Always return "ArchiveProvider" in case "downloadAsCbz" is enabled (#671)

* Move chapter download logic to base class

* Do not reuse "FolderProvider" in "ArchiveProviders" download function

Due to reusing the "FolderProvider" to download a chapter as a cbz file, a normal chapter download folder was created.
In case the download was aborted before the cbz file got created and the folder deleted, the next time the chapter got downloaded, the wrong "FileProvider" was selected, causing the chapter not to get downloaded as a cbz file.

server/src/main/kotlin/suwayomi/tachidesk/manga/impl/download/fileProvider/ChaptersFilesProvider.kt

@@ -1,7 +1,16 @@
 package suwayomi.tachidesk.manga.impl.download.fileProvider
 
 import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.FlowPreview
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.flow.distinctUntilChanged
+import kotlinx.coroutines.flow.launchIn
+import kotlinx.coroutines.flow.onEach
+import kotlinx.coroutines.flow.sample
+import suwayomi.tachidesk.manga.impl.Page
 import suwayomi.tachidesk.manga.impl.download.model.DownloadChapter
+import suwayomi.tachidesk.manga.impl.util.getChapterCachePath
+import java.io.File
 import java.io.InputStream
 
 /*
@@ -14,11 +23,46 @@ abstract class ChaptersFilesProvider(val mangaId: Int, val chapterId: Int) : Dow
         return RetrieveFile1Args(::getImageImpl)
     }
 
-    abstract suspend fun downloadImpl(
+    @OptIn(FlowPreview::class)
+    open suspend fun downloadImpl(
         download: DownloadChapter,
         scope: CoroutineScope,
         step: suspend (DownloadChapter?, Boolean) -> Unit
-    ): Boolean
+    ): Boolean {
+        val pageCount = download.chapter.pageCount
+        val chapterDir = getChapterCachePath(mangaId, chapterId)
+        val folder = File(chapterDir)
+        folder.mkdirs()
+
+        for (pageNum in 0 until pageCount) {
+            var pageProgressJob: Job? = null
+            val fileName = Page.getPageName(pageNum) // might have to change this to index stored in database
+            if (File(folder, fileName).exists()) continue
+            try {
+                Page.getPageImage(
+                    mangaId = download.mangaId,
+                    chapterIndex = download.chapterIndex,
+                    index = pageNum
+                ) { flow ->
+                    pageProgressJob = flow
+                        .sample(100)
+                        .distinctUntilChanged()
+                        .onEach {
+                            download.progress = (pageNum.toFloat() + (it.toFloat() * 0.01f)) / pageCount
+                            step(null, false) // don't throw on canceled download here since we can't do anything
+                        }
+                        .launchIn(scope)
+                }
+            } finally {
+                // always cancel the page progress job even if it throws an exception to avoid memory leaks
+                pageProgressJob?.cancel()
+            }
+            // TODO: retry on error with 2,4,8 seconds of wait
+            download.progress = ((pageNum + 1).toFloat()) / pageCount
+            step(download, false)
+        }
+        return true
+    }
 
     override fun download(): FileDownload3Args<DownloadChapter, CoroutineScope, suspend (DownloadChapter?, Boolean) -> Unit> {
         return FileDownload3Args(::downloadImpl)

server/src/main/kotlin/suwayomi/tachidesk/manga/impl/download/fileProvider/impl/ArchiveProvider.kt

@@ -9,8 +9,8 @@ import org.apache.commons.compress.archivers.zip.ZipArchiveOutputStream
 import org.apache.commons.compress.archivers.zip.ZipFile
 import suwayomi.tachidesk.manga.impl.download.fileProvider.ChaptersFilesProvider
 import suwayomi.tachidesk.manga.impl.download.model.DownloadChapter
+import suwayomi.tachidesk.manga.impl.util.getChapterCachePath
 import suwayomi.tachidesk.manga.impl.util.getChapterCbzPath
-import suwayomi.tachidesk.manga.impl.util.getChapterDownloadPath
 import java.io.File
 import java.io.InputStream
 
@@ -29,20 +29,19 @@ class ArchiveProvider(mangaId: Int, chapterId: Int) : ChaptersFilesProvider(mang
         scope: CoroutineScope,
         step: suspend (DownloadChapter?, Boolean) -> Unit
     ): Boolean {
-        val chapterDir = getChapterDownloadPath(mangaId, chapterId)
         val outputFile = File(getChapterCbzPath(mangaId, chapterId))
-        val chapterFolder = File(chapterDir)
+        val chapterCacheFolder = File(getChapterCachePath(mangaId, chapterId))
-        if (outputFile.exists()) handleExistingCbzFile(outputFile, chapterFolder)
+        if (outputFile.exists()) handleExistingCbzFile(outputFile, chapterCacheFolder)
 
-        FolderProvider(mangaId, chapterId).download().execute(download, scope, step)
+        super.downloadImpl(download, scope, step)
 
         withContext(Dispatchers.IO) {
             outputFile.createNewFile()
         }
 
         ZipArchiveOutputStream(outputFile.outputStream()).use { zipOut ->
-            if (chapterFolder.isDirectory) {
+            if (chapterCacheFolder.isDirectory) {
-                chapterFolder.listFiles()?.sortedBy { it.name }?.forEach {
+                chapterCacheFolder.listFiles()?.sortedBy { it.name }?.forEach {
                     val entry = ZipArchiveEntry(it.name)
                     try {
                         zipOut.putArchiveEntry(entry)
@@ -56,8 +55,8 @@ class ArchiveProvider(mangaId: Int, chapterId: Int) : ChaptersFilesProvider(mang
             }
         }
 
-        if (chapterFolder.exists() && chapterFolder.isDirectory) {
+        if (chapterCacheFolder.exists() && chapterCacheFolder.isDirectory) {
-            chapterFolder.deleteRecursively()
+            chapterCacheFolder.deleteRecursively()
         }
 
         return true

server/src/main/kotlin/suwayomi/tachidesk/manga/impl/download/fileProvider/impl/FolderProvider.kt

@@ -1,18 +1,10 @@
 package suwayomi.tachidesk.manga.impl.download.fileProvider.impl
 
 import kotlinx.coroutines.CoroutineScope
-import kotlinx.coroutines.FlowPreview
-import kotlinx.coroutines.Job
-import kotlinx.coroutines.flow.distinctUntilChanged
-import kotlinx.coroutines.flow.launchIn
-import kotlinx.coroutines.flow.onEach
-import kotlinx.coroutines.flow.sample
-import suwayomi.tachidesk.manga.impl.Page
-import suwayomi.tachidesk.manga.impl.Page.getPageName
 import suwayomi.tachidesk.manga.impl.download.fileProvider.ChaptersFilesProvider
 import suwayomi.tachidesk.manga.impl.download.model.DownloadChapter
+import suwayomi.tachidesk.manga.impl.util.getChapterCachePath
 import suwayomi.tachidesk.manga.impl.util.getChapterDownloadPath
-import suwayomi.tachidesk.manga.impl.util.storage.ImageResponse
 import java.io.File
 import java.io.FileInputStream
 import java.io.InputStream
@@ -30,47 +22,28 @@ class FolderProvider(mangaId: Int, chapterId: Int) : ChaptersFilesProvider(manga
         return Pair(FileInputStream(file).buffered(), "image/$fileType")
     }
 
-    @OptIn(FlowPreview::class)
     override suspend fun downloadImpl(
         download: DownloadChapter,
         scope: CoroutineScope,
         step: suspend (DownloadChapter?, Boolean) -> Unit
     ): Boolean {
-        val pageCount = download.chapter.pageCount
         val chapterDir = getChapterDownloadPath(mangaId, chapterId)
         val folder = File(chapterDir)
-        folder.mkdirs()
 
-        for (pageNum in 0 until pageCount) {
+        val alreadyDownloaded = folder.exists()
-            var pageProgressJob: Job? = null
+        if (alreadyDownloaded) {
-            val fileName = getPageName(pageNum) // might have to change this to index stored in database
+            return true
-            if (isExistingFile(folder, fileName)) continue
-            try {
-                Page.getPageImage(
-                    mangaId = download.mangaId,
-                    chapterIndex = download.chapterIndex,
-                    index = pageNum
-                ) { flow ->
-                    pageProgressJob = flow
-                        .sample(100)
-                        .distinctUntilChanged()
-                        .onEach {
-                            download.progress = (pageNum.toFloat() + (it.toFloat() * 0.01f)) / pageCount
-                            step(null, false) // don't throw on canceled download here since we can't do anything
-                        }
-                        .launchIn(scope)
-                }.first.use { image ->
-                    val filePath = "$chapterDir/$fileName"
-                    ImageResponse.saveImage(filePath, image)
-                }
-            } finally {
-                // always cancel the page progress job even if it throws an exception to avoid memory leaks
-                pageProgressJob?.cancel()
-            }
-            // TODO: retry on error with 2,4,8 seconds of wait
-            download.progress = ((pageNum + 1).toFloat()) / pageCount
-            step(download, false)
         }
+
+        val downloadSucceeded = super.downloadImpl(download, scope, step)
+        if (!downloadSucceeded) {
+            return false
+        }
+
+        folder.mkdirs()
+        val cacheChapterDir = getChapterCachePath(mangaId, chapterId)
+        File(cacheChapterDir).renameTo(folder)
+
         return true
     }