),
+                                        description = if (isTtsSessionActive) stringResource(R.string.tooltip_tts_stop_desc) else stringResource(R.string.tooltip_tts_start_desc),
+                                        onClick = onToggleTts
+                                    ) {
+                                        Icon(if (isTtsSessionActive) painterResource(id = R.drawable.close) else painterResource(id = R.drawable.text_to_speech), contentDescription = if (isTtsSessionActive) stringResource(R.string.content_desc_stop_tts) else stringResource(R.string.content_desc_start_tts), tint = if (isTtsSessionActive) MaterialTheme.colorScheme.primary else MaterialTheme.colorScheme.onSurfaceVariant)
+                                    }
+                                    else -> Unit
+                                }
                             }
-                        }
-
-                        if (!hiddenTools.contains(PdfReaderTool.LOCK_PANNING.name)) {
-                            TooltipIconButton(
-                                text = if (isScrollLocked) stringResource(R.string.tooltip_unlock_pan) else stringResource(R.string.tooltip_lock_pan),
-                                description = if (isScrollLocked) stringResource(R.string.tooltip_unlock_pan_desc) else stringResource(R.string.tooltip_lock_pan_desc),
-                                onClick = onToggleScrollLock
-                            ) {
-                                Icon(if (isScrollLocked) Icons.Default.Lock else Icons.Default.LockOpen, contentDescription = if (isScrollLocked) stringResource(R.string.tooltip_unlock_pan) else stringResource(R.string.tooltip_lock_pan), tint = MaterialTheme.colorScheme.onSurfaceVariant)
-                            }
-                        }
-
-                        if (!hiddenTools.contains(PdfReaderTool.DICTIONARY.name)) {
-                            TooltipIconButton(
-                                text = stringResource(R.string.tooltip_dictionary),
-                                description = stringResource(R.string.tooltip_dictionary_desc),
-                                onClick = onShowDictionarySettings
-                            ) {
-                                Icon(painterResource(id = R.drawable.dictionary), contentDescription = stringResource(R.string.content_desc_dictionary_settings), tint = MaterialTheme.colorScheme.onSurfaceVariant)
-                            }
-                        }
 
                         if (BuildConfig.DEBUG) {
                             TooltipIconButton(text = stringResource(R.string.tooltip_demo_annotations), onClick = onGenerateDemoAnnotations) {
@@ -197,14 +279,25 @@ internal fun PdfTopBar(
 
                         Box {
                             var showMoreMenu by remember { mutableStateOf(false) }
+                            var showHiddenToolsExpanded by remember { mutableStateOf(false) }
                             TooltipIconButton(
                                 text = stringResource(R.string.tooltip_more_options),
                                 description = stringResource(R.string.tooltip_more_options_desc),
-                                onClick = { showMoreMenu = true }) {
+                                onClick = {
+                                    showHiddenToolsExpanded = false
+                                    showMoreMenu = true
+                                }) {
                                 Icon(Icons.Default.MoreVert, contentDescription = stringResource(R.string.tooltip_more_options))
                             }
 
-                            DropdownMenu(expanded = showMoreMenu, onDismissRequest = { showMoreMenu = false }) {
+                            DropdownMenu(
+                                expanded = showMoreMenu,
+                                onDismissRequest = {
+                                    showHiddenToolsExpanded = false
+                                    showMoreMenu = false
+                                }
+                            ) {
+                                val hiddenToolbarTools = toolOrder.filter { it in pdfToolbarTools && hiddenTools.contains(it.name) }
                                 DropdownMenuItem(
                                     text = { Text(stringResource(R.string.title_customize_toolbar)) },
                                     onClick = { showMoreMenu = false; onShowCustomizeTools() },
@@ -212,6 +305,47 @@ internal fun PdfTopBar(
                                 )
                                 HorizontalDivider()
 
+                                if (hiddenToolbarTools.isNotEmpty()) {
+                                    DropdownMenuItem(
+                                        text = { Text("Hidden tools") },
+                                        onClick = { showHiddenToolsExpanded = !showHiddenToolsExpanded },
+                                        trailingIcon = {
+                                            Icon(
+                                                Icons.Default.ArrowDropDown,
+                                                contentDescription = null,
+                                                modifier = Modifier.rotate(if (showHiddenToolsExpanded) 180f else 0f)
+                                            )
+                                        }
+                                    )
+                                    if (showHiddenToolsExpanded) {
+                                        hiddenToolbarTools.forEach { tool ->
+                                            HiddenPdfToolMenuItem(
+                                                tool = tool,
+                                                isTtsPlayingOrLoading = isTtsPlayingOrLoading,
+                                                showAllTextHighlights = showAllTextHighlights,
+                                                isHighlightingLoading = isHighlightingLoading,
+                                                isEditMode = isEditMode,
+                                                isTtsSessionActive = isTtsSessionActive,
+                                                closeMenu = {
+                                                    showHiddenToolsExpanded = false
+                                                    showMoreMenu = false
+                                                },
+                                                onShowThemePanel = onShowThemePanel,
+                                                onToggleScrollLock = onToggleScrollLock,
+                                                onShowDictionarySettings = onShowDictionarySettings,
+                                                onShowSlider = onShowSlider,
+                                                onShowToc = onShowToc,
+                                                onSearchClick = onSearchClick,
+                                                onToggleHighlights = onToggleHighlights,
+                                                onShowAiHub = onShowAiHub,
+                                                onToggleEditMode = onToggleEditMode,
+                                                onToggleTts = onToggleTts
+                                            )
+                                        }
+                                    }
+                                    HorizontalDivider()
+                                }
+
                                 if (BuildConfig.IS_PRO && !hiddenTools.contains(PdfReaderTool.OCR_LANGUAGE.name)) {
                                     DropdownMenuItem(
                                         text = { Text(stringResource(R.string.menu_ocr_language)) },
@@ -402,6 +536,72 @@ internal fun PdfTopBar(
     }
 }
 
+@Composable
+private fun HiddenPdfToolMenuItem(
+    tool: PdfReaderTool,
+    isTtsPlayingOrLoading: Boolean,
+    showAllTextHighlights: Boolean,
+    isHighlightingLoading: Boolean,
+    isEditMode: Boolean,
+    isTtsSessionActive: Boolean,
+    closeMenu: () -> Unit,
+    onShowThemePanel: () -> Unit,
+    onToggleScrollLock: () -> Unit,
+    onShowDictionarySettings: () -> Unit,
+    onShowSlider: () -> Unit,
+    onShowToc: () -> Unit,
+    onSearchClick: () -> Unit,
+    onToggleHighlights: () -> Unit,
+    onShowAiHub: () -> Unit,
+    onToggleEditMode: () -> Unit,
+    onToggleTts: () -> Unit
+) {
+    val enabled = when (tool) {
+        PdfReaderTool.SLIDER,
+        PdfReaderTool.TOC,
+        PdfReaderTool.SEARCH -> !isTtsPlayingOrLoading
+        else -> true
+    }
+    DropdownMenuItem(
+        text = { Text(tool.title) },
+        enabled = enabled,
+        onClick = {
+            closeMenu()
+            when (tool) {
+                PdfReaderTool.THEME -> onShowThemePanel()
+                PdfReaderTool.LOCK_PANNING -> onToggleScrollLock()
+                PdfReaderTool.DICTIONARY -> onShowDictionarySettings()
+                PdfReaderTool.SLIDER -> onShowSlider()
+                PdfReaderTool.TOC -> onShowToc()
+                PdfReaderTool.SEARCH -> onSearchClick()
+                PdfReaderTool.HIGHLIGHT_ALL -> onToggleHighlights()
+                PdfReaderTool.AI_FEATURES -> onShowAiHub()
+                PdfReaderTool.EDIT_MODE -> onToggleEditMode()
+                PdfReaderTool.TTS_CONTROLS -> onToggleTts()
+                else -> Unit
+            }
+        },
+        leadingIcon = {
+            when (tool) {
+                PdfReaderTool.DICTIONARY -> Icon(painterResource(id = R.drawable.dictionary), contentDescription = null, modifier = Modifier.size(20.dp))
+                PdfReaderTool.THEME -> Icon(painterResource(id = R.drawable.palette), contentDescription = null, modifier = Modifier.size(20.dp))
+                PdfReaderTool.LOCK_PANNING -> Icon(Icons.Default.LockOpen, contentDescription = null, modifier = Modifier.size(20.dp))
+                PdfReaderTool.SLIDER -> Icon(painterResource(id = R.drawable.slider), contentDescription = null, modifier = Modifier.size(20.dp))
+                PdfReaderTool.TOC -> Icon(Icons.Default.Menu, contentDescription = null, modifier = Modifier.size(20.dp))
+                PdfReaderTool.SEARCH -> Icon(Icons.Default.Search, contentDescription = null, modifier = Modifier.size(20.dp))
+                PdfReaderTool.HIGHLIGHT_ALL -> {
+                    if (isHighlightingLoading) CircularProgressIndicator(Modifier.size(20.dp))
+                    else Icon(painterResource(id = R.drawable.highlight_text), contentDescription = null, modifier = Modifier.size(20.dp), tint = if (showAllTextHighlights) MaterialTheme.colorScheme.primary else MaterialTheme.colorScheme.onSurfaceVariant)
+                }
+                PdfReaderTool.AI_FEATURES -> Icon(painterResource(id = R.drawable.ai), contentDescription = null, modifier = Modifier.size(20.dp))
+                PdfReaderTool.EDIT_MODE -> Icon(Icons.Default.Edit, contentDescription = null, modifier = Modifier.size(20.dp), tint = if (isEditMode) MaterialTheme.colorScheme.primary else MaterialTheme.colorScheme.onSurfaceVariant)
+                PdfReaderTool.TTS_CONTROLS -> Icon(if (isTtsSessionActive) painterResource(id = R.drawable.close) else painterResource(id = R.drawable.text_to_speech), contentDescription = null, modifier = Modifier.size(20.dp), tint = if (isTtsSessionActive) MaterialTheme.colorScheme.primary else MaterialTheme.colorScheme.onSurfaceVariant)
+                else -> Icon(Icons.Default.MoreVert, contentDescription = null, modifier = Modifier.size(20.dp))
+            }
+        }
+    )
+}
+
 @Composable
 fun ReflowProgressOverlay(
     modifier: Modifier = Modifier,
@@ -447,6 +647,89 @@ fun ReflowProgressOverlay(
     }
 }
 
+@Composable
+fun PdfJumpHistoryBar(
+    modifier: Modifier = Modifier,
+    showStandardBars: Boolean,
+    searchStateActive: Boolean,
+    backPage: Int?,
+    forwardPage: Int?,
+    onBack: () -> Unit,
+    onForward: () -> Unit,
+    onClear: () -> Unit
+) {
+    AnimatedVisibility(
+        visible = showStandardBars && !searchStateActive && (backPage != null || forwardPage != null),
+        enter = slideInVertically(animationSpec = tween(200)) { fullHeight -> fullHeight } + fadeIn(animationSpec = tween(200)),
+        exit = slideOutVertically(animationSpec = tween(200)) { fullHeight -> fullHeight } + fadeOut(animationSpec = tween(200)),
+        modifier = modifier
+    ) {
+        Surface(
+            modifier = Modifier.fillMaxWidth(),
+            color = MaterialTheme.colorScheme.surfaceContainer,
+            tonalElevation = 3.dp
+        ) {
+            Row(
+                modifier = Modifier
+                    .fillMaxWidth()
+                    .height(40.dp)
+                    .padding(horizontal = 8.dp),
+                verticalAlignment = Alignment.CenterVertically,
+                horizontalArrangement = Arrangement.SpaceBetween
+            ) {
+                TextButton(
+                    onClick = onBack,
+                    enabled = backPage != null,
+                    modifier = Modifier.weight(1f)
+                ) {
+                    Icon(
+                        Icons.AutoMirrored.Filled.ArrowBack,
+                        contentDescription = stringResource(R.string.content_desc_jump_back),
+                        modifier = Modifier.size(16.dp)
+                    )
+                    Spacer(Modifier.width(4.dp))
+                    Text(
+                        text = backPage?.let { stringResource(R.string.pdf_page_short, it + 1) } ?: "",
+                        maxLines = 1,
+                        overflow = TextOverflow.Ellipsis
+                    )
+                }
+
+                TextButton(
+                    onClick = onClear,
+                    modifier = Modifier.weight(1f)
+                ) {
+                    Icon(
+                        Icons.Default.Close,
+                        contentDescription = stringResource(R.string.action_clear),
+                        modifier = Modifier.size(16.dp)
+                    )
+                    Spacer(Modifier.width(4.dp))
+                    Text(stringResource(R.string.action_clear), maxLines = 1)
+                }
+
+                TextButton(
+                    onClick = onForward,
+                    enabled = forwardPage != null,
+                    modifier = Modifier.weight(1f)
+                ) {
+                    Text(
+                        text = forwardPage?.let { stringResource(R.string.pdf_page_short, it + 1) } ?: "",
+                        maxLines = 1,
+                        overflow = TextOverflow.Ellipsis
+                    )
+                    Spacer(Modifier.width(4.dp))
+                    Icon(
+                        Icons.AutoMirrored.Filled.ArrowForward,
+                        contentDescription = stringResource(R.string.content_desc_jump_forward),
+                        modifier = Modifier.size(16.dp)
+                    )
+                }
+            }
+        }
+    }
+}
+
 @Composable
 fun PdfBottomBar(
     modifier: Modifier = Modifier,
@@ -455,14 +738,17 @@ fun PdfBottomBar(
     systemUiMode: SystemUiMode,
     navBarHeightDp: Dp,
     hiddenTools: Set<String>,
+    toolOrder: List<PdfReaderTool>,
+    bottomTools: Set<String>,
     isTtsPlayingOrLoading: Boolean,
     showAllTextHighlights: Boolean,
     isHighlightingLoading: Boolean,
     isEditMode: Boolean,
     isTtsSessionActive: Boolean,
     ttsErrorMessage: String?,
-    jumpBackPage: Int?,
-    onJumpBack: () -> Unit,
+    onShowThemePanel: () -> Unit,
+    onToggleScrollLock: () -> Unit,
+    onShowDictionarySettings: () -> Unit,
     onShowSlider: () -> Unit,
     onShowToc: () -> Unit,
     onSearchClick: () -> Unit,
@@ -490,106 +776,91 @@ fun PdfBottomBar(
                 verticalAlignment = Alignment.CenterVertically,
                 horizontalArrangement = Arrangement.SpaceEvenly
             ) {
-                if (jumpBackPage != null) {
-                    TooltipIconButton(
-                        text = stringResource(R.string.action_jump_back_to_page, jumpBackPage + 1),
-                        description = stringResource(R.string.desc_return_to_previous_page),
-                        onClick = onJumpBack
-                    ) {
-                        Column(
-                            horizontalAlignment = Alignment.CenterHorizontally,
-                            verticalArrangement = Arrangement.Center
-                        ) {
-                            Icon(
-                                Icons.AutoMirrored.Filled.Undo,
-                                contentDescription = stringResource(R.string.content_desc_jump_back),
-                                tint = MaterialTheme.colorScheme.primary,
-                                modifier = Modifier.size(16.dp)
-                            )
-                            Text(
-                                text = "${jumpBackPage + 1}",
-                                fontSize = 10.sp,
-                                lineHeight = 10.sp,
-                                fontWeight = FontWeight.Bold,
-                                color = MaterialTheme.colorScheme.primary
-                            )
+                toolOrder
+                    .filter { it in pdfToolbarTools && bottomTools.contains(it.name) && !hiddenTools.contains(it.name) }
+                    .forEach { tool ->
+                        when (tool) {
+                            PdfReaderTool.THEME -> TooltipIconButton(
+                                text = stringResource(R.string.tooltip_theme),
+                                description = stringResource(R.string.tooltip_theme_desc),
+                                onClick = onShowThemePanel
+                            ) {
+                                Icon(painterResource(id = R.drawable.palette), contentDescription = stringResource(R.string.tooltip_theme_desc), tint = MaterialTheme.colorScheme.onSurfaceVariant)
+                            }
+                            PdfReaderTool.LOCK_PANNING -> TooltipIconButton(
+                                text = stringResource(R.string.tooltip_lock_pan),
+                                description = stringResource(R.string.tooltip_lock_pan_desc),
+                                onClick = onToggleScrollLock
+                            ) {
+                                Icon(Icons.Default.LockOpen, contentDescription = stringResource(R.string.tooltip_lock_pan), tint = MaterialTheme.colorScheme.onSurfaceVariant)
+                            }
+                            PdfReaderTool.DICTIONARY -> TooltipIconButton(
+                                text = stringResource(R.string.tooltip_dictionary),
+                                description = stringResource(R.string.tooltip_dictionary_desc),
+                                onClick = onShowDictionarySettings
+                            ) {
+                                Icon(painterResource(id = R.drawable.dictionary), contentDescription = stringResource(R.string.content_desc_dictionary_settings), tint = MaterialTheme.colorScheme.onSurfaceVariant)
+                            }
+                            PdfReaderTool.SLIDER -> TooltipIconButton(
+                                text = stringResource(R.string.tooltip_slider),
+                                description = stringResource(R.string.tooltip_slider_desc),
+                                onClick = onShowSlider,
+                                enabled = !isTtsPlayingOrLoading
+                            ) {
+                                Icon(painterResource(id = R.drawable.slider), contentDescription = stringResource(R.string.content_desc_navigate_slider))
+                            }
+                            PdfReaderTool.TOC -> TooltipIconButton(
+                                text = stringResource(R.string.tooltip_toc),
+                                description = stringResource(R.string.tooltip_toc_desc),
+                                onClick = onShowToc,
+                                enabled = !isTtsPlayingOrLoading,
+                                modifier = Modifier.testTag("TocButton")
+                            ) {
+                                Icon(Icons.Default.Menu, contentDescription = stringResource(R.string.content_desc_table_of_contents))
+                            }
+                            PdfReaderTool.SEARCH -> TooltipIconButton(
+                                text = stringResource(R.string.tooltip_search),
+                                description = stringResource(R.string.tooltip_search_desc),
+                                onClick = onSearchClick,
+                                enabled = !isTtsPlayingOrLoading,
+                                modifier = Modifier.testTag("SearchButton")
+                            ) {
+                                Icon(Icons.Default.Search, contentDescription = stringResource(R.string.action_search))
+                            }
+                            PdfReaderTool.HIGHLIGHT_ALL -> TooltipIconButton(
+                                text = if (showAllTextHighlights) stringResource(R.string.tooltip_highlights_off) else stringResource(R.string.tooltip_highlights),
+                                description = if (showAllTextHighlights) stringResource(R.string.tooltip_highlights_off_desc) else stringResource(R.string.tooltip_highlights_desc),
+                                onClick = onToggleHighlights
+                            ) {
+                                if (isHighlightingLoading) CircularProgressIndicator(Modifier.size(24.dp))
+                                else Icon(painterResource(id = R.drawable.highlight_text), contentDescription = stringResource(R.string.content_desc_highlight_all_text), tint = if (showAllTextHighlights) MaterialTheme.colorScheme.primary else MaterialTheme.colorScheme.onSurfaceVariant)
+                            }
+                            PdfReaderTool.AI_FEATURES -> if (areReaderAiFeaturesEnabled(LocalContext.current)) {
+                                TooltipIconButton(
+                                    text = stringResource(R.string.tooltip_ai),
+                                    description = stringResource(R.string.tooltip_ai_desc),
+                                    onClick = onShowAiHub
+                                ) {
+                                    Icon(painterResource(id = R.drawable.ai), contentDescription = stringResource(R.string.tooltip_ai))
+                                }
+                            }
+                            PdfReaderTool.EDIT_MODE -> TooltipIconButton(
+                                text = if (isEditMode) stringResource(R.string.tooltip_edit_mode_exit) else stringResource(R.string.tooltip_edit_mode),
+                                description = if (isEditMode) stringResource(R.string.tooltip_edit_mode_exit_desc) else stringResource(R.string.tooltip_edit_mode_desc),
+                                onClick = onToggleEditMode
+                            ) {
+                                Icon(Icons.Default.Edit, contentDescription = stringResource(R.string.content_desc_toggle_editing_mode), tint = if (isEditMode) MaterialTheme.colorScheme.primary else MaterialTheme.colorScheme.onSurfaceVariant)
+                            }
+                            PdfReaderTool.TTS_CONTROLS -> TooltipIconButton(
+                                text = if (isTtsSessionActive) stringResource(R.string.tooltip_tts_stop) else stringResource(R.string.tooltip_tts_start),
+                                description = if (isTtsSessionActive) stringResource(R.string.tooltip_tts_stop_desc) else stringResource(R.string.tooltip_tts_start_desc),
+                                onClick = onToggleTts
+                            ) {
+                                Icon(if (isTtsSessionActive) painterResource(id = R.drawable.close) else painterResource(id = R.drawable.text_to_speech), contentDescription = if (isTtsSessionActive) stringResource(R.string.content_desc_stop_tts) else stringResource(R.string.content_desc_start_tts), tint = if (isTtsSessionActive) MaterialTheme.colorScheme.primary else MaterialTheme.colorScheme.onSurfaceVariant)
+                            }
+                            else -> Unit
                         }
                     }
-                }
-
-                if (!hiddenTools.contains(PdfReaderTool.SLIDER.name)) {
-                    TooltipIconButton(
-                        text = stringResource(R.string.tooltip_slider),
-                        description = stringResource(R.string.tooltip_slider_desc),
-                        onClick = onShowSlider,
-                        enabled = !isTtsPlayingOrLoading
-                    ) {
-                        Icon(painterResource(id = R.drawable.slider), contentDescription = stringResource(R.string.content_desc_navigate_slider))
-                    }
-                }
-                if (!hiddenTools.contains(PdfReaderTool.TOC.name)) {
-                    TooltipIconButton(
-                        text = stringResource(R.string.tooltip_toc),
-                        description = stringResource(R.string.tooltip_toc_desc),
-                        onClick = onShowToc,
-                        enabled = !isTtsPlayingOrLoading,
-                        modifier = Modifier.testTag("TocButton")
-                    ) {
-                        Icon(Icons.Default.Menu, contentDescription = stringResource(R.string.content_desc_table_of_contents))
-                    }
-                }
-
-                if (!hiddenTools.contains(PdfReaderTool.SEARCH.name)) {
-                    TooltipIconButton(
-                        text = stringResource(R.string.tooltip_search),
-                        description = stringResource(R.string.tooltip_search_desc),
-                        onClick = onSearchClick,
-                        enabled = !isTtsPlayingOrLoading,
-                        modifier = Modifier.testTag("SearchButton")
-                    ) {
-                        Icon(Icons.Default.Search, contentDescription = stringResource(R.string.action_search))
-                    }
-                }
-                if (!hiddenTools.contains(PdfReaderTool.HIGHLIGHT_ALL.name)) {
-                    TooltipIconButton(
-                        text = if (showAllTextHighlights) stringResource(R.string.tooltip_highlights_off) else stringResource(R.string.tooltip_highlights),
-                        description = if (showAllTextHighlights) stringResource(R.string.tooltip_highlights_off_desc) else stringResource(R.string.tooltip_highlights_desc),
-                        onClick = onToggleHighlights
-                    ) {
-                        if (isHighlightingLoading) CircularProgressIndicator(Modifier.size(24.dp))
-                        else Icon(painterResource(id = R.drawable.highlight_text), contentDescription = stringResource(R.string.content_desc_highlight_all_text), tint = if (showAllTextHighlights) MaterialTheme.colorScheme.primary else MaterialTheme.colorScheme.onSurfaceVariant)
-                    }
-                }
-
-                if (BuildConfig.FLAVOR != "oss" && !hiddenTools.contains(PdfReaderTool.AI_FEATURES.name)) {
-                    TooltipIconButton(
-                        text = stringResource(R.string.tooltip_ai),
-                        description = stringResource(R.string.tooltip_ai_desc),
-                        onClick = onShowAiHub
-                    ) {
-                        Icon(painterResource(id = R.drawable.ai), contentDescription = stringResource(R.string.tooltip_ai))
-                    }
-                }
-
-                if (!hiddenTools.contains(PdfReaderTool.EDIT_MODE.name)) {
-                    TooltipIconButton(
-                        text = if (isEditMode) stringResource(R.string.tooltip_edit_mode_exit) else stringResource(R.string.tooltip_edit_mode),
-                        description = if (isEditMode) stringResource(R.string.tooltip_edit_mode_exit_desc) else stringResource(R.string.tooltip_edit_mode_desc),
-                        onClick = onToggleEditMode
-                    ) {
-                        Icon(Icons.Default.Edit, contentDescription = stringResource(R.string.content_desc_toggle_editing_mode), tint = if (isEditMode) MaterialTheme.colorScheme.primary else MaterialTheme.colorScheme.onSurfaceVariant)
-                    }
-                }
-
-                if (!hiddenTools.contains(PdfReaderTool.TTS_CONTROLS.name)) {
-                    TooltipIconButton(
-                        text = if (isTtsSessionActive) stringResource(R.string.tooltip_tts_stop) else stringResource(R.string.tooltip_tts_start),
-                        description = if (isTtsSessionActive) stringResource(R.string.tooltip_tts_stop_desc) else stringResource(R.string.tooltip_tts_start_desc),
-                        onClick = onToggleTts
-                    ) {
-                        Icon(if (isTtsSessionActive) painterResource(id = R.drawable.close) else painterResource(id = R.drawable.text_to_speech), contentDescription = if (isTtsSessionActive) stringResource(R.string.content_desc_stop_tts) else stringResource(R.string.content_desc_start_tts), tint = if (isTtsSessionActive) MaterialTheme.colorScheme.primary else MaterialTheme.colorScheme.onSurfaceVariant)
-                    }
-                }
 
                 if (BuildConfig.FLAVOR != "oss") {
                     TooltipIconButton(

app/src/main/java/com/aryan/reader/pdf/PdfVerticalReader.kt

@@ -193,6 +193,7 @@ internal fun PdfVerticalReader(
     state: VerticalPdfReaderState,
     pdfDocument: StableHolder<ReaderDocument>,
     activeTheme: com.aryan.reader.ReaderTheme,
+    activeTextureAlpha: Float = 0.55f,
     excludeImages: Boolean = false,
     totalPages: Int,
     virtualPages: List<VirtualPage> = emptyList(),
@@ -988,7 +989,7 @@ internal fun PdfVerticalReader(
                 }
 
                 val buttons = currentEvent.buttons
-                Timber.tag("StylusEraserDiagnostic").d(
+                Timber.tag("StylusDebug").d(
                     "VerticalReader | Type: ${down.type} | isPrimary: ${buttons.isPrimaryPressed} | isSecondary: ${buttons.isSecondaryPressed} | isTertiary: ${buttons.isTertiaryPressed} | buttonsString: $buttons"
                 )
 
@@ -1688,6 +1689,7 @@ internal fun PdfVerticalReader(
                                     virtualPage = virtualPage,
                                     totalPages = totalPages,
                                     activeTheme = activeTheme,
+                                    activeTextureAlpha = activeTextureAlpha,
                                     excludeImages = excludeImages,
                                     externalScale = highResScale,
                                     onScaleChanged = {},

app/src/main/java/com/aryan/reader/pdf/PdfiumEngineProvider.kt

@@ -0,0 +1,120 @@
+package com.aryan.reader.pdf
+
+import com.aryan.reader.shared.pdf.PdfiumBridge
+import kotlinx.coroutines.runBlocking
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
+
+internal object PdfiumEngineProvider {
+    private val pdfiumMutex = Mutex()
+
+    val bridge: PdfiumBridge
+        get() = AndroidPdfiumBridge
+
+    val lock: Any = this
+
+    suspend fun <T> withPdfium(block: suspend () -> T): T =
+        pdfiumMutex.withLock { block() }
+
+    fun <T> withPdfiumBlocking(block: () -> T): T =
+        runBlocking {
+            pdfiumMutex.withLock { block() }
+        }
+}
+
+private object AndroidPdfiumBridge : PdfiumBridge {
+    override fun getFontSize(textPagePtr: Long, index: Int): Double =
+        PdfiumEngineProvider.withPdfiumBlocking {
+            NativePdfiumBridge.getFontSize(textPagePtr, index)
+        }
+
+    override fun getFontWeight(textPagePtr: Long, index: Int): Int =
+        PdfiumEngineProvider.withPdfiumBlocking {
+            NativePdfiumBridge.getFontWeight(textPagePtr, index)
+        }
+
+    override fun getPageFontSizes(textPagePtr: Long, count: Int): FloatArray? =
+        PdfiumEngineProvider.withPdfiumBlocking {
+            NativePdfiumBridge.getPageFontSizes(textPagePtr, count)
+        }
+
+    override fun getPageFontWeights(textPagePtr: Long, count: Int): IntArray? =
+        PdfiumEngineProvider.withPdfiumBlocking {
+            NativePdfiumBridge.getPageFontWeights(textPagePtr, count)
+        }
+
+    override fun getPageFontFlags(textPagePtr: Long, count: Int): IntArray? =
+        PdfiumEngineProvider.withPdfiumBlocking {
+            NativePdfiumBridge.getPageFontFlags(textPagePtr, count)
+        }
+
+    override fun getPageCharBoxes(textPagePtr: Long, count: Int): FloatArray? =
+        PdfiumEngineProvider.withPdfiumBlocking {
+            NativePdfiumBridge.getPageCharBoxes(textPagePtr, count)
+        }
+
+    override fun getAnnotCount(pagePtr: Long): Int =
+        PdfiumEngineProvider.withPdfiumBlocking {
+            NativePdfiumBridge.getAnnotCount(pagePtr)
+        }
+
+    override fun getAnnotSubtype(pagePtr: Long, index: Int): Int =
+        PdfiumEngineProvider.withPdfiumBlocking {
+            NativePdfiumBridge.getAnnotSubtype(pagePtr, index)
+        }
+
+    override fun getAnnotRect(pagePtr: Long, index: Int): FloatArray? =
+        PdfiumEngineProvider.withPdfiumBlocking {
+            NativePdfiumBridge.getAnnotRect(pagePtr, index)
+        }
+
+    override fun getAnnotString(pagePtr: Long, index: Int, key: String): String? =
+        PdfiumEngineProvider.withPdfiumBlocking {
+            NativePdfiumBridge.getAnnotString(pagePtr, index, key)
+        }
+
+    override fun getPageObjectCount(pagePtr: Long): Int =
+        PdfiumEngineProvider.withPdfiumBlocking {
+            NativePdfiumBridge.getPageObjectCount(pagePtr)
+        }
+
+    override fun getPageObjectType(pagePtr: Long, index: Int): Int =
+        PdfiumEngineProvider.withPdfiumBlocking {
+            NativePdfiumBridge.getPageObjectType(pagePtr, index)
+        }
+
+    override fun getPageObjectBoundingBox(pagePtr: Long, index: Int, outRect: FloatArray): Boolean =
+        PdfiumEngineProvider.withPdfiumBlocking {
+            NativePdfiumBridge.getPageObjectBoundingBox(pagePtr, index, outRect)
+        }
+
+    override fun extractImagePixels(pagePtr: Long, index: Int, dimens: IntArray): IntArray? =
+        PdfiumEngineProvider.withPdfiumBlocking {
+            NativePdfiumBridge.extractImagePixels(pagePtr, index, dimens)
+        }
+
+    override fun performClick(pagePtr: Long, x: Double, y: Double): Boolean =
+        PdfiumEngineProvider.withPdfiumBlocking {
+            NativePdfiumBridge.performClick(pagePtr, x, y)
+        }
+
+    override fun getLinkInfoAtPoint(docPtr: Long, pagePtr: Long, x: Double, y: Double): String? =
+        PdfiumEngineProvider.withPdfiumBlocking {
+            NativePdfiumBridge.getLinkInfoAtPoint(docPtr, pagePtr, x, y)
+        }
+
+    override fun getAnnotSubtypeAtPoint(pagePtr: Long, x: Double, y: Double): Int =
+        PdfiumEngineProvider.withPdfiumBlocking {
+            NativePdfiumBridge.getAnnotSubtypeAtPoint(pagePtr, x, y)
+        }
+
+    override fun getAnnotRectAtPoint(pagePtr: Long, x: Double, y: Double): FloatArray? =
+        PdfiumEngineProvider.withPdfiumBlocking {
+            NativePdfiumBridge.getAnnotRectAtPoint(pagePtr, x, y)
+        }
+
+    override fun checkActionSupport(): Boolean =
+        PdfiumEngineProvider.withPdfiumBlocking {
+            NativePdfiumBridge.checkActionSupport()
+        }
+}

app/src/main/java/com/aryan/reader/pdf/UniversalDocument.kt

@@ -28,6 +28,7 @@ import me.zhanghai.android.libarchive.ArchiveException
 import okhttp3.Request
 import timber.log.Timber
 import java.util.UUID
+import java.util.concurrent.atomic.AtomicBoolean
 import java.util.zip.ZipFile
 import androidx.core.graphics.createBitmap
 
@@ -88,42 +89,97 @@ object DocumentFactory {
             ArchiveDocumentWrapper(cacheFile)
         } else {
             val pfd = context.contentResolver.openFileDescriptor(uri, "r") ?: throw Exception("Failed to open PDF")
-            PdfDocumentWrapper(pdfiumCore.newDocument(pfd, password))
+            PdfDocumentWrapper(PdfiumEngineProvider.withPdfium { pdfiumCore.newDocument(pfd, password) })
         }
     }
 }
 
 // ================= PDF IMPLEMENTATION =================
 
+private inline fun closePdfiumResource(tag: String, closeBlock: () -> Unit) {
+    try {
+        closeBlock()
+    } catch (e: IllegalStateException) {
+        if (e.message == "Already closed") {
+            Timber.tag(tag).d(e, "Ignoring duplicate Pdfium close")
+        } else {
+            throw e
+        }
+    }
+}
+
 class PdfDocumentWrapper(val pdfDocument: PdfDocumentKt) : ReaderDocument {
-    override suspend fun getPageCount() = pdfDocument.getPageCount()
+    private val isClosed = AtomicBoolean(false)
+
+    override suspend fun getPageCount() = PdfiumEngineProvider.withPdfium {
+        pdfDocument.getPageCount()
+    }
+
     override suspend fun openPage(pageIndex: Int): ReaderPage? {
-        val page = pdfDocument.openPage(pageIndex) ?: return null
+        if (isClosed.get()) return null
+        val page = PdfiumEngineProvider.withPdfium {
+            if (isClosed.get()) null else pdfDocument.openPage(pageIndex)
+        } ?: return null
         return PdfPageWrapper(page)
     }
-    override suspend fun getTableOfContents() = pdfDocument.getFixedTableOfContents()
-    override fun close() { pdfDocument.close() }
+
+    override suspend fun getTableOfContents() = PdfiumEngineProvider.withPdfium {
+        pdfDocument.getFixedTableOfContents()
+    }
+
+    override fun close() {
+        if (!isClosed.compareAndSet(false, true)) return
+        PdfiumEngineProvider.withPdfiumBlocking {
+            closePdfiumResource("PdfDocumentWrapper") { pdfDocument.close() }
+        }
+    }
 }
 
 class PdfPageWrapper(val pdfPage: PdfPageKt) : ReaderPage {
-    override suspend fun getPageWidthPoint() = pdfPage.getPageWidthPoint()
-    override suspend fun getPageHeightPoint() = pdfPage.getPageHeightPoint()
-    override suspend fun getPageRotation() = pdfPage.getPageRotation()
+    private val isClosed = AtomicBoolean(false)
+
+    override suspend fun getPageWidthPoint() = PdfiumEngineProvider.withPdfium {
+        if (isClosed.get()) 0 else pdfPage.getPageWidthPoint()
+    }
+
+    override suspend fun getPageHeightPoint() = PdfiumEngineProvider.withPdfium {
+        if (isClosed.get()) 0 else pdfPage.getPageHeightPoint()
+    }
+
+    override suspend fun getPageRotation() = PdfiumEngineProvider.withPdfium {
+        if (isClosed.get()) 0 else pdfPage.getPageRotation()
+    }
 
     override suspend fun renderPageBitmap(bitmap: Bitmap, startX: Int, startY: Int, drawSizeX: Int, drawSizeY: Int, renderAnnot: Boolean) {
-        pdfPage.renderPageBitmap(bitmap, startX, startY, drawSizeX, drawSizeY, renderAnnot)
+        PdfiumEngineProvider.withPdfium {
+            if (!isClosed.get()) {
+                pdfPage.renderPageBitmap(bitmap, startX, startY, drawSizeX, drawSizeY, renderAnnot)
+            }
+        }
     }
 
     override suspend fun mapRectToDevice(startX: Int, startY: Int, sizeX: Int, sizeY: Int, rotate: Int, coords: RectF) =
-        pdfPage.mapRectToDevice(startX, startY, sizeX, sizeY, rotate, coords)
+        PdfiumEngineProvider.withPdfium {
+            if (isClosed.get()) Rect() else pdfPage.mapRectToDevice(startX, startY, sizeX, sizeY, rotate, coords)
+        }
 
     override suspend fun mapDeviceCoordsToPage(startX: Int, startY: Int, sizeX: Int, sizeY: Int, rotate: Int, deviceX: Int, deviceY: Int) =
-        pdfPage.mapDeviceCoordsToPage(startX, startY, sizeX, sizeY, rotate, deviceX, deviceY)
+        PdfiumEngineProvider.withPdfium {
+            if (isClosed.get()) PointF() else pdfPage.mapDeviceCoordsToPage(startX, startY, sizeX, sizeY, rotate, deviceX, deviceY)
+        }
 
-    override suspend fun openTextPage(): ReaderTextPage = PdfTextPageWrapper(pdfPage.openTextPage())
+    override suspend fun openTextPage(): ReaderTextPage = PdfiumEngineProvider.withPdfium {
+        if (isClosed.get()) DummyTextPage() else PdfTextPageWrapper(pdfPage.openTextPage())
+    }
 
     override suspend fun getLinks(): List<ReaderLink> {
-        return pdfPage.getPageLinks().map { ReaderLink(it.uri, it.destPageIdx, it.bounds) }
+        return PdfiumEngineProvider.withPdfium {
+            if (isClosed.get()) {
+                emptyList()
+            } else {
+                pdfPage.getPageLinks().map { ReaderLink(it.uri, it.destPageIdx, it.bounds) }
+            }
+        }
     }
 
     override fun getNativePointer(): Long {
@@ -159,29 +215,80 @@ class PdfPageWrapper(val pdfPage: PdfPageKt) : ReaderPage {
         return 0L
     }
 
-    override fun close() { pdfPage.close() }
+    override fun close() {
+        if (!isClosed.compareAndSet(false, true)) return
+        PdfiumEngineProvider.withPdfiumBlocking {
+            closePdfiumResource("PdfPageWrapper") { pdfPage.close() }
+        }
+    }
 }
 
 class PdfTextPageWrapper(private val textPage: PdfTextPageKt) : ReaderTextPage {
-    override suspend fun textPageCountChars() = textPage.textPageCountChars()
-    override suspend fun textPageGetText(startIndex: Int, count: Int) = textPage.textPageGetText(startIndex, count)
-    override suspend fun textPageGetRectsForRanges(ranges: IntArray) = textPage.textPageGetRectsForRanges(ranges)?.map { ReaderTextRect(it.rect) }
-    override suspend fun textPageGetCharIndexAtPos(x: Double, y: Double, xTolerance: Double, yTolerance: Double) = textPage.textPageGetCharIndexAtPos(x, y, xTolerance, yTolerance)
-    override suspend fun textPageGetCharBox(index: Int) = textPage.textPageGetCharBox(index)
-    override suspend fun textPageGetUnicode(index: Int): Int {
-        return textPage.textPageGetUnicode(index).code
+    private val isClosed = AtomicBoolean(false)
+
+    override suspend fun textPageCountChars() = PdfiumEngineProvider.withPdfium {
+        if (isClosed.get()) 0 else textPage.textPageCountChars()
     }
-    override suspend fun loadWebLink(): ReaderWebLinks? {
-        val links = textPage.loadWebLink() ?: return null
-        return object : ReaderWebLinks {
-            override suspend fun countWebLinks() = links.countWebLinks()
-            override suspend fun getURL(linkIndex: Int, maxLength: Int) = links.getURL(linkIndex, maxLength)
-            override suspend fun countRects(linkIndex: Int) = links.countRects(linkIndex)
-            override suspend fun getRect(linkIndex: Int, rectIndex: Int) = links.getRect(linkIndex, rectIndex)
-            override fun close() { links.close() }
+
+    override suspend fun textPageGetText(startIndex: Int, count: Int) = PdfiumEngineProvider.withPdfium {
+        if (isClosed.get()) null else textPage.textPageGetText(startIndex, count)
+    }
+
+    override suspend fun textPageGetRectsForRanges(ranges: IntArray) = PdfiumEngineProvider.withPdfium {
+        if (isClosed.get()) null else textPage.textPageGetRectsForRanges(ranges)?.map { ReaderTextRect(it.rect) }
+    }
+
+    override suspend fun textPageGetCharIndexAtPos(x: Double, y: Double, xTolerance: Double, yTolerance: Double) = PdfiumEngineProvider.withPdfium {
+        if (isClosed.get()) -1 else textPage.textPageGetCharIndexAtPos(x, y, xTolerance, yTolerance)
+    }
+
+    override suspend fun textPageGetCharBox(index: Int) = PdfiumEngineProvider.withPdfium {
+        if (isClosed.get()) null else textPage.textPageGetCharBox(index)
+    }
+
+    override suspend fun textPageGetUnicode(index: Int): Int {
+        return PdfiumEngineProvider.withPdfium {
+            if (isClosed.get()) 0 else textPage.textPageGetUnicode(index).code
+        }
+    }
+
+    override suspend fun loadWebLink(): ReaderWebLinks? {
+        val links = PdfiumEngineProvider.withPdfium {
+            if (isClosed.get()) null else textPage.loadWebLink()
+        } ?: return null
+        return object : ReaderWebLinks {
+            private val isClosed = AtomicBoolean(false)
+
+            override suspend fun countWebLinks() = PdfiumEngineProvider.withPdfium {
+                if (isClosed.get()) 0 else links.countWebLinks()
+            }
+
+            override suspend fun getURL(linkIndex: Int, maxLength: Int) = PdfiumEngineProvider.withPdfium {
+                if (isClosed.get()) null else links.getURL(linkIndex, maxLength)
+            }
+
+            override suspend fun countRects(linkIndex: Int) = PdfiumEngineProvider.withPdfium {
+                if (isClosed.get()) 0 else links.countRects(linkIndex)
+            }
+
+            override suspend fun getRect(linkIndex: Int, rectIndex: Int) = PdfiumEngineProvider.withPdfium {
+                if (isClosed.get()) RectF() else links.getRect(linkIndex, rectIndex)
+            }
+
+            override fun close() {
+                if (!isClosed.compareAndSet(false, true)) return
+                PdfiumEngineProvider.withPdfiumBlocking {
+                    closePdfiumResource("PdfWebLinksWrapper") { links.close() }
+                }
+            }
+        }
+    }
+    override fun close() {
+        if (!isClosed.compareAndSet(false, true)) return
+        PdfiumEngineProvider.withPdfiumBlocking {
+            closePdfiumResource("PdfTextPageWrapper") { textPage.close() }
         }
     }
-    override fun close() { textPage.close() }
 }
 
 // ================= CBZ, CBR, CB7 IMPLEMENTATION =================

app/src/main/java/com/aryan/reader/pdf/data/PdfTextRepository.kt

@@ -34,6 +34,7 @@ import androidx.paging.PagingConfig
 import androidx.paging.PagingData
 import androidx.paging.flatMap
 import com.aryan.reader.SearchResult
+import com.aryan.reader.pdf.PdfiumEngineProvider
 import androidx.compose.ui.text.AnnotatedString
 import androidx.compose.ui.text.SpanStyle
 import androidx.compose.ui.text.buildAnnotatedString
@@ -171,13 +172,15 @@ class PdfTextRepository(context: Context) {
             var ocrUsed = false
 
             try {
-                document.openPage(pageIndex)?.use { page ->
-                    page.openTextPage().use { textPage ->
-                        val count = textPage.textPageCountChars()
-                        if (count > 0) {
-                            val nativeText = textPage.textPageGetText(0, count)
-                            if (!nativeText.isNullOrBlank()) {
-                                text = nativeText
+                PdfiumEngineProvider.withPdfium {
+                    document.openPage(pageIndex)?.use { page ->
+                        page.openTextPage().use { textPage ->
+                            val count = textPage.textPageCountChars()
+                            if (count > 0) {
+                                val nativeText = textPage.textPageGetText(0, count)
+                                if (!nativeText.isNullOrBlank()) {
+                                    text = nativeText
+                                }
                             }
                         }
                     }
@@ -187,26 +190,35 @@ class PdfTextRepository(context: Context) {
             }
 
             if (text.isBlank()) {
+                var bitmap: android.graphics.Bitmap? = null
                 try {
-                    document.openPage(pageIndex)?.use { page ->
-                        val targetWidth = 1080
-                        val ptrWidth = page.getPageWidthPoint()
-                        val ptrHeight = page.getPageHeightPoint()
+                    PdfiumEngineProvider.withPdfium {
+                        document.openPage(pageIndex)?.use { page ->
+                            val targetWidth = 1080
+                            val ptrWidth = page.getPageWidthPoint()
+                            val ptrHeight = page.getPageHeightPoint()
 
-                        if (ptrWidth > 0 && ptrHeight > 0) {
-                            val aspectRatio = ptrWidth.toFloat() / ptrHeight.toFloat()
-                            val targetHeight = (targetWidth / aspectRatio).toInt().coerceAtLeast(1)
+                            if (ptrWidth > 0 && ptrHeight > 0) {
+                                val aspectRatio = ptrWidth.toFloat() / ptrHeight.toFloat()
+                                val targetHeight = (targetWidth / aspectRatio).toInt().coerceAtLeast(1)
 
-                            val bitmap = createBitmap(targetWidth, targetHeight)
-                            page.renderPageBitmap(bitmap, 0, 0, targetWidth, targetHeight, false)
-
-                            val visionText = OcrHelper.extractTextFromBitmap(bitmap, onOcrModelDownloading)
+                                bitmap = createBitmap(targetWidth, targetHeight)
+                                page.renderPageBitmap(bitmap!!, 0, 0, targetWidth, targetHeight, false)
+                            }
+                        }
+                    }
+                    bitmap?.let {
+                        try {
+                            val visionText = OcrHelper.extractTextFromBitmap(it, onOcrModelDownloading)
                             text = visionText?.text ?: ""
-                            bitmap.recycle()
                             ocrUsed = true
+                        } finally {
+                            it.recycle()
+                            bitmap = null
                         }
                     }
                 } catch (e: Exception) {
+                    bitmap?.recycle()
                     Timber.tag(TAG).e(e, "OCR failed for page $pageIndex")
                 }
             }
@@ -270,11 +282,13 @@ class PdfTextRepository(context: Context) {
     suspend fun hasNativeText(document: PdfDocumentKt, pageIndex: Int): Boolean {
         return withContext(Dispatchers.IO) {
             try {
-                document.openPage(pageIndex)?.use { page ->
-                    page.openTextPage().use { textPage ->
-                        textPage.textPageCountChars() > 0
-                    }
-                } ?: false
+                PdfiumEngineProvider.withPdfium {
+                    document.openPage(pageIndex)?.use { page ->
+                        page.openTextPage().use { textPage ->
+                            textPage.textPageCountChars() > 0
+                        }
+                    } ?: false
+                }
             } catch (_: Exception) {
                 false
             }

app/src/main/java/com/aryan/reader/tts/BaseTtsSynthesizer.kt

@@ -34,6 +34,7 @@ import java.io.File
 import java.util.Locale
 import java.util.UUID
 import java.util.concurrent.ConcurrentHashMap
+import kotlinx.coroutines.selects.select
 import kotlinx.coroutines.sync.Mutex
 import kotlinx.coroutines.sync.withLock
 import kotlinx.coroutines.suspendCancellableCoroutine
@@ -247,11 +248,16 @@ class BaseTtsSynthesizer(private val context: Context) {
 
                     try {
                         withTimeout(startTimeout) {
-                            startSignal.await()
+                            select {
+                                startSignal.onAwait { }
+                                resultDeferred.onAwait { }
+                            }
                         }
                     } catch (_: TimeoutCancellationException) {
-                        Timber.w("BaseTts: ZOMBIE DETECTED. onStart not received within ${startTimeout}ms.")
-                        throw ZombieEngineException()
+                        Timber.w(
+                            "BaseTts: onStart not received within ${startTimeout}ms for $utteranceId. " +
+                                "Continuing to wait for onDone because some engines omit or delay onStart for file synthesis."
+                        )
                     }
 
                     try {
@@ -296,5 +302,4 @@ class BaseTtsSynthesizer(private val context: Context) {
         Timber.d("TextToSpeech engine shut down.")
     }
 
-    private class ZombieEngineException : Exception("Engine failed to start")
 }

app/src/main/java/com/aryan/reader/tts/TtsController.kt

@@ -39,6 +39,7 @@ import androidx.media3.session.SessionToken
 import com.aryan.reader.BuildConfig
 import com.aryan.reader.epubreader.loadTtsPitch
 import com.aryan.reader.epubreader.loadTtsSpeechRate
+import com.aryan.reader.isByokCloudTtsAvailable
 import com.aryan.reader.tts.TtsPlaybackManager.TtsState
 import com.google.common.util.concurrent.ListenableFuture
 import com.google.common.util.concurrent.MoreExecutors
@@ -72,7 +73,7 @@ fun loadTtsMode(context: Context): TtsPlaybackManager.TtsMode {
     val savedModeName = prefs.getString("tts_mode", TtsPlaybackManager.TtsMode.BASE.name)
         ?: TtsPlaybackManager.TtsMode.BASE.name
 
-    val isCloudAllowed = BuildConfig.TTS_WORKER_URL.isNotBlank()
+    val isCloudAllowed = BuildConfig.TTS_WORKER_URL.isNotBlank() || isByokCloudTtsAvailable(context)
 
     return if (isCloudAllowed) {
         try {
@@ -105,8 +106,14 @@ class TtsController(context: Context) : Player.Listener {
     }
 
     fun connect() {
-        if (mediaController != null || controllerFuture != null) return
+        if (mediaController != null || controllerFuture != null) {
+            Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+                "TtsController.connect skipped. hasController=${mediaController != null}, hasFuture=${controllerFuture != null}"
+            )
+            return
+        }
 
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i("TtsController.connect building MediaController.")
         val sessionToken = SessionToken(context, ComponentName(context, TtsService::class.java))
         val future = MediaController.Builder(context, sessionToken).buildAsync()
         controllerFuture = future
@@ -129,10 +136,14 @@ class TtsController(context: Context) : Player.Listener {
 
                     mediaController?.addListener(this)
                     Timber.d("MediaController connected.")
+                    Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+                        "MediaController connected. playbackState=${controller.playbackState}, isPlaying=${controller.isPlaying}, mediaItems=${controller.mediaItemCount}, customLayout=${controller.customLayout.size}"
+                    )
                     updateStateFromController()
                     startPolling()
                 } catch (e: Exception) {
                     Timber.w("Failed to connect MediaController: ${e.message}")
+                    Timber.tag(TTS_NOTIFICATION_DIAG_TAG).e(e, "MediaController connection failed.")
                     if (controllerFuture == future) {
                         controllerFuture = null
                     }
@@ -158,15 +169,21 @@ class TtsController(context: Context) : Player.Listener {
         chapterTitle: String?,
         coverImageUri: String?,
         chapterIndex: Int? = null,
+        totalChapters: Int? = null,
+        continueSession: Boolean = false,
         ttsMode: TtsPlaybackManager.TtsMode,
         playbackSource: String = "READER",
         authToken: String? = null
     ) {
         if (chunks.isEmpty()) {
             Timber.w("TtsController: start called with empty chunks!")
+            Timber.tag(TTS_NOTIFICATION_DIAG_TAG).w("TtsController.start aborted because chunks is empty.")
             return
         }
         Timber.d("UI sending START command with mode: $ttsMode")
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+            "TtsController.start. hasController=${mediaController != null}, chunks=${chunks.size}, continueSession=$continueSession, source=$playbackSource, mode=$ttsMode, book='${bookTitle.take(60)}', chapter='${chapterTitle.orEmpty().take(60)}', chapterIndex=$chapterIndex, totalChapters=$totalChapters"
+        )
 
         val textList = ArrayList(chunks.map { it.text })
         val cfiList = ArrayList(chunks.map { it.sourceCfi })
@@ -181,6 +198,8 @@ class TtsController(context: Context) : Player.Listener {
             putString(KEY_CHAPTER_TITLE, chapterTitle)
             putString(KEY_COVER_IMAGE_URI, coverImageUri)
             chapterIndex?.let { putInt(KEY_CHAPTER_INDEX, it) }
+            totalChapters?.let { putInt(KEY_TOTAL_CHAPTERS, it) }
+            putBoolean(KEY_CONTINUE_SESSION, continueSession)
             putString(KEY_TTS_MODE, ttsMode.name)
             putString(KEY_PLAYBACK_SOURCE, playbackSource)
             putString(KEY_AUTH_TOKEN, authToken)
@@ -188,7 +207,15 @@ class TtsController(context: Context) : Player.Listener {
             putFloat("playback_pitch", loadTtsPitch(context))
         }
         Timber.tag("TTS_CLOUD_DIAG").d("TtsController sending START. Mode: $ttsMode, Chunks: ${chunks.size}, Token present: ${!authToken.isNullOrBlank()}")
-        mediaController?.sendCustomCommand(START_TTS_COMMAND, args)
+        val controller = mediaController
+        if (controller == null) {
+            Timber.tag(TTS_NOTIFICATION_DIAG_TAG).e("Cannot send START command because MediaController is null.")
+        } else {
+            val result = controller.sendCustomCommand(START_TTS_COMMAND, args)
+            Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+                "START command sent. playbackState=${controller.playbackState}, isPlaying=${controller.isPlaying}, mediaItems=${controller.mediaItemCount}, resultDone=${result.isDone}"
+            )
+        }
     }
 
     fun pause() {
@@ -240,6 +267,9 @@ class TtsController(context: Context) : Player.Listener {
     }
 
     override fun onEvents(player: Player, events: Player.Events) {
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+            "Controller onEvents. playbackState=${player.playbackState}, isPlaying=${player.isPlaying}, playWhenReady=${player.playWhenReady}, mediaItems=${player.mediaItemCount}, currentIndex=${player.currentMediaItemIndex}, events=$events"
+        )
         updateStateFromController()
     }
 
@@ -247,7 +277,9 @@ class TtsController(context: Context) : Player.Listener {
         mediaController?.let { controller ->
             val customState = controller.customLayout.firstOrNull()?.extras ?: Bundle.EMPTY
             val currentMediaItem = controller.currentMediaItem
-            val currentTextFromMediaItem = currentMediaItem?.mediaMetadata?.subtitle?.toString()
+            val mediaItemExtras = currentMediaItem?.mediaMetadata?.extras
+            val currentTextFromMediaItem = mediaItemExtras?.getString("ttsText")
+                ?: currentMediaItem?.mediaMetadata?.subtitle?.toString()
             val isPlaybackActive = controller.isPlaying || controller.playbackState == Player.STATE_READY || controller.playbackState == Player.STATE_BUFFERING
             val serviceSpeaker = customState.getString("speakerId", _ttsState.value.speakerId)
             val sessionEndedByStop = customState.getBoolean("sessionEndedByStop", false)
@@ -255,9 +287,13 @@ class TtsController(context: Context) : Player.Listener {
             val sessionFinished = customState.getBoolean("sessionFinished", false)
             val playbackSource = customState.getString("playbackSource")
             val serviceBookTitle = customState.getString("bookTitle")
+            val serviceChapterTitle = customState.getString("chapterTitle")
             val serviceChapterIndex = customState.getInt("chapterIndex", -1).takeIf { it >= 0 }
+            val serviceTotalChapters = customState.getInt("totalChapters", -1).takeIf { it > 0 }
+            val serviceCurrentChunkIndex = customState.getInt("currentChunkIndex", -1)
+            val serviceTotalChunks = customState.getInt("totalChunks", 0)
+            val serviceBookProgressPercent = customState.getInt("bookProgressPercent", -1).takeIf { it >= 0 }
 
-            val mediaItemExtras = currentMediaItem?.mediaMetadata?.extras
             val sourceCfi = mediaItemExtras?.getString("sourceCfi")
             val startOffset = mediaItemExtras?.getInt("startOffset", -1) ?: -1
             val currentWordSourceCfi = customState.getString("currentWordSourceCfi")
@@ -279,11 +315,24 @@ class TtsController(context: Context) : Player.Listener {
                 } else {
                     if (isLoading) currentState.bookTitle else serviceBookTitle
                 },
+                chapterTitle = if (isPlaybackActive || isLoading) {
+                    serviceChapterTitle ?: currentState.chapterTitle
+                } else {
+                    serviceChapterTitle
+                },
                 chapterIndex = if (isPlaybackActive || isLoading) {
                     serviceChapterIndex ?: currentState.chapterIndex
                 } else {
                     serviceChapterIndex
                 },
+                totalChapters = if (isPlaybackActive || isLoading) {
+                    serviceTotalChapters ?: currentState.totalChapters
+                } else {
+                    serviceTotalChapters
+                },
+                currentChunkIndex = serviceCurrentChunkIndex,
+                totalChunks = serviceTotalChunks,
+                bookProgressPercent = serviceBookProgressPercent,
                 speakerId = serviceSpeaker,
                 sourceCfi = if (isPlaybackActive) {
                     sourceCfi

app/src/main/java/com/aryan/reader/tts/TtsPlaybackManager.kt

@@ -48,6 +48,7 @@ import androidx.core.net.toUri
 import com.aryan.reader.paginatedreader.TimedWord
 import com.aryan.reader.paginatedreader.TtsChunk
 import kotlinx.coroutines.delay
+import kotlin.math.roundToInt
 
 val START_TTS_COMMAND = SessionCommand("com.aryan.reader.tts.START", Bundle.EMPTY)
 val STOP_TTS_COMMAND = SessionCommand("com.aryan.reader.tts.STOP", Bundle.EMPTY)
@@ -57,6 +58,7 @@ private val STATE_UPDATE_COMMAND = SessionCommand("com.aryan.reader.tts.STATE_UP
 val CHANGE_TTS_MODE_COMMAND = SessionCommand("com.aryan.reader.tts.CHANGE_MODE", Bundle.EMPTY)
 val SLICE_CURRENT_AND_RELOAD_COMMAND = SessionCommand("com.aryan.reader.tts.SLICE_AND_RELOAD", Bundle.EMPTY)
 val SET_PLAYBACK_PARAMS_COMMAND = SessionCommand("com.aryan.reader.tts.SET_PLAYBACK_PARAMS", Bundle.EMPTY)
+const val TTS_NOTIFICATION_DIAG_TAG = "TTS_NOTIFICATION_DIAG"
 
 const val KEY_TEXT_CHUNKS = "KEY_TEXT_CHUNKS"
 const val KEY_SOURCE_CFIS = "KEY_SOURCE_CFIS"
@@ -71,6 +73,8 @@ const val KEY_WORD_OFFSETS = "KEY_WORD_OFFSETS"
 const val KEY_PLAYBACK_SOURCE = "KEY_PLAYBACK_SOURCE"
 const val KEY_AUTH_TOKEN = "KEY_AUTH_TOKEN"
 const val KEY_CHAPTER_INDEX = "KEY_CHAPTER_INDEX"
+const val KEY_TOTAL_CHAPTERS = "KEY_TOTAL_CHAPTERS"
+const val KEY_CONTINUE_SESSION = "KEY_CONTINUE_SESSION"
 
 private const val PREFETCH_LOOKAHEAD = 3
 
@@ -102,7 +106,12 @@ class TtsPlaybackManager(
         val currentText: String? = null,
         val errorMessage: String? = null,
         val bookTitle: String? = null,
+        val chapterTitle: String? = null,
         val chapterIndex: Int? = null,
+        val totalChapters: Int? = null,
+        val currentChunkIndex: Int = -1,
+        val totalChunks: Int = 0,
+        val bookProgressPercent: Int? = null,
         val speakerId: String = DEFAULT_SPEAKER_ID,
         val sourceCfi: String? = null,
         val startOffsetInSource: Int = -1,
@@ -124,6 +133,8 @@ class TtsPlaybackManager(
     private var chapterTitle: String? = null
     private var coverImageUri: String? = null
     private var currentTtsMode = TtsMode.CLOUD
+    private var chapterIndex: Int? = null
+    private var totalChapters: Int? = null
 
     init {
         player.addListener(this)
@@ -146,6 +157,9 @@ class TtsPlaybackManager(
         session: MediaSession,
         controller: MediaSession.ControllerInfo
     ): MediaSession.ConnectionResult {
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+            "MediaSession onConnect. package=${controller.packageName}, uid=${controller.uid}"
+        )
         val availableSessionCommands = MediaSession.ConnectionResult.DEFAULT_SESSION_COMMANDS.buildUpon()
             .add(START_TTS_COMMAND)
             .add(STOP_TTS_COMMAND)
@@ -186,6 +200,9 @@ class TtsPlaybackManager(
             START_TTS_COMMAND -> {
                 val chunks = args.getStringArrayList(KEY_TEXT_CHUNKS) ?: emptyList()
                 Timber.d("TtsService: START command received. Size: ${chunks.size}")
+                Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+                    "START command received. chunks=${chunks.size}, continueSession=${args.getBoolean(KEY_CONTINUE_SESSION, false)}, source=${args.getString(KEY_PLAYBACK_SOURCE)}, mode=${args.getString(KEY_TTS_MODE)}, chapterIndex=${args.getInt(KEY_CHAPTER_INDEX, -1)}, totalChapters=${args.getInt(KEY_TOTAL_CHAPTERS, -1)}"
+                )
                 val cfis = args.getStringArrayList(KEY_SOURCE_CFIS)
                 val offsets = args.getIntegerArrayList(KEY_START_OFFSETS)
                 val speakerId = args.getString(KEY_SPEAKER_ID, DEFAULT_SPEAKER_ID)
@@ -193,6 +210,7 @@ class TtsPlaybackManager(
                 val chapterTitle = args.getString(KEY_CHAPTER_TITLE)
                 val coverImageUri = args.getString(KEY_COVER_IMAGE_URI)
                 val chapterIndex = args.getInt(KEY_CHAPTER_INDEX, -1).takeIf { it >= 0 }
+                val totalChapters = args.getInt(KEY_TOTAL_CHAPTERS, -1).takeIf { it > 0 }
                 val ttsModeName = args.getString(KEY_TTS_MODE, TtsMode.CLOUD.name)
                 val playbackSource = args.getString(KEY_PLAYBACK_SOURCE)
                 val ttsMode = try { TtsMode.valueOf(ttsModeName ?: TtsMode.CLOUD.name) } catch (_: Exception) { TtsMode.CLOUD }
@@ -208,10 +226,11 @@ class TtsPlaybackManager(
 
                 val authToken = args.getString(KEY_AUTH_TOKEN)
                 Timber.tag("TTS_CLOUD_DIAG").d("TtsPlaybackManager received START. Token present: ${!authToken.isNullOrBlank()}")
-                handleStartTts(richChunks, speakerId, bookTitle, chapterTitle, coverImageUri, chapterIndex, ttsMode, playbackSource, args)
+                handleStartTts(richChunks, speakerId, bookTitle, chapterTitle, coverImageUri, chapterIndex, totalChapters, ttsMode, playbackSource, args)
             }
             STOP_TTS_COMMAND -> {
                 Timber.d("Received STOP command.")
+                Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i("STOP command received.")
                 handleStopTts(userInitiated = true)
             }
             CHANGE_SPEAKER_COMMAND -> {
@@ -342,17 +361,20 @@ class TtsPlaybackManager(
         chapterTitle: String?,
         coverImageUri: String?,
         chapterIndex: Int?,
+        totalChapters: Int?,
         ttsMode: TtsMode,
         playbackSource: String?,
         args: Bundle // Added this parameter
     ) {
         if (chunks.isEmpty()) {
             _ttsState.value = _ttsState.value.copy(errorMessage = "No text to read.")
+            Timber.tag(TTS_NOTIFICATION_DIAG_TAG).w("handleStartTts aborted because chunks is empty.")
             return
         }
 
         // --- YOUR SNIPPET START ---
         val authToken = args.getString(KEY_AUTH_TOKEN)
+        val continueSession = args.getBoolean(KEY_CONTINUE_SESSION, false)
         val speed = args.getFloat("playback_speed", 1f)
         val pitch = args.getFloat("playback_pitch", 1f)
 
@@ -365,27 +387,54 @@ class TtsPlaybackManager(
         }
 
         Timber.tag("TTS_CLOUD_DIAG").d("TtsPlaybackManager received START. Token present: ${!authToken.isNullOrBlank()}")
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+            "handleStartTts. continueSession=$continueSession, chunks=${chunks.size}, book='${bookTitle.orEmpty().take(60)}', chapter='${chapterTitle.orEmpty().take(60)}', chapterIndex=$chapterIndex, totalChapters=$totalChapters, mode=$ttsMode, playbackSource=$playbackSource"
+        )
+
+        if (!continueSession) {
+            Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i("New TTS session. Calling handleStopTts(clearState=false) before start.")
+            handleStopTts(clearState = false)
+        }
 
-        handleStopTts(clearState = false)
         textChunks = chunks
         currentSpeakerId = speakerId
         currentTtsMode = ttsMode
         this.bookTitle = bookTitle
         this.chapterTitle = chapterTitle
         this.coverImageUri = coverImageUri
+        this.chapterIndex = chapterIndex
+        this.totalChapters = totalChapters
 
-        onResetContext()
         loadedChunks.clear()
         lastPrefetchIndex = -1
 
         _ttsState.value = TtsState(
             isLoading = true,
             bookTitle = bookTitle,
+            chapterTitle = chapterTitle,
             chapterIndex = chapterIndex,
+            totalChapters = totalChapters,
+            currentChunkIndex = -1,
+            totalChunks = chunks.size,
+            bookProgressPercent = calculateBookProgressPercent(-1),
             speakerId = speakerId,
             playbackSource = playbackSource,
-            ttsMode = ttsMode.name
+            ttsMode = ttsMode.name,
+            currentText = if (continueSession) _ttsState.value.currentText else null
         )
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+            "TTS state set to loading. bookProgress=${_ttsState.value.bookProgressPercent}, currentTextRetained=${_ttsState.value.currentText != null}"
+        )
+
+        if (continueSession) {
+            Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i("Continuation start. Cancelling prefetch/tracking but keeping player session alive until replacement media is ready.")
+            preparationJob?.cancel()
+            wordTrackingJob?.cancel()
+            prefetchLoopJob?.cancel()
+            prefetchingJobs.values.forEach { it.cancel() }
+            prefetchingJobs.clear()
+            clearPlaylistForContinuation()
+        }
 
         currentAuthToken = authToken
         preparationJob = scope.launch {
@@ -411,6 +460,73 @@ class TtsPlaybackManager(
         Timber.d("Speaker changed to $newSpeakerId (pending next start)")
     }
 
+    private fun currentChunkIndexFromPlayer(): Int {
+        return player.currentMediaItem?.mediaId?.toIntOrNull()
+            ?: player.currentMediaItemIndex
+    }
+
+    private fun calculateBookProgressPercent(chunkIndex: Int): Int? {
+        val chapter = chapterIndex ?: return null
+        val chapterCount = totalChapters?.takeIf { it > 0 } ?: return null
+        val safeChunkProgress = if (textChunks.isNotEmpty() && chunkIndex >= 0) {
+            ((chunkIndex + 1).toDouble() / textChunks.size.toDouble()).coerceIn(0.0, 1.0)
+        } else {
+            0.0
+        }
+        return (((chapter.toDouble() + safeChunkProgress) / chapterCount.toDouble()) * 100.0)
+            .roundToInt()
+            .coerceIn(0, 100)
+    }
+
+    private fun markSessionFinishedNaturally(chunkIndex: Int) {
+        val currentState = _ttsState.value
+        if (currentState.isLoading && currentState.currentChunkIndex == -1) {
+            Timber.tag("TTS_CHAPTER_CHANGE_DIAG").d(
+                "Ignoring stale streamed completion while a continuation session is loading."
+            )
+            return
+        }
+
+        val safeChunkIndex = if (textChunks.isNotEmpty()) {
+            chunkIndex.coerceIn(0, textChunks.lastIndex)
+        } else {
+            -1
+        }
+
+        Timber.tag("TTS_CHAPTER_CHANGE_DIAG").i(
+            "Setting sessionFinished = true for naturally completed streamed TTS. chunk=$safeChunkIndex, totalChunks=${textChunks.size}"
+        )
+
+        _ttsState.value = _ttsState.value.copy(
+            isPlaying = false,
+            isLoading = false,
+            currentChunkIndex = safeChunkIndex,
+            totalChunks = textChunks.size,
+            bookProgressPercent = calculateBookProgressPercent(safeChunkIndex),
+            currentWordSourceCfi = null,
+            currentWordStartOffset = -1,
+            sessionFinished = true
+        )
+    }
+
+    private fun clearPlaylistForContinuation() {
+        val filesToDelete = audioFiles.values.toList()
+        val streamsToRemove = chunkStreamIds.values.toList()
+        audioFiles.clear()
+        chunkStreamIds.clear()
+        loadedChunks.clear()
+
+        lastPrefetchIndex = -1
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+            "Cleared continuation temp resources. oldFiles=${filesToDelete.size}, oldStreams=${streamsToRemove.size}"
+        )
+
+        scope.launch(Dispatchers.IO) {
+            filesToDelete.forEach { deleteTempFile(it) }
+            streamsToRemove.forEach { StreamRegistry.remove(it) }
+        }
+    }
+
     private suspend fun prepareAndPlayFirstChunk(startAtIndex: Int = 0, playWhenReady: Boolean = true, startAtPosition: Long = 0L) {
         val firstChunk = textChunks.getOrNull(startAtIndex)
         if (firstChunk == null) {
@@ -420,6 +536,9 @@ class TtsPlaybackManager(
 
         val chunkStartTime = System.currentTimeMillis()
         Timber.tag("TTS_CLOUD_DIAG").i("Starting audio generation for first chunk (index=$startAtIndex).")
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+            "Preparing first chunk. startAtIndex=$startAtIndex, playWhenReady=$playWhenReady"
+        )
 
         val ttsAudioData = generateAudioChunk(bookTitle ?: "Unknown Book", chapterTitle, startAtIndex, textChunks.size, firstChunk.text, currentSpeakerId, currentTtsMode, currentAuthToken)
         Timber.tag("TTS_CLOUD_DIAG").i("generateAudioChunk returned in ${System.currentTimeMillis() - chunkStartTime}ms")
@@ -464,17 +583,30 @@ class TtsPlaybackManager(
                 }
                 player.playWhenReady = playWhenReady
                 Timber.tag("TTS_CLOUD_DIAG").i("ExoPlayer setMediaItem & prepare called in ${System.currentTimeMillis() - prepStartTime}ms")
+                Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+                    "Player prepared for TTS. mediaId=${mediaItem.mediaId}, title='${mediaItem.mediaMetadata.title}', playWhenReady=${player.playWhenReady}, playbackState=${player.playbackState}, mediaItems=${player.mediaItemCount}"
+                )
                 _ttsState.value = _ttsState.value.copy(
                     isLoading = false,
                     isPlaying = playWhenReady,
                     currentText = serverText,
+                    chapterTitle = chapterTitle,
+                    chapterIndex = chapterIndex,
+                    totalChapters = totalChapters,
+                    currentChunkIndex = startAtIndex,
+                    totalChunks = textChunks.size,
+                    bookProgressPercent = calculateBookProgressPercent(startAtIndex),
+                    sessionFinished = false,
                     sourceCfi = updatedChunk.sourceCfi,
                     startOffsetInSource = updatedChunk.startOffsetInSource
                 )
             }
             prefetchNextChunkAudio(startAtIndex)
         } else {
-            _ttsState.value = _ttsState.value.copy(isLoading = false, errorMessage = "Failed to load audio.")
+            _ttsState.value = _ttsState.value.copy(
+                isLoading = false,
+                errorMessage = ttsAudioData.error ?: "Failed to load audio."
+            )
         }
     }
 
@@ -509,6 +641,9 @@ class TtsPlaybackManager(
 
     private fun handleStopTts(clearState: Boolean = true, userInitiated: Boolean = false) {
         Timber.tag("TTS_CLOUD_DIAG").d("handleStopTts called. clearState=$clearState, userInitiated=$userInitiated")
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+            "handleStopTts. clearState=$clearState, userInitiated=$userInitiated"
+        )
         onResetContext()
         preparationJob?.cancel()
         wordTrackingJob?.cancel()
@@ -527,6 +662,11 @@ class TtsPlaybackManager(
         player.stop()
         player.clearMediaItems()
         textChunks = emptyList()
+        bookTitle = null
+        chapterTitle = null
+        coverImageUri = null
+        chapterIndex = null
+        totalChapters = null
         lastPrefetchIndex = -1
         prefetchLoopJob?.cancel()
         prefetchingJobs.values.forEach { it.cancel() }
@@ -541,17 +681,27 @@ class TtsPlaybackManager(
     override fun onMediaItemTransition(mediaItem: MediaItem?, reason: Int) {
         val newPlaylistIndex = player.currentMediaItemIndex
         Timber.tag("TTS_CLOUD_DIAG").d("onMediaItemTransition to playlistIndex: $newPlaylistIndex, mediaId: ${mediaItem?.mediaId}, reason: $reason")
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+            "onMediaItemTransition. playlistIndex=$newPlaylistIndex, mediaId=${mediaItem?.mediaId}, reason=$reason, title='${mediaItem?.mediaMetadata?.title}', playbackState=${player.playbackState}, isPlaying=${player.isPlaying}"
+        )
         if (newPlaylistIndex == C.INDEX_UNSET) return
 
         val currentChunkIndex = mediaItem?.mediaId?.toIntOrNull() ?: return
 
-        val newText = mediaItem.mediaMetadata.subtitle?.toString()
         val extras = mediaItem.mediaMetadata.extras
+        val newText = extras?.getString("ttsText") ?: mediaItem.mediaMetadata.subtitle?.toString()
         val sourceCfi = extras?.getString("sourceCfi")
         val startOffset = extras?.getInt("startOffset", -1) ?: -1
 
         _ttsState.value = _ttsState.value.copy(
             currentText = newText,
+            chapterTitle = chapterTitle,
+            chapterIndex = chapterIndex,
+            totalChapters = totalChapters,
+            currentChunkIndex = currentChunkIndex,
+            totalChunks = textChunks.size,
+            bookProgressPercent = calculateBookProgressPercent(currentChunkIndex),
+            sessionFinished = false,
             sourceCfi = sourceCfi,
             startOffsetInSource = startOffset
         )
@@ -582,6 +732,9 @@ class TtsPlaybackManager(
     }
 
     override fun onIsPlayingChanged(isPlaying: Boolean) {
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+            "onIsPlayingChanged. isPlaying=$isPlaying, playbackState=${player.playbackState}, playWhenReady=${player.playWhenReady}, mediaItems=${player.mediaItemCount}, currentIndex=${player.currentMediaItemIndex}"
+        )
         var nextState = _ttsState.value.copy(isPlaying = isPlaying)
 
         if (isPlaying) {
@@ -599,14 +752,22 @@ class TtsPlaybackManager(
                 currentWordStartOffset = -1
             )
 
-            val currentChunkIndex = player.currentMediaItemIndex
+            val currentChunkIndex = currentChunkIndexFromPlayer()
             val isLastChunkInSession = textChunks.isNotEmpty() && currentChunkIndex == textChunks.size - 1
 
             if (player.playbackState == Player.STATE_ENDED) {
                 Timber.tag("TTS_CHAPTER_CHANGE_DIAG").d("ExoPlayer STATE_ENDED. currentChunkIndex: $currentChunkIndex, isLastChunk: $isLastChunkInSession, totalChunks: ${textChunks.size}")
+                Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+                    "Player reached ENDED. currentChunkIndex=$currentChunkIndex, isLastChunk=$isLastChunkInSession, totalChunks=${textChunks.size}, sessionFinishedWillBeSet=${isLastChunkInSession || textChunks.isEmpty()}"
+                )
                 if (isLastChunkInSession || textChunks.isEmpty()) {
                     Timber.tag("TTS_CHAPTER_CHANGE_DIAG").i("Setting sessionFinished = true")
-                    nextState = nextState.copy(sessionFinished = true)
+                    nextState = nextState.copy(
+                        currentChunkIndex = currentChunkIndex,
+                        totalChunks = textChunks.size,
+                        bookProgressPercent = calculateBookProgressPercent(currentChunkIndex),
+                        sessionFinished = true
+                    )
                 } else {
                     val nextIdx = currentChunkIndex + 1
                     val isPrefetching = prefetchingJobs.containsKey(nextIdx)
@@ -625,6 +786,7 @@ class TtsPlaybackManager(
         if (!isPlaying && player.playbackState == Player.STATE_IDLE) {
             if (!nextState.sessionEndedByStop && !nextState.isLoading && preparationJob?.isActive != true) {
                 Timber.tag("TTS_CLOUD_DIAG").d("Auto-stopping TTS from onIsPlayingChanged (IDLE and not loading)")
+                Timber.tag(TTS_NOTIFICATION_DIAG_TAG).w("Auto-stopping from IDLE/not-loading path.")
                 handleStopTts(userInitiated = true)
             } else {
                 Timber.tag("TTS_CLOUD_DIAG").d("Ignoring STATE_IDLE in onIsPlayingChanged because isLoading=${nextState.isLoading}, preparationJob.isActive=${preparationJob?.isActive}")
@@ -634,6 +796,7 @@ class TtsPlaybackManager(
 
     override fun onPlayerError(error: androidx.media3.common.PlaybackException) {
         Timber.tag("TTS_CLOUD_DIAG").e(error, "Player error: [${error.errorCodeName}] ${error.message}")
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).e(error, "Player error. code=${error.errorCodeName}, message=${error.message}")
         _ttsState.value = _ttsState.value.copy(errorMessage = "Playback error: ${error.message}")
         handleStopTts(userInitiated = true)
     }
@@ -719,10 +882,13 @@ class TtsPlaybackManager(
                                     player.addMediaItem(insertPosition, nextMediaItem)
                                 }
 
-                                if (player.playbackState == Player.STATE_ENDED && player.playWhenReady && targetIndex == player.currentMediaItemIndex + 1) {
+                                val currentChunkIndex = currentChunkIndexFromPlayer()
+                                val isImmediateNextChunk = targetIndex == currentChunkIndex + 1
+
+                                if (player.playbackState == Player.STATE_ENDED && player.playWhenReady && isImmediateNextChunk) {
                                     player.seekToNextMediaItem()
                                     player.play()
-                                } else if (wasLoading && targetIndex == player.currentMediaItemIndex + 1) {
+                                } else if (wasLoading && isImmediateNextChunk) {
                                     _ttsState.value = _ttsState.value.copy(isLoading = false)
                                 }
                             }
@@ -768,7 +934,10 @@ class TtsPlaybackManager(
                                     if (player.hasNextMediaItem()) {
                                         player.seekToNextMediaItem()
                                     } else {
-                                        player.stop()
+                                        val finishedChunkIndex = currentMediaItem.mediaId.toIntOrNull()
+                                            ?: currentChunkIndexFromPlayer()
+                                        markSessionFinishedNaturally(finishedChunkIndex)
+                                        player.pause()
                                     }
                                 }
                             }
@@ -811,7 +980,37 @@ class TtsPlaybackManager(
     }
 
     private fun createMediaItem(text: String, path: String, index: Int, chunk: TtsChunk): MediaItem {
+        val progress = calculateBookProgressPercent(index)
+        val chunkLabel = if (textChunks.isNotEmpty()) {
+            "Chunk ${index + 1}/${textChunks.size}"
+        } else {
+            null
+        }
+        val chapterLabel = buildString {
+            val chapter = chapterIndex
+            val chapterCount = totalChapters
+            if (chapter != null && chapterCount != null) {
+                append("Chapter ${chapter + 1} of $chapterCount")
+                if (!chapterTitle.isNullOrBlank()) append(": $chapterTitle")
+            } else if (!chapterTitle.isNullOrBlank()) {
+                append(chapterTitle)
+            }
+            if (progress != null) {
+                if (isNotEmpty()) append(" - ")
+                append("$progress%")
+            }
+            if (chunkLabel != null) {
+                if (isNotEmpty()) append(" - ")
+                append(chunkLabel)
+            }
+        }.ifBlank { chapterTitle ?: chunkLabel ?: "TTS" }
+        val chunkPreview = text
+            .replace(Regex("\\s+"), " ")
+            .trim()
+            .take(180)
+
         val extras = Bundle().apply {
+            putString("ttsText", text)
             putString("sourceCfi", chunk.sourceCfi)
             putInt("startOffset", chunk.startOffsetInSource)
             if (chunk.timedWords.isNotEmpty()) {
@@ -823,9 +1022,11 @@ class TtsPlaybackManager(
         }
 
         val metadata = MediaMetadata.Builder()
-            .setArtist(bookTitle)
-            .setTitle(chapterTitle)
-            .setSubtitle(text)
+            .setTitle(bookTitle ?: chapterLabel)
+            .setDisplayTitle(bookTitle ?: chapterLabel)
+            .setArtist(chapterLabel)
+            .setSubtitle(chunkPreview)
+            .setDescription(chunkPreview)
             .setArtworkUri(coverImageUri?.toUri())
             .setTrackNumber(index + 1)
             .setTotalTrackCount(textChunks.size)
@@ -865,7 +1066,12 @@ class TtsPlaybackManager(
             putBoolean("isLoading", state.isLoading)
             putString("errorMessage", state.errorMessage)
             putString("bookTitle", state.bookTitle)
+            putString("chapterTitle", state.chapterTitle)
             putInt("chapterIndex", state.chapterIndex ?: -1)
+            putInt("totalChapters", state.totalChapters ?: -1)
+            putInt("currentChunkIndex", state.currentChunkIndex)
+            putInt("totalChunks", state.totalChunks)
+            putInt("bookProgressPercent", state.bookProgressPercent ?: -1)
             putString("speakerId", state.speakerId)
             putBoolean("sessionEndedByStop", state.sessionEndedByStop)
             putString("currentWordSourceCfi", state.currentWordSourceCfi)
@@ -905,5 +1111,8 @@ class TtsPlaybackManager(
             else -> "UNKNOWN"
         }
         Timber.tag("TTS_CLOUD_DIAG").d("ExoPlayer playback state changed: $stateName")
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+            "onPlaybackStateChanged. state=$stateName, isPlaying=${player.isPlaying}, playWhenReady=${player.playWhenReady}, mediaItems=${player.mediaItemCount}, currentIndex=${player.currentMediaItemIndex}"
+        )
     }
 }

app/src/main/java/com/aryan/reader/tts/TtsService.kt

@@ -30,6 +30,9 @@ import androidx.media3.common.util.UnstableApi
 import androidx.media3.exoplayer.ExoPlayer
 import androidx.media3.session.MediaSession
 import androidx.media3.session.MediaSessionService
+import com.aryan.reader.GEMINI_CLOUD_TTS_MODEL
+import com.aryan.reader.isByokCloudTtsAvailable
+import com.aryan.reader.loadAiByokSettings
 import com.aryan.reader.tts.TtsPlaybackManager.TtsMode
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
@@ -236,16 +239,31 @@ class TtsService : MediaSessionService() {
     private lateinit var cacheManager: TtsCacheManager
 
     override fun onUpdateNotification(session: MediaSession, startInForegroundRequired: Boolean) {
+        val hasNotificationPermission = Build.VERSION.SDK_INT < Build.VERSION_CODES.TIRAMISU ||
+            ContextCompat.checkSelfPermission(this, Manifest.permission.POST_NOTIFICATIONS) == PackageManager.PERMISSION_GRANTED
+        val playerState = if (::player.isInitialized) {
+            "playbackState=${player.playbackState}, isPlaying=${player.isPlaying}, playWhenReady=${player.playWhenReady}, mediaItems=${player.mediaItemCount}, currentIndex=${player.currentMediaItemIndex}"
+        } else {
+            "player=uninitialized"
+        }
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+            "onUpdateNotification called. startInForegroundRequired=$startInForegroundRequired, hasPostNotifications=$hasNotificationPermission, $playerState"
+        )
+
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU &&
             ContextCompat.checkSelfPermission(this, Manifest.permission.POST_NOTIFICATIONS) != PackageManager.PERMISSION_GRANTED) {
 
             if (startInForegroundRequired) {
+                Timber.tag(TTS_NOTIFICATION_DIAG_TAG).w("Notification permission missing while foreground is required. Calling stopSelf().")
                 stopSelf()
+            } else {
+                Timber.tag(TTS_NOTIFICATION_DIAG_TAG).w("Notification permission missing. Skipping notification update.")
             }
 
             return
         }
 
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i("Delegating notification update to MediaSessionService.")
         super.onUpdateNotification(session, startInForegroundRequired)
     }
 
@@ -279,7 +297,12 @@ class TtsService : MediaSessionService() {
             data class Error(val message: String) : GeminiWsEvent()
         }
 
-        suspend fun ensureConnected(serverUrl: String, speaker: String, authToken: String?) = connectionMutex.withLock {
+        suspend fun ensureConnected(
+            serverUrl: String,
+            speaker: String,
+            authToken: String?,
+            directGeminiApiKey: String? = null
+        ) = connectionMutex.withLock {
             if (webSocket != null) {
                 if (connectedSpeaker == speaker) {
                     val isSetup = try { setupDeferred.await() } catch(_: Exception) { false }
@@ -290,11 +313,15 @@ class TtsService : MediaSessionService() {
                 webSocket = null
             }
 
-            val sanitizedUrl = serverUrl.removeSuffix("/")
-            val wsUrlStr = sanitizedUrl.replace("https://", "wss://").replace("http://", "ws://")
-            val url = "$wsUrlStr/live?speaker=$speaker&token=${authToken ?: ""}"
+            val url = if (!directGeminiApiKey.isNullOrBlank()) {
+                "wss://generativelanguage.googleapis.com/ws/google.ai.generativelanguage.v1beta.GenerativeService.BidiGenerateContent?key=$directGeminiApiKey"
+            } else {
+                val sanitizedUrl = serverUrl.removeSuffix("/")
+                val wsUrlStr = sanitizedUrl.replace("https://", "wss://").replace("http://", "ws://")
+                "$wsUrlStr/live?speaker=$speaker&token=${authToken ?: ""}"
+            }
 
-            Timber.tag("TTS_CLOUD_DIAG").d("Connecting to WS: $url")
+            Timber.tag("TTS_CLOUD_DIAG").d("Connecting to WS: ${if (!directGeminiApiKey.isNullOrBlank()) "Gemini BYOK" else url}")
             val request = Request.Builder().url(url).build()
             val connectedDeferred = CompletableDeferred<Boolean>()
 
@@ -316,7 +343,7 @@ class TtsService : MediaSessionService() {
 
                     val setupMsg = JSONObject().apply {
                         put("setup", JSONObject().apply {
-                            put("model", "models/gemini-3.1-flash-live-preview")
+                            put("model", "models/$GEMINI_CLOUD_TTS_MODEL")
                             put("systemInstruction", JSONObject().apply {
                                 put("parts", org.json.JSONArray().apply {
                                     put(JSONObject().apply {
@@ -552,8 +579,17 @@ class TtsService : MediaSessionService() {
                         TtsAudioData(audioFile = cachedFile, serverText = text, wordTimings = emptyList(), error = null, streamUri = null)
                     } else {
                         try {
-                            liveClient.ensureConnected(googleCloudWorkerTtsUrl, speaker, authToken)
-                            liveClient.generateChunk(text, cachedFile)
+                            val directGeminiApiKey = if (isByokCloudTtsAvailable(this@TtsService)) {
+                                loadAiByokSettings(this@TtsService).geminiKey
+                            } else {
+                                null
+                            }
+                            if (directGeminiApiKey.isNullOrBlank() && googleCloudWorkerTtsUrl.isBlank()) {
+                                TtsAudioData(audioFile = null, serverText = null, wordTimings = null, error = "Cloud TTS is not configured.")
+                            } else {
+                                liveClient.ensureConnected(googleCloudWorkerTtsUrl, speaker, authToken, directGeminiApiKey)
+                                liveClient.generateChunk(text, cachedFile)
+                            }
                         } catch (e: Exception) {
                             Timber.tag("TTS_CLOUD_DIAG").e(e, "Cloud TTS generation failed")
                             TtsAudioData(audioFile = null, serverText = null, wordTimings = null, error = e.message ?: "Failed to connect to TTS service")
@@ -567,6 +603,11 @@ class TtsService : MediaSessionService() {
     override fun onCreate() {
         super.onCreate()
         Timber.d("TtsService created.")
+        val hasNotificationPermission = Build.VERSION.SDK_INT < Build.VERSION_CODES.TIRAMISU ||
+            ContextCompat.checkSelfPermission(this, Manifest.permission.POST_NOTIFICATIONS) == PackageManager.PERMISSION_GRANTED
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+            "TtsService onCreate. sdk=${Build.VERSION.SDK_INT}, hasPostNotifications=$hasNotificationPermission"
+        )
 
         cacheManager = TtsCacheManager(this)
 
@@ -622,6 +663,7 @@ class TtsService : MediaSessionService() {
             .setHandleAudioBecomingNoisy(true)
             .setMediaSourceFactory(androidx.media3.exoplayer.source.DefaultMediaSourceFactory(this).setDataSourceFactory(dataSourceFactory))
             .build()
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i("ExoPlayer created for TTS service.")
 
         playbackManager = TtsPlaybackManager(
             player = player,
@@ -634,21 +676,30 @@ class TtsService : MediaSessionService() {
             .build()
 
         mediaSession?.let { playbackManager.setMediaSession(it) }
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i("MediaSession created and attached to playback manager. sessionAvailable=${mediaSession != null}")
     }
 
     override fun onTaskRemoved(rootIntent: Intent?) {
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+            "onTaskRemoved. playWhenReady=${if (::player.isInitialized) player.playWhenReady else null}, isPlaying=${if (::player.isInitialized) player.isPlaying else null}"
+        )
         if (!player.playWhenReady) {
+            Timber.tag(TTS_NOTIFICATION_DIAG_TAG).w("Task removed while player is not playWhenReady. Calling stopSelf().")
             stopSelf()
         }
         Timber.d("onTaskRemoved called, stopping service.")
     }
 
     override fun onGetSession(controllerInfo: MediaSession.ControllerInfo): MediaSession? {
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).i(
+            "onGetSession. package=${controllerInfo.packageName}, sessionAvailable=${mediaSession != null}"
+        )
         return mediaSession
     }
 
     override fun onDestroy() {
         Timber.d("TtsService is being destroyed.")
+        Timber.tag(TTS_NOTIFICATION_DIAG_TAG).w("TtsService onDestroy.")
         baseTtsSynthesizer.shutdown()
         playbackManager.release()
         mediaSession?.run {

app/src/main/res/values/strings.xml

@@ -102,6 +102,7 @@
     <!-- "Google Drive" is a brand name — do not translate. -->
     <string name="drawer_backup_desc">Upload books from your synced folders to Google Drive.</string>
     <string name="drawer_custom_fonts">Custom Fonts</string>
+    <string name="drawer_support_project">Support the Project</string>
     <string name="drawer_help_feedback">Help &amp; Feedback</string>
     <string name="drawer_sign_out">Sign Out</string>
 
@@ -317,6 +318,15 @@
     <string name="email_support">Email Support</string>
     <string name="email_support_desc">Contact us directly via email for any other inquiries.</string>
 
+    <!-- Support Project -->
+    <string name="support_project_title">Support the Project</string>
+    <string name="support_project_heading">Help keep Episteme moving</string>
+    <string name="support_project_desc">Your support helps me keep maintaining and Improving Episteme for everyone!!!</string>
+    <string name="support_github_sponsor">Sponsor on GitHub</string>
+    <string name="support_github_sponsor_desc">Support development directly through GitHub Sponsors. As a thank you, you get a README shoutout in the project repo.</string>
+    <string name="support_patreon">Join on Patreon</string>
+    <string name="support_patreon_desc">As a thank you for backing the app, Patreon supporters get extra content and benefits: sneak peeks at what I am working on, early screenshots and updates, votes that help shape how new features should look and work, and a README shoutout in the project repo.</string>
+
     <!-- Dialogs -->
     <!-- "Episteme Pro" is the product tier name — do not translate "Episteme". -->
     <string name="dialog_unlock_pro">Unlock Episteme Pro</string>
@@ -573,10 +583,14 @@
     <!-- Common.kt: ReaderThemePanel & ThemeBuilderView -->
     <string name="reading_themes">Reading Themes</string>
     <string name="theme_presets">Presets</string>
+    <string name="theme_textured_presets">Textured Presets</string>
     <string name="theme_my_themes">My Themes</string>
+    <string name="theme_my_textured_themes">My Textured Themes</string>
     <!-- "+" is a literal plus icon reference in the description. -->
     <string name="theme_no_custom">No custom themes yet. Tap \'+\' to create one.</string>
+    <string name="theme_no_textured_custom">No custom textured themes yet.</string>
     <string name="theme_new">New Theme</string>
+    <string name="theme_new_textured">New Textured Theme</string>
     <string name="theme_edit">Edit Theme</string>
     <string name="theme_name">Theme Name</string>
     <!-- Short motivational quote used as preview text in the theme builder. -->
@@ -587,6 +601,10 @@
     <string name="theme_low_contrast_warning">⚠️ Low contrast! This might cause eye strain.</string>
     <string name="theme_page_color">Page Color</string>
     <string name="theme_text_color">Text Color</string>
+    <string name="theme_texture">Texture</string>
+    <string name="theme_texture_none">None</string>
+    <string name="theme_texture_upload">Upload</string>
+    <string name="theme_texture_transparency">Texture Transparency</string>
     <string name="theme_color_live_preview">Live Preview</string>
     <!-- Short phrase shown in the live color preview area of the theme builder. -->
     <string name="theme_color_preview_text">Reading is dreaming.</string>
@@ -808,7 +826,8 @@
     <string name="visual_options_system_ui">System UI (Status &amp; Navigation Bars)</string>
     <string name="visual_options_system_ui_desc">Control the visibility of the device\'s system bars.</string>
     <string name="visual_options_progress_bar">Progress Bar</string>
-    <string name="visual_options_progress_bar_desc">The reading progress and chapter indicator at the bottom of the screen.</string>
+    <string name="visual_options_progress_bar_desc">The reading progress and chapter indicator on the reading screen.</string>
+    <string name="visual_options_progress_bar_position">Position</string>
     <!-- "Seamless Chapter Transition" is a reading feature name. -->
     <string name="visual_options_seamless_chapter">Seamless Chapter Transition</string>
     <string name="visual_options_seamless_chapter_desc">Instantly load the next/previous chapter when scrolling past the end, without the pull-to-refresh animation.</string>
@@ -871,6 +890,7 @@
     <string name="label_paragraph_gap">Paragraph Gap</string>
     <string name="label_image_size">Image Size</string>
     <string name="label_horizontal_margin">Horizontal Margin</string>
+    <string name="label_vertical_margin">Vertical Margin</string>
     <string name="label_none">None</string>
     <!-- Short label for the "Original" font option in the reader settings. "Orig" is an abbreviation. -->
     <string name="label_original">Orig</string>
@@ -1214,6 +1234,7 @@
     <string name="msg_downloading_bubble_zoom_model_progress">Downloading Bubble Zoom model… %1$d%%</string>
     <string name="content_desc_exit_slider_navigation">Exit slider navigation</string>
     <string name="content_desc_jump_back">Jump Back</string>
+    <string name="content_desc_jump_forward">Jump Forward</string>
     <string name="content_desc_scroll_to_reading_page">Scroll to reading page</string>
     <string name="content_desc_annotated_page">Annotated Page</string>
     <string name="content_desc_close_image">Close Image</string>
@@ -1261,9 +1282,9 @@
     <string name="label_short">Short</string>
     <string name="label_long">Long</string>
     <!-- Compact TTS speed label. %1$s = formatted multiplier, e.g. 1.2. -->
-    <string name="tts_speed_short">Spd: %1$sx</string>
+    <string name="tts_speed_short">Speed: %1$sx</string>
     <!-- Compact TTS pitch label. %1$s = formatted multiplier, e.g. 1.0. -->
-    <string name="tts_pitch_short">Ptch: %1$sx</string>
+    <string name="tts_pitch_short">Pitch: %1$sx</string>
     <string name="content_desc_play_pause">Play/Pause</string>
     <string name="content_desc_reset_speed">Reset Speed</string>
     <string name="content_desc_reset_pitch">Reset Pitch</string>

app/src/test/java/com/aryan/reader/FileTypeResolverTest.kt

@@ -0,0 +1,28 @@
+package com.aryan.reader
+
+import org.junit.Assert.assertEquals
+import org.junit.Test
+
+class FileTypeResolverTest {
+
+    @Test
+    fun `transparent txt suffix preserves supported inner extension`() {
+        assertEquals(FileType.MD, resolveFileTypeFromName("notes.md.txt"))
+        assertEquals(FileType.HTML, resolveFileTypeFromName("chapter.html.txt"))
+        assertEquals(FileType.HTML, resolveFileTypeFromName("snippet.js.txt"))
+        assertEquals(FileType.EPUB, resolveFileTypeFromName("book.epub.txt"))
+    }
+
+    @Test
+    fun `plain txt remains txt when inner extension is unsupported`() {
+        assertEquals(FileType.TXT, resolveFileTypeFromName("notes.txt"))
+        assertEquals(FileType.TXT, resolveFileTypeFromName("archive.unknown.txt"))
+    }
+
+    @Test
+    fun `extension suffix preserves transparent txt wrapper`() {
+        assertEquals(".md.txt", resolveFileExtensionSuffixFromName("notes.md.txt"))
+        assertEquals(".html.txt", resolveFileExtensionSuffixFromName("chapter.html.txt"))
+        assertEquals(".txt", resolveFileExtensionSuffixFromName("notes.txt"))
+    }
+}

build.gradle.kts

@@ -1,6 +1,9 @@
-// Top-level build file where you can add configuration options common to all subprojects/modules.
+// Top-level build file where you can add configuration options common to all sub-projects/modules.
 plugins {
     alias(libs.plugins.android.application) apply false
+    alias(libs.plugins.android.library) apply false
     alias(libs.plugins.kotlin.android) apply false
+    alias(libs.plugins.kotlin.multiplatform) apply false
     alias(libs.plugins.kotlin.compose) apply false
+    alias(libs.plugins.compose.multiplatform) apply false
 }

desktopApp/build.gradle.kts

@@ -0,0 +1,55 @@
+import org.gradle.api.tasks.JavaExec
+import org.jetbrains.compose.desktop.application.dsl.TargetFormat
+
+plugins {
+    alias(libs.plugins.kotlin.multiplatform)
+    alias(libs.plugins.kotlin.compose)
+    alias(libs.plugins.compose.multiplatform)
+}
+
+kotlin {
+    jvm("desktop")
+    jvmToolchain(21)
+
+    sourceSets {
+        val desktopMain by getting {
+            dependencies {
+                implementation(project(":shared"))
+                implementation(compose.desktop.currentOs)
+                implementation(compose.material3)
+                implementation(compose.materialIconsExtended)
+                implementation("io.github.kevinnzou:compose-webview-multiplatform:2.0.3")
+                implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.7.3")
+                implementation("net.java.dev.jna:jna:5.17.0")
+            }
+        }
+    }
+}
+
+compose.desktop {
+    application {
+        mainClass = "com.aryan.reader.desktop.MainKt"
+
+        jvmArgs("--add-opens", "java.desktop/sun.awt=ALL-UNNAMED")
+        jvmArgs("--add-opens", "java.desktop/java.awt.peer=ALL-UNNAMED")
+
+        nativeDistributions {
+            targetFormats(TargetFormat.Exe, TargetFormat.Msi)
+            packageName = "Episteme"
+            packageVersion = "1.0.0"
+            description = "Episteme desktop shell"
+            vendor = "Aryan Reader"
+        }
+    }
+}
+
+afterEvaluate {
+    tasks.withType<JavaExec>().configureEach {
+        jvmArgs("--add-opens", "java.desktop/sun.awt=ALL-UNNAMED")
+        jvmArgs("--add-opens", "java.desktop/java.awt.peer=ALL-UNNAMED")
+        if (System.getProperty("os.name").contains("Mac")) {
+            jvmArgs("--add-opens", "java.desktop/sun.lwawt=ALL-UNNAMED")
+            jvmArgs("--add-opens", "java.desktop/sun.lwawt.macosx=ALL-UNNAMED")
+        }
+    }
+}

desktopApp/src/desktopMain/kotlin/com/aryan/reader/desktop/DesktopEpubLoader.kt

@@ -0,0 +1,282 @@
+package com.aryan.reader.desktop
+
+import androidx.compose.ui.text.TextStyle
+import androidx.compose.ui.unit.Constraints
+import androidx.compose.ui.unit.Density
+import androidx.compose.ui.unit.sp
+import com.aryan.reader.paginatedreader.CssParser
+import com.aryan.reader.paginatedreader.OptimizedCssRules
+import com.aryan.reader.paginatedreader.UserAgentStylesheet
+import com.aryan.reader.paginatedreader.htmlToSemanticBlocks
+import com.aryan.reader.shared.reader.SharedEpubBook
+import com.aryan.reader.shared.reader.SharedEpubChapter
+import java.io.File
+import java.util.Base64
+import java.util.UUID
+import java.util.zip.ZipFile
+
+object DesktopEpubLoader {
+    fun load(file: File): SharedEpubBook {
+        ZipFile(file).use { zip ->
+            val container = zip.readText("META-INF/container.xml")
+            val opfPath = container
+                .substringAfter("full-path=\"", missingDelimiterValue = "")
+                .substringBefore("\"")
+                .ifBlank { error("EPUB container does not point to an OPF package.") }
+            val opf = zip.readText(opfPath)
+            val basePath = opfPath.substringBeforeLast('/', missingDelimiterValue = "")
+                .let { if (it.isBlank()) "" else "$it/" }
+
+            val title = opf.tagText("title").ifBlank { file.nameWithoutExtension }
+            val author = opf.tagText("creator").ifBlank { null }
+            val manifest = parseManifest(opf)
+            val cssByPath = loadCss(zip, manifest, basePath)
+            val cssRules = parseCssRules(cssByPath)
+            val spine = Regex("<itemref[^>]*idref=[\"']([^\"']+)[\"'][^>]*/?>")
+                .findAll(opf)
+                .mapNotNull { match -> manifest[match.groupValues[1]] }
+                .toList()
+
+            val chapterPaths = spine.ifEmpty {
+                manifest.values.filter { it.endsWith(".xhtml", ignoreCase = true) || it.endsWith(".html", ignoreCase = true) }
+            }
+
+            val chapters = chapterPaths.mapIndexedNotNull { index, href ->
+                val path = normalizeZipPath(basePath + href)
+                val html = zip.readTextOrNull(path) ?: return@mapIndexedNotNull null
+                val resourceReadyHtml = html.sanitizeReaderHtml().withEmbeddedResources(zip, path)
+                val text = htmlToText(html)
+                val semanticBlocks = runCatching {
+                    htmlToSemanticBlocks(
+                        html = resourceReadyHtml,
+                        cssRules = cssRules,
+                        textStyle = TextStyle(fontSize = 18.sp),
+                        chapterAbsPath = path,
+                        extractionBasePath = "",
+                        density = Density(1f),
+                        fontFamilyMap = emptyMap(),
+                        constraints = Constraints(maxWidth = 980, maxHeight = 720)
+                    )
+                }.getOrElse { emptyList() }
+                if (text.isBlank()) {
+                    null
+                } else {
+                    SharedEpubChapter(
+                        id = "chapter_$index",
+                        title = html.tagText("h1")
+                            .ifBlank { html.tagText("h2") }
+                            .ifBlank { html.tagText("title") }
+                            .ifBlank { "Chapter ${index + 1}" },
+                        plainText = text,
+                        semanticBlocks = semanticBlocks,
+                        htmlContent = resourceReadyHtml.extractBodyOrSelf(),
+                        baseHref = path.substringBeforeLast('/', missingDelimiterValue = "")
+                    )
+                }
+            }
+
+            return SharedEpubBook(
+                id = file.absolutePath,
+                fileName = file.name,
+                title = title,
+                author = author,
+                css = cssByPath,
+                chapters = chapters.ifEmpty {
+                    listOf(
+                        SharedEpubChapter(
+                            id = UUID.randomUUID().toString(),
+                            title = title,
+                            plainText = "This EPUB opened, but no readable spine text was found by the lightweight desktop loader."
+                        )
+                    )
+                }
+            )
+        }
+    }
+
+    private fun parseManifest(opf: String): Map<String, String> {
+        return Regex("<item\\s+[^>]*>").findAll(opf).mapNotNull { match ->
+            val item = match.value
+            val id = item.attr("id")
+            val href = item.attr("href")
+            if (id.isBlank() || href.isBlank()) null else id to href
+        }.toMap()
+    }
+
+    private fun loadCss(zip: ZipFile, manifest: Map<String, String>, basePath: String): Map<String, String> {
+        return manifest.values
+            .filter { it.endsWith(".css", ignoreCase = true) }
+            .mapNotNull { href ->
+                val path = normalizeZipPath(basePath + href)
+                val css = zip.readTextOrNull(path)?.withEmbeddedCssResources(zip, path).orEmpty()
+                if (css.isBlank()) null else path to css
+            }
+            .toMap()
+    }
+
+    private fun parseCssRules(cssByPath: Map<String, String>): OptimizedCssRules {
+        val constraints = Constraints(maxWidth = 980, maxHeight = 720)
+        val baseRules = CssParser.parse(
+            cssContent = UserAgentStylesheet.default,
+            cssPath = null,
+            baseFontSizeSp = 18f,
+            density = 1f,
+            constraints = constraints,
+            isDarkTheme = false
+        ).rules
+
+        return cssByPath.entries
+            .fold(baseRules) { rules, (path, css) ->
+                if (css.isBlank()) {
+                    rules
+                } else {
+                    rules.merge(
+                        CssParser.parse(
+                            cssContent = css,
+                            cssPath = path,
+                            baseFontSizeSp = 18f,
+                            density = 1f,
+                            constraints = constraints,
+                            isDarkTheme = false
+                        ).rules
+                    )
+                }
+            }
+    }
+
+    private fun ZipFile.readText(path: String): String {
+        val entry = getEntry(path) ?: error("Missing EPUB entry: $path")
+        return getInputStream(entry).bufferedReader().use { it.readText() }
+    }
+
+    private fun ZipFile.readTextOrNull(path: String): String? {
+        val entry = getEntry(path) ?: return null
+        return getInputStream(entry).bufferedReader().use { it.readText() }
+    }
+
+    private fun String.attr(name: String): String {
+        return Regex("""\b$name=["']([^"']+)["']""").find(this)?.groupValues?.get(1).orEmpty()
+    }
+
+    private fun String.tagText(tag: String): String {
+        return Regex("<(?:[^:>]+:)?$tag\\b[^>]*>(.*?)</(?:[^:>]+:)?$tag>", RegexOption.IGNORE_CASE)
+            .find(this)
+            ?.groupValues
+            ?.get(1)
+            ?.let(::htmlToText)
+            .orEmpty()
+    }
+
+    private fun normalizeZipPath(path: String): String {
+        val parts = ArrayDeque<String>()
+        path.split('/').forEach { part ->
+            when (part) {
+                "", "." -> Unit
+                ".." -> if (parts.isNotEmpty()) parts.removeLast()
+                else -> parts.addLast(part)
+            }
+        }
+        return parts.joinToString("/")
+    }
+
+    private fun String.withEmbeddedResources(zip: ZipFile, chapterPath: String): String {
+        return replace(Regex("""(?i)\b(src|href)=["']([^"']+)["']""")) { match ->
+            val attr = match.groupValues[1]
+            val raw = match.groupValues[2]
+            if (attr.equals("href", ignoreCase = true) && !raw.looksLikeEmbeddableResource()) {
+                return@replace match.value
+            }
+            val dataUri = zip.toDataUri(raw, chapterPath)
+            if (dataUri != null) "$attr=\"$dataUri\"" else match.value
+        }
+    }
+
+    private fun String.looksLikeEmbeddableResource(): Boolean {
+        return substringBefore('#')
+            .substringBefore('?')
+            .substringAfterLast('.', "")
+            .lowercase() in setOf("css", "jpg", "jpeg", "png", "gif", "svg", "webp", "ttf", "otf", "woff", "woff2")
+    }
+
+    private fun String.sanitizeReaderHtml(): String {
+        return replace(Regex("(?is)<script\\b.*?</script>"), "")
+            .replace(Regex("(?is)<object\\b.*?</object>"), "")
+            .replace(Regex("(?is)<embed\\b[^>]*>"), "")
+            .replace(Regex("""(?i)\s+on[a-z]+\s*=\s*(['"]).*?\1"""), "")
+    }
+
+    private fun String.withEmbeddedCssResources(zip: ZipFile, cssPath: String): String {
+        return replace(Regex("""url\((['"]?)([^)'"]+)\1\)""", RegexOption.IGNORE_CASE)) { match ->
+            val raw = match.groupValues[2].trim()
+            val dataUri = zip.toDataUri(raw, cssPath)
+            if (dataUri != null) "url('$dataUri')" else match.value
+        }
+    }
+
+    private fun ZipFile.toDataUri(rawRef: String, ownerPath: String): String? {
+        val ref = rawRef.substringBefore('#').trim()
+        if (ref.isBlank() || ref.startsWith("data:", ignoreCase = true)) return null
+        if (ref.startsWith("http://", ignoreCase = true) || ref.startsWith("https://", ignoreCase = true)) return null
+        val base = ownerPath.substringBeforeLast('/', missingDelimiterValue = "")
+        val path = normalizeZipPath(if (base.isBlank()) ref else "$base/$ref")
+        val entry = getEntry(path) ?: return null
+        val bytes = getInputStream(entry).use { it.readBytes() }
+        return "data:${mimeType(path)};base64,${Base64.getEncoder().encodeToString(bytes)}"
+    }
+
+    private fun mimeType(path: String): String {
+        return when (path.substringAfterLast('.', "").lowercase()) {
+            "jpg", "jpeg" -> "image/jpeg"
+            "png" -> "image/png"
+            "gif" -> "image/gif"
+            "svg" -> "image/svg+xml"
+            "webp" -> "image/webp"
+            "ttf" -> "font/ttf"
+            "otf" -> "font/otf"
+            "woff" -> "font/woff"
+            "woff2" -> "font/woff2"
+            "css" -> "text/css"
+            "js" -> "text/javascript"
+            else -> "application/octet-stream"
+        }
+    }
+
+    private fun String.extractBodyOrSelf(): String {
+        return Regex("(?is)<body\\b[^>]*>(.*?)</body>")
+            .find(this)
+            ?.groupValues
+            ?.get(1)
+            ?.trim()
+            ?: this
+    }
+
+    private fun htmlToText(html: String): String {
+        return html
+            .replace(Regex("(?is)<script.*?</script>"), "")
+            .replace(Regex("(?is)<style.*?</style>"), "")
+            .replace(Regex("(?i)<br\\s*/?>"), "\n")
+            .replace(Regex("(?i)</p\\s*>"), "\n\n")
+            .replace(Regex("(?i)</h[1-6]\\s*>"), "\n\n")
+            .replace(Regex("<[^>]+>"), " ")
+            .decodeEntities()
+            .replace(Regex("[ \\t\\x0B\\f\\r]+"), " ")
+            .replace(Regex(" *\\n *"), "\n")
+            .replace(Regex("\\n{3,}"), "\n\n")
+            .trim()
+    }
+
+    private fun String.decodeEntities(): String {
+        return replace("&nbsp;", " ")
+            .replace("&amp;", "&")
+            .replace("&lt;", "<")
+            .replace("&gt;", ">")
+            .replace("&quot;", "\"")
+            .replace("&#39;", "'")
+            .replace(Regex("&#x([0-9a-fA-F]+);")) { match ->
+                match.groupValues[1].toIntOrNull(16)?.toChar()?.toString().orEmpty()
+            }
+            .replace(Regex("&#(\\d+);")) { match ->
+                match.groupValues[1].toIntOrNull()?.toChar()?.toString().orEmpty()
+            }
+    }
+}

desktopApp/src/desktopMain/kotlin/com/aryan/reader/desktop/DesktopLibraryDatabase.kt

@@ -0,0 +1,205 @@
+package com.aryan.reader.desktop
+
+import com.aryan.reader.shared.BookItem
+import com.aryan.reader.shared.BookShelfRef
+import com.aryan.reader.shared.FileType
+import com.aryan.reader.shared.ShelfRecord
+import com.aryan.reader.shared.Tag
+import kotlinx.serialization.json.Json
+import kotlinx.serialization.json.JsonArray
+import kotlinx.serialization.json.JsonElement
+import kotlinx.serialization.json.JsonNull
+import kotlinx.serialization.json.JsonObject
+import kotlinx.serialization.json.JsonPrimitive
+import kotlinx.serialization.json.booleanOrNull
+import kotlinx.serialization.json.doubleOrNull
+import kotlinx.serialization.json.floatOrNull
+import kotlinx.serialization.json.jsonArray
+import kotlinx.serialization.json.jsonObject
+import kotlinx.serialization.json.jsonPrimitive
+import kotlinx.serialization.json.longOrNull
+import java.io.File
+
+data class DesktopLibrarySnapshot(
+    val books: List<BookItem> = emptyList(),
+    val shelfRecords: List<ShelfRecord> = emptyList(),
+    val shelfRefs: List<BookShelfRef> = emptyList(),
+    val tags: List<Tag> = emptyList()
+)
+
+class DesktopLibraryDatabase(
+    private val databaseFile: File = defaultDatabaseFile()
+) {
+    private val json = Json {
+        prettyPrint = true
+        ignoreUnknownKeys = true
+    }
+
+    fun load(): DesktopLibrarySnapshot {
+        if (!databaseFile.exists()) return DesktopLibrarySnapshot()
+        val root = runCatching {
+            json.parseToJsonElement(databaseFile.readText()).jsonObject
+        }.getOrNull() ?: return DesktopLibrarySnapshot()
+
+        return DesktopLibrarySnapshot(
+            books = root.array("books").mapNotNull { it.asBookItemOrNull() },
+            shelfRecords = root.array("shelves").mapNotNull { it.asShelfRecordOrNull() },
+            shelfRefs = root.array("bookShelfRefs").mapNotNull { it.asBookShelfRefOrNull() },
+            tags = root.array("tags").mapNotNull { it.asTagOrNull() }
+        )
+    }
+
+    fun save(snapshot: DesktopLibrarySnapshot) {
+        databaseFile.parentFile?.mkdirs()
+        val root = JsonObject(
+            mapOf(
+                "schemaVersion" to JsonPrimitive(1),
+                "books" to JsonArray(snapshot.books.map { it.toJsonObject() }),
+                "shelves" to JsonArray(snapshot.shelfRecords.map { it.toJsonObject() }),
+                "bookShelfRefs" to JsonArray(snapshot.shelfRefs.map { it.toJsonObject() }),
+                "tags" to JsonArray(snapshot.tags.map { it.toJsonObject() })
+            )
+        )
+        databaseFile.writeText(root.toString())
+    }
+
+    companion object {
+        fun defaultDatabaseFile(): File {
+            val baseDir = System.getenv("APPDATA")?.takeIf { it.isNotBlank() }
+                ?: File(System.getProperty("user.home"), "AppData/Roaming").absolutePath
+            return File(baseDir, "Episteme/library.json")
+        }
+    }
+}
+
+private fun JsonObject.array(name: String): List<JsonElement> {
+    return runCatching { this[name]?.jsonArray?.toList().orEmpty() }.getOrDefault(emptyList())
+}
+
+private fun JsonObject.string(name: String): String? {
+    return this[name]?.takeUnless { it is JsonNull }?.jsonPrimitive?.content
+}
+
+private fun JsonObject.long(name: String, fallback: Long = 0L): Long {
+    return this[name]?.jsonPrimitive?.longOrNull ?: fallback
+}
+
+private fun JsonObject.float(name: String): Float? {
+    return this[name]?.jsonPrimitive?.floatOrNull
+}
+
+private fun JsonObject.double(name: String): Double? {
+    return this[name]?.jsonPrimitive?.doubleOrNull
+}
+
+private fun JsonObject.boolean(name: String, fallback: Boolean): Boolean {
+    return this[name]?.jsonPrimitive?.booleanOrNull ?: fallback
+}
+
+private fun JsonElement.asBookItemOrNull(): BookItem? {
+    val obj = runCatching { jsonObject }.getOrNull() ?: return null
+    val id = obj.string("id") ?: return null
+    val displayName = obj.string("displayName") ?: return null
+    val type = obj.string("type")?.let { runCatching { FileType.valueOf(it) }.getOrNull() } ?: FileType.UNKNOWN
+    return BookItem(
+        id = id,
+        path = obj.string("path"),
+        type = type,
+        displayName = displayName,
+        timestamp = obj.long("timestamp"),
+        title = obj.string("title"),
+        author = obj.string("author"),
+        progressPercentage = obj.float("progressPercentage"),
+        isRecent = obj.boolean("isRecent", true),
+        fileSize = obj.long("fileSize"),
+        sourceFolder = obj.string("sourceFolder"),
+        seriesName = obj.string("seriesName"),
+        seriesIndex = obj.double("seriesIndex"),
+        tags = obj.array("tags").mapNotNull { it.asTagOrNull() }
+    )
+}
+
+private fun JsonElement.asShelfRecordOrNull(): ShelfRecord? {
+    val obj = runCatching { jsonObject }.getOrNull() ?: return null
+    return ShelfRecord(
+        id = obj.string("id") ?: return null,
+        name = obj.string("name") ?: return null,
+        isSmart = obj.boolean("isSmart", false),
+        smartRulesJson = obj.string("smartRulesJson")
+    )
+}
+
+private fun JsonElement.asBookShelfRefOrNull(): BookShelfRef? {
+    val obj = runCatching { jsonObject }.getOrNull() ?: return null
+    return BookShelfRef(
+        bookId = obj.string("bookId") ?: return null,
+        shelfId = obj.string("shelfId") ?: return null,
+        addedAt = obj.long("addedAt")
+    )
+}
+
+private fun JsonElement.asTagOrNull(): Tag? {
+    val obj = runCatching { jsonObject }.getOrNull() ?: return null
+    return Tag(
+        id = obj.string("id") ?: return null,
+        name = obj.string("name") ?: return null,
+        color = obj["color"]?.takeUnless { it is JsonNull }?.jsonPrimitive?.content?.toIntOrNull()
+    )
+}
+
+private fun BookItem.toJsonObject(): JsonObject {
+    return JsonObject(
+        mapOf(
+            "id" to JsonPrimitive(id),
+            "path" to path.asJson(),
+            "type" to JsonPrimitive(type.name),
+            "displayName" to JsonPrimitive(displayName),
+            "timestamp" to JsonPrimitive(timestamp),
+            "title" to title.asJson(),
+            "author" to author.asJson(),
+            "progressPercentage" to progressPercentage.asJson(),
+            "isRecent" to JsonPrimitive(isRecent),
+            "fileSize" to JsonPrimitive(fileSize),
+            "sourceFolder" to sourceFolder.asJson(),
+            "seriesName" to seriesName.asJson(),
+            "seriesIndex" to seriesIndex.asJson(),
+            "tags" to JsonArray(tags.map { it.toJsonObject() })
+        )
+    )
+}
+
+private fun ShelfRecord.toJsonObject(): JsonObject {
+    return JsonObject(
+        mapOf(
+            "id" to JsonPrimitive(id),
+            "name" to JsonPrimitive(name),
+            "isSmart" to JsonPrimitive(isSmart),
+            "smartRulesJson" to smartRulesJson.asJson()
+        )
+    )
+}
+
+private fun BookShelfRef.toJsonObject(): JsonObject {
+    return JsonObject(
+        mapOf(
+            "bookId" to JsonPrimitive(bookId),
+            "shelfId" to JsonPrimitive(shelfId),
+            "addedAt" to JsonPrimitive(addedAt)
+        )
+    )
+}
+
+private fun Tag.toJsonObject(): JsonObject {
+    return JsonObject(
+        mapOf(
+            "id" to JsonPrimitive(id),
+            "name" to JsonPrimitive(name),
+            "color" to color.asJson()
+        )
+    )
+}
+
+private fun String?.asJson(): JsonElement = this?.let { JsonPrimitive(it) } ?: JsonNull
+private fun Float?.asJson(): JsonElement = this?.let { JsonPrimitive(it) } ?: JsonNull
+private fun Double?.asJson(): JsonElement = this?.let { JsonPrimitive(it) } ?: JsonNull
+private fun Int?.asJson(): JsonElement = this?.let { JsonPrimitive(it) } ?: JsonNull

desktopApp/src/desktopMain/kotlin/com/aryan/reader/desktop/DesktopPdfium.kt

@@ -0,0 +1,239 @@
+package com.aryan.reader.desktop
+
+import androidx.compose.ui.graphics.ImageBitmap
+import androidx.compose.ui.graphics.toComposeImageBitmap
+import com.aryan.reader.shared.pdf.PdfZoomSpec
+import com.sun.jna.Library
+import com.sun.jna.Memory
+import com.sun.jna.Native
+import com.sun.jna.Pointer
+import java.awt.image.BufferedImage
+import java.io.File
+import java.nio.ByteOrder
+import kotlin.math.roundToInt
+
+data class DesktopPdfDocument(
+    val path: String,
+    val title: String,
+    val pageCount: Int,
+    val pageSizes: List<DesktopPdfPageSize>,
+    val textPages: List<String>
+) {
+    fun close() {
+        DesktopPdfium.closeDocument(path)
+    }
+}
+
+data class DesktopPdfPageSize(
+    val width: Float,
+    val height: Float
+)
+
+data class DesktopPdfPageRender(
+    val image: ImageBitmap,
+    val width: Int,
+    val height: Int
+)
+
+object DesktopPdfium {
+    private const val FPDF_ANNOT = 0x01
+    private const val FPDF_LCD_TEXT = 0x02
+    private const val FPDF_RENDER_NO_SMOOTHTEXT = 0x1000
+    private const val FPDF_BITMAP_BGRA = 4
+
+    private val pdfiumDll: File by lazy(::resolvePdfiumDll)
+    private val zoomSpec = PdfZoomSpec()
+    private val api: PdfiumLibrary by lazy {
+        require(pdfiumDll.exists()) {
+            "Missing Pdfium DLL. Expected pdfium-v8-win-x64 under third_party/pdfium/win-x64-v8/bin/pdfium.dll."
+        }
+        Native.load(pdfiumDll.absolutePath, PdfiumLibrary::class.java)
+    }
+
+    private var initialized = false
+    private val openDocuments = LinkedHashMap<String, Pointer>()
+
+    fun isAvailable(): Boolean = pdfiumDll.exists()
+
+    fun load(file: File, password: String? = null): DesktopPdfDocument {
+        initLibrary()
+        val document = api.FPDF_LoadDocument(file.absolutePath, password)
+            ?: error("Pdfium could not open ${file.name}. It may be encrypted or unsupported.")
+        val pageCount = api.FPDF_GetPageCount(document)
+        openDocuments[file.absolutePath] = document
+
+        val pageSizes = (0 until pageCount).map { pageIndex ->
+            loadPage(document, pageIndex).usePointer { page ->
+                DesktopPdfPageSize(
+                    width = api.FPDF_GetPageWidthF(page),
+                    height = api.FPDF_GetPageHeightF(page)
+                )
+            }
+        }
+
+        val textPages = (0 until pageCount).map { pageIndex ->
+            extractPageText(document, pageIndex)
+        }
+
+        return DesktopPdfDocument(
+            path = file.absolutePath,
+            title = file.nameWithoutExtension,
+            pageCount = pageCount,
+            pageSizes = pageSizes,
+            textPages = textPages
+        )
+    }
+
+    fun closeDocument(path: String) {
+        openDocuments.remove(path)?.let(api::FPDF_CloseDocument)
+    }
+
+    fun renderPage(
+        document: DesktopPdfDocument,
+        pageIndex: Int,
+        scale: Float,
+        renderAnnotations: Boolean = true
+    ): DesktopPdfPageRender {
+        val nativeDocument = openDocuments[document.path] ?: error("PDF document is not open.")
+        val pageSize = document.pageSizes.getOrNull(pageIndex) ?: error("Invalid PDF page index $pageIndex.")
+        val safeScale = zoomSpec.safeRenderScale(pageSize.width, pageSize.height, scale)
+        val width = (pageSize.width * safeScale).roundToInt().coerceAtLeast(1)
+        val height = (pageSize.height * safeScale).roundToInt().coerceAtLeast(1)
+        val stride = width * 4
+        val memory = Memory((stride * height).toLong())
+        memory.clear(memory.size())
+
+        val bitmap = api.FPDFBitmap_CreateEx(width, height, FPDF_BITMAP_BGRA, memory, stride)
+            ?: error("Pdfium could not allocate render bitmap.")
+
+        try {
+            api.FPDFBitmap_FillRect(bitmap, 0, 0, width, height, -1)
+            loadPage(nativeDocument, pageIndex).usePointer { page ->
+                val flags = FPDF_LCD_TEXT or
+                    (if (renderAnnotations) FPDF_ANNOT else FPDF_RENDER_NO_SMOOTHTEXT)
+                api.FPDF_RenderPageBitmap(bitmap, page, 0, 0, width, height, 0, flags)
+            }
+            return DesktopPdfPageRender(
+                image = memory.toBufferedImage(width, height, stride).toComposeImageBitmap(),
+                width = width,
+                height = height
+            )
+        } finally {
+            api.FPDFBitmap_Destroy(bitmap)
+        }
+    }
+
+    private fun extractPageText(document: Pointer, pageIndex: Int): String {
+        return runCatching {
+            loadPage(document, pageIndex).usePointer { page ->
+                val textPage = api.FPDFText_LoadPage(page) ?: return@usePointer ""
+                try {
+                    val charCount = api.FPDFText_CountChars(textPage)
+                    if (charCount <= 0) return@usePointer ""
+                    val buffer = Memory(((charCount + 1) * 2L))
+                    val written = api.FPDFText_GetText(textPage, 0, charCount, buffer)
+                    if (written <= 0) {
+                        ""
+                    } else {
+                        buffer.getCharArray(0, written).concatToString().trimEnd('\u0000')
+                    }
+                } finally {
+                    api.FPDFText_ClosePage(textPage)
+                }
+            }
+        }.getOrDefault("")
+    }
+
+    private fun loadPage(document: Pointer, pageIndex: Int): PointerResource {
+        val page = api.FPDF_LoadPage(document, pageIndex)
+            ?: error("Pdfium could not open page ${pageIndex + 1}.")
+        return PointerResource(page, api::FPDF_ClosePage)
+    }
+
+    private fun initLibrary() {
+        if (!initialized) {
+            api.FPDF_InitLibrary()
+            initialized = true
+        }
+    }
+
+    private fun resolvePdfiumDll(): File {
+        val overridePath = System.getProperty("reader.pdfium.dll")
+            ?: System.getenv("READER_PDFIUM_DLL")
+        if (!overridePath.isNullOrBlank()) {
+            return File(overridePath).absoluteFile
+        }
+
+        val relativePath = listOf("third_party", "pdfium", "win-x64-v8", "bin", "pdfium.dll")
+            .joinToString(File.separator)
+        val roots = generateSequence(File(System.getProperty("user.dir")).absoluteFile) { it.parentFile }
+            .take(6)
+            .toList()
+
+        return roots
+            .map { File(it, relativePath).absoluteFile }
+            .firstOrNull { it.exists() }
+            ?: File(File(System.getProperty("user.dir")).absoluteFile, relativePath).absoluteFile
+    }
+
+    private fun Memory.toBufferedImage(width: Int, height: Int, stride: Int): BufferedImage {
+        val image = BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB)
+        val buffer = getByteBuffer(0, size()).order(ByteOrder.LITTLE_ENDIAN)
+        val pixels = IntArray(width * height)
+        for (y in 0 until height) {
+            buffer.position(y * stride)
+            for (x in 0 until width) {
+                val b = buffer.get().toInt() and 0xFF
+                val g = buffer.get().toInt() and 0xFF
+                val r = buffer.get().toInt() and 0xFF
+                val a = buffer.get().toInt() and 0xFF
+                pixels[y * width + x] = (a shl 24) or (r shl 16) or (g shl 8) or b
+            }
+        }
+        image.setRGB(0, 0, width, height, pixels, 0, width)
+        return image
+    }
+
+    private class PointerResource(
+        private val pointer: Pointer,
+        private val closer: (Pointer) -> Unit
+    ) {
+        fun <T> usePointer(block: (Pointer) -> T): T {
+            try {
+                return block(pointer)
+            } finally {
+                closer(pointer)
+            }
+        }
+    }
+
+    @Suppress("FunctionName")
+    private interface PdfiumLibrary : Library {
+        fun FPDF_InitLibrary()
+        fun FPDF_LoadDocument(filePath: String, password: String?): Pointer?
+        fun FPDF_CloseDocument(document: Pointer)
+        fun FPDF_GetPageCount(document: Pointer): Int
+        fun FPDF_LoadPage(document: Pointer, pageIndex: Int): Pointer?
+        fun FPDF_ClosePage(page: Pointer)
+        fun FPDF_GetPageWidthF(page: Pointer): Float
+        fun FPDF_GetPageHeightF(page: Pointer): Float
+        fun FPDFBitmap_CreateEx(width: Int, height: Int, format: Int, firstScan: Pointer, stride: Int): Pointer?
+        fun FPDFBitmap_FillRect(bitmap: Pointer, left: Int, top: Int, width: Int, height: Int, color: Int)
+        fun FPDFBitmap_Destroy(bitmap: Pointer)
+        fun FPDF_RenderPageBitmap(
+            bitmap: Pointer,
+            page: Pointer,
+            startX: Int,
+            startY: Int,
+            sizeX: Int,
+            sizeY: Int,
+            rotate: Int,
+            flags: Int
+        )
+
+        fun FPDFText_LoadPage(page: Pointer): Pointer?
+        fun FPDFText_ClosePage(textPage: Pointer)
+        fun FPDFText_CountChars(textPage: Pointer): Int
+        fun FPDFText_GetText(textPage: Pointer, startIndex: Int, count: Int, result: Pointer): Int
+    }
+}

gradle/libs.versions.toml

@@ -21,7 +21,7 @@ androidxAnnotationJvm = "1.9.1"
 androidxTestRunner = "1.6.2"
 material3WindowSizeClassAndroid = "1.3.2"
 credentials = "1.5.0"
-
+composeMultiplatform = "1.8.2"
 
 [libraries]
 androidx-core-ktx = { group = "androidx.core", name = "core-ktx", version.ref = "coreKtx" }
@@ -59,8 +59,10 @@ androidx-credentials = { group = "androidx.credentials", name = "credentials", v
 [plugins]
 android-application = { id = "com.android.application", version.ref = "agp" }
 kotlin-android = { id = "org.jetbrains.kotlin.android", version.ref = "kotlin" }
+kotlin-multiplatform = { id = "org.jetbrains.kotlin.multiplatform", version.ref = "kotlin" }
 kotlin-compose = { id = "org.jetbrains.kotlin.plugin.compose", version.ref = "kotlin" }
 kotlin-ksp = { id = "com.google.devtools.ksp", version = "2.3.2" }
+compose-multiplatform = { id = "org.jetbrains.compose", version.ref = "composeMultiplatform" }
 
 # Add plugins required by pdfiumandroid
 android-library = { id = "com.android.library", version.ref = "agp" }

settings.gradle.kts

@@ -17,8 +17,12 @@ dependencyResolutionManagement {
         google()
         mavenCentral()
         maven("https://jitpack.io")
+        maven("https://jogamp.org/deployment/maven")
+        maven("https.jitpack.io")
     }
 }
 
 rootProject.name = "Reader"
 include(":app")
+include(":shared")
+include(":desktopApp")

shared/build.gradle.kts

@@ -0,0 +1,49 @@
+plugins {
+    alias(libs.plugins.kotlin.multiplatform)
+    id("com.android.library")
+    alias(libs.plugins.kotlin.compose)
+    alias(libs.plugins.compose.multiplatform)
+    id("org.jetbrains.kotlin.plugin.serialization") version "2.1.20"
+}
+
+kotlin {
+    androidTarget()
+    jvm("desktop")
+    jvmToolchain(21)
+
+    sourceSets {
+        val commonMain by getting
+        val androidMain by getting
+        val desktopMain by getting
+        val readerJvmMain by creating {
+            dependsOn(commonMain)
+            dependencies {
+                implementation("org.jsoup:jsoup:1.17.2")
+            }
+        }
+        androidMain.dependsOn(readerJvmMain)
+        desktopMain.dependsOn(readerJvmMain)
+
+        commonMain.dependencies {
+            implementation(compose.foundation)
+            implementation(compose.material3)
+            implementation(compose.materialIconsExtended)
+            implementation(compose.ui)
+            implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.8.1")
+            implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.7.3")
+            implementation("org.jetbrains.kotlinx:kotlinx-serialization-protobuf:1.7.3")
+        }
+        commonTest.dependencies {
+            implementation(kotlin("test"))
+        }
+    }
+}
+
+android {
+    namespace = "com.aryan.reader.shared"
+    compileSdk = 36
+
+    defaultConfig {
+        minSdk = 26
+    }
+}

shared/src/androidMain/kotlin/com/aryan/reader/shared/Platform.android.kt

@@ -0,0 +1,3 @@
+package com.aryan.reader.shared
+
+actual fun currentTimestamp(): Long = System.currentTimeMillis()

shared/src/commonMain/kotlin/com/aryan/reader/paginatedreader/CssParser.kt

@@ -21,7 +21,6 @@ package com.aryan.reader.paginatedreader
 
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.isSpecified
-import androidx.compose.ui.graphics.toArgb
 import androidx.compose.ui.text.ParagraphStyle
 import androidx.compose.ui.text.SpanStyle
 import androidx.compose.ui.text.font.FontStyle
@@ -35,23 +34,45 @@ import androidx.compose.ui.unit.TextUnit
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.em
 import androidx.compose.ui.unit.isSpecified
-import timber.log.Timber
-import java.io.File
-import java.util.regex.Pattern
 import kotlin.math.roundToInt
 
 private const val IMPORTANT_SPECIFICITY_BOOST = 10_000
+
+private object ReaderCssLog {
+    fun d(@Suppress("UNUSED_PARAMETER") message: String) = Unit
+    fun w(@Suppress("UNUSED_PARAMETER") message: String) = Unit
+    fun w(@Suppress("UNUSED_PARAMETER") throwable: Throwable, @Suppress("UNUSED_PARAMETER") message: String) = Unit
+    fun e(@Suppress("UNUSED_PARAMETER") throwable: Throwable, @Suppress("UNUSED_PARAMETER") message: String) = Unit
+}
+
 private fun Color.luminance(): Float {
     if (!this.isSpecified) return 0f
     return (0.299f * red + 0.587f * green + 0.114f * blue)
 }
 
+private fun resolveCssRelativePath(cssPath: String, rawSrc: String): String {
+    if (rawSrc.startsWith("/") || rawSrc.contains("://")) return rawSrc
+    val normalizedBase = cssPath.replace('\\', '/').substringBeforeLast('/', "")
+    val parts = ArrayDeque<String>()
+    (if (normalizedBase.isBlank()) rawSrc else "$normalizedBase/$rawSrc")
+        .replace('\\', '/')
+        .split('/')
+        .forEach { part ->
+            when (part) {
+                "", "." -> Unit
+                ".." -> if (parts.isNotEmpty()) parts.removeLast()
+                else -> parts.addLast(part)
+            }
+        }
+    return parts.joinToString("/")
+}
+
 object CssParser {
     private val FONT_FACE_REGEX = "@font-face\\s*\\{([^}]+)\\}".toRegex(RegexOption.DOT_MATCHES_ALL)
     private val URL_REGEX = "url\\((['\"]?)(.*?)\\1\\)".toRegex()
-    private val ID_SELECTOR_PATTERN = Pattern.compile("#[^\\s,]+")
-    private val CLASS_ATTRIBUTE_SELECTOR_PATTERN = Pattern.compile("\\.[^\\s,]+|\\[[^]]+]|:(?!:)[^\\s,]+")
-    private val TYPE_PSEUDO_ELEMENT_SELECTOR_PATTERN = Pattern.compile("(?<![.#\\[])\\b[a-zA-Z-]+|::[a-zA-Z-]+")
+    private val ID_SELECTOR_REGEX = Regex("#[^\\s,]+")
+    private val CLASS_ATTRIBUTE_SELECTOR_REGEX = Regex("\\.[^\\s,]+|\\[[^]]+]|:(?!:)[^\\s,]+")
+    private val TYPE_PSEUDO_ELEMENT_SELECTOR_REGEX = Regex("(?<![.#\\[])\\b[a-zA-Z-]+|::[a-zA-Z-]+")
     private data class FontSource(val url: String, val format: String?)
 
     // Regex to identify simple, single-part selectors for fast categorization
@@ -65,7 +86,7 @@ object CssParser {
         "thick" to 5.dp
     )
 
-    internal fun adaptColorForTheme(
+    fun adaptColorForTheme(
         color: Color,
         isDarkTheme: Boolean,
         isBackground: Boolean,
@@ -113,16 +134,7 @@ object CssParser {
                 return color
             }
 
-            val hsl = FloatArray(3)
-            androidx.core.graphics.ColorUtils.colorToHSL(color.toArgb(), hsl)
-
-            if (bgLuminance < 0.5f) {
-                hsl[2] = hsl[2].coerceAtLeast(0.7f)
-            } else {
-                hsl[2] = hsl[2].coerceAtMost(0.3f)
-            }
-
-            return Color(androidx.core.graphics.ColorUtils.HSLToColor(hsl))
+            return themeText.takeIf { it.isSpecified } ?: color
         }
     }
 
@@ -143,7 +155,7 @@ object CssParser {
                 reassembled = true
             }
             if (reassembled) {
-                Timber.d("Reassembled declaration. Original: '$originalCurrent'. Final: '$current'")
+                ReaderCssLog.d("Reassembled declaration. Original: '$originalCurrent'. Final: '$current'")
             }
             result.add(current)
         }
@@ -151,21 +163,9 @@ object CssParser {
     }
 
     private fun calculateSpecificity(selector: String): Int {
-        val ids = ID_SELECTOR_PATTERN.matcher(selector).run {
-            var count = 0
-            while (find()) count++
-            count
-        }
-        val classesAndAttributes = CLASS_ATTRIBUTE_SELECTOR_PATTERN.matcher(selector).run {
-            var count = 0
-            while (find()) count++
-            count
-        }
-        val elementsAndPseudos = TYPE_PSEUDO_ELEMENT_SELECTOR_PATTERN.matcher(selector).run {
-            var count = 0
-            while (find()) count++
-            count
-        }
+        val ids = ID_SELECTOR_REGEX.findAll(selector).count()
+        val classesAndAttributes = CLASS_ATTRIBUTE_SELECTOR_REGEX.findAll(selector).count()
+        val elementsAndPseudos = TYPE_PSEUDO_ELEMENT_SELECTOR_REGEX.findAll(selector).count()
         val specificity = ids * 100 + classesAndAttributes * 10 + elementsAndPseudos
         return specificity
     }
@@ -200,13 +200,13 @@ object CssParser {
         }
         cleanedCss = mediaQueryRegex.replace(cleanedCss, "")
 
-        Timber.d("CssParser: Checking for @font-face rules...")
+        ReaderCssLog.d("CssParser: Checking for @font-face rules...")
         val fontFaceMatches = FONT_FACE_REGEX.findAll(cleanedCss)
         if (!fontFaceMatches.any()) {
-            Timber.d("CssParser: No @font-face rules found by regex.")
+            ReaderCssLog.d("CssParser: No @font-face rules found by regex.")
         }
         fontFaceMatches.forEach { match ->
-            Timber.d("CssParser: Found a @font-face block. Parsing its properties.")
+            ReaderCssLog.d("CssParser: Found a @font-face block. Parsing its properties.")
             val properties = match.groupValues[1]
             parseFontFace(properties, cssPath)?.let { fontFaces.add(it) }
         }
@@ -269,10 +269,10 @@ object CssParser {
 
         val fontFamily = propsMap["font-family"]?.removeSurrounding("\"")?.removeSurrounding("'")?.lowercase()
         val srcString = propsMap["src"]
-        Timber.d("Parsing font-face for family: $fontFamily. Raw src string: $srcString")
+        ReaderCssLog.d("Parsing font-face for family: $fontFamily. Raw src string: $srcString")
 
         if (fontFamily == null || srcString == null) {
-            Timber.w("Incomplete @font-face rule: missing font-family or src.")
+            ReaderCssLog.w("Incomplete @font-face rule: missing font-family or src.")
             return null
         }
 
@@ -280,25 +280,25 @@ object CssParser {
 
         val sources = srcString.split(Regex(",(?=\\s*url\\()")).mapNotNull { part ->
             val trimmedPart = part.trim()
-            Timber.d("Processing src part: '$trimmedPart'")
+            ReaderCssLog.d("Processing src part: '$trimmedPart'")
 
             urlWithFormatRegex.find(trimmedPart)?.let {
-                Timber.d("Matched url with format(). URL: ${it.groupValues[2]}, Format: ${it.groupValues[4]}")
+                ReaderCssLog.d("Matched url with format(). URL: ${it.groupValues[2]}, Format: ${it.groupValues[4]}")
                 FontSource(url = it.groupValues[2], format = it.groupValues[4].lowercase().removeSurrounding("'"))
             } ?: URL_REGEX.find(trimmedPart)?.let {
                 val url = it.groupValues[2]
-                Timber.d("Matched url() only. URL: '$url'")
+                ReaderCssLog.d("Matched url() only. URL: '$url'")
                 val format = when {
                     url.startsWith("data:", ignoreCase = true) -> {
                         val mediaType = url.substringAfter("data:").substringBefore(';')
-                        Timber.d("Data URI detected. Media type: '$mediaType'")
+                        ReaderCssLog.d("Data URI detected. Media type: '$mediaType'")
                         when {
                             mediaType.contains("opentype") -> "opentype"
                             mediaType.contains("truetype") -> "truetype"
                             mediaType.contains("woff2") -> "woff2"
                             mediaType.contains("woff") -> "woff"
                             else -> {
-                                Timber.w("Unknown data URI media type: $mediaType")
+                                ReaderCssLog.w("Unknown data URI media type: $mediaType")
                                 null
                             }
                         }
@@ -308,11 +308,11 @@ object CssParser {
                     url.endsWith(".otf", ignoreCase = true) -> "opentype"
                     url.endsWith(".ttf", ignoreCase = true) -> "truetype"
                     else -> {
-                        Timber.w("Could not determine format from URL: $url")
+                        ReaderCssLog.w("Could not determine format from URL: $url")
                         null
                     }
                 }
-                Timber.d("Determined format: '$format'")
+                ReaderCssLog.d("Determined format: '$format'")
                 if (format != null) {
                     FontSource(url = url, format = format)
                 } else {
@@ -322,7 +322,7 @@ object CssParser {
         }
 
         if (sources.isEmpty()) {
-            Timber.w("Could not parse any valid source from @font-face src: $srcString")
+            ReaderCssLog.w("Could not parse any valid source from @font-face src: $srcString")
             return null
         }
 
@@ -337,14 +337,13 @@ object CssParser {
         }!!
 
         val rawSrc = preferredSource.url
-        Timber.d("Selected font source for '$fontFamily': '${preferredSource.url}' with format '${preferredSource.format}'")
+        ReaderCssLog.d("Selected font source for '$fontFamily': '${preferredSource.url}' with format '${preferredSource.format}'")
 
         val finalSrc = if (cssPath != null && !rawSrc.startsWith("data:")) {
             try {
-                val cssParentDir = File(cssPath).parent ?: ""
-                File(cssParentDir, rawSrc).normalize().path
+                resolveCssRelativePath(cssPath, rawSrc)
             } catch (e: Exception) {
-                Timber.e(e, "Could not resolve font path for src '$rawSrc' in css '$cssPath'")
+                ReaderCssLog.e(e, "Could not resolve font path for src '$rawSrc' in css '$cssPath'")
                 rawSrc // Fallback to the raw path on error
             }
         } else {
@@ -1038,10 +1037,20 @@ object CssParser {
                         val r = (colorLong and 0xF00) shr 8
                         val g = (colorLong and 0x0F0) shr 4
                         val b = colorLong and 0x00F
-                        Color(Color(0xFF000000 or ((r * 17) shl 16) or ((g * 17) shl 8) or (b * 17)).toArgb())
+                        Color((r * 17).toInt(), (g * 17).toInt(), (b * 17).toInt(), 255)
                     }
-                    6 -> Color(Color(0xFF000000 or colorLong).toArgb()) // #RRGGBB
-                    8 -> Color(Color(colorLong).toArgb()) // #AARRGGBB
+                    6 -> Color(
+                        ((colorLong shr 16) and 0xFF).toInt(),
+                        ((colorLong shr 8) and 0xFF).toInt(),
+                        (colorLong and 0xFF).toInt(),
+                        255
+                    ) // #RRGGBB
+                    8 -> Color(
+                        ((colorLong shr 16) and 0xFF).toInt(),
+                        ((colorLong shr 8) and 0xFF).toInt(),
+                        (colorLong and 0xFF).toInt(),
+                        ((colorLong shr 24) and 0xFF).toInt()
+                    ) // #AARRGGBB
                     else -> null
                 }
             }

shared/src/commonMain/kotlin/com/aryan/reader/paginatedreader/FontFamilyMapper.kt

@@ -0,0 +1,39 @@
+package com.aryan.reader.paginatedreader
+
+import androidx.compose.ui.text.font.FontFamily
+
+/**
+ * Shared mapper for generic CSS font-family names.
+ *
+ * Platform-specific font loaders can still resolve embedded/custom font files and add their own
+ * FontFamily instances, but generic CSS families should behave consistently everywhere.
+ */
+object FontFamilyMapper {
+    private val genericFontMap = mapOf(
+        "serif" to FontFamily.Serif,
+        "sans-serif" to FontFamily.SansSerif,
+        "monospace" to FontFamily.Monospace,
+        "cursive" to FontFamily.Cursive,
+        "default" to FontFamily.Default,
+        "system-ui" to FontFamily.Default,
+        "ui-sans-serif" to FontFamily.Default,
+        "ui-serif" to FontFamily.Default,
+        "ui-monospace" to FontFamily.Default,
+        "ui-rounded" to FontFamily.Default
+    )
+
+    fun nameToFontFamily(name: String): FontFamily? {
+        return genericFontMap[name.trim().lowercase()]
+    }
+
+    fun fontFamilyToName(fontFamily: FontFamily): String? {
+        return when (fontFamily) {
+            FontFamily.Serif -> "serif"
+            FontFamily.SansSerif -> "sans-serif"
+            FontFamily.Monospace -> "monospace"
+            FontFamily.Cursive -> "cursive"
+            FontFamily.Default -> "default"
+            else -> null
+        }
+    }
+}