package com.aryan.reader.epub import android.content.Context import android.graphics.BitmapFactory import android.util.Base64 import android.util.Xml import kotlinx.coroutines.Dispatchers import kotlinx.coroutines.withContext import org.jsoup.Jsoup import org.xmlpull.v1.XmlPullParser import timber.log.Timber import java.io.File import java.io.FileOutputStream import java.io.InputStream import java.util.zip.ZipInputStream class Fb2Parser(private val context: Context) { suspend fun createFb2Book( inputStream: InputStream, bookId: String, originalBookNameHint: String, parseContent: Boolean = true, extractionDirOverride: File? = null ): EpubBook = withContext(Dispatchers.IO) { val extractionDir = extractionDirOverride?.let(ImportedFileCache::prepareDirectory) ?: if (parseContent) { ImportedFileCache.prepareActiveBookDir(context, bookId) } else { ImportedFileCache.createTemporaryBookDir(context, bookId, "metadata") } var streamToParse = inputStream try { if (originalBookNameHint.endsWith(".zip", ignoreCase = true)) { val zis = ZipInputStream(inputStream) var entry = zis.nextEntry while (entry != null) { if (entry.name.endsWith(".fb2", ignoreCase = true)) { break } entry = zis.nextEntry } if (entry != null) { streamToParse = zis } else { throw Exception("No .fb2 file found inside the ZIP archive.") } } val parser = Xml.newPullParser() parser.setFeature(XmlPullParser.FEATURE_PROCESS_NAMESPACES, false) parser.setInput(streamToParse, null) var title = originalBookNameHint.substringBeforeLast(".") var author = "Unknown" var coverImageId: String? = null var coverBytes: ByteArray? = null val chapters = mutableListOf() val images = mutableListOf() // Keep track of extracted images var currentChapterHtml = StringBuilder() var currentChapterTitle = "Chapter 1" var chapterCount = 0 var inSection = false var inBody = false var inTitle = false val titleBuilder = java.lang.StringBuilder() // Buffer to handle

tags inside val cssStyle = """ body { font-family: sans-serif; line-height: 1.6; padding: 1em; max-width: 800px; margin: 0 auto; } p { margin-bottom: 1em; text-indent: 1.5em; text-align: justify; } h1, h2, h3, h4 { text-align: center; margin-top: 1.5em; margin-bottom: 1em; } .empty-line { height: 1.5em; } img { max-width: 100%; height: auto; display: block; margin: 1em auto; } .epigraph { margin-left: 2em; font-style: italic; margin-bottom: 1.5em; } .cite { border-left: 4px solid currentColor; padding-left: 1em; margin-left: 0; opacity: 0.8; font-style: italic; } .poem { margin: 1.5em 0; padding-left: 2em; } .stanza { margin-bottom: 1em; } """.trimIndent() fun saveChapter() { if (!parseContent || currentChapterHtml.isEmpty()) return chapterCount++ val fileName = "chapter_$chapterCount.html" val file = File(extractionDir, fileName) val fullHtml = """ <!DOCTYPE html> <html> <head> <title>${currentChapterTitle.replace("\"", """)} $currentChapterHtml """.trimIndent() FileOutputStream(file).use { it.write(fullHtml.toByteArray()) } val plainText = Jsoup.parse(fullHtml).text() chapters.add( EpubChapter( chapterId = "${bookId}_${chapterCount}", absPath = fileName, title = currentChapterTitle, htmlFilePath = fileName, plainTextContent = plainText, htmlContent = "", depth = 0, isInToc = true ) ) currentChapterHtml.clear() currentChapterTitle = "Chapter ${chapterCount + 1}" } var eventType = parser.eventType while (eventType != XmlPullParser.END_DOCUMENT) { when (eventType) { XmlPullParser.START_TAG -> { val name = parser.name.lowercase() when (name) { "book-title" -> { title = parser.nextText().trim() } "first-name", "last-name", "middle-name" -> { val namePart = parser.nextText().trim() if (namePart.isNotBlank()) { if (author == "Unknown") author = namePart else author += " $namePart" } } "body" -> { inBody = true } "section" -> { if (inBody) { if (currentChapterHtml.isNotBlank()) { saveChapter() } inSection = true } } "title" -> { if (inSection && currentChapterHtml.isEmpty()) { inTitle = true titleBuilder.clear() } currentChapterHtml.append("

") } "p" -> { if (!inTitle) { currentChapterHtml.append("

") } else if (titleBuilder.isNotEmpty()) { titleBuilder.append(" ") currentChapterHtml.append("
") } } "v" -> { if (!inTitle) { currentChapterHtml.append("

") } else if (titleBuilder.isNotEmpty()) { titleBuilder.append(" ") currentChapterHtml.append("
") } } "subtitle" -> currentChapterHtml.append("

") "empty-line" -> { if (!inTitle) { currentChapterHtml.append("
") } else if (titleBuilder.isNotEmpty()) { titleBuilder.append(" ") currentChapterHtml.append("
") } } "strong" -> currentChapterHtml.append("") "emphasis" -> currentChapterHtml.append("") "strikethrough" -> currentChapterHtml.append("") "sup" -> currentChapterHtml.append("") "sub" -> currentChapterHtml.append("") "epigraph" -> currentChapterHtml.append("
") "cite" -> currentChapterHtml.append("
") "poem" -> currentChapterHtml.append("
") "stanza" -> currentChapterHtml.append("
") "a" -> { val href = parser.getAttributeValue(null, "l:href") ?: parser.getAttributeValue(null, "xlink:href") ?: parser.getAttributeValue("http://www.w3.org/1999/xlink", "href") if (!inTitle) { if (href != null) { currentChapterHtml.append("") } else { currentChapterHtml.append("") } } } "image" -> { // Safely extract href checking all possible namespace stripped versions val href = parser.getAttributeValue(null, "l:href") ?: parser.getAttributeValue(null, "xlink:href") ?: parser.getAttributeValue("http://www.w3.org/1999/xlink", "href") ?: parser.getAttributeValue(null, "href") if (href != null) { val id = href.removePrefix("#") if (!inBody) { if (coverImageId == null) coverImageId = id } else { currentChapterHtml.append("") } } } "binary" -> { val id = parser.getAttributeValue(null, "id") if (id != null) { val base64Data = parser.nextText() try { val bytes = Base64.decode(base64Data, Base64.DEFAULT) if (parseContent) { val imgFile = File(extractionDir, id) FileOutputStream(imgFile).use { it.write(bytes) } } images.add(EpubImage(absPath = id)) if (id == coverImageId || (coverImageId == null && id.contains("cover", ignoreCase = true))) { coverBytes = bytes coverImageId = id } } catch (e: Exception) { Timber.e(e, "Failed to decode binary image $id") } } } } } XmlPullParser.TEXT -> { val text = parser.text?.replace("&", "&")?.replace("<", "<")?.replace(">", ">") if (!text.isNullOrBlank()) { if (inTitle) { titleBuilder.append(text) // Append to buffer since it could be split by

tags currentChapterHtml.append(text) } else if (inBody) { currentChapterHtml.append(text) } } } XmlPullParser.END_TAG -> { val name = parser.name.lowercase() when (name) { "body" -> { inBody = false } "title" -> { if (inTitle) { currentChapterTitle = titleBuilder.toString().replace("\\s+".toRegex(), " ").trim() if (currentChapterTitle.isBlank()) { currentChapterTitle = "Chapter ${chapterCount + 1}" } inTitle = false } currentChapterHtml.append("

\n") } "p", "v" -> if (!inTitle) currentChapterHtml.append("

\n") "subtitle" -> currentChapterHtml.append("\n") "strong" -> currentChapterHtml.append("") "emphasis" -> currentChapterHtml.append("") "strikethrough" -> currentChapterHtml.append("") "sup" -> currentChapterHtml.append("") "sub" -> currentChapterHtml.append("") "epigraph" -> currentChapterHtml.append("\n") "cite" -> currentChapterHtml.append("\n") "poem", "stanza" -> currentChapterHtml.append("\n") "a" -> if (!inTitle) currentChapterHtml.append("") } } } if (eventType != XmlPullParser.END_DOCUMENT) { eventType = parser.next() } } saveChapter() if (chapters.isEmpty() && parseContent) { if (currentChapterHtml.isNotBlank()) { saveChapter() } else { throw Exception("No valid content found in FB2 file.") } } val coverBitmap = coverBytes?.let { try { BitmapFactory.decodeByteArray(it, 0, it.size) } catch (e: Exception) { Timber.e(e, "Failed to decode cover bitmap for FB2") null } } return@withContext EpubBook( fileName = originalBookNameHint, title = title, author = author, language = "en", coverImage = coverBitmap, chapters = chapters, chaptersForPagination = chapters, images = images, pageList = emptyList(), tableOfContents = emptyList(), extractionBasePath = extractionDir.absolutePath, css = emptyMap() ) } finally { try { streamToParse.close() } catch (e: Exception) { Timber.e(e, "Error closing FB2 stream") } } } }