Txt file fix (#35)

* Fixed virtualization data indexing and improved text file to EPUB conversion logic.

- Corrected array indexing for `chunksData` and `chunkHeights` in `epub_reader.js` to prevent overwriting entire arrays.
- Refined virtualization intersection observer to properly restore and unload chunk content using index-based caching.
- Updated `SingleFileImporter.kt` to convert plain text into structured HTML paragraphs instead of a single `pre` tag.
- Enhanced CSS styles for imported single-file documents and added HTML entity escaping.

* Adjusted text layout and enhanced pagination mismatch logging

*   Configured `PlatformTextStyle` and `LineHeightStyle` to improve text measurement consistency.
*   Updated `checkLayoutMismatch` to include text snippets and handle zero expected height.
*   Refined `Modifier` application order in the reader view.
*   Ensured `maxHeight` is set to `Infinity` during text measurement in `Paginator`.

app/build.gradle.kts

@@ -20,6 +20,7 @@ if (localPropertiesFile.exists()) {
 android {
     namespace = "com.aryan.reader"
     compileSdk = 35
+    ndkVersion = "29.0.14206865"
 
     defaultConfig {
         applicationId = "com.aryan.reader"

app/src/main/assets/epub_reader.js

@@ -1820,15 +1820,7 @@
         observer: null,
 
         init: function (initialChunkIndex, total) {
-            console.log(`Virtualization: Init with $ {
+            console.log(`Virtualization: Init with ${total} chunks. Anchor: ${initialChunkIndex}`);
-                        total
-                    }
-
-                    chunks. Anchor: $ {
-                        initialChunkIndex
-                    }
-
-                    `);
             this.totalChunks = total;
             this.chunksData = new Array(total).fill(null);
             this.chunkHeights = new Array(total).fill(0);
@@ -1838,11 +1830,12 @@
             if (container) {
                 container.querySelectorAll(".chunk-container").forEach((div) => {
                     let idx = parseInt(div.dataset.chunkIndex, 10);
-                    let content = div.innerHTML.trim();
+                    let content = div.innerHTML; // Don't trim, keep original HTML structure
 
-                    if (content.length > 0) {
+                    if (content.trim().length > 0) {
-                        this.chunksData = content;
+                        // FIX: Assign to specific index, don't overwrite the whole array
-                        this.chunkHeights = div.getBoundingClientRect().height;
+                        this.chunksData[idx] = content;
+                        this.chunkHeights[idx] = div.getBoundingClientRect().height;
                     }
                 });
             }
@@ -1862,26 +1855,31 @@
                         let idx = parseInt(div.dataset.chunkIndex, 10);
 
                         if (entry.isIntersecting) {
-                            if (!this.chunksData) {
+                            // Check if we have data for this chunk at specific index
+                            if (!this.chunksData[idx]) {
                                 if (window.ContentBridge && window.ContentBridge.requestChunk) {
                                     window.ContentBridge.requestChunk(idx);
                                 }
                             } else if (div.innerHTML === "") {
+                                // Restore content from cache
                                 let oldHeight = div.getBoundingClientRect().height;
-                                div.innerHTML = this.chunksData;
+                                div.innerHTML = this.chunksData[idx]; // FIX: Access by index
-                                div.style.height = "";
+                                div.style.height = ""; // Allow auto height
-                                let newHeight = div.getBoundingClientRect().height;
-                                this.chunkHeights = newHeight;
 
+                                let newHeight = div.getBoundingClientRect().height;
+                                this.chunkHeights[idx] = newHeight; // Update cached height
+
+                                // Adjust scroll if this expansion happened above our viewport
                                 if (div.getBoundingClientRect().top < 0) {
-                                    scrollAdjust += newHeight - oldHeight;
+                                    scrollAdjust += (newHeight - oldHeight);
                                 }
                             }
                         } else {
+                            // Unload content to save memory/DOM weight
                             if (div.innerHTML !== "") {
                                 let oldHeight = div.getBoundingClientRect().height;
-                                this.chunkHeights = oldHeight;
+                                this.chunkHeights[idx] = oldHeight;
-                                div.style.height = oldHeight + "px";
+                                div.style.height = oldHeight + "px"; // Fix height to placeholder
                                 div.innerHTML = "";
                             }
                         }
@@ -1891,8 +1889,7 @@
                         window.scrollBy(0, scrollAdjust);
                     }
                 },
-
+                { rootMargin: "2500px 0px" } // Keep large margin for smooth scrolling
-                { rootMargin: "2500px 0px" },
             );
 
             document.querySelectorAll(".chunk-container").forEach((div) => {

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

@@ -105,17 +105,8 @@ class SingleFileImporter(private val context: Context) {
         var chapterCounter = 1
 
         val cssStyle = """
-            body { margin: 0; padding: 0; }
+            body { font-family: sans-serif; line-height: 1.6; padding: 1em; max-width: 800px; margin: 0 auto; }
-            pre { 
+            p { margin-bottom: 1em; text-indent: 1.5em; }
-                font-family: 'Courier New', Courier, monospace; 
-                font-size: 1em;
-                line-height: 1.5;
-                white-space: pre-wrap; 
-                overflow-wrap: anywhere; 
-                word-break: break-word;
-                padding: 1em;
-                margin: 0;
-            }
         """.trimIndent()
 
         val currentChapterContent = StringBuilder()
@@ -135,7 +126,9 @@ class SingleFileImporter(private val context: Context) {
                     <title>$chapterTitle</title>
                     <style>$cssStyle</style>
                 </head>
-                <body><pre>${currentChapterContent}</pre></body>
+                <body>
+                $currentChapterContent
+                </body>
                 </html>
             """.trimIndent()
 
@@ -160,37 +153,55 @@ class SingleFileImporter(private val context: Context) {
             chapterCounter++
         }
 
+        fun escapeHtml(text: String): String {
+            return text.replace("&", "&amp;")
+                .replace("<", "&lt;")
+                .replace(">", "&gt;")
+        }
+
         val reader = inputStream.bufferedReader()
-        val buffer = CharArray(8192)
+        var inParagraph = false
 
         while (true) {
-            val readCount = reader.read(buffer)
+            val line = reader.readLine()
-            if (readCount == -1) break
+            if (line == null) {
-
+                if (inParagraph) {
-            for (i in 0 until readCount) {
+                    currentChapterContent.append("</p>\n")
-                val c = buffer[i]
-
-                if ((c < ' ' && c != '\t' && c != '\n' && c != '\r')) {
-                    continue
-                }
-
-                when (c) {
-                    '<' -> currentChapterContent.append("&lt;")
-                    '>' -> currentChapterContent.append("&gt;")
-                    '&' -> currentChapterContent.append("&amp;")
-                    else -> currentChapterContent.append(c)
                 }
+                break
             }
 
-            if (currentChapterContent.length >= chapterTargetSize) {
+            val trimmed = line.trim()
-                flushChapter()
+            if (trimmed.isEmpty()) {
+                if (inParagraph) {
+                    currentChapterContent.append("</p>\n")
+                    inParagraph = false
+                }
+
+                if (currentChapterContent.length >= chapterTargetSize) {
+                    flushChapter()
+                }
+            } else {
+                if (!inParagraph) {
+                    currentChapterContent.append("<p>")
+                    inParagraph = true
+                } else {
+                    currentChapterContent.append(" ")
+                }
+                currentChapterContent.append(escapeHtml(trimmed))
+
+                if (currentChapterContent.length >= chapterTargetSize * 2) {
+                    currentChapterContent.append("</p>\n")
+                    flushChapter()
+                    inParagraph = false
+                }
             }
         }
 
         flushChapter()
 
         if (chapters.isEmpty()) {
-            currentChapterContent.append("(Empty File)")
+            currentChapterContent.append("<p>(Empty File)</p>")
             flushChapter()
         }
 

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

@@ -31,6 +31,8 @@ import android.widget.Toast
 import androidx.annotation.RequiresApi
 import androidx.compose.foundation.BorderStroke
 import androidx.compose.foundation.ExperimentalFoundationApi
+import androidx.compose.ui.text.PlatformTextStyle
+import androidx.compose.ui.text.style.LineHeightStyle
 import androidx.compose.foundation.background
 import androidx.compose.foundation.border
 import androidx.compose.foundation.clickable
@@ -544,7 +546,12 @@ fun PaginatedReaderScreen(
                 lineHeight = adjustedLineHeight,
                 fontFamily = debouncedFontFamily,
                 lineBreak = LineBreak.Paragraph,
-                letterSpacing = TextUnit.Unspecified
+                letterSpacing = TextUnit.Unspecified,
+                platformStyle = PlatformTextStyle(includeFontPadding = false),
+                lineHeightStyle = LineHeightStyle(
+                    alignment = LineHeightStyle.Alignment.Proportional,
+                    trim = LineHeightStyle.Trim.None
+                )
             )
         }
 
@@ -1302,15 +1309,22 @@ private fun checkLayoutMismatch(
     blockType: String,
     expectedHeight: Int,
     actualHeight: Int,
-    tolerance: Int = 2
+    textSnippet: String,
+    @Suppress("SameParameterValue") tolerance: Int = 2
 ) {
+    if (expectedHeight == 0) {
+        Timber.tag("PAGINATION_MISMATCH").w("Block #$blockIndex ($blockType) has expectedHeight=0. Skipping check. Text: '$textSnippet'")
+        return
+    }
+
     if (actualHeight > expectedHeight + tolerance) {
         val diff = actualHeight - expectedHeight
         Timber.tag("PAGINATION_MISMATCH").e(
             "OVERFLOW DETECTED! Block #$blockIndex ($blockType)\n" +
                     " -> Expected: ${expectedHeight}px\n" +
                     " -> Actual:   ${actualHeight}px\n" +
-                    " -> Diff:     +${diff}px"
+                    " -> Diff:     +${diff}px\n" +
+                    " -> Content:  '$textSnippet'"
         )
     }
 }
@@ -1560,8 +1574,7 @@ internal fun PaginatedReaderContent(
                                                 Modifier.fillMaxWidth()
                                             }
 
-                                            val boxModifier = marginModifier
+                                            val styleModifier = alignModifier
-                                                .then(alignModifier)
                                                 .then(if (block.style.horizontalAlign == "center") widthModifier else Modifier)
                                                 .then(
                                                     if (block.style.borderRadius > 0.dp) Modifier.clip(RoundedCornerShape(block.style.borderRadius))
@@ -1588,15 +1601,27 @@ internal fun PaginatedReaderContent(
                                                 .onGloballyPositioned { coordinates ->
                                                     val actualHeight = coordinates.size.height
                                                     if (block.expectedHeight > 0) {
+                                                        val snippet = when(block) {
+                                                            is ParagraphBlock -> block.content.text.take(50)
+                                                            is HeaderBlock -> block.content.text.take(50)
+                                                            is QuoteBlock -> block.content.text.take(50)
+                                                            is ListItemBlock -> block.content.text.take(50)
+                                                            is TextContentBlock -> block.content.text.take(50)
+                                                            else -> "Non-text content"
+                                                        }
+
                                                         checkLayoutMismatch(
                                                             blockIndex = block.blockIndex,
                                                             blockType = block::class.simpleName ?: "Block",
                                                             expectedHeight = block.expectedHeight,
-                                                            actualHeight = actualHeight
+                                                            actualHeight = actualHeight,
+                                                            textSnippet = snippet,
+                                                            tolerance = 2
                                                         )
                                                     }
                                                 }
-                                                .then(boxModifier)
+                                                .then(marginModifier)
+                                                .then(styleModifier)
 
                                             Box(modifier = diagnosticModifier) {
                                                 val borderWidth = block.style.border?.width ?: 0.dp

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

@@ -710,7 +710,8 @@ private suspend fun measureBlockHeight(
     }
 
     val adjustedConstraints = constraints.copy(
-        maxWidth = contentMaxWidth.roundToInt().coerceAtLeast(0)
+        maxWidth = contentMaxWidth.roundToInt().coerceAtLeast(0),
+        maxHeight = Constraints.Infinity
     )
 
     val contentHeight = when (block) {
@@ -1021,7 +1022,7 @@ private suspend fun splitParagraphBlock(
         textMeasurer.measure(
             text = text,
             style = textStyle,
-            constraints = constraints
+            constraints = constraints.copy(maxHeight = Constraints.Infinity)
         )
     }