Fixed formatting of downloader

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

@@ -85,7 +85,8 @@ class Downloader(
     /**
      * Whether the downloader is running.
      */
-    @Volatile private var isRunning: Boolean = false
+    @Volatile
+    private var isRunning: Boolean = false
 
     init {
         launchNow {
@@ -102,11 +103,9 @@ class Downloader(
      * @return true if the downloader is started, false otherwise.
      */
     fun start(): Boolean {
-        if (isRunning || queue.isEmpty())
+        if (isRunning || queue.isEmpty()) return false
-            return false
         notifier.paused = false
-        if (!subscriptions.hasSubscriptions())
+        if (!subscriptions.hasSubscriptions()) initializeSubscriptions()
-            initializeSubscriptions()
 
         val pending = queue.filter { it.status != Download.DOWNLOADED }
         pending.forEach { if (it.status != Download.QUEUE) it.status = Download.QUEUE }
@@ -120,9 +119,7 @@ class Downloader(
      */
     fun stop(reason: String? = null) {
         destroySubscriptions()
-        queue
+        queue.filter { it.status == Download.DOWNLOADING }.forEach { it.status = Download.ERROR }
-                .filter { it.status == Download.DOWNLOADING }
-                .forEach { it.status = Download.ERROR }
 
         if (reason != null) {
             notifier.onWarning(reason)
@@ -145,9 +142,7 @@ class Downloader(
      */
     fun pause() {
         destroySubscriptions()
-        queue
+        queue.filter { it.status == Download.DOWNLOADING }.forEach { it.status = Download.QUEUE }
-                .filter { it.status == Download.DOWNLOADING }
-                .forEach { it.status = Download.QUEUE }
         notifier.paused = true
     }
 
@@ -166,8 +161,7 @@ class Downloader(
 
         // Needed to update the chapter view
         if (isNotification) {
-            queue
+            queue.filter { it.status == Download.QUEUE }
-                    .filter { it.status == Download.QUEUE }
                 .forEach { it.status = Download.NOT_DOWNLOADED }
         }
         queue.clear()
@@ -182,8 +176,7 @@ class Downloader(
     fun clearQueue(manga: Manga, isNotification: Boolean = false) {
         // Needed to update the chapter view
         if (isNotification) {
-            queue
+            queue.filter { it.status == Download.QUEUE && it.manga.id == manga.id }
-                .filter { it.status == Download.QUEUE && it.manga.id == manga.id }
                 .forEach { it.status = Download.NOT_DOWNLOADED }
         }
         queue.remove(manga)
@@ -204,10 +197,9 @@ class Downloader(
         subscriptions.clear()
 
         subscriptions += downloadsRelay.concatMapIterable { it }
-                .concatMap { downloadChapter(it).subscribeOn(Schedulers.io()) }
+            .concatMap { downloadChapter(it).subscribeOn(Schedulers.io()) }.onBackpressureBuffer()
-                .onBackpressureBuffer()
+            .observeOn(AndroidSchedulers.mainThread()).subscribe({
-                .observeOn(AndroidSchedulers.mainThread())
+                completeDownload(it)
-                .subscribe({ completeDownload(it)
             }, { error ->
                 DownloadService.stop(context)
                 Timber.e(error)
@@ -233,8 +225,7 @@ class Downloader(
      * @param chapters the list of chapters to download.
      * @param autoStart whether to start the downloader after enqueing the chapters.
      */
-    fun queueChapters(manga: Manga, chapters: List<Chapter>, autoStart: Boolean) =
+    fun queueChapters(manga: Manga, chapters: List<Chapter>, autoStart: Boolean) = launchUI {
-        launchUI {
         val source = sourceManager.get(manga.source) as? HttpSource ?: return@launchUI
         val wasEmpty = queue.isEmpty()
         // Called in background thread, the operation can be slow with SAF.
@@ -282,8 +273,7 @@ class Downloader(
 
         val pageListObservable = if (download.pages == null) {
             // Pull page list from network and add them to download object
-            download.source.fetchPageList(download.chapter)
+            download.source.fetchPageList(download.chapter).doOnNext { pages ->
-                    .doOnNext { pages ->
                     if (pages.isEmpty()) {
                         throw Exception("Page list is empty")
                     }
@@ -294,12 +284,9 @@ class Downloader(
             Observable.just(download.pages!!)
         }
 
-        pageListObservable
+        pageListObservable.doOnNext { _ ->
-                .doOnNext { _ ->
                 // Delete all temporary (unfinished) files
-                    tmpDir.listFiles()
+                tmpDir.listFiles()?.filter { it.name!!.endsWith(".tmp") }?.forEach { it.delete() }
-                            ?.filter { it.name!!.endsWith(".tmp") }
-                            ?.forEach { it.delete() }
 
                 download.downloadedImages = 0
                 download.status = Download.DOWNLOADING
@@ -309,9 +296,7 @@ class Downloader(
             // Start downloading images, consider we can have downloaded images already
             .concatMap { page -> getOrDownloadImage(page, download, tmpDir) }
             // Do when page is downloaded.
-                .doOnNext { notifier.onProgressChange(download) }
+            .doOnNext { notifier.onProgressChange(download) }.toList().map { _ -> download }
-                .toList()
-                .map { _ -> download }
             // Do after download completes
             .doOnNext { ensureSuccessfulDownload(download, mangaDir, tmpDir, chapterDirname) }
             // If the page list threw, it will resume here
@@ -330,10 +315,13 @@ class Downloader(
      * @param download the download of the page.
      * @param tmpDir the temporary directory of the download.
      */
-    private fun getOrDownloadImage(page: Page, download: Download, tmpDir: UniFile): Observable<Page> {
+    private fun getOrDownloadImage(
+        page: Page,
+        download: Download,
+        tmpDir: UniFile
+    ): Observable<Page> {
         // If the image URL is empty, do nothing
-        if (page.imageUrl == null)
+        if (page.imageUrl == null) return Observable.just(page)
-            return Observable.just(page)
 
         val filename = String.format("%03d", page.number)
         val tmpFile = tmpDir.findFile("$filename.tmp")
@@ -347,8 +335,12 @@ class Downloader(
         // If the image is already downloaded, do nothing. Otherwise download from network
         val pageObservable = when {
             imageFile != null -> Observable.just(imageFile)
-            cache.isImageInCache(page.imageUrl!!) ->
+            cache.isImageInCache(page.imageUrl!!) -> moveFromCache(
-                moveFromCache(page, cache.getImageFile(page.imageUrl!!), tmpDir, filename)
+                page,
+                cache.getImageFile(page.imageUrl!!),
+                tmpDir,
+                filename
+            )
             else -> downloadImage(page, download.source, tmpDir, filename)
         }
 
@@ -359,8 +351,7 @@ class Downloader(
                 page.progress = 100
                 download.downloadedImages++
                 page.status = Page.READY
-                }
+            }.map { page }
-                .map { page }
             // Mark this page as error and allow to download the remaining
             .onErrorReturn {
                 page.progress = 0
@@ -377,8 +368,12 @@ class Downloader(
      * @param tmpDir the temporary directory of the download.
      * @param filename the filename of the image.
      */
-    private fun moveFromCache(page: Page, file: File, tmpDir: UniFile, filename: String):
+    private fun moveFromCache(
-        Observable<UniFile> {
+        page: Page,
+        file: File,
+        tmpDir: UniFile,
+        filename: String
+    ): Observable<UniFile> {
         return Observable.just(file).map {
             val tmpFile = tmpDir.createFile("$filename.tmp")
             val inputStream = file.inputStream()
@@ -402,11 +397,15 @@ class Downloader(
      * @param tmpDir the temporary directory of the download.
      * @param filename the filename of the image.
      */
-    private fun downloadImage(page: Page, source: HttpSource, tmpDir: UniFile, filename: String): Observable<UniFile> {
+    private fun downloadImage(
+        page: Page,
+        source: HttpSource,
+        tmpDir: UniFile,
+        filename: String
+    ): Observable<UniFile> {
         page.status = Page.DOWNLOAD_IMAGE
         page.progress = 0
-        return source.fetchImage(page)
+        return source.fetchImage(page).map { response ->
-                .map { response ->
             val file = tmpDir.createFile("$filename.tmp")
             try {
                 response.body!!.source().saveTo(file.openOutputStream())
@@ -450,10 +449,7 @@ class Downloader(
      * @param dirname the real (non temporary) directory name of the download.
      */
     private fun ensureSuccessfulDownload(
-        download: Download,
+        download: Download, mangaDir: UniFile, tmpDir: UniFile, dirname: String
-        mangaDir: UniFile,
-        tmpDir: UniFile,
-        dirname: String
     ) {
 
         // Ensure that the chapter folder has all the images.