Support EPUB and TXT downloads from Kavita and BookOasis

app/src/main/java/eu/kanade/tachiyomi/data/download/DownloadCache.kt

@@ -376,8 +376,10 @@ class DownloadCache(
                                         it.name?.endsWith(Downloader.TMP_DIR_SUFFIX) == true -> null
                                         // Folder of images
                                         it.isDirectory -> it.name
-                                        // CBZ files
-                                        it.isFile && it.extension == "cbz" -> it.nameWithoutExtension
+                                        // Archived or original document files
+                                        it.isFile && it.extension?.lowercase()?.let { extension ->
+                                            extension == "cbz" || extension in DOCUMENT_DOWNLOAD_EXTENSIONS
+                                        } == true -> it.nameWithoutExtension
                                         // Anything else is irrelevant
                                         else -> null
                                     }

app/src/main/java/eu/kanade/tachiyomi/data/download/DownloadManager.kt

@@ -405,8 +405,12 @@ class DownloadManager(
             .firstOrNull() ?: return
 
         var newName = provider.getChapterDirName(newChapter.name, newChapter.scanlator, newChapter.url)
-        if (oldDownload.isFile && oldDownload.extension == "cbz") {
-            newName += ".cbz"
+        if (oldDownload.isFile) {
+            oldDownload.extension?.lowercase()?.let { extension ->
+                if (extension == "cbz" || extension in DOCUMENT_DOWNLOAD_EXTENSIONS) {
+                    newName += ".$extension"
+                }
+            }
         }
 
         if (oldDownload.name == newName) return

app/src/main/java/eu/kanade/tachiyomi/data/download/DownloadProvider.kt

@@ -19,6 +19,8 @@ import tachiyomi.domain.storage.service.StorageManager
 import tachiyomi.i18n.MR
 import java.io.IOException
 
+internal val DOCUMENT_DOWNLOAD_EXTENSIONS = setOf("epub", "txt")
+
 /**
  * This class is used to provide the directories where the downloads should be saved.
  * It uses the following path scheme: /<root downloads dir>/<source name>/<manga>/<chapter>
@@ -250,11 +252,17 @@ class DownloadProvider(
             add(chapterDirName)
             // Archived chapters
             add("$chapterDirName.cbz")
+            DOCUMENT_DOWNLOAD_EXTENSIONS.forEach { extension ->
+                add("$chapterDirName.$extension")
+            }
 
             // any legacy names
             legacyChapterDirNames.forEach {
                 add(it)
                 add("$it.cbz")
+                DOCUMENT_DOWNLOAD_EXTENSIONS.forEach { extension ->
+                    add("$it.$extension")
+                }
             }
         }
     }

app/src/main/java/eu/kanade/tachiyomi/data/download/Downloader.kt

@@ -12,8 +12,16 @@ import eu.kanade.tachiyomi.data.download.model.Download
 import eu.kanade.tachiyomi.data.library.LibraryUpdateNotifier
 import eu.kanade.tachiyomi.data.notification.NotificationHandler
 import eu.kanade.tachiyomi.network.HttpException
+import eu.kanade.tachiyomi.network.await
 import eu.kanade.tachiyomi.source.UnmeteredSource
+import eu.kanade.tachiyomi.source.bookoasis.bookOasisDocumentDownloadRequest
+import eu.kanade.tachiyomi.source.bookoasis.isBookOasisSource
+import eu.kanade.tachiyomi.source.bookoasis.toBookOasisChapterRef
 import eu.kanade.tachiyomi.source.model.Page
+import eu.kanade.tachiyomi.source.kavita.detectKavitaDocumentFormat
+import eu.kanade.tachiyomi.source.kavita.isKavitaSource
+import eu.kanade.tachiyomi.source.kavita.kavitaDocumentDownloadRequest
+import eu.kanade.tachiyomi.source.kavita.toKavitaChapterId
 import eu.kanade.tachiyomi.source.online.HttpSource
 import eu.kanade.tachiyomi.util.storage.DiskUtil
 import eu.kanade.tachiyomi.util.storage.DiskUtil.NOMEDIA_FILE
@@ -44,6 +52,7 @@ import kotlinx.coroutines.supervisorScope
 import logcat.LogPriority
 import mihon.core.archive.ZipWriter
 import nl.adaptivity.xmlutil.serialization.XML
+import okhttp3.Request
 import okhttp3.Response
 import tachiyomi.core.common.i18n.stringResource
 import tachiyomi.core.common.util.lang.launchIO
@@ -339,9 +348,15 @@ class Downloader(
             download.chapter.scanlator,
             download.chapter.url,
         )
-        val tmpDir = mangaDir.createDirectory(chapterDirname + TMP_DIR_SUFFIX)!!
-
         try {
+            val remoteDocument = findRemoteDocument(download)
+            if (remoteDocument != null) {
+                downloadDocument(download, mangaDir, chapterDirname, remoteDocument)
+                return
+            }
+
+            val tmpDir = mangaDir.createDirectory(chapterDirname + TMP_DIR_SUFFIX)!!
+
             // If the page list already exists, start from the file
             val pageList = download.pages ?: run {
                 // Otherwise, pull page list from network and add them to download object
@@ -415,6 +430,84 @@ class Downloader(
         }
     }
 
+    private suspend fun findRemoteDocument(download: Download): RemoteDocument? {
+        val source = download.source
+        return when {
+            source.isBookOasisSource() -> download.chapter.url
+                .toBookOasisChapterRef()
+                ?.takeIf { it.format in DOCUMENT_DOWNLOAD_EXTENSIONS }
+                ?.let { ref -> RemoteDocument(ref.format, source.bookOasisDocumentDownloadRequest(ref)) }
+            source.isKavitaSource() -> download.chapter.url
+                .toKavitaChapterId()
+                ?.let { chapterId ->
+                    source.detectKavitaDocumentFormat(chapterId)?.let { format ->
+                        RemoteDocument(format, source.kavitaDocumentDownloadRequest(chapterId))
+                    }
+                }
+            else -> null
+        }
+    }
+
+    private suspend fun downloadDocument(
+        download: Download,
+        mangaDir: UniFile,
+        chapterDirname: String,
+        document: RemoteDocument,
+    ) {
+        val targetName = "$chapterDirname.${document.extension}"
+        mangaDir.findFile(targetName)?.delete()
+        mangaDir.findFile("$targetName.tmp")?.delete()
+        val temp = mangaDir.createFile("$targetName.tmp")
+            ?: error("Failed to create temporary document file")
+        val page = Page(0).apply {
+            status = Page.State.DownloadImage
+        }
+        download.pages = listOf(page)
+        download.status = Download.State.DOWNLOADING
+        notifier.onProgressChange(download)
+
+        try {
+            download.source.client.newCall(document.request).await().use { response ->
+                if (!response.isSuccessful) {
+                    throw IllegalStateException(
+                        "Document download failed: HTTP ${response.code}",
+                    )
+                }
+                temp.openOutputStream().use { output ->
+                    response.body.byteStream().use { input -> input.copyTo(output) }
+                }
+            }
+
+            if (temp.length() <= 0L) {
+                throw IllegalStateException("Document download returned an empty file")
+            }
+
+            if (!temp.renameTo(targetName)) {
+                val target = mangaDir.createFile(targetName)
+                    ?: error("Failed to create downloaded document file")
+                temp.openInputStream().use { input ->
+                    target.openOutputStream().use { output ->
+                        input.copyTo(output)
+                    }
+                }
+                temp.delete()
+            }
+        } catch (error: Throwable) {
+            temp.delete()
+            throw error
+        }
+
+        val target = mangaDir.findFile(targetName)
+            ?: error("Downloaded document file is missing")
+        page.uri = target.uri
+        page.status = Page.State.Ready
+        page.progress = 100
+        notifier.onProgressChange(download)
+        cache.addChapter(chapterDirname, mangaDir, download.manga)
+        DiskUtil.createNoMediaFile(mangaDir, context)
+        download.status = Download.State.DOWNLOADED
+    }
+
     /**
      * Gets the image from the filesystem if it exists or downloads it otherwise.
      *
@@ -740,5 +833,10 @@ class Downloader(
     }
 }
 
+private data class RemoteDocument(
+    val extension: String,
+    val request: Request,
+)
+
 // Arbitrary minimum required space to start a download: 200 MB
 private const val MIN_DISK_SPACE = 200L * 1024 * 1024

app/src/main/java/eu/kanade/tachiyomi/source/bookoasis/BookOasisCompat.kt

@@ -21,6 +21,22 @@ internal data class BookOasisChapterRef(
     val format: String,
 )
 
+internal fun HttpSource.bookOasisDocumentDownloadRequest(ref: BookOasisChapterRef): Request {
+    val downloadUrl = buildString {
+        append(baseUrl.trimEnd('/'))
+        append("/api/media/books/")
+        append(ref.bookId)
+        append("/download?type=")
+        append(ref.dbType)
+    }
+
+    return Request.Builder()
+        .url(downloadUrl)
+        .headers(headers)
+        .get()
+        .build()
+}
+
 internal fun Source.isBookOasisSource(): Boolean {
     return this::class.java.name.startsWith(BOOKOASIS_PACKAGE_PREFIX)
 }

app/src/main/java/eu/kanade/tachiyomi/source/kavita/KavitaCompat.kt

@@ -1,12 +1,56 @@
 package eu.kanade.tachiyomi.source.kavita
 
+import eu.kanade.tachiyomi.network.await
 import eu.kanade.tachiyomi.source.Source
+import eu.kanade.tachiyomi.source.online.HttpSource
+import okhttp3.Request
+import org.json.JSONObject
+import java.util.Locale
 
 private const val KAVITA_PACKAGE_PREFIX = "eu.kanade.tachiyomi.extension.all.kavita."
 
 internal fun Source.isKavitaSource(): Boolean =
     this::class.java.name.startsWith(KAVITA_PACKAGE_PREFIX)
 
+internal suspend fun HttpSource.detectKavitaDocumentFormat(chapterId: Int): String? {
+    val apiBase = baseUrl.trimEnd('/') + "/api"
+    val request = Request.Builder()
+        .url("$apiBase/Chapter?chapterId=$chapterId")
+        .headers(headers)
+        .get()
+        .build()
+
+    client.newCall(request).await().use { response ->
+        if (!response.isSuccessful) return null
+
+        val body = response.body.string()
+        if (body.isBlank()) return null
+
+        val files = JSONObject(body).optJSONArray("files") ?: return null
+        for (i in 0 until files.length()) {
+            val file = files.optJSONObject(i) ?: continue
+            val extension = file.optString("extension")
+                .ifBlank { file.optString("filePath") }
+                .substringAfterLast('.')
+                .trim()
+                .trimStart('.')
+                .lowercase(Locale.ROOT)
+            if (extension == "epub" || extension == "txt") return extension
+            if (file.optInt("format", -1) == 3) return "epub"
+        }
+    }
+    return null
+}
+
+internal fun HttpSource.kavitaDocumentDownloadRequest(chapterId: Int): Request {
+    val apiBase = baseUrl.trimEnd('/') + "/api"
+    return Request.Builder()
+        .url("$apiBase/Download/chapter?chapterId=$chapterId")
+        .headers(headers)
+        .get()
+        .build()
+}
+
 /**
  * Kavita extension chapter URLs are normally /Chapter/{id}. Keep compatibility
  * with older/alternate forms used by reading lists and previous releases.

app/src/main/java/eu/kanade/tachiyomi/ui/reader/loader/BookOasisFilePageLoader.kt

@@ -4,11 +4,11 @@ import android.content.Context
 import com.hippo.unifile.UniFile
 import eu.kanade.tachiyomi.network.await
 import eu.kanade.tachiyomi.source.bookoasis.BookOasisChapterRef
+import eu.kanade.tachiyomi.source.bookoasis.bookOasisDocumentDownloadRequest
 import eu.kanade.tachiyomi.source.online.HttpSource
 import eu.kanade.tachiyomi.ui.reader.model.ReaderPage
 import eu.kanade.tachiyomi.ui.reader.setting.TextReaderStyle
 import mihon.core.archive.epubReader
-import okhttp3.Request
 import java.io.File
 import java.io.IOException
 
@@ -68,19 +68,7 @@ internal class BookOasisFilePageLoader(
         val temp = File(cacheDir, "${target.name}.part")
         if (temp.exists()) temp.delete()
 
-        val downloadUrl = buildString {
-            append(source.baseUrl.trimEnd('/'))
-            append("/api/media/books/")
-            append(ref.bookId)
-            append("/download?type=")
-            append(ref.dbType)
-        }
-
-        val request = Request.Builder()
-            .url(downloadUrl)
-            .headers(source.headers)
-            .get()
-            .build()
+        val request = source.bookOasisDocumentDownloadRequest(ref)
 
         source.client.newCall(request).await().use { response ->
             if (!response.isSuccessful) {

app/src/main/java/eu/kanade/tachiyomi/ui/reader/loader/DownloadPageLoader.kt

@@ -11,7 +11,10 @@ import eu.kanade.tachiyomi.source.model.Page
 import eu.kanade.tachiyomi.ui.reader.model.ReaderChapter
 import eu.kanade.tachiyomi.ui.reader.model.ReaderPage
 import mihon.core.archive.archiveReader
+import mihon.core.archive.epubReader
+import tachiyomi.core.common.storage.extension
 import tachiyomi.domain.manga.model.Manga
+import eu.kanade.tachiyomi.ui.reader.setting.ReaderPreferences
 import uy.kohesive.injekt.injectLazy
 
 /**
@@ -27,9 +30,12 @@ internal class DownloadPageLoader(
 
     private val context: Context by injectLazy()
 
-    private var archivePageLoader: ArchivePageLoader? = null
+    private var pageLoader: PageLoader? = null
+    private val readerPreferences: ReaderPreferences by injectLazy()
 
     override var isLocal: Boolean = true
+    override val usesTextReaderStyle: Boolean
+        get() = pageLoader?.usesTextReaderStyle == true
 
     override suspend fun getPages(): List<ReaderPage> {
         val dbChapter = chapter.chapter
@@ -41,7 +47,11 @@ internal class DownloadPageLoader(
             source,
         )
         return if (chapterPath?.isFile == true) {
-            getPagesFromArchive(chapterPath)
+            when (chapterPath.extension?.lowercase()) {
+                "epub" -> getPagesFromEpub(chapterPath)
+                "txt" -> getPagesFromText(chapterPath)
+                else -> getPagesFromArchive(chapterPath)
+            }
         } else {
             getPagesFromDirectory()
         }
@@ -49,11 +59,30 @@ internal class DownloadPageLoader(
 
     override fun recycle() {
         super.recycle()
-        archivePageLoader?.recycle()
+        pageLoader?.recycle()
+        pageLoader = null
     }
 
     private suspend fun getPagesFromArchive(file: UniFile): List<ReaderPage> {
-        val loader = ArchivePageLoader(file.archiveReader(context)).also { archivePageLoader = it }
+        val loader = ArchivePageLoader(file.archiveReader(context)).also { pageLoader = it }
+        return loader.getPages()
+    }
+
+    private suspend fun getPagesFromEpub(file: UniFile): List<ReaderPage> {
+        val loader = EpubPageLoader(
+            file.epubReader(context),
+            readerPreferences.textReaderStyle(context),
+            context.cacheDir,
+        ).also { pageLoader = it }
+        return loader.getPages()
+    }
+
+    private suspend fun getPagesFromText(file: UniFile): List<ReaderPage> {
+        val loader = TextPageLoader(
+            file,
+            readerPreferences.textReaderStyle(context),
+            context.cacheDir,
+        ).also { pageLoader = it }
         return loader.getPages()
     }
 
@@ -69,6 +98,6 @@ internal class DownloadPageLoader(
     }
 
     override suspend fun loadPage(page: ReaderPage) {
-        archivePageLoader?.loadPage(page)
+        pageLoader?.loadPage(page)
     }
 }

app/src/main/java/eu/kanade/tachiyomi/ui/reader/loader/KavitaCompatPageLoader.kt

@@ -4,16 +4,15 @@ import android.content.Context
 import com.hippo.unifile.UniFile
 import eu.kanade.tachiyomi.data.cache.ChapterCache
 import eu.kanade.tachiyomi.network.await
+import eu.kanade.tachiyomi.source.kavita.detectKavitaDocumentFormat
+import eu.kanade.tachiyomi.source.kavita.kavitaDocumentDownloadRequest
 import eu.kanade.tachiyomi.source.online.HttpSource
 import eu.kanade.tachiyomi.ui.reader.model.ReaderChapter
 import eu.kanade.tachiyomi.ui.reader.model.ReaderPage
 import eu.kanade.tachiyomi.ui.reader.setting.TextReaderStyle
 import mihon.core.archive.epubReader
-import okhttp3.Request
-import org.json.JSONObject
 import java.io.File
 import java.io.IOException
-import java.util.Locale
 
 /**
  * Compatibility loader for Kavita document chapters.
@@ -42,7 +41,7 @@ internal class KavitaCompatPageLoader(
     override suspend fun getPages(): List<ReaderPage> {
         check(!isRecycled)
 
-        val format = detectDocumentFormat()
+        val format = source.detectKavitaDocumentFormat(chapterId)
         val loader = when (format) {
             "epub", "txt" -> createDocumentLoader(format)
             else -> HttpPageLoader(chapter, source, chapterCache)
@@ -67,51 +66,6 @@ internal class KavitaCompatPageLoader(
         super.recycle()
     }
 
-    private suspend fun detectDocumentFormat(): String? {
-        val apiBase = source.baseUrl.trimEnd('/') + "/api"
-        val request = Request.Builder()
-            .url("$apiBase/Chapter?chapterId=$chapterId")
-            .headers(source.headers)
-            .get()
-            .build()
-
-        source.client.newCall(request).await().use { response ->
-            if (!response.isSuccessful) {
-                // Preserve the extension's normal behavior when chapter metadata
-                // cannot be queried. It may still be readable as image content.
-                return null
-            }
-
-            val body = response.body.string()
-            if (body.isBlank()) return null
-
-            val chapterJson = JSONObject(body)
-            val files = chapterJson.optJSONArray("files") ?: return null
-            for (i in 0 until files.length()) {
-                val file = files.optJSONObject(i) ?: continue
-                val extension = normalizeExtension(
-                    file.optString("extension").ifBlank { file.optString("filePath") },
-                )
-                if (extension == "epub" || extension == "txt") {
-                    return extension
-                }
-
-                // Current Kavita format enum: EPUB == 3. TXT has no dedicated
-                // enum value in upstream Kavita, so it is detected by extension.
-                if (file.optInt("format", -1) == 3) {
-                    return "epub"
-                }
-            }
-        }
-        return null
-    }
-
-    private fun normalizeExtension(value: String): String =
-        value.substringAfterLast('.', value)
-            .trim()
-            .trimStart('.')
-            .lowercase(Locale.ROOT)
-
     private suspend fun createDocumentLoader(format: String): PageLoader {
         val file = getOrDownloadDocument(format)
         val uniFile = UniFile.fromFile(file)
@@ -132,12 +86,7 @@ internal class KavitaCompatPageLoader(
         val temp = File(cacheDir, "${target.name}.part")
         if (temp.exists()) temp.delete()
 
-        val apiBase = source.baseUrl.trimEnd('/') + "/api"
-        val request = Request.Builder()
-            .url("$apiBase/Download/chapter?chapterId=$chapterId")
-            .headers(source.headers)
-            .get()
-            .build()
+        val request = source.kavitaDocumentDownloadRequest(chapterId)
 
         source.client.newCall(request).await().use { response ->
             if (!response.isSuccessful) {