Epub improvements (#160)

* Improved navigation and search result highlighting in the EPUB reader

* refactor: implement JIT chunk restoration for robust navigation

- Fixes search and bookmark navigation failing in same-chapter transitions.
- Introduced JIT (Just-in-Time) HTML restoration in `epub_reader.js` to
  re-populate virtualized chunks before CFI resolution or search scrolling.
- Synchronized search highlighting and user highlights within
  newly-restored chunk segments.
- Improved search navigation accuracy by mapping occurrences to
  relative chunk indices.

* Implemented a custom text selection engine for the paginated EPUB reader to support cross-page selection and improved handle interaction.

* Implemented management of external file behavior and improved library filtering.

* Added support for toolbar customization in the EPUB reader.

* Added support for toolbar customization in the PDF reader.

* fix: rendering during auto-scroll and navigation on long pages

* Added a "Scroll to Top" feature to the auto-scroll controls in both EPUB and PDF readers.

app/src/main/assets/epub_reader.js

@@ -774,15 +774,16 @@
         document.addEventListener("DOMContentLoaded", initializeReaderContent);
     }
 
+    window.CURRENT_SEARCH_QUERY = "";
+
     window.clearSearchHighlights = function () {
+        window.CURRENT_SEARCH_QUERY = "";
         document.querySelectorAll("mark.search-highlight").forEach(function (el) {
             var parent = el.parentNode;
-
             if (parent) {
                 while (el.firstChild) {
                     parent.insertBefore(el.firstChild, el);
                 }
-
                 parent.removeChild(el);
                 parent.normalize();
             }
@@ -792,10 +793,12 @@
 
     window.highlightAllOccurrences = function (query) {
         window.clearSearchHighlights();
+        window.CURRENT_SEARCH_QUERY = query;
+
         if (!query || query.length < 2) return "JS: Query too short for highlighting.";
 
         var walker = document.createTreeWalker(document.body, NodeFilter.SHOW_TEXT, null, false);
-        var nodesToModify = [];
+        var nodesToModify =[];
 
         while ((node = walker.nextNode())) {
             if (node.nodeValue.toLowerCase().includes(query.toLowerCase())) {
@@ -811,11 +814,9 @@
                 tempDiv.innerHTML = textNode.nodeValue.replace(regex, '<mark class="search-highlight">$1</mark>');
 
                 var parent = textNode.parentNode;
-
                 while (tempDiv.firstChild) {
                     parent.insertBefore(tempDiv.firstChild, textNode);
                 }
-
                 parent.removeChild(textNode);
             }
         });
@@ -823,17 +824,37 @@
         return "JS: Highlighted " + document.querySelectorAll("mark.search-highlight").length + " occurrences.";
     };
 
-    window.scrollToOccurrence = function (index) {
+    window.scrollToChunkOccurrence = function (chunkIndex, relativeIndex) {
-        var highlights = document.querySelectorAll("mark.search-highlight");
+        console.log("NavDiag: scrollToChunkOccurrence chunk=" + chunkIndex + ", relativeIdx=" + relativeIndex);
+        var chunkDiv = document.querySelector(`.chunk-container[data-chunk-index='${chunkIndex}']`);
 
-        if (highlights && index >= 0 && index < highlights.length) {
+        if (chunkDiv) {
-            var element = highlights[index];
+            let wasEmpty = false;
 
-            element.scrollIntoView({ behavior: "auto", block: "center", inline: "nearest" });
+            if (chunkDiv.innerHTML === "" && window.virtualization && window.virtualization.chunksData[chunkIndex]) {
-            return "JS: Scrolled to occurrence " + index;
+                console.log("NavDiag: Chunk was empty, restoring content before scrolling.");
+                chunkDiv.innerHTML = window.virtualization.chunksData[chunkIndex];
+                chunkDiv.style.height = "";
+                wasEmpty = true;
             }
 
-        return "JS: Occurrence " + index + " not found.";
+            var highlights = chunkDiv.querySelectorAll("mark.search-highlight");
+
+            if ((wasEmpty || highlights.length === 0) && window.CURRENT_SEARCH_QUERY) {
+                window.highlightAllOccurrences(window.CURRENT_SEARCH_QUERY);
+                highlights = chunkDiv.querySelectorAll("mark.search-highlight");
+            }
+
+            if (highlights && highlights.length > 0) {
+                var targetIdx = (relativeIndex >= 0 && relativeIndex < highlights.length) ? relativeIndex : 0;
+                highlights[targetIdx].scrollIntoView({ behavior: "auto", block: "center", inline: "nearest" });
+                return "JS: Scrolled to relative occurrence " + targetIdx + " in chunk " + chunkIndex;
+            } else {
+                chunkDiv.scrollIntoView({ behavior: "auto", block: "center" });
+                return "JS: No highlights in chunk, scrolled to chunk center.";
+            }
+        }
+        return "JS: Chunk " + chunkIndex + " not found.";
     };
 
     window.removeHighlight = function () {
@@ -1429,6 +1450,15 @@
 
                 let chunkElement = currentNode.querySelector(`.chunk-container[data-chunk-index="${chunkIndex}"]`);
                 if (chunkElement) {
+                    if (chunkElement.innerHTML === "" && window.virtualization && window.virtualization.chunksData[chunkIndex]) {
+                        console.log("CFI_DIAGNOSIS: Chunk " + chunkIndex + " was empty, restoring content for CFI resolution.");
+                        chunkElement.innerHTML = window.virtualization.chunksData[chunkIndex];
+                        chunkElement.style.height = "";
+                        if (window.CURRENT_HIGHLIGHTS) {
+                            window.HighlightBridgeHelper.restoreHighlights(window.CURRENT_HIGHLIGHTS);
+                        }
+                    }
+
                     let elementsInChunk = Array.from(chunkElement.childNodes).filter(n => n.nodeType === Node.ELEMENT_NODE);
                     if (indexInChunk >= 0 && indexInChunk < elementsInChunk.length) {
                         currentNode = elementsInChunk[indexInChunk];
@@ -1649,7 +1679,7 @@
             cleanCfi = cfi.substring(cfi.indexOf('@') + 1);
         }
 
-        console.log("PosSaveDiag: JS scrollToCfi called with cleanCfi=" + cleanCfi);
+        console.log("NavDiag: JS scrollToCfi called with cleanCfi=" + cleanCfi);
 
         if (!cleanCfi || !cleanCfi.startsWith('/')) {
             if (window.CfiBridge && window.CfiBridge.onScrollFinished) {
@@ -1719,6 +1749,7 @@
                     }
 
                     if (Math.abs(window.scrollY - targetScrollY) > 1) {
+                        console.log("NavDiag: Scrolling to targetY=" + targetScrollY);
                         window.scrollTo({ top: targetScrollY, behavior: 'auto' });
                     }
 
@@ -1947,6 +1978,9 @@
                                 if (window.CURRENT_HIGHLIGHTS) {
                                     window.HighlightBridgeHelper.restoreHighlights(window.CURRENT_HIGHLIGHTS);
                                 }
+                                if (window.CURRENT_SEARCH_QUERY) {
+                                    window.highlightAllOccurrences(window.CURRENT_SEARCH_QUERY);
+                                }
                             }
                         } else {
                             if (div.innerHTML !== "") {
@@ -2005,6 +2039,10 @@
                 if (window.CURRENT_HIGHLIGHTS) {
                     window.HighlightBridgeHelper.restoreHighlights(window.CURRENT_HIGHLIGHTS);
                 }
+
+                if (window.CURRENT_SEARCH_QUERY) {
+                    window.highlightAllOccurrences(window.CURRENT_SEARCH_QUERY);
+                }
             }
 
             if (window.checkImagesForDiagnosis) {

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

@@ -70,6 +70,7 @@ import androidx.compose.material3.AlertDialog
 import androidx.compose.material3.Badge
 import androidx.compose.material3.BadgedBox
 import androidx.compose.material3.ButtonDefaults
+import androidx.compose.material3.Checkbox
 import androidx.compose.material3.CircularProgressIndicator
 import androidx.compose.material3.DrawerValue
 import androidx.compose.material3.DropdownMenu
@@ -83,6 +84,7 @@ import androidx.compose.material3.ModalDrawerSheet
 import androidx.compose.material3.ModalNavigationDrawer
 import androidx.compose.material3.NavigationDrawerItem
 import androidx.compose.material3.OutlinedCard
+import androidx.compose.material3.RadioButton
 import androidx.compose.material3.Scaffold
 import androidx.compose.material3.SnackbarHost
 import androidx.compose.material3.SnackbarHostState
@@ -163,6 +165,7 @@ fun HomeScreen(
         var showAboutDialog by remember { mutableStateOf(false) }
         var showInfoDialog by remember { mutableStateOf(false) }
         var itemForInfoDialog by remember { mutableStateOf<RecentFileItem?>(null) }
+        var showBehaviorDialog by remember { mutableStateOf(false) }
 
         var showClearBookCacheDialog by remember { mutableStateOf(false) }
         var showClearReflowCacheDialog by remember { mutableStateOf(false) }
@@ -308,7 +311,8 @@ fun HomeScreen(
                                 onFolderSyncToggle = viewModel::setFolderSyncEnabled,
                                 onClearReflowCache = { showClearReflowCacheDialog = true },
                                 onRecentFilesLimitChange = viewModel::setRecentFilesLimit,
-                                onTabsToggle = viewModel::setTabsEnabled
+                                onTabsToggle = viewModel::setTabsEnabled,
+                                onExternalFileBehaviorClick = { showBehaviorDialog = true }
                             )
                         } else {
                             ContextualTopAppBar(
@@ -443,6 +447,20 @@ fun HomeScreen(
                             onDismiss = { showClearReflowCacheDialog = false }
                         )
                     }
+                    if (uiState.showExternalFileSavePromptFor != null) {
+                        ExternalFileSaveDialog(
+                            onConfirm = { keep, dontAskAgain ->
+                                viewModel.handleExternalFilePrompt(uiState.showExternalFileSavePromptFor!!, keep, dontAskAgain)
+                            }
+                        )
+                    }
+                    if (showBehaviorDialog) {
+                        ExternalFileBehaviorDialog(
+                            currentBehavior = uiState.externalFileBehavior,
+                            onDismiss = { showBehaviorDialog = false },
+                            onSelect = { viewModel.setExternalFileBehavior(it) }
+                        )
+                    }
                 }
             }
             if (showAboutDialog) {
@@ -758,7 +776,8 @@ fun DefaultTopAppBar(
     onShowDeviceManagement: () -> Unit,
     onFolderSyncToggle: (Boolean) -> Unit,
     onRecentFilesLimitChange: (Int) -> Unit,
-    onTabsToggle: (Boolean) -> Unit
+    onTabsToggle: (Boolean) -> Unit,
+    onExternalFileBehaviorClick: () -> Unit
 ) {
     var showOptionsMenu by remember { mutableStateOf(false) }
     var showLimitMenu by remember { mutableStateOf(false) }
@@ -822,6 +841,11 @@ fun DefaultTopAppBar(
                     }
                 })
 
+                DropdownMenuItem(text = { Text(stringResource(R.string.options_external_file_behavior)) }, onClick = {
+                    onExternalFileBehaviorClick()
+                    showOptionsMenu = false
+                })
+
                 HorizontalDivider()
                 DropdownMenuItem(text = { Text(stringResource(R.string.options_clear_book_cache)) }, onClick = {
                     onClearCache()
@@ -1285,3 +1309,77 @@ fun DangerousFolderActionDialog(
         }
     )
 }
+
+@Composable
+fun ExternalFileSaveDialog(
+    onConfirm: (keep: Boolean, dontAskAgain: Boolean) -> Unit
+) {
+    var dontAsk by remember { mutableStateOf(false) }
+
+    AlertDialog(
+        onDismissRequest = { },
+        properties = androidx.compose.ui.window.DialogProperties(dismissOnBackPress = false, dismissOnClickOutside = false),
+        title = { Text(stringResource(R.string.external_file_prompt_title)) },
+        text = {
+            Column {
+                Text(stringResource(R.string.external_file_prompt_desc))
+                Spacer(modifier = Modifier.height(16.dp))
+                Row(
+                    verticalAlignment = Alignment.CenterVertically,
+                    modifier = Modifier
+                        .fillMaxWidth()
+                        .clickable { dontAsk = !dontAsk }
+                ) {
+                    Checkbox(checked = dontAsk, onCheckedChange = { dontAsk = it })
+                    Text(stringResource(R.string.external_file_dont_ask))
+                }
+            }
+        },
+        confirmButton = {
+            TextButton(onClick = { onConfirm(true, dontAsk) }) {
+                Text(stringResource(R.string.external_file_keep))
+            }
+        },
+        dismissButton = {
+            TextButton(
+                onClick = { onConfirm(false, dontAsk) },
+                colors = ButtonDefaults.textButtonColors(contentColor = MaterialTheme.colorScheme.error)
+            ) {
+                Text(stringResource(R.string.external_file_delete))
+            }
+        }
+    )
+}
+
+@Composable
+fun ExternalFileBehaviorDialog(
+    currentBehavior: String,
+    onDismiss: () -> Unit,
+    onSelect: (String) -> Unit
+) {
+    AlertDialog(
+        onDismissRequest = onDismiss,
+        title = { Text(stringResource(R.string.options_external_file_behavior)) },
+        text = {
+            Column {
+                val options = listOf("ASK" to R.string.external_file_behavior_ask, "KEEP" to R.string.external_file_behavior_keep, "DELETE" to R.string.external_file_behavior_delete)
+                options.forEach { (value, labelRes) ->
+                    Row(
+                        verticalAlignment = Alignment.CenterVertically,
+                        modifier = Modifier
+                            .fillMaxWidth()
+                            .clickable { onSelect(value); onDismiss() }
+                            .padding(vertical = 12.dp)
+                    ) {
+                        RadioButton(selected = currentBehavior == value, onClick = null)
+                        Spacer(modifier = Modifier.width(16.dp))
+                        Text(stringResource(labelRes))
+                    }
+                }
+            }
+        },
+        confirmButton = {
+            TextButton(onClick = onDismiss) { Text(stringResource(R.string.action_cancel)) }
+        }
+    )
+}

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

@@ -1878,12 +1878,19 @@ fun LibraryFilterSheet(
                 }
             }
 
-            if (syncedFolders.isNotEmpty()) {
             Text(stringResource(R.string.filter_source_folder), style = MaterialTheme.typography.titleMedium)
             Row(
                 modifier = Modifier.fillMaxWidth().horizontalScroll(rememberScrollState()),
                 horizontalArrangement = Arrangement.spacedBy(8.dp)
             ) {
+                FilterChip(
+                    selected = "IN_APP_STORAGE" in currentFilters.sourceFolders,
+                    onClick = {
+                        val newSet = if ("IN_APP_STORAGE" in currentFilters.sourceFolders) currentFilters.sourceFolders - "IN_APP_STORAGE" else currentFilters.sourceFolders + "IN_APP_STORAGE"
+                        currentFilters = currentFilters.copy(sourceFolders = newSet)
+                              },
+                    label = { Text(stringResource(R.string.filter_in_app_storage)) }
+                )
                 syncedFolders.forEach { folder ->
                     FilterChip(
                         selected = folder.uriString in currentFilters.sourceFolders,
@@ -1895,7 +1902,6 @@ fun LibraryFilterSheet(
                     )
                 }
             }
-            }
 
             Text(stringResource(R.string.filter_read_status), style = MaterialTheme.typography.titleMedium)
             Row(

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

@@ -105,7 +105,7 @@ class MainActivity : ComponentActivity() {
         if (intent?.action == Intent.ACTION_VIEW && intent.data != null) {
             Timber.d("Received VIEW intent with URI: ${intent.data}")
             val uri = intent.data!!
-            viewModel.onFileSelected(uri)
+            viewModel.onFileSelected(uri, isFromRecent = false, isExternalIntent = true)
         }
     }
 }

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

@@ -240,6 +240,8 @@ data class ReaderScreenState(
     val openTabIds: List<String> = emptyList(),
     val openTabs: List<RecentFileItem> = emptyList(),
     val activeTabBookId: String? = null,
+    val showExternalFileSavePromptFor: String? = null,
+    val externalFileBehavior: String = "ASK",
 )
 
 open class MainViewModel(application: Application) : AndroidViewModel(application) {
@@ -279,6 +281,7 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
     @Suppress("unused")
     val navigationEvent = _navigationEvent.receiveAsFlow()
     private var pendingSwitchDeferred: CompletableDeferred<Boolean>? = null
+    private var externalOpenedBookId: String? = null
 
     data class PageModificationResult(
         val layout: List<VirtualPage>,
@@ -348,6 +351,7 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
                 } catch(_: Exception) { emptyList() }
             } ?: emptyList(),
             activeTabBookId = prefs.getString(KEY_ACTIVE_TAB, null),
+            externalFileBehavior = prefs.getString(KEY_EXTERNAL_FILE_BEHAVIOR, "ASK") ?: "ASK"
         )
     )
 
@@ -370,7 +374,11 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
         val filters = internalState.libraryFilters
         val libraryFiltered = baseVisibleFiles.filter { item ->
             val matchType = if (filters.fileTypes.isNotEmpty()) item.type in filters.fileTypes else true
-            val matchFolder = if (filters.sourceFolders.isNotEmpty()) item.sourceFolderUri in filters.sourceFolders 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
@@ -963,7 +971,6 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
 
             withContext(Dispatchers.Main) {
                 onDeleted()
-                showBanner(appContext.getString(R.string.banner_text_view_deleted))
             }
         }
     }
@@ -1487,6 +1494,7 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
             }
         }
 
+        val closingBookId = _internalState.value.selectedBookId
         val uriString = _internalState.value.selectedPdfUri?.toString()
             ?: _internalState.value.selectedEpubUri?.toString()
 
@@ -1504,6 +1512,16 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
             )
         }
 
+        if (closingBookId != null && closingBookId == externalOpenedBookId) {
+            val behavior = prefs.getString(KEY_EXTERNAL_FILE_BEHAVIOR, "ASK") ?: "ASK"
+            if (behavior == "ASK") {
+                _internalState.update { it.copy(showExternalFileSavePromptFor = closingBookId) }
+            } else if (behavior == "DELETE") {
+                deleteBookPermanently(closingBookId)
+            }
+            externalOpenedBookId = null
+        }
+
         if (uriString != null) {
             viewModelScope.launch {
                 val freshBook = recentFilesRepository.getFileByUri(uriString)
@@ -2819,7 +2837,7 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
         }
     }
 
-    fun onFileSelected(uri: Uri, isFromRecent: Boolean = false) {
+    fun onFileSelected(uri: Uri, isFromRecent: Boolean = false, isExternalIntent: Boolean = false) {
         if (isFromRecent) {
             Timber.i("Opening recent file: $uri")
             viewModelScope.launch {
@@ -2832,11 +2850,11 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
             }
         } else {
             Timber.i("Importing new file: $uri")
-            importExternalFile(uri)
+            importExternalFile(uri, isExternalIntent)
         }
     }
 
-    private fun importExternalFile(externalUri: Uri) {
+    private fun importExternalFile(externalUri: Uri, isExternalIntent: Boolean = false) {
         _internalState.update {
             it.copy(isLoading = true, errorMessage = null, contextualActionItems = emptySet())
         }
@@ -2846,6 +2864,9 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
 
             if (importResult != null) {
                 val (internalUri, bookId, type) = importResult
+                if (isExternalIntent) {
+                    externalOpenedBookId = bookId
+                }
                 val displayName = getFileNameFromUri(externalUri, appContext) ?: "Unknown File"
                 openBook(
                     internalUri, bookId = bookId, type = type, originalDisplayName = displayName
@@ -3734,12 +3755,25 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
     }
 
     fun selectAllRecentFiles() {
-        val recentFilesForHome = uiState.value.recentFiles.filter { it.isRecent }
+        val currentVisible = uiState.value.recentFiles.filter { it.isRecent }.toSet()
-        _internalState.update { it.copy(contextualActionItems = recentFilesForHome.toSet()) }
+        _internalState.update { state ->
+            if (state.contextualActionItems.containsAll(currentVisible) && currentVisible.isNotEmpty()) {
+                state.copy(contextualActionItems = emptySet())
+            } else {
+                state.copy(contextualActionItems = currentVisible)
+            }
+        }
     }
 
     fun selectAllLibraryFiles() {
-        _internalState.update { it.copy(contextualActionItems = uiState.value.recentFiles.toSet()) }
+        val currentVisible = uiState.value.allRecentFiles.toSet()
+        _internalState.update { state ->
+            if (state.contextualActionItems.containsAll(currentVisible) && currentVisible.isNotEmpty()) {
+                state.copy(contextualActionItems = emptySet())
+            } else {
+                state.copy(contextualActionItems = currentVisible)
+            }
+        }
     }
 
     fun clearContextualAction() {
@@ -3753,6 +3787,21 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
         _internalState.update { it.copy(showCreateShelfDialog = true) }
     }
 
+    fun handleExternalFilePrompt(bookId: String, keep: Boolean, dontAskAgain: Boolean) {
+        if (dontAskAgain) {
+            val newBehavior = if (keep) "KEEP" else "DELETE"
+            setExternalFileBehavior(newBehavior)
+        }
+        if (!keep) {
+            deleteBookPermanently(bookId)
+        }
+        _internalState.update { it.copy(showExternalFileSavePromptFor = null) }
+    }
+    fun setExternalFileBehavior(behavior: String) {
+        prefs.edit { putString(KEY_EXTERNAL_FILE_BEHAVIOR, behavior) }
+        _internalState.update { it.copy(externalFileBehavior = behavior) }
+    }
+
     fun dismissCreateShelfDialog() {
         _internalState.update { it.copy(showCreateShelfDialog = false) }
     }
@@ -4361,5 +4410,6 @@ open class MainViewModel(application: Application) : AndroidViewModel(applicatio
         private const val KEY_TABS_ENABLED = "tabs_enabled"
         private const val KEY_OPEN_TAB_IDS = "open_tab_ids"
         private const val KEY_ACTIVE_TAB = "active_tab_book_id"
+        private const val KEY_EXTERNAL_FILE_BEHAVIOR = "external_file_behavior"
     }
 }

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

@@ -577,6 +577,11 @@ fun ChapterWebView(
                                         )
                                     }
 
+                                    message.startsWith("NavDiag:") -> {
+                                        Timber.tag("NavDiag")
+                                            .d("JS -> ${message.substringAfter("NavDiag: ")}")
+                                    }
+
                                     message.startsWith("AutoScrollDiagnosis") -> {
                                         Timber.d(
                                             "JS -> ${message.substringAfter("AutoScrollDiagnosis: ")}"
@@ -726,13 +731,13 @@ fun ChapterWebView(
 
                             if (!initialCfi.isNullOrBlank()) {
                                 val cfiJsCommand = "javascript:window.scrollToCfi('$initialCfi');"
-                                Timber.tag("POS_DIAG").d("WebView onPageFinished: Triggering scroll to initialCfi: $initialCfi")
+                                Timber.tag("NavDiag").d("WebView onPageFinished: Triggering scroll to initialCfi: $initialCfi")
                                 view?.evaluateJavascript(cfiJsCommand) {
                                     onChapterInitiallyScrolled()
                                     scrollActionTaken = true
                                 }
                             } else if (!initialFragmentId.isNullOrBlank()) {
-                                Timber.d("WebView onPageFinished: Scrolling to Element ID: $initialFragmentId")
+                                Timber.tag("NavDiag").d("WebView onPageFinished: Scrolling to Element ID: $initialFragmentId")
                                 view?.evaluateJavascript(
                                     "javascript:var el = document.getElementById('$initialFragmentId'); if(el) { el.scrollIntoView(); } else { console.log('Element not found: $initialFragmentId'); }",
                                     null
@@ -744,9 +749,7 @@ fun ChapterWebView(
                                     ChapterScrollPosition.END -> "javascript:window.scrollToChapterEnd();"
                                     else -> "javascript:window.scrollToChapterStart();"
                                 }
-                                Timber.d(
+                                Timber.tag("NavDiag").d("WebView onPageFinished: Executing initial scroll to target: $initialScrollTarget")
-                                    "WebView onPageFinished: Executing initial scroll to target: $initialScrollTarget"
-                                )
                                 view?.evaluateJavascript(scrollJsCommand) {
                                     onChapterInitiallyScrolled()
                                     scrollActionTaken = true
@@ -754,17 +757,13 @@ fun ChapterWebView(
                             } else if (initialPageScrollY != null && initialPageScrollY > 0) {
                                 val scrollJsCommand =
                                     "javascript:window.scrollToSpecificY($initialPageScrollY);"
-                                Timber.d(
+                                Timber.tag("NavDiag").d("WebView onPageFinished: Executing initial scroll to Y: $initialPageScrollY")
-                                    "WebView onPageFinished: Executing initial scroll to Y: $initialPageScrollY"
-                                )
                                 view?.evaluateJavascript(scrollJsCommand) {
                                     onChapterInitiallyScrolled()
                                     scrollActionTaken = true
                                 }
                             } else {
-                                Timber.d(
+                                Timber.tag("NavDiag").d("WebView onPageFinished: No specific scroll, defaulting to start.")
-                                    "WebView onPageFinished: No specific scroll, defaulting to start."
-                                )
                                 view?.evaluateJavascript("javascript:window.scrollToChapterStart();") {
                                     onChapterInitiallyScrolled()
                                     scrollActionTaken = true

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

@@ -30,6 +30,11 @@ import androidx.annotation.RequiresApi
 import androidx.compose.animation.AnimatedContent
 import androidx.compose.animation.AnimatedVisibility
 import androidx.compose.animation.animateContentSize
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.items
+import androidx.compose.material.icons.filled.Settings
+import androidx.compose.material3.Switch
+import androidx.compose.material3.ModalBottomSheet
 import androidx.compose.animation.core.tween
 import androidx.compose.animation.fadeIn
 import androidx.compose.animation.fadeOut
@@ -69,6 +74,7 @@ import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.automirrored.filled.ArrowBack
 import androidx.compose.material.icons.filled.Add
 import androidx.compose.material.icons.filled.ArrowDropDown
+import androidx.compose.material.icons.filled.ArrowUpward
 import androidx.compose.material.icons.filled.Check
 import androidx.compose.material.icons.filled.ChevronLeft
 import androidx.compose.material.icons.filled.ChevronRight
@@ -131,6 +137,26 @@ import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
 import kotlin.math.roundToInt
 
+enum class ReaderTool(val title: String, val category: String) {
+    DICTIONARY("External Apps", "Top Bar"),
+    THEME("Theme Settings", "Top Bar"),
+    SLIDER("Navigation Slider", "Bottom Bar"),
+    TOC("Sidebar", "Bottom Bar"),
+    FORMAT("Text Formatting", "Bottom Bar"),
+    SEARCH("Search", "Bottom Bar"),
+    AI_FEATURES("AI Features", "Bottom Bar"),
+    TTS_CONTROLS("TTS Controls", "Bottom Bar"),
+    READING_MODE("Reading Mode", "Overflow Menu"),
+    BOOKMARK("Bookmark", "Overflow Menu"),
+    TAP_TO_TURN("Tap to Turn Pages", "Overflow Menu"),
+    VOLUME_SCROLL("Volume Button Scrolling", "Overflow Menu"),
+    PAGE_TURN_ANIM("Realistic Page Turns", "Overflow Menu"),
+    KEEP_SCREEN_ON("Keep Screen On", "Overflow Menu"),
+    VISUAL_OPTIONS("Visual Options", "Overflow Menu"),
+    AUTO_SCROLL("Auto Scroll", "Overflow Menu"),
+    TTS_SETTINGS("TTS Voice Settings", "Overflow Menu")
+}
+
 @Composable
 fun EpubReaderTopBar(
     isVisible: Boolean,
@@ -158,6 +184,8 @@ fun EpubReaderTopBar(
     onOpenThemeSettings: () -> Unit,
     onOpenVisualOptions: () -> Unit,
     searchFocusRequester: androidx.compose.ui.focus.FocusRequester,
+    hiddenTools: Set<String>,
+    onCustomizeTools: () -> Unit,
     modifier: Modifier = Modifier,
     onToggleReflow: (() -> Unit)? = null,
     onDeleteReflow: (() -> Unit)? = null,
@@ -204,6 +232,7 @@ fun EpubReaderTopBar(
                         overflow = TextOverflow.Ellipsis,
                         modifier = Modifier.weight(1f)
                     )
+                    if (!hiddenTools.contains(ReaderTool.DICTIONARY.name)) {
                         TooltipIconButton(
                             text = stringResource(R.string.tooltip_dictionary),
                             description = stringResource(R.string.tooltip_dictionary_desc),
@@ -214,6 +243,8 @@ fun EpubReaderTopBar(
                                 contentDescription = stringResource(R.string.content_desc_dictionary_settings)
                             )
                         }
+                    }
+                    if (!hiddenTools.contains(ReaderTool.THEME.name)) {
                         TooltipIconButton(
                             text = stringResource(R.string.tooltip_theme),
                             description = stringResource(R.string.tooltip_theme_desc),
@@ -221,6 +252,7 @@ fun EpubReaderTopBar(
                         ) {
                             Icon(painter = painterResource(id = R.drawable.palette), contentDescription = stringResource(R.string.tooltip_theme_desc))
                         }
+                    }
                     Box {
                         var showMoreMenu by remember { mutableStateOf(false) }
                         TooltipIconButton(
@@ -235,6 +267,18 @@ fun EpubReaderTopBar(
                             expanded = showMoreMenu,
                             onDismissRequest = { showMoreMenu = false }
                         ) {
+                            DropdownMenuItem(
+                                text = { Text("Customize Toolbar") },
+                                onClick = {
+                                    showMoreMenu = false
+                                    onCustomizeTools()
+                                },
+                                leadingIcon = {
+                                    Icon(Icons.Default.Settings, contentDescription = null, modifier = Modifier.size(20.dp))
+                                }
+                            )
+                            HorizontalDivider()
+
                             if (onToggleReflow != null) {
                                 DropdownMenuItem(
                                     text = { Text(stringResource(R.string.menu_view_original_pdf)) },
@@ -274,6 +318,7 @@ fun EpubReaderTopBar(
                                 )
                             }
 
+                            if (!hiddenTools.contains(ReaderTool.READING_MODE.name)) {
                                 DropdownMenuItem(
                                     text = { Text(stringResource(R.string.menu_reading_mode_vertical)) },
                                     enabled = !isTtsActive,
@@ -281,8 +326,12 @@ fun EpubReaderTopBar(
                                         showMoreMenu = false
                                         onChangeRenderMode(RenderMode.VERTICAL_SCROLL)
                                     },
-                                trailingIcon = { if (currentRenderMode == RenderMode.VERTICAL_SCROLL) Icon(Icons.Default.Check, contentDescription = stringResource(R.string.content_desc_selected)) }
+                                    trailingIcon = {
+                                        if (currentRenderMode == RenderMode.VERTICAL_SCROLL) Icon(
+                                            Icons.Default.Check,
+                                            contentDescription = stringResource(R.string.content_desc_selected)
                                         )
+                                    })
                                 DropdownMenuItem(
                                     text = { Text(stringResource(R.string.menu_reading_mode_paginated)) },
                                     enabled = !isTtsActive,
@@ -290,17 +339,28 @@ fun EpubReaderTopBar(
                                         showMoreMenu = false
                                         onChangeRenderMode(RenderMode.PAGINATED)
                                     },
-                                trailingIcon = { if (currentRenderMode == RenderMode.PAGINATED) Icon(Icons.Default.Check, contentDescription = stringResource(R.string.content_desc_selected)) }
+                                    trailingIcon = {
+                                        if (currentRenderMode == RenderMode.PAGINATED) Icon(
+                                            Icons.Default.Check,
+                                            contentDescription = stringResource(R.string.content_desc_selected)
                                         )
+                                    })
                                 HorizontalDivider()
-                            DropdownMenuItem(
+                            }
-                                text = { Text(if (isBookmarked) stringResource(R.string.menu_remove_bookmark) else stringResource(R.string.menu_bookmark_this_page)) },
+                            if (!hiddenTools.contains(ReaderTool.BOOKMARK.name)) {
-                                onClick = {
+                                DropdownMenuItem(text = {
+                                    Text(
+                                        if (isBookmarked) stringResource(R.string.menu_remove_bookmark) else stringResource(
+                                            R.string.menu_bookmark_this_page
+                                        )
+                                    )
+                                }, onClick = {
                                     showMoreMenu = false
                                     onToggleBookmark()
-                                }
+                                })
-                            )
                                 HorizontalDivider()
+                            }
+                            if (!hiddenTools.contains(ReaderTool.TAP_TO_TURN.name)) {
                                 DropdownMenuItem(
                                     text = { Text(stringResource(R.string.menu_tap_to_turn_pages)) },
                                     enabled = currentRenderMode == RenderMode.PAGINATED,
@@ -308,13 +368,21 @@ fun EpubReaderTopBar(
                                         onToggleTapToNavigate(!tapToNavigateEnabled)
                                         showMoreMenu = false
                                     },
-                                trailingIcon = { if (tapToNavigateEnabled) Icon(Icons.Default.Check, contentDescription = stringResource(R.string.content_desc_enabled)) }
+                                    trailingIcon = {
+                                        if (tapToNavigateEnabled) Icon(
+                                            Icons.Default.Check,
+                                            contentDescription = stringResource(R.string.content_desc_enabled)
                                         )
+                                    })
                                 HorizontalDivider()
+                            }
+                            if (!hiddenTools.contains(ReaderTool.VOLUME_SCROLL.name)) {
                                 DropdownMenuItem(
                                     text = {
                                     Text(
-                                        if (currentRenderMode == RenderMode.VERTICAL_SCROLL) stringResource(R.string.menu_volume_button_scrolling)
+                                        if (currentRenderMode == RenderMode.VERTICAL_SCROLL) stringResource(
+                                            R.string.menu_volume_button_scrolling
+                                        )
                                         else stringResource(R.string.menu_volume_button_page_turn)
                                     )
                                 },
@@ -323,10 +391,15 @@ fun EpubReaderTopBar(
                                         onToggleVolumeScroll(!volumeScrollEnabled)
                                         showMoreMenu = false
                                     },
-                                trailingIcon = { if (volumeScrollEnabled) Icon(Icons.Default.Check, contentDescription = stringResource(R.string.content_desc_enabled)) }
+                                    trailingIcon = {
+                                        if (volumeScrollEnabled) Icon(
+                                            Icons.Default.Check,
+                                            contentDescription = stringResource(R.string.content_desc_enabled)
                                         )
+                                    })
                                 HorizontalDivider()
-
+                            }
+                            if (!hiddenTools.contains(ReaderTool.PAGE_TURN_ANIM.name)) {
                                 DropdownMenuItem(
                                     text = { Text(stringResource(R.string.menu_realistic_page_turns)) },
                                     enabled = currentRenderMode == RenderMode.PAGINATED,
@@ -334,20 +407,30 @@ fun EpubReaderTopBar(
                                         onTogglePageTurnAnimation(!isPageTurnAnimationEnabled)
                                         showMoreMenu = false
                                     },
-                                trailingIcon = { if (isPageTurnAnimationEnabled) Icon(Icons.Default.Check, contentDescription = stringResource(R.string.content_desc_enabled)) }
+                                    trailingIcon = {
+                                        if (isPageTurnAnimationEnabled) Icon(
+                                            Icons.Default.Check,
+                                            contentDescription = stringResource(R.string.content_desc_enabled)
                                         )
+                                    })
                                 HorizontalDivider()
-
+                            }
+                            if (!hiddenTools.contains(ReaderTool.KEEP_SCREEN_ON.name)) {
                                 DropdownMenuItem(
                                     text = { Text(stringResource(R.string.menu_keep_screen_on)) },
                                     onClick = {
                                         onToggleKeepScreenOn(!isKeepScreenOn)
                                         showMoreMenu = false
                                     },
-                                trailingIcon = { if (isKeepScreenOn) Icon(Icons.Default.Check, contentDescription = stringResource(R.string.content_desc_enabled)) }
+                                    trailingIcon = {
+                                        if (isKeepScreenOn) Icon(
+                                            Icons.Default.Check,
+                                            contentDescription = stringResource(R.string.content_desc_enabled)
                                         )
+                                    })
                                 HorizontalDivider()
-
+                            }
+                            if (!hiddenTools.contains(ReaderTool.VISUAL_OPTIONS.name)) {
                                 DropdownMenuItem(
                                     text = { Text(stringResource(R.string.menu_visual_options)) },
                                     onClick = {
@@ -355,22 +438,25 @@ fun EpubReaderTopBar(
                                         onOpenVisualOptions()
                                     },
                                     leadingIcon = {
-                                    Icon(Icons.Default.Visibility, contentDescription = null, modifier = Modifier.size(20.dp))
+                                        Icon(
-                                }
+                                            Icons.Default.Visibility,
+                                            contentDescription = null,
+                                            modifier = Modifier.size(20.dp)
                                         )
+                                    })
                                 HorizontalDivider()
-
+                            }
+                            if (!hiddenTools.contains(ReaderTool.AUTO_SCROLL.name)) {
                                 DropdownMenuItem(
                                     text = { Text(stringResource(R.string.menu_auto_scroll)) },
                                     enabled = !isTtsActive && currentRenderMode == RenderMode.VERTICAL_SCROLL,
                                     onClick = {
                                         showMoreMenu = false
                                         onStartAutoScroll()
-                                }
+                                    })
-                            )
-
                                 HorizontalDivider()
-
+                            }
+                            if (!hiddenTools.contains(ReaderTool.TTS_SETTINGS.name)) {
                                 DropdownMenuItem(
                                     text = { Text(stringResource(R.string.menu_tts_voice_settings)) },
                                     onClick = {
@@ -378,9 +464,12 @@ fun EpubReaderTopBar(
                                         onOpenDeviceVoiceSettings()
                                     },
                                     leadingIcon = {
-                                    Icon(Icons.Default.GraphicEq, contentDescription = null, modifier = Modifier.size(20.dp))
+                                        Icon(
-                                }
+                                            Icons.Default.GraphicEq,
+                                            contentDescription = null,
+                                            modifier = Modifier.size(20.dp)
                                         )
+                                    })
 
                                 if (BuildConfig.DEBUG) {
                                     DropdownMenuItem(
@@ -390,7 +479,11 @@ fun EpubReaderTopBar(
                                             onOpenTtsSettings()
                                         },
                                         leadingIcon = {
-                                        Icon(painter = painterResource(id = R.drawable.text_to_speech), contentDescription = null, modifier = Modifier.size(20.dp))
+                                            Icon(
+                                                painter = painterResource(id = R.drawable.text_to_speech),
+                                                contentDescription = null,
+                                                modifier = Modifier.size(20.dp)
+                                            )
                                         }
                                     )
                                 }
@@ -400,6 +493,7 @@ fun EpubReaderTopBar(
                 }
             }
         }
+    }
 }
 
 @androidx.annotation.OptIn(UnstableApi::class)
@@ -418,6 +512,7 @@ fun EpubReaderBottomBar(
     onRecap: () -> Unit,
     onToggleTts: () -> Unit,
     onPlayPauseTts: () -> Unit,
+    hiddenTools: Set<String>,
     modifier: Modifier = Modifier
 ) {
     AnimatedVisibility(
@@ -439,58 +534,81 @@ fun EpubReaderBottomBar(
                 verticalAlignment = Alignment.CenterVertically,
                 horizontalArrangement = Arrangement.SpaceAround
             ) {
+                if (!hiddenTools.contains(ReaderTool.SLIDER.name)) {
                     TooltipIconButton(
                         text = stringResource(R.string.tooltip_slider),
                         description = stringResource(R.string.tooltip_slider_desc),
                         onClick = onOpenSlider,
                         enabled = currentRenderMode != RenderMode.VERTICAL_SCROLL
                     ) {
-                    Icon(painter = painterResource(id = R.drawable.slider), contentDescription = stringResource(R.string.content_desc_navigate_slider))
+                        Icon(
+                            painter = painterResource(id = R.drawable.slider),
+                            contentDescription = stringResource(R.string.content_desc_navigate_slider)
+                        )
                     }
+                }
+                if (!hiddenTools.contains(ReaderTool.TOC.name)) {
                     TooltipIconButton(
                         text = stringResource(R.string.tooltip_toc),
                         description = stringResource(R.string.tooltip_toc_desc),
                         onClick = onOpenDrawer
                     ) {
-                    Icon(imageVector = Icons.Default.Menu, contentDescription = stringResource(R.string.content_desc_chapters_menu))
+                        Icon(
+                            imageVector = Icons.Default.Menu,
+                            contentDescription = stringResource(R.string.content_desc_chapters_menu)
+                        )
                     }
+                }
+                if (!hiddenTools.contains(ReaderTool.FORMAT.name)) {
                     TooltipIconButton(
                         text = stringResource(R.string.tooltip_format),
                         description = stringResource(R.string.tooltip_format_desc),
                         onClick = onToggleFormat
                     ) {
-                    Icon(painter = painterResource(id = R.drawable.format_size), contentDescription = stringResource(R.string.content_desc_text_formatting))
+                        Icon(
+                            painter = painterResource(id = R.drawable.format_size),
+                            contentDescription = stringResource(R.string.content_desc_text_formatting)
+                        )
                     }
+                }
+                if (!hiddenTools.contains(ReaderTool.SEARCH.name)) {
                     TooltipIconButton(
                         text = stringResource(R.string.tooltip_search),
                         description = stringResource(R.string.tooltip_search_desc),
                         onClick = onToggleSearch
                     ) {
-                    Icon(imageVector = Icons.Default.Search, contentDescription = stringResource(R.string.tooltip_search))
+                        Icon(
+                            imageVector = Icons.Default.Search,
+                            contentDescription = stringResource(R.string.tooltip_search)
+                        )
+                    }
                 }
 
-                @Suppress("KotlinConstantConditions", "SimplifyBooleanWithConstants")
+                if (!hiddenTools.contains(ReaderTool.AI_FEATURES.name)) {
-                if (BuildConfig.FLAVOR != "oss") {
+                    @Suppress(
+                        "KotlinConstantConditions",
+                        "SimplifyBooleanWithConstants"
+                    ) if (BuildConfig.FLAVOR != "oss") {
                         Box {
                             var showAiFeaturesMenu by remember { mutableStateOf(false) }
                             TooltipIconButton(
                                 text = stringResource(R.string.tooltip_ai),
                                 description = stringResource(R.string.tooltip_ai_desc),
-                            onClick = { showAiFeaturesMenu = true }
+                                onClick = { showAiFeaturesMenu = true }) {
-                        ) {
+                                Icon(
-                            Icon(painter = painterResource(id = R.drawable.ai), contentDescription = "AI Features")
+                                    painter = painterResource(id = R.drawable.ai),
+                                    contentDescription = "AI Features"
+                                )
                             }
                             DropdownMenu(
                                 expanded = showAiFeaturesMenu,
-                            onDismissRequest = { showAiFeaturesMenu = false }
+                                onDismissRequest = { showAiFeaturesMenu = false }) {
-                        ) {
                                 DropdownMenuItem(
                                     text = { Text(stringResource(R.string.menu_chapter_summarization)) },
                                     onClick = {
                                         showAiFeaturesMenu = false
                                         onSummarize()
-                                }
+                                    })
-                            )
                                 if (BuildConfig.DEBUG && isProUser) {
                                     HorizontalDivider()
                                     DropdownMenuItem(
@@ -498,46 +616,46 @@ fun EpubReaderBottomBar(
                                         onClick = {
                                             showAiFeaturesMenu = false
                                             onRecap()
-                                    }
+                                        })
-                                )
                                 }
                             }
                         }
                     }
+                }
+
+                if (!hiddenTools.contains(ReaderTool.TTS_CONTROLS.name)) {
                     Box {
                         Row(verticalAlignment = Alignment.CenterVertically) {
                             TooltipIconButton(
-                            text = if (isTtsSessionActive)
+                                text = if (isTtsSessionActive) stringResource(R.string.tooltip_tts_stop)
-                                stringResource(R.string.tooltip_tts_stop)
+                                else stringResource(R.string.tooltip_tts_start),
-                            else
+                                description = if (isTtsSessionActive) stringResource(R.string.tooltip_tts_stop_desc)
-                                stringResource(R.string.tooltip_tts_start),
+                                else stringResource(R.string.tooltip_tts_start_desc),
-                            description = if (isTtsSessionActive)
-                                stringResource(R.string.tooltip_tts_stop_desc)
-                            else
-                                stringResource(R.string.tooltip_tts_start_desc),
                                 onClick = onToggleTts
                             ) {
                                 Icon(
-                                painter = if (isTtsSessionActive) painterResource(id = R.drawable.close) else painterResource(id = R.drawable.text_to_speech),
+                                    painter = if (isTtsSessionActive) painterResource(id = R.drawable.close) else painterResource(
-                                contentDescription = if (isTtsSessionActive) stringResource(R.string.content_desc_stop_tts) else stringResource(R.string.content_desc_start_tts)
+                                        id = R.drawable.text_to_speech
+                                    ),
+                                    contentDescription = if (isTtsSessionActive) stringResource(R.string.content_desc_stop_tts) else stringResource(
+                                        R.string.content_desc_start_tts
+                                    )
                                 )
                             }
                             if (isTtsSessionActive) {
                                 TooltipIconButton(
-                                text = if (ttsState.isPlaying)
+                                    text = if (ttsState.isPlaying) stringResource(R.string.tooltip_tts_pause)
-                                    stringResource(R.string.tooltip_tts_pause)
+                                    else stringResource(R.string.tooltip_tts_resume),
-                                else
+                                    description = if (ttsState.isPlaying) stringResource(R.string.tooltip_tts_pause_desc)
-                                    stringResource(R.string.tooltip_tts_resume),
+                                    else stringResource(R.string.tooltip_tts_resume_desc),
-                                description = if (ttsState.isPlaying)
-                                    stringResource(R.string.tooltip_tts_pause_desc)
-                                else
-                                    stringResource(R.string.tooltip_tts_resume_desc),
                                     onClick = onPlayPauseTts,
                                     enabled = !ttsState.isLoading
                                 ) {
                                     Icon(
                                         painter = painterResource(id = if (ttsState.isPlaying) R.drawable.pause else R.drawable.play),
-                                    contentDescription = if (ttsState.isPlaying) stringResource(R.string.content_desc_pause_tts) else stringResource(R.string.content_desc_resume_tts)
+                                        contentDescription = if (ttsState.isPlaying) stringResource(
+                                            R.string.content_desc_pause_tts
+                                        ) else stringResource(R.string.content_desc_resume_tts)
                                     )
                                 }
                             }
@@ -546,6 +664,7 @@ fun EpubReaderBottomBar(
                 }
             }
         }
+    }
 }
 
 @RequiresApi(Build.VERSION_CODES.VANILLA_ICE_CREAM)
@@ -885,6 +1004,7 @@ fun AutoScrollControls(
     onLocalModeToggle: (Boolean) -> Unit,
     modifier: Modifier = Modifier,
     isTempPaused: Boolean = false,
+    onScrollToTop: (() -> Unit)? = null
 ) {
     val backgroundAlpha = 0.6f
 
@@ -1018,6 +1138,19 @@ fun AutoScrollControls(
                         }
 
                         Row(horizontalArrangement = Arrangement.spacedBy(4.dp)) {
+                            if (onScrollToTop != null) {
+                                IconButton(
+                                    onClick = onScrollToTop,
+                                    modifier = Modifier.size(32.dp)
+                                ) {
+                                    Icon(
+                                        imageVector = Icons.Default.ArrowUpward,
+                                        contentDescription = "Scroll to Top",
+                                        modifier = Modifier.size(18.dp),
+                                        tint = MaterialTheme.colorScheme.onSurfaceVariant
+                                    )
+                                }
+                            }
                             IconButton(
                                 onClick = onMusicianModeToggle,
                                 modifier = Modifier.size(32.dp)
@@ -1217,3 +1350,75 @@ fun AutoScrollControls(
         }
     }
 }
+
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+fun CustomizeToolsSheet(
+    hiddenTools: Set<String>,
+    onUpdate: (Set<String>) -> Unit,
+    onDismiss: () -> Unit
+) {
+    ModalBottomSheet(
+        onDismissRequest = onDismiss,
+        contentWindowInsets = { WindowInsets.navigationBars }
+    ) {
+        Column(modifier = Modifier.padding(horizontal = 24.dp).padding(bottom = 24.dp)) {
+            Text(
+                text = "Customize Toolbar",
+                style = MaterialTheme.typography.headlineSmall,
+                fontWeight = FontWeight.Bold,
+                color = MaterialTheme.colorScheme.onSurface
+            )
+            Spacer(modifier = Modifier.height(8.dp))
+            Text(
+                text = "Select the tools you want to keep visible. Unchecking a tool hides it from the UI to give you a distraction-free reading space.",
+                style = MaterialTheme.typography.bodyMedium,
+                color = MaterialTheme.colorScheme.onSurfaceVariant
+            )
+            Spacer(modifier = Modifier.height(16.dp))
+
+            LazyColumn(modifier = Modifier.fillMaxWidth()) {
+                ReaderTool.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)
+                        )
+                    }
+                    items(tools) { tool ->
+                        Row(
+                            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)
+                                }
+                                .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)
+                                }
+                            )
+                        }
+                    }
+                }
+            }
+        }
+    }
+}

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

@@ -214,6 +214,17 @@ private const val AUTO_SCROLL_LOCAL_MIN_PREFIX = "auto_scroll_local_min_"
 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 fun saveHiddenTools(context: Context, hiddenTools: Set<String>) {
+    val prefs = context.getSharedPreferences("reader_prefs", Context.MODE_PRIVATE)
+    prefs.edit { putStringSet(HIDDEN_TOOLS_KEY, hiddenTools) }
+}
+
+private fun loadHiddenTools(context: Context): Set<String> {
+    val prefs = context.getSharedPreferences("reader_prefs", Context.MODE_PRIVATE)
+    return prefs.getStringSet(HIDDEN_TOOLS_KEY, emptySet()) ?: emptySet()
+}
 
 private fun saveKeepScreenOn(context: Context, isEnabled: Boolean) {
     val prefs = context.getSharedPreferences("reader_prefs", Context.MODE_PRIVATE)
@@ -655,6 +666,9 @@ fun EpubReaderHost(
         mutableStateOf(loadExternalSearchPackage(context))
     }
 
+    var hiddenTools by remember { mutableStateOf(loadHiddenTools(context)) }
+    var showCustomizeToolsSheet by remember { mutableStateOf(false) }
+
     var showDictionaryUpsellDialog by remember { mutableStateOf(false) }
     var showSummarizationUpsellDialog by remember { mutableStateOf(false) }
 
@@ -1603,6 +1617,7 @@ fun EpubReaderHost(
     }
 
     fun navigateToSearchResult(index: Int) {
+        Timber.tag("NavDiag").d("navigateToSearchResult index: $index")
         performSearchResultNavigation(
             index = index,
             searchState = searchState,
@@ -1613,17 +1628,36 @@ fun EpubReaderHost(
             paginator = paginator,
             coroutineScope = scope,
             onVerticalChapterChange = { chapterIdx, chunkIdx, result ->
-                initialScrollTargetForChapter = ChapterScrollPosition.START
+                Timber.tag("NavDiag").d("onVerticalChapterChange chapterIdx=$chapterIdx, chunkIdx=$chunkIdx, query=${result.query}")
+                initialScrollTargetForChapter = null
+                chunkTargetOverride = chunkIdx
                 currentScrollYPosition = 0
                 currentScrollHeightValue = 0
                 currentChapterIndex = chapterIdx
                 searchHighlightTarget = result
-                loadUpToChunkIndex = chunkIdx
             },
-            onVerticalScrollToResult = { _ ->
+            onVerticalScrollToResult = { result ->
-                searchHighlightTarget = null
+                Timber.tag("NavDiag").d("onVerticalScrollToResult query=${result.query}, chunk=${result.chunkIndex}")
+                val targetChunk = result.chunkIndex
+                if (targetChunk >= loadedChunkCount) {
+                    val chunksToInject = (loadedChunkCount..targetChunk)
+                    chunksToInject.forEach { idx ->
+                        val content = chapterChunks.getOrNull(idx)
+                        if (content != null) {
+                            val escaped = escapeJsString(content)
+                            webViewRefForTts?.evaluateJavascript(
+                                "javascript:window.virtualization.appendChunk($idx, '$escaped');",
+                                null
+                            )
+                        }
+                    }
+                    loadUpToChunkIndex = targetChunk
+                    loadedChunkCount = max(loadedChunkCount, targetChunk + 1)
+                }
+                searchHighlightTarget = result
             },
             onPaginatedScrollToPage = { pageIdx ->
+                Timber.tag("NavDiag").d("onPaginatedScrollToPage pageIdx=$pageIdx")
                 paginatedPagerState.scrollToPage(pageIdx)
             }
         )
@@ -1763,23 +1797,8 @@ fun EpubReaderHost(
                                 Timber.tag("BookmarkDiagnosis").d("Navigating to ${bookmark.cfi}")
                                 cfiToLoad = bookmark.cfi
 
-                                val directChunkIndex = try {
+                                val locator = locatorConverter.getLocatorFromCfi(epubBook, bookmark.chapterIndex, bookmark.cfi)
-                                    val parts = bookmark.cfi.split('/').mapNotNull { it.toIntOrNull() }
+                                val targetChunk = locator?.let { it.blockIndex / 20 }
-                                    if (parts.isNotEmpty()) {
-                                        val firstIndex = parts[0]
-                                        (firstIndex - 2) / 2
-                                    } else null
-                                } catch (_: Exception) {
-                                    null
-                                }
-
-                                val locator = if (directChunkIndex == null) {
-                                    locatorConverter.getLocatorFromCfi(epubBook, bookmark.chapterIndex, bookmark.cfi)
-                                } else {
-                                    null
-                                }
-
-                                val targetChunk = directChunkIndex ?: locator?.let { it.blockIndex / 20 }
 
                                 if (bookmark.chapterIndex != currentChapterIndex) {
                                     chunkTargetOverride = if (targetChunk != null && targetChunk >= 0) {
@@ -2168,7 +2187,7 @@ fun EpubReaderHost(
                                     } else if (chapterChunks.isNotEmpty()) {
                                         val initialContentToLoad = remember(loadUpToChunkIndex, chapterChunks) {
                                             val targetIdx = loadUpToChunkIndex
-                                            val startIdx = maxOf(0, targetIdx - 1)
+                                            val startIdx = 0
                                             val endIdx = minOf(chapterChunks.lastIndex, targetIdx + 1)
 
                                             chapterChunks.indices.joinToString(separator = "\n") { index ->
@@ -2221,30 +2240,31 @@ fun EpubReaderHost(
                                             )
                                         }
 
-                                        LaunchedEffect(isWebViewReady) {
+                                        LaunchedEffect(isWebViewReady, searchHighlightTarget) {
                                             val target = searchHighlightTarget
-                                            Timber.d("Effect(isWebViewReady=$isWebViewReady) triggered for chapter $targetChapterIndex. Target is: $target"
+                                            Timber.tag("NavDiag").d("Effect(isWebViewReady=$isWebViewReady, target=$target) triggered for chapter $targetChapterIndex.")
-                                            )
 
                                             if (isWebViewReady && target != null && target.locationInSource == targetChapterIndex) {
-                                                Timber.d("Highlighting condition met. Highlighting now."
+                                                Timber.tag("NavDiag").d("Highlighting condition met. Highlighting now.")
-                                                )
                                                 delay(200)
                                                 val webView = webViewRefForTts
                                                 if (webView != null) {
                                                     val escapedQuery = escapeJsString(target.query)
-                                                    val js =
+                                                    val targetChunk = target.chunkIndex
-                                                        "javascript:window.highlightAllOccurrences('${escapedQuery}'); window.scrollToOccurrence(${target.occurrenceIndexInLocation});"
+
-                                                    Timber.d("Executing search highlight/scroll JS: $js"
+                                                    val relativeIdx = searchState.searchResults
-                                                    )
+                                                        .filter { it.locationInSource == target.locationInSource && it.chunkIndex == targetChunk }
+                                                        .indexOf(target)
+                                                        .coerceAtLeast(0)
+
+                                                    val js = "javascript:console.log('NavDiag: Executing robust search highlight JS'); window.CURRENT_SEARCH_QUERY = '${escapedQuery}'; window.highlightAllOccurrences('${escapedQuery}'); window.scrollToChunkOccurrence($targetChunk, $relativeIdx);"
+                                                    Timber.tag("NavDiag").d("Executing search highlight/scroll JS: $js")
                                                     webView.evaluateJavascript(js) { result ->
-                                                        Timber.d("JS highlight/scroll result: $result"
+                                                        Timber.tag("NavDiag").d("JS highlight/scroll result: $result")
-                                                        )
                                                     }
                                                     searchHighlightTarget = null
                                                 } else {
-                                                    Timber.w("Highlight failed: WebView was null even after ready signal."
+                                                    Timber.tag("NavDiag").w("Highlight failed: WebView was null even after ready signal.")
-                                                    )
                                                     searchHighlightTarget = null
                                                 }
                                             }
@@ -2305,6 +2325,7 @@ fun EpubReaderHost(
                                             },
                                             onChapterInitiallyScrolled = {
                                                 val wasCfiScroll = cfiToLoad != null
+                                                Timber.tag("NavDiag").d("onChapterInitiallyScrolled for chapter $targetChapterIndex. Was CFI scroll: $wasCfiScroll")
                                                 initialScrollTargetForChapter = null
                                                 cfiToLoad = null
                                                 fragmentToLoad = null
@@ -3485,6 +3506,8 @@ fun EpubReaderHost(
                     tapToNavigateEnabled = tapToNavigateEnabled,
                     volumeScrollEnabled = volumeScrollEnabled,
                     isPageTurnAnimationEnabled = isPageTurnAnimationEnabled,
+                    hiddenTools = hiddenTools,
+                    onCustomizeTools = { showCustomizeToolsSheet = true },
                     onNavigateBack = { triggerSaveAndExit() },
                     isKeepScreenOn = isKeepScreenOn,
                     onToggleKeepScreenOn = { enabled ->
@@ -3497,23 +3520,34 @@ fun EpubReaderHost(
                         keyboardController?.hide()
                         focusManager.clearFocus()
                         containerFocusRequester.requestFocus()
+                        webViewRefForTts?.evaluateJavascript("javascript:window.clearSearchHighlights();", null)
                     },
                     onChangeRenderMode = { newMode ->
+                        Timber.tag("NavDiag").d("onChangeRenderMode to $newMode")
                         if (newMode != currentRenderMode) {
                             if (newMode == RenderMode.PAGINATED) {
                                 isSwitchingToPaginated = true
                                 webViewRefForTts?.evaluateJavascript("javascript:CfiBridge.onCfiExtracted(window.getCurrentCfi());", null)
                             } else {
                                 scope.launch {
+                                    Timber.tag("NavDiag").d("Mode changing to VERTICAL. lastKnownLocator=$lastKnownLocator")
                                     lastKnownLocator?.let { locator ->
                                         val cfi = locatorConverter.getCfiFromLocator(epubBook, locator)
+                                        Timber.tag("NavDiag").d("Converted locator to CFI: $cfi")
                                         if (cfi != null) {
                                             val targetChunk = locator.blockIndex / 20
                                             chunkTargetOverride = targetChunk
                                             if (currentChapterIndex != locator.chapterIndex) {
+                                                initialScrollTargetForChapter = null
                                                 currentScrollYPosition = 0
                                                 currentScrollHeightValue = 0
                                                 currentChapterIndex = locator.chapterIndex
+                                            } else {
+                                                if (targetChunk > loadUpToChunkIndex) {
+                                                    loadUpToChunkIndex = targetChunk
+                                                    loadedChunkCount = max(loadedChunkCount, targetChunk + 1)
+                                                }
+                                                initialScrollTargetForChapter = null
                                             }
                                             cfiToLoad = cfi
                                         } else {
@@ -3661,7 +3695,15 @@ fun EpubReaderHost(
                             saveAutoScrollUseSlider(context, autoScrollUseSlider)
                         },
                         isLocalMode = isAutoScrollLocal,
-                        onLocalModeToggle = onToggleAutoScrollMode
+                        onLocalModeToggle = onToggleAutoScrollMode,
+                        onScrollToTop = {
+                            if (isAutoScrollPlaying) {
+                                triggerAutoScrollTempPause(1000L)
+                            }
+                            scope.launch {
+                                webViewRefForTts?.evaluateJavascript("window.scrollTo({ top: 0, behavior: 'smooth' });", null)
+                            }
+                        }
                     )
                 }
 
@@ -3672,6 +3714,7 @@ fun EpubReaderHost(
                     isTtsSessionActive = isTtsSessionActive,
                     ttsState = ttsState,
                     isProUser = isProUser,
+                    hiddenTools = hiddenTools,
                     onOpenSlider = {
                         when (currentRenderMode) {
                             RenderMode.VERTICAL_SCROLL -> {
@@ -4123,6 +4166,17 @@ fun EpubReaderHost(
             )
         }
 
+        if (showCustomizeToolsSheet) {
+            CustomizeToolsSheet(
+                hiddenTools = hiddenTools,
+                onUpdate = { newHiddenSet ->
+                    hiddenTools = newHiddenSet
+                    saveHiddenTools(context, newHiddenSet)
+                },
+                onDismiss = { showCustomizeToolsSheet = false }
+            )
+        }
+
         if (showDictionarySettingsSheet) {
             DictionarySettingsDialog(
                 isVisible = true,

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

@@ -294,7 +294,7 @@ class OpdsParser {
     private fun parseOpds2Navigation(nav: JSONObject, baseUrl: String): OpdsEntry {
         val title = nav.optString("title", "Unknown")
         val href = nav.optString("href")
-        val summary = nav.optString("description", null)
+        val summary = nav.optString("description")
         val navigationUrl = if (href.isNotEmpty()) resolveUrl(baseUrl, href) else null
 
         return OpdsEntry(

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

@@ -21,7 +21,15 @@ class OpdsRepository(context: Context) {
         private const val KEY_CATALOGS_JSON = "opds_catalogs_json"
 
         val sharedHttpClient: OkHttpClient by lazy {
-            OkHttpClient.Builder().build()
+            OkHttpClient.Builder()
+                .addInterceptor { chain ->
+                    val originalRequest = chain.request()
+                    val requestWithUserAgent = originalRequest.newBuilder()
+                        .header("User-Agent", "EpistemeReader/1.0 (Android)")
+                        .build()
+                    chain.proceed(requestWithUserAgent)
+                }
+                .build()
         }
     }
 
@@ -54,6 +62,8 @@ class OpdsRepository(context: Context) {
 
         if (catalogs.isEmpty()) {
             catalogs.add(OpdsCatalog(UUID.randomUUID().toString(), "Project Gutenberg", "https://m.gutenberg.org/ebooks.opds/", isDefault = true))
+            catalogs.add(OpdsCatalog(UUID.randomUUID().toString(), "Standard Ebooks", "https://standardebooks.org/feeds/opds", isDefault = true))
+
             saveCatalogs(catalogs)
         }
 

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

@@ -123,7 +123,7 @@ import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.NonCancellable
 import kotlinx.coroutines.channels.Channel
 import kotlinx.coroutines.coroutineScope
-import kotlinx.coroutines.flow.collectLatest
+import kotlinx.coroutines.flow.conflate
 import kotlinx.coroutines.isActive
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
@@ -1104,12 +1104,12 @@ internal fun PdfPageComposable(
         try {
             page = withContext(Dispatchers.IO) { pdfDocumentItem.openPage(pdfPageIndex) }
 
-            snapshotFlow { visibleScreenRect() }.collectLatest { currentVisibleRect ->
+            snapshotFlow { visibleScreenRect() }.conflate().collect { currentVisibleRect ->
                 val tileCalcStart = System.nanoTime()
-                if (!isActive) return@collectLatest
+                if (!isActive) return@collect
 
                 if (isScrolling && effectiveScale > 1f) {
-                    return@collectLatest
+                    return@collect
                 }
 
                 val pxTl: Float
@@ -1131,7 +1131,7 @@ internal fun PdfPageComposable(
                                 oldTiles.forEach { PdfBitmapPool.recycle(it.bitmap) }
                             }
                         }
-                        return@collectLatest
+                        return@collect
                     }
                 } else {
                     val pivotX = screenWidth / 2f

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

@@ -139,6 +139,8 @@ class VerticalPdfReaderState {
     internal var scrollToPageHandler: (suspend (Int) -> Unit)? = null
     internal var snapToPageHandler: (suspend (Int) -> Unit)? = null
     internal var scrollByHandler: (suspend (Float) -> Unit)? = null
+    internal var scrollToTopHandler: (suspend () -> Unit)? = null
+    internal var scrollToBottomHandler: (suspend () -> Unit)? = null
 
     suspend fun scrollToPage(pageIndex: Int) {
         scrollToPageHandler?.invoke(pageIndex)
@@ -151,6 +153,14 @@ class VerticalPdfReaderState {
     suspend fun scrollBy(delta: Float) {
         scrollByHandler?.invoke(delta)
     }
+
+    suspend fun scrollToTop() {
+        scrollToTopHandler?.invoke()
+    }
+
+    suspend fun scrollToBottom() {
+        scrollToBottomHandler?.invoke()
+    }
 }
 
 @Composable
@@ -244,6 +254,8 @@ internal fun PdfVerticalReader(
             state.scrollToPageHandler = null
             state.snapToPageHandler = null
             state.scrollByHandler = null
+            state.scrollToTopHandler = null
+            state.scrollToBottomHandler = null
         }
     }
     var globalEraserPosition by remember { mutableStateOf<Offset?>(null) }
@@ -527,6 +539,23 @@ internal fun PdfVerticalReader(
                     )
                 }
             }
+
+            state.scrollToTopHandler = {
+                panYAnimatable.animateTo(
+                    targetValue = headerHeightPx,
+                    animationSpec = tween(durationMillis = 500, easing = FastOutSlowInEasing)
+                )
+            }
+
+            state.scrollToBottomHandler = {
+                val currentZoom = zoomAnimatable.value
+                val zoomedDocHeight = totalDocHeight * currentZoom
+                val minPanY = (screenHeight - footerHeightPx - zoomedDocHeight).coerceAtMost(headerHeightPx)
+                panYAnimatable.animateTo(
+                    targetValue = minPanY,
+                    animationSpec = tween(durationMillis = 500, easing = FastOutSlowInEasing)
+                )
+            }
         }
 
         var selectionClearTrigger by remember { mutableLongStateOf(0L) }

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

@@ -20,7 +20,7 @@
 // PdfViewerScreen.kt
 @file:Suppress("COMPOSE_APPLIER_CALL_MISMATCH", "Unused", "UnusedVariable",
     "SimplifyBooleanWithConstants"
-)
+) @file:kotlin.OptIn(ExperimentalMaterial3Api::class)
 
 package com.aryan.reader.pdf
 
@@ -30,6 +30,8 @@ import android.app.Activity
 import android.content.ClipData
 import android.content.Context
 import android.content.pm.PackageManager
+import androidx.compose.material3.Switch
+import androidx.compose.material.icons.filled.Settings
 import android.graphics.Bitmap
 import android.graphics.RectF
 import android.net.Uri
@@ -91,6 +93,7 @@ import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.heightIn
 import androidx.compose.foundation.layout.ime
+import androidx.compose.foundation.layout.navigationBars
 import androidx.compose.foundation.layout.offset
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
@@ -364,6 +367,42 @@ private const val PREF_EXTERNAL_TRANSLATE_PKG = "external_translate_package"
 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 fun loadPdfHiddenTools(context: Context): Set<String> {
+    val prefs = context.getSharedPreferences(SETTINGS_PREFS_NAME, Context.MODE_PRIVATE)
+    return prefs.getStringSet(PDF_HIDDEN_TOOLS_KEY, emptySet()) ?: emptySet()
+}
+
+private fun savePdfHiddenTools(context: Context, hiddenTools: Set<String>) {
+    val prefs = context.getSharedPreferences(SETTINGS_PREFS_NAME, Context.MODE_PRIVATE)
+    prefs.edit { putStringSet(PDF_HIDDEN_TOOLS_KEY, hiddenTools) }
+}
+
+enum class PdfReaderTool(val title: String, val category: String) {
+    DICTIONARY("External Apps", "Top Bar"),
+    THEME("Theme Settings", "Top Bar"),
+    LOCK_PANNING("Lock Panning", "Top Bar"),
+    FULL_SCREEN("Full Screen", "Top Bar"),
+    SLIDER("Navigation Slider", "Bottom Bar"),
+    TOC("Sidebar", "Bottom Bar"),
+    SEARCH("Search", "Bottom Bar"),
+    HIGHLIGHT_ALL("Highlight selectable text", "Bottom Bar"),
+    AI_FEATURES("AI Features", "Bottom Bar"),
+    EDIT_MODE("Edit Mode", "Bottom Bar"),
+    TTS_CONTROLS("TTS Controls", "Bottom Bar"),
+    OCR_LANGUAGE("OCR Language", "Overflow Menu"),
+    READING_MODE("Reading Mode", "Overflow Menu"),
+    KEEP_SCREEN_ON("Keep Screen On", "Overflow Menu"),
+    AUTO_SCROLL("Auto Scroll", "Overflow Menu"),
+    TTS_SETTINGS("TTS Voice Settings", "Overflow Menu"),
+    BOOKMARK("Bookmark", "Overflow Menu"),
+    PAGE_MANAGEMENT("Page Management", "Overflow Menu"),
+    REFLOW("Text View (Reflow)", "Overflow Menu"),
+    SHARE("Share", "Overflow Menu"),
+    SAVE_COPY("Save Copy", "Overflow Menu"),
+    PRINT("Print", "Overflow Menu")
+}
 
 private fun loadCustomHighlightColors(context: Context): Map<PdfHighlightColor, Color> {
     val prefs = context.getSharedPreferences(SETTINGS_PREFS_NAME, Context.MODE_PRIVATE)
@@ -1213,6 +1252,14 @@ fun PdfViewerScreen(
     var showReindexDialog by remember { mutableStateOf<OcrLanguage?>(null) }
     var pendingActionAfterOcrSelection by remember { mutableStateOf<(() -> Unit)?>(null) }
 
+    var showCustomizeToolsSheet by remember { mutableStateOf(false) }
+    var hiddenTools by remember { mutableStateOf(loadPdfHiddenTools(context)) }
+
+    val onUpdateHiddenTools = { newSet: Set<String> ->
+        hiddenTools = newSet
+        savePdfHiddenTools(context, newSet)
+    }
+
     val executeWithOcrCheck = remember(hasSelectedOcrLanguage) {
         { action: () -> Unit ->
             if (hasSelectedOcrLanguage) {
@@ -3815,6 +3862,7 @@ fun PdfViewerScreen(
             showSummarizationUpsellDialog -> showSummarizationUpsellDialog = false
             showAiDefinitionPopup -> showAiDefinitionPopup = false
             showDictionaryUpsellDialog -> showDictionaryUpsellDialog = false
+            showCustomizeToolsSheet -> showCustomizeToolsSheet = false
             isPageSliderVisible -> {
                 isPageSliderVisible = false
                 showBars = true
@@ -5143,7 +5191,7 @@ fun PdfViewerScreen(
                                                     triggerAutoScrollTempPause(1000L)
 
                                                     coroutineScope.launch {
-                                                        verticalReaderState.scrollToPage(0)
+                                                        verticalReaderState.scrollToTop()
                                                     }
                                                     break
                                                 }
@@ -5210,7 +5258,7 @@ fun PdfViewerScreen(
                                                     triggerAutoScrollTempPause(1000L)
 
                                                     coroutineScope.launch {
-                                                        verticalReaderState.scrollToPage(totalPages - 1)
+                                                        verticalReaderState.scrollToBottom()
                                                     }
                                                     break
                                                 }
@@ -5555,6 +5603,7 @@ fun PdfViewerScreen(
                                             .testTag("PageNumberIndicator")
                                     )
 
+                                    if (!hiddenTools.contains(PdfReaderTool.THEME.name)) {
                                         TooltipIconButton(
                                             text = "Theme",
                                             description = "Theme Settings",
@@ -5565,7 +5614,9 @@ fun PdfViewerScreen(
                                                 tint = MaterialTheme.colorScheme.onSurfaceVariant
                                             )
                                         }
+                                    }
 
+                                    if (!hiddenTools.contains(PdfReaderTool.LOCK_PANNING.name)) {
                                         TooltipIconButton(
                                             text = if (isScrollLocked) stringResource(R.string.tooltip_unlock_pan)
                                             else stringResource(R.string.tooltip_lock_pan),
@@ -5585,7 +5636,9 @@ fun PdfViewerScreen(
                                                 tint = MaterialTheme.colorScheme.onSurfaceVariant
                                             )
                                         }
+                                    }
 
+                                    if (!hiddenTools.contains(PdfReaderTool.FULL_SCREEN.name)) {
                                         TooltipIconButton(
                                             text = stringResource(R.string.tooltip_fullscreen),
                                             description = stringResource(R.string.tooltip_fullscreen_desc),
@@ -5599,7 +5652,9 @@ fun PdfViewerScreen(
                                                 tint = MaterialTheme.colorScheme.onSurfaceVariant
                                             )
                                         }
+                                    }
 
+                                    if (!hiddenTools.contains(PdfReaderTool.DICTIONARY.name)) {
                                         TooltipIconButton(
                                             text = stringResource(R.string.tooltip_dictionary),
                                             description = stringResource(R.string.tooltip_dictionary_desc),
@@ -5610,6 +5665,7 @@ fun PdfViewerScreen(
                                                 tint = MaterialTheme.colorScheme.onSurfaceVariant
                                             )
                                         }
+                                    }
 
                                     if (BuildConfig.DEBUG) {
                                         TooltipIconButton(
@@ -5682,7 +5738,18 @@ fun PdfViewerScreen(
                                         DropdownMenu(
                                             expanded = showMoreMenu,
                                             onDismissRequest = { showMoreMenu = false }) {
-                                            if (BuildConfig.IS_PRO) {
+                                            DropdownMenuItem(
+                                                text = { Text("Customize Toolbar") },
+                                                onClick = {
+                                                    showMoreMenu = false
+                                                    showCustomizeToolsSheet = true
+                                                },
+                                                leadingIcon = {
+                                                    Icon(Icons.Default.Settings, contentDescription = null, modifier = Modifier.size(20.dp))
+                                                }
+                                            )
+                                            HorizontalDivider()
+                                            if (BuildConfig.IS_PRO && !hiddenTools.contains(PdfReaderTool.OCR_LANGUAGE.name)) {
                                                 DropdownMenuItem(
                                                     text = { Text("OCR Language") },
                                                     onClick = {
@@ -5693,6 +5760,7 @@ fun PdfViewerScreen(
                                                 HorizontalDivider()
                                             }
 
+                                            if (!hiddenTools.contains(PdfReaderTool.READING_MODE.name)) {
                                                 DropdownMenuItem(
                                                     text = { Text("Reading Mode: Vertical scroll") },
                                                     enabled = !isTtsSessionActive,
@@ -5725,6 +5793,8 @@ fun PdfViewerScreen(
                                                         }
                                                     })
                                                 HorizontalDivider()
+                                            }
+                                            if (!hiddenTools.contains(PdfReaderTool.KEEP_SCREEN_ON.name)) {
                                                 DropdownMenuItem(
                                                     text = { Text("Keep Screen On") },
                                                     onClick = {
@@ -5741,6 +5811,8 @@ fun PdfViewerScreen(
                                                         }
                                                     })
                                                 HorizontalDivider()
+                                            }
+                                            if (!hiddenTools.contains(PdfReaderTool.AUTO_SCROLL.name)) {
                                                 DropdownMenuItem(
                                                     text = { Text("Auto Scroll") },
                                                     enabled = !isTtsSessionActive && displayMode == DisplayMode.VERTICAL_SCROLL,
@@ -5752,6 +5824,8 @@ fun PdfViewerScreen(
                                                     })
 
                                                 HorizontalDivider()
+                                            }
+                                            if (!hiddenTools.contains(PdfReaderTool.TTS_SETTINGS.name)) {
                                                 DropdownMenuItem(
                                                     text = { Text("TTS Voice Settings") },
                                                     onClick = {
@@ -5764,7 +5838,8 @@ fun PdfViewerScreen(
                                                             contentDescription = null,
                                                             modifier = Modifier.size(20.dp)
                                                         )
-                                                })
+                                                    }
+                                                )
 
                                                 if (BuildConfig.DEBUG) {
                                                     DropdownMenuItem(
@@ -5779,10 +5854,12 @@ fun PdfViewerScreen(
                                                                 contentDescription = null,
                                                                 modifier = Modifier.size(20.dp)
                                                             )
-                                                    })
                                                         }
-
+                                                    )
+                                                }
                                                 HorizontalDivider()
+                                            }
+                                            if (!hiddenTools.contains(PdfReaderTool.BOOKMARK.name)) {
                                                 DropdownMenuItem(text = {
                                                     Text(
                                                         if (isBookmarked) "Remove bookmark"
@@ -5793,7 +5870,8 @@ fun PdfViewerScreen(
                                                     onBookmarkClick()
                                                 })
                                                 HorizontalDivider()
-
+                                            }
+                                            if (!hiddenTools.contains(PdfReaderTool.PAGE_MANAGEMENT.name)) {
                                                 DropdownMenuItem(
                                                     text = { Text("Insert Blank Page") },
                                                     onClick = {
@@ -5815,9 +5893,9 @@ fun PdfViewerScreen(
                                                         )
                                                     )
                                                 }
-
                                                 HorizontalDivider()
-
+                                            }
+                                            if (!hiddenTools.contains(PdfReaderTool.REFLOW.name)) {
                                                 DropdownMenuItem(
                                                     text = {
                                                         Text(
@@ -5850,8 +5928,7 @@ fun PdfViewerScreen(
                                                                     uiState.allRecentFiles.find { it.bookId == reflowBookId }
                                                                 if (item != null) {
                                                                     viewModel.switchToFileSeamlessly(
-                                                                    item,
+                                                                        item, resolvedPage
-                                                                    resolvedPage
                                                                     )
                                                                 } else {
                                                                     viewModel.generateAndImportReflowFile(
@@ -5878,18 +5955,24 @@ fun PdfViewerScreen(
                                                             modifier = Modifier.size(20.dp)
                                                         )
                                                     })
-
                                                 HorizontalDivider()
-
+                                            }
-                                            DropdownMenuItem(text = { Text("Share") }, onClick = {
+                                            if (!hiddenTools.contains(PdfReaderTool.SHARE.name)) {
+                                                DropdownMenuItem(
+                                                    text = { Text("Share") },
+                                                    onClick = {
                                                         showMoreMenu = false
                                                         showShareDialog = true
-                                            }, leadingIcon = {
+                                                    },
+                                                    leadingIcon = {
                                                         Icon(
-                                                    Icons.Default.Share, contentDescription = null
+                                                            Icons.Default.Share,
+                                                            contentDescription = null
                                                         )
-                                            })
+                                                    }
-                                            if (uiState.selectedFileType == FileType.PDF) {
+                                                )
+                                            }
+                                            if (uiState.selectedFileType == FileType.PDF && !hiddenTools.contains(PdfReaderTool.SAVE_COPY.name)) {
                                                 DropdownMenuItem(
                                                     text = { Text("Save copy to device") },
                                                     onClick = {
@@ -5903,7 +5986,7 @@ fun PdfViewerScreen(
                                                         )
                                                     })
                                             }
-                                            if (uiState.selectedFileType == FileType.PDF) {
+                                            if (uiState.selectedFileType == FileType.PDF && !hiddenTools.contains(PdfReaderTool.PRINT.name)) {
                                                 DropdownMenuItem(
                                                     text = { Text("Print") },
                                                     onClick = {
@@ -6247,11 +6330,13 @@ fun PdfViewerScreen(
                             horizontalArrangement = Arrangement.SpaceAround
                         ) {
                             // Slider Navigation Trigger
+                            if (!hiddenTools.contains(PdfReaderTool.SLIDER.name)) {
                                 TooltipIconButton(
                                     text = stringResource(R.string.tooltip_slider),
                                     description = stringResource(R.string.tooltip_slider_desc),
                                     onClick = {
-                                    val currentPage = if (displayMode == DisplayMode.PAGINATION) {
+                                        val currentPage =
+                                            if (displayMode == DisplayMode.PAGINATION) {
                                                 pagerState.currentPage
                                             } else {
                                                 verticalReaderState.currentPage
@@ -6260,14 +6345,16 @@ fun PdfViewerScreen(
                                         sliderCurrentPage = currentPage.toFloat()
                                         isPageSliderVisible = true
                                         showBars = false
-                                }, enabled = !(ttsState.isPlaying || ttsState.isLoading)
+                                    },
+                                    enabled = !(ttsState.isPlaying || ttsState.isLoading)
                                 ) {
                                     Icon(
                                         painter = painterResource(id = R.drawable.slider),
                                         contentDescription = "Navigate with slider"
                                     )
                                 }
-
+                            }
+                            if (!hiddenTools.contains(PdfReaderTool.TOC.name)) {
                                 TooltipIconButton(
                                     text = stringResource(R.string.tooltip_toc),
                                     description = stringResource(R.string.tooltip_toc_desc),
@@ -6280,8 +6367,10 @@ fun PdfViewerScreen(
                                         contentDescription = "Table of Contents"
                                     )
                                 }
+                            }
 
                             // Search Button
+                            if (!hiddenTools.contains(PdfReaderTool.SEARCH.name)) {
                                 TooltipIconButton(
                                     text = stringResource(R.string.tooltip_search),
                                     description = stringResource(R.string.tooltip_search_desc),
@@ -6299,16 +6388,13 @@ fun PdfViewerScreen(
                                         contentDescription = "Search"
                                     )
                                 }
-
+                            }
+                            if (!hiddenTools.contains(PdfReaderTool.HIGHLIGHT_ALL.name)) {
                                 TooltipIconButton(
-                                text = if (showAllTextHighlights)
+                                    text = if (showAllTextHighlights) stringResource(R.string.tooltip_highlights_off)
-                                    stringResource(R.string.tooltip_highlights_off)
+                                    else stringResource(R.string.tooltip_highlights),
-                                else
+                                    description = if (showAllTextHighlights) stringResource(R.string.tooltip_highlights_off_desc)
-                                    stringResource(R.string.tooltip_highlights),
+                                    else stringResource(R.string.tooltip_highlights_desc),
-                                description = if (showAllTextHighlights)
-                                    stringResource(R.string.tooltip_highlights_off_desc)
-                                else
-                                    stringResource(R.string.tooltip_highlights_desc),
                                     onClick = {
                                         val newState = !showAllTextHighlights
                                         if (newState) {
@@ -6331,9 +6417,10 @@ fun PdfViewerScreen(
                                         )
                                     }
                                 }
+                            }
 
                             // AI feat
-                            if (BuildConfig.FLAVOR != "oss") {
+                            if (BuildConfig.FLAVOR != "oss" && !hiddenTools.contains(PdfReaderTool.AI_FEATURES.name)) {
                                 Box {
                                     var showAiFeaturesMenu by remember { mutableStateOf(false) }
                                     TooltipIconButton(
@@ -6375,20 +6462,19 @@ fun PdfViewerScreen(
                             }
 
                             // Edit Button
+                            if (!hiddenTools.contains(PdfReaderTool.EDIT_MODE.name)) {
                                 TooltipIconButton(
-                                text = if (isEditMode)
+                                    text = if (isEditMode) stringResource(R.string.tooltip_edit_mode_exit)
-                                    stringResource(R.string.tooltip_edit_mode_exit)
+                                    else stringResource(R.string.tooltip_edit_mode),
-                                else
+                                    description = if (isEditMode) stringResource(R.string.tooltip_edit_mode_exit_desc)
-                                    stringResource(R.string.tooltip_edit_mode),
+                                    else stringResource(R.string.tooltip_edit_mode_desc),
-                                description = if (isEditMode)
-                                    stringResource(R.string.tooltip_edit_mode_exit_desc)
-                                else
-                                    stringResource(R.string.tooltip_edit_mode_desc),
                                     onClick = {
                                         val newEditMode = !isEditMode
-                                    val currentActivePage = richTextController?.activePageIndex ?: -1
+                                        val currentActivePage =
+                                            richTextController?.activePageIndex ?: -1
 
-                                    Timber.tag("RichTextMigration").i("Edit Toggle: $isEditMode -> $newEditMode (ActivePage: $currentActivePage)")
+                                        Timber.tag("RichTextMigration")
+                                            .i("Edit Toggle: $isEditMode -> $newEditMode (ActivePage: $currentActivePage)")
 
                                         if (!newEditMode && richTextController != null) {
                                             coroutineScope.launch {
@@ -6401,25 +6487,22 @@ fun PdfViewerScreen(
 
                                         isEditMode = newEditMode
                                         if (!newEditMode) showBars = true
-                                }
+                                    }) {
-                            ) {
                                     Icon(
                                         imageVector = Icons.Default.Edit,
                                         contentDescription = "Toggle Editing Mode",
                                         tint = if (isEditMode) MaterialTheme.colorScheme.primary else MaterialTheme.colorScheme.onSurfaceVariant
                                     )
                                 }
+                            }
 
                             // TTS
+                            if (!hiddenTools.contains(PdfReaderTool.TTS_CONTROLS.name)) {
                                 TooltipIconButton(
-                                text = if (isTtsSessionActive)
+                                    text = if (isTtsSessionActive) stringResource(R.string.tooltip_tts_stop)
-                                    stringResource(R.string.tooltip_tts_stop)
+                                    else stringResource(R.string.tooltip_tts_start),
-                                else
+                                    description = if (isTtsSessionActive) stringResource(R.string.tooltip_tts_stop_desc)
-                                    stringResource(R.string.tooltip_tts_start),
+                                    else stringResource(R.string.tooltip_tts_start_desc),
-                                description = if (isTtsSessionActive)
-                                    stringResource(R.string.tooltip_tts_stop_desc)
-                                else
-                                    stringResource(R.string.tooltip_tts_start_desc),
                                     onClick = {
                                         if (isTtsSessionActive) {
                                             Timber.d("TTS button clicked: Stopping TTS")
@@ -6436,6 +6519,7 @@ fun PdfViewerScreen(
                                         contentDescription = if (isTtsSessionActive) "Stop TTS" else "Start TTS"
                                     )
                                 }
+                            }
 
                             // TTS Pause/Resume Button
                             if (isTtsSessionActive) {
@@ -7759,7 +7843,22 @@ fun PdfViewerScreen(
                             savePdfAutoScrollUseSlider(context, autoScrollUseSlider)
                         },
                         isLocalMode = isAutoScrollLocal,
-                        onLocalModeToggle = onToggleAutoScrollMode
+                        onLocalModeToggle = onToggleAutoScrollMode,
+                        onScrollToTop = {
+                            if (isAutoScrollPlaying) {
+                                triggerAutoScrollTempPause(1000L)
+                            }
+                            coroutineScope.launch {
+                                verticalReaderState.scrollToTop()
+                            }
+                        }
+                    )
+                }
+                if (showCustomizeToolsSheet) {
+                    PdfCustomizeToolsSheet(
+                        hiddenTools = hiddenTools,
+                        onUpdate = onUpdateHiddenTools,
+                        onDismiss = { showCustomizeToolsSheet = false }
                     )
                 }
             }
@@ -8412,3 +8511,74 @@ fun PdfSearchResultsList(
         }
     }
 }
+
+@Composable
+fun PdfCustomizeToolsSheet(
+    hiddenTools: Set<String>,
+    onUpdate: (Set<String>) -> Unit,
+    onDismiss: () -> Unit
+) {
+    ModalBottomSheet(
+        onDismissRequest = onDismiss,
+        contentWindowInsets = { WindowInsets.navigationBars }
+    ) {
+        Column(modifier = Modifier.padding(horizontal = 24.dp).padding(bottom = 24.dp)) {
+            Text(
+                text = "Customize Toolbar",
+                style = MaterialTheme.typography.headlineSmall,
+                fontWeight = FontWeight.Bold,
+                color = MaterialTheme.colorScheme.onSurface
+            )
+            Spacer(modifier = Modifier.height(8.dp))
+            Text(
+                text = "Select the tools you want to keep visible. Unchecking a tool hides it from the UI to give you a distraction-free reading space.",
+                style = MaterialTheme.typography.bodyMedium,
+                color = MaterialTheme.colorScheme.onSurfaceVariant
+            )
+            Spacer(modifier = Modifier.height(16.dp))
+
+            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)
+                        )
+                    }
+                    items(tools) { tool ->
+                        Row(
+                            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)
+                                }
+                                .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)
+                                }
+                            )
+                        }
+                    }
+                }
+            }
+        }
+    }
+}

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

@@ -420,7 +420,7 @@ class PdfRichTextRepository(private val context: Context) {
                             isItalic = sObj.optBoolean("i"),
                             isUnderline = sObj.optBoolean("u"),
                             isStrikethrough = sObj.optBoolean("st"),
-                            fontPath = sObj.optString("fp", null),
+                            fontPath = sObj.optString("fp"),
                         )
                     )
                 }

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

@@ -200,8 +200,8 @@ object TextBoxSerializer {
                         isItalic = obj.optBoolean("isItalic", false),
                         isUnderline = obj.optBoolean("isUnderline", false),
                         isStrikeThrough = obj.optBoolean("isStrikeThrough", false),
-                        fontPath = obj.optString("fontPath", null).takeIf { !it.isNullOrBlank() },
+                        fontPath = obj.optString("fontPath").takeIf { !it.isNullOrBlank() },
-                        fontName = obj.optString("fontName", null).takeIf { !it.isNullOrBlank() }
+                        fontName = obj.optString("fontName").takeIf { !it.isNullOrBlank() }
                     )
                 )
             }
@@ -269,7 +269,7 @@ object HighlightSerializer {
                         color = try { PdfHighlightColor.valueOf(obj.getString("color")) } catch(_: Exception) { PdfHighlightColor.YELLOW },
                         text = obj.optString("text", ""),
                         range = Pair(obj.optInt("rangeStart", 0), obj.optInt("rangeEnd", 0)),
-                        note = obj.optString("note", null).takeIf { !it.isNullOrBlank() }
+                        note = obj.optString("note").takeIf { !it.isNullOrBlank() }
                     )
                 )
             }

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

@@ -139,6 +139,18 @@
     <string name="filter_source_folder">Source Folder</string>
     <string name="filter_read_status">Read Status</string>
     <string name="clear_all">Clear All</string>
+    <string name="filter_in_app_storage">In-App Storage</string>
+
+    <!-- External File Behavior -->
+    <string name="external_file_prompt_title">Save File?</string>
+    <string name="external_file_prompt_desc">Do you want to save this external file in the app\'s library? If not, it will be removed.\n\n(You can change this default behavior anytime from the Home Screen > More Options > External File Behavior).</string>
+    <string name="external_file_dont_ask">Don\'t ask again</string>
+    <string name="external_file_keep">Keep in Library</string>
+    <string name="external_file_delete">Remove</string>
+    <string name="external_file_behavior_ask">Ask Every Time</string>
+    <string name="external_file_behavior_keep">Always Keep</string>
+    <string name="external_file_behavior_delete">Always Remove</string>
+    <string name="options_external_file_behavior">External File Behavior</string>
 
     <!-- OPDS -->
     <string name="fab_add_catalog">Add Catalog</string>