Implement a download cache

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

@@ -0,0 +1,253 @@
+package eu.kanade.tachiyomi.data.download
+
+import android.content.Context
+import android.net.Uri
+import com.hippo.unifile.UniFile
+import eu.kanade.tachiyomi.data.database.models.Chapter
+import eu.kanade.tachiyomi.data.database.models.Manga
+import eu.kanade.tachiyomi.data.preference.PreferencesHelper
+import eu.kanade.tachiyomi.data.preference.getOrDefault
+import eu.kanade.tachiyomi.source.SourceManager
+import uy.kohesive.injekt.Injekt
+import uy.kohesive.injekt.api.get
+import java.util.concurrent.TimeUnit
+
+/**
+ * Cache where we dump the downloads directory from the filesystem. This class is needed because
+ * directory checking is expensive and it slowdowns the app. The cache is invalidated by the time
+ * defined in [renewInterval] as we don't have any control over the filesystem and the user can
+ * delete the folders at any time without the app noticing.
+ *
+ * @param context the application context.
+ * @param provider the downloads directories provider.
+ * @param sourceManager the source manager.
+ * @param preferences the preferences of the app.
+ */
+class DownloadCache(private val context: Context,
+                    private val provider: DownloadProvider,
+                    private val sourceManager: SourceManager = Injekt.get(),
+                    preferences: PreferencesHelper = Injekt.get()) {
+
+    /**
+     * The interval after which this cache should be invalidated. 1 hour shouldn't cause major
+     * issues, as the cache is only used for UI feedback.
+     */
+    private val renewInterval = TimeUnit.HOURS.toMillis(1)
+
+    /**
+     * The last time the cache was refreshed.
+     */
+    private var lastRenew = 0L
+
+    /**
+     * The root directory for downloads.
+     */
+    private var rootDir = setRootDir(preferences.downloadsDirectory().getOrDefault())
+
+    init {
+        setRootDir(preferences.downloadsDirectory().getOrDefault())
+        preferences.downloadsDirectory().asObservable()
+                .skip(1)
+                .subscribe { setRootDir(it) }
+    }
+
+    /**
+     * Sets the root downloads directory and invalidates the cache.
+     *
+     * @param directory the downloads directory in [Uri] format.
+     */
+    private fun setRootDir(directory: String): RootDirectory {
+        rootDir = RootDirectory(UniFile.fromUri(context, Uri.parse(directory)))
+        lastRenew = 0L
+        return rootDir
+    }
+
+    /**
+     * Returns true if the chapter is downloaded.
+     *
+     * @param chapter the chapter to check.
+     * @param manga the manga of the chapter.
+     * @param skipCache whether to skip the directory cache and check in the filesystem.
+     */
+    fun isChapterDownloaded(chapter: Chapter, manga: Manga, skipCache: Boolean): Boolean {
+        if (skipCache) {
+            val source = sourceManager.get(manga.source) ?: return false
+            return provider.findChapterDir(chapter, manga, source) != null
+        }
+
+        checkRenew()
+
+        val sourceDir = rootDir.files[manga.source]
+        if (sourceDir != null) {
+            val mangaDir = sourceDir.files[provider.getMangaDirName(manga)]
+            if (mangaDir != null) {
+                return provider.getChapterDirName(chapter) in mangaDir.files
+            }
+        }
+        return false
+    }
+
+    /**
+     * Returns the amount of downloaded chapters for a manga.
+     *
+     * @param manga the manga to check.
+     */
+    fun getDownloadCount(manga: Manga): Int {
+        checkRenew()
+
+        val sourceDir = rootDir.files[manga.source]
+        if (sourceDir != null) {
+            val mangaDir = sourceDir.files[provider.getMangaDirName(manga)]
+            if (mangaDir != null) {
+                return mangaDir.files.size
+            }
+        }
+        return 0
+    }
+
+    /**
+     * Checks if the cache needs a renewal and performs it if needed.
+     */
+    @Synchronized
+    private fun checkRenew() {
+        if (lastRenew + renewInterval < System.currentTimeMillis()) {
+            renew()
+            lastRenew = System.currentTimeMillis()
+        }
+    }
+
+    /**
+     * Renews the downloads cache.
+     */
+    private fun renew() {
+        val onlineSources = sourceManager.getOnlineSources()
+
+        val sourceDirs = rootDir.dir.listFiles()
+                .orEmpty()
+                .associate { it.name to SourceDirectory(it) }
+                .mapNotNullKeys { entry ->
+                    onlineSources.find { provider.getSourceDirName(it) == entry.key }?.id
+                }
+
+        rootDir.files = sourceDirs
+
+        sourceDirs.values.forEach { sourceDir ->
+            val mangaDirs = sourceDir.dir.listFiles()
+                    .orEmpty()
+                    .associateNotNullKeys { it.name to MangaDirectory(it) }
+
+            sourceDir.files = mangaDirs
+
+            mangaDirs.values.forEach { mangaDir ->
+                val chapterDirs = mangaDir.dir.listFiles()
+                        .orEmpty()
+                        .mapNotNull { it.name }
+                        .toHashSet()
+
+                mangaDir.files = chapterDirs
+            }
+        }
+    }
+
+    /**
+     * Adds a chapter that has just been download to this cache.
+     *
+     * @param chapterDirName the downloaded chapter's directory name.
+     * @param mangaUniFile the directory of the manga.
+     * @param manga the manga of the chapter.
+     */
+    @Synchronized
+    fun addChapter(chapterDirName: String, mangaUniFile: UniFile, manga: Manga) {
+        // Retrieve the cached source directory or cache a new one
+        var sourceDir = rootDir.files[manga.source]
+        if (sourceDir == null) {
+            val source = sourceManager.get(manga.source) ?: return
+            val sourceUniFile = provider.findSourceDir(source) ?: return
+            sourceDir = SourceDirectory(sourceUniFile)
+            rootDir.files += manga.source to sourceDir
+        }
+
+        // Retrieve the cached manga directory or cache a new one
+        val mangaDirName = provider.getMangaDirName(manga)
+        var mangaDir = sourceDir.files[mangaDirName]
+        if (mangaDir == null) {
+            mangaDir = MangaDirectory(mangaUniFile)
+            sourceDir.files += mangaDirName to mangaDir
+        }
+
+        // Save the chapter directory
+        mangaDir.files += chapterDirName
+    }
+
+    /**
+     * Removes a chapter that has been deleted from this cache.
+     *
+     * @param chapter the chapter to remove.
+     * @param manga the manga of the chapter.
+     */
+    @Synchronized
+    fun removeChapter(chapter: Chapter, manga: Manga) {
+        val sourceDir = rootDir.files[manga.source] ?: return
+        val mangaDir = sourceDir.files[provider.getMangaDirName(manga)] ?: return
+        val chapterDirName = provider.getChapterDirName(chapter)
+        if (chapterDirName in mangaDir.files) {
+            mangaDir.files -= chapterDirName
+        }
+    }
+
+    /**
+     * Removes a manga that has been deleted from this cache.
+     *
+     * @param manga the manga to remove.
+     */
+    @Synchronized
+    fun removeManga(manga: Manga) {
+        val sourceDir = rootDir.files[manga.source] ?: return
+        val mangaDirName = provider.getMangaDirName(manga)
+        if (mangaDirName in sourceDir.files) {
+            sourceDir.files -= mangaDirName
+        }
+    }
+
+    /**
+     * Class to store the files under the root downloads directory.
+     */
+    private class RootDirectory(val dir: UniFile,
+                                var files: Map<Long, SourceDirectory> = hashMapOf())
+
+    /**
+     * Class to store the files under a source directory.
+     */
+    private class SourceDirectory(val dir: UniFile,
+                                  var files: Map<String, MangaDirectory> = hashMapOf())
+
+    /**
+     * Class to store the files under a manga directory.
+     */
+    private class MangaDirectory(val dir: UniFile,
+                                 var files: Set<String> = hashSetOf())
+
+    /**
+     * Returns a new map containing only the key entries of [transform] that are not null.
+     */
+    private inline fun <K, V, R> Map<out K, V>.mapNotNullKeys(transform: (Map.Entry<K?, V>) -> R?): Map<R, V> {
+        val destination = LinkedHashMap<R, V>()
+        forEach { element -> transform(element)?.let { destination.put(it, element.value) } }
+        return destination
+    }
+
+    /**
+     * Returns a map from a list containing only the key entries of [transform] that are not null.
+     */
+    private inline fun <T, K, V> Array<T>.associateNotNullKeys(transform: (T) -> Pair<K?, V>): Map<K, V> {
+        val destination = LinkedHashMap<K, V>()
+        for (element in this) {
+            val (key, value) = transform(element)
+            if (key != null) {
+                destination.put(key, value)
+            }
+        }
+        return destination
+    }
+
+}

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

@@ -24,10 +24,15 @@ class DownloadManager(context: Context) {
      */
     private val provider = DownloadProvider(context)
 
+    /**
+     * Cache of downloaded chapters.
+     */
+    private val cache = DownloadCache(context, provider)
+
     /**
      * Downloader whose only task is to download chapters.
      */
-    private val downloader = Downloader(context, provider)
+    private val downloader = Downloader(context, provider, cache)
 
     /**
      * Downloads queue, where the pending chapters are stored.
@@ -94,7 +99,7 @@ class DownloadManager(context: Context) {
      * @return an observable containing the list of pages from the chapter.
      */
     fun buildPageList(source: Source, manga: Manga, chapter: Chapter): Observable<List<Page>> {
-        return buildPageList(provider.findChapterDir(source, manga, chapter))
+        return buildPageList(provider.findChapterDir(chapter, manga, source))
     }
 
     /**
@@ -120,61 +125,45 @@ class DownloadManager(context: Context) {
     }
 
     /**
-     * Returns the directory name for a manga.
+     * Returns true if the chapter is downloaded.
      *
-     * @param manga the manga to query.
+     * @param chapter the chapter to check.
-     */
-    fun getMangaDirName(manga: Manga): String {
-        return provider.getMangaDirName(manga)
-    }
-
-    /**
-     * Returns the directory name for the given chapter.
-     *
-     * @param chapter the chapter to query.
-     */
-    fun getChapterDirName(chapter: Chapter): String {
-        return provider.getChapterDirName(chapter)
-    }
-
-    /**
-     * Returns the download directory for a source if it exists.
-     *
-     * @param source the source to query.
-     */
-    fun findSourceDir(source: Source): UniFile? {
-        return provider.findSourceDir(source)
-    }
-
-    /**
-     * Returns the directory for the given manga, if it exists.
-     *
-     * @param source the source of the manga.
-     * @param manga the manga to query.
-     */
-    fun findMangaDir(source: Source, manga: Manga): UniFile? {
-        return provider.findMangaDir(source, manga)
-    }
-
-    /**
-     * Returns the directory for the given chapter, if it exists.
-     *
-     * @param source the source of the chapter.
      * @param manga the manga of the chapter.
-     * @param chapter the chapter to query.
+     * @param skipCache whether to skip the directory cache and check in the filesystem.
      */
-    fun findChapterDir(source: Source, manga: Manga, chapter: Chapter): UniFile? {
+    fun isChapterDownloaded(chapter: Chapter, manga: Manga, skipCache: Boolean = false): Boolean {
-        return provider.findChapterDir(source, manga, chapter)
+        return cache.isChapterDownloaded(chapter, manga, skipCache)
+    }
+
+    /**
+     * Returns the amount of downloaded chapters for a manga.
+     *
+     * @param manga the manga to check.
+     */
+    fun getDownloadCount(manga: Manga): Int {
+        return cache.getDownloadCount(manga)
     }
 
     /**
      * Deletes the directory of a downloaded chapter.
      *
-     * @param source the source of the chapter.
-     * @param manga the manga of the chapter.
      * @param chapter the chapter to delete.
+     * @param manga the manga of the chapter.
+     * @param source the source of the chapter.
      */
-    fun deleteChapter(source: Source, manga: Manga, chapter: Chapter) {
+    fun deleteChapter(chapter: Chapter, manga: Manga, source: Source) {
-        provider.findChapterDir(source, manga, chapter)?.delete()
+        provider.findChapterDir(chapter, manga, source)?.delete()
+        cache.removeChapter(chapter, manga)
+    }
+
+    /**
+     * Deletes the directory of a downloaded manga.
+     *
+     * @param manga the manga to delete.
+     * @param source the source of the manga.
+     */
+    fun deleteManga(manga: Manga, source: Source) {
+        provider.findMangaDir(manga, source)?.delete()
+        cache.removeManga(manga)
     }
 }

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

@@ -40,10 +40,10 @@ class DownloadProvider(private val context: Context) {
     /**
      * Returns the download directory for a manga. For internal use only.
      *
-     * @param source the source of the manga.
      * @param manga the manga to query.
+     * @param source the source of the manga.
      */
-    internal fun getMangaDir(source: Source, manga: Manga): UniFile {
+    internal fun getMangaDir(manga: Manga, source: Source): UniFile {
         return downloadsDir
                 .createDirectory(getSourceDirName(source))
                 .createDirectory(getMangaDirName(manga))
@@ -61,10 +61,10 @@ class DownloadProvider(private val context: Context) {
     /**
      * Returns the download directory for a manga if it exists.
      *
-     * @param source the source of the manga.
      * @param manga the manga to query.
+     * @param source the source of the manga.
      */
-    fun findMangaDir(source: Source, manga: Manga): UniFile? {
+    fun findMangaDir(manga: Manga, source: Source): UniFile? {
         val sourceDir = findSourceDir(source)
         return sourceDir?.findFile(getMangaDirName(manga))
     }
@@ -72,12 +72,12 @@ class DownloadProvider(private val context: Context) {
     /**
      * Returns the download directory for a chapter if it exists.
      *
-     * @param source the source of the chapter.
-     * @param manga the manga of the chapter.
      * @param chapter the chapter to query.
+     * @param manga the manga of the chapter.
+     * @param source the source of the chapter.
      */
-    fun findChapterDir(source: Source, manga: Manga, chapter: Chapter): UniFile? {
+    fun findChapterDir(chapter: Chapter, manga: Manga, source: Source): UniFile? {
-        val mangaDir = findMangaDir(source, manga)
+        val mangaDir = findMangaDir(manga, source)
         return mangaDir?.findFile(getChapterDirName(chapter))
     }
 

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

@@ -37,8 +37,11 @@ import uy.kohesive.injekt.injectLazy
  *
  * @param context the application context.
  * @param provider the downloads directory provider.
+ * @param cache the downloads cache, used to add the downloads to the cache after their completion.
  */
-class Downloader(private val context: Context, private val provider: DownloadProvider) {
+class Downloader(private val context: Context,
+                 private val provider: DownloadProvider,
+                 private val cache: DownloadCache) {
 
     /**
      * Store for persisting downloads across restarts.
@@ -222,7 +225,7 @@ class Downloader(private val context: Context, private val provider: DownloadPro
 
         // Called in background thread, the operation can be slow with SAF.
         val chaptersWithoutDir = async {
-            val mangaDir = provider.findMangaDir(source, manga)
+            val mangaDir = provider.findMangaDir(manga, source)
 
             chapters
                     // Avoid downloading chapters with the same name.
@@ -269,7 +272,7 @@ class Downloader(private val context: Context, private val provider: DownloadPro
      */
     private fun downloadChapter(download: Download): Observable<Download> {
         val chapterDirname = provider.getChapterDirName(download.chapter)
-        val mangaDir = provider.getMangaDir(download.source, download.manga)
+        val mangaDir = provider.getMangaDir(download.manga, download.source)
         val tmpDir = mangaDir.createDirectory("${chapterDirname}_tmp")
 
         val pageListObservable = if (download.pages == null) {
@@ -305,7 +308,7 @@ class Downloader(private val context: Context, private val provider: DownloadPro
                 .toList()
                 .map { _ -> download }
                 // Do after download completes
-                .doOnNext { ensureSuccessfulDownload(download, tmpDir, chapterDirname) }
+                .doOnNext { ensureSuccessfulDownload(download, mangaDir, tmpDir, chapterDirname) }
                 // If the page list threw, it will resume here
                 .onErrorReturn { error ->
                     download.status = Download.ERROR
@@ -411,10 +414,13 @@ class Downloader(private val context: Context, private val provider: DownloadPro
      * Checks if the download was successful.
      *
      * @param download the download to check.
+     * @param mangaDir the manga directory of the download.
      * @param tmpDir the directory where the download is currently stored.
      * @param dirname the real (non temporary) directory name of the download.
      */
-    private fun ensureSuccessfulDownload(download: Download, tmpDir: UniFile, dirname: String) {
+    private fun ensureSuccessfulDownload(download: Download, mangaDir: UniFile,
+                                         tmpDir: UniFile, dirname: String) {
+
         // Ensure that the chapter folder has all the images.
         val downloadedImages = tmpDir.listFiles().orEmpty().filterNot { it.name!!.endsWith(".tmp") }
 
@@ -427,6 +433,7 @@ class Downloader(private val context: Context, private val provider: DownloadPro
         // Only rename the directory if it's downloaded.
         if (download.status == Download.DOWNLOADED) {
             tmpDir.renameTo(dirname)
+            cache.addChapter(dirname, mangaDir, download.manga)
         }
     }
 

app/src/main/java/eu/kanade/tachiyomi/ui/library/LibraryPresenter.kt

@@ -1,7 +1,6 @@
 package eu.kanade.tachiyomi.ui.library
 
 import android.os.Bundle
-import com.hippo.unifile.UniFile
 import com.jakewharton.rxrelay.BehaviorRelay
 import eu.kanade.tachiyomi.data.cache.CoverCache
 import eu.kanade.tachiyomi.data.database.DatabaseHelper
@@ -107,12 +106,6 @@ class LibraryPresenter(
      * @param map the map to filter.
      */
     private fun applyFilters(map: LibraryMap): LibraryMap {
-        // Cached list of downloaded manga directories given a source id.
-        val mangaDirsForSource = mutableMapOf<Long, Map<String?, UniFile>>()
-
-        // Cached list of downloaded chapter directories for a manga.
-        val chapterDirectories = mutableMapOf<Long, Boolean>()
-
         val filterDownloaded = preferences.filterDownloaded().getOrDefault()
 
         val filterUnread = preferences.filterUnread().getOrDefault()
@@ -121,7 +114,7 @@ class LibraryPresenter(
 
         val filterFn: (LibraryItem) -> Boolean = f@ { item ->
             // Filter out manga without source.
-            val source = sourceManager.get(item.manga.source) ?: return@f false
+            sourceManager.get(item.manga.source) ?: return@f false
 
             // Filter when there isn't unread chapters.
             if (filterUnread && item.manga.unread == 0) {
@@ -132,28 +125,14 @@ class LibraryPresenter(
                 return@f false
             }
 
-            // Filter when the download directory doesn't exist or is null.
+            // Filter when there are no downloads.
             if (filterDownloaded) {
                 // Don't bother with directory checking if download count has been set.
                 if (item.downloadCount != -1) {
                     return@f item.downloadCount > 0
                 }
 
-                // Get the directories for the source of the manga.
+                return@f downloadManager.getDownloadCount(item.manga) > 0
-                val dirsForSource = mangaDirsForSource.getOrPut(source.id) {
-                    val sourceDir = downloadManager.findSourceDir(source)
-                    sourceDir?.listFiles()?.associateBy { it.name }.orEmpty()
-                }
-
-                val mangaDirName = downloadManager.getMangaDirName(item.manga)
-                val mangaDir = dirsForSource[mangaDirName] ?: return@f false
-
-                val hasDirs = chapterDirectories.getOrPut(item.manga.id!!) {
-                    mangaDir.listFiles()?.isNotEmpty() ?: false
-                }
-                if (!hasDirs) {
-                    return@f false
-                }
             }
             true
         }
@@ -177,31 +156,9 @@ class LibraryPresenter(
             return
         }
 
-        // Cached list of downloaded manga directories given a source id.
-        val mangaDirsForSource = mutableMapOf<Long, Map<String?, UniFile>>()
-
-        // Cached list of downloaded chapter directories for a manga.
-        val chapterDirectories = mutableMapOf<Long, Int>()
-
-        val downloadCountFn: (LibraryItem) -> Int = f@ { item ->
-            val source = sourceManager.get(item.manga.source) ?: return@f 0
-
-            // Get the directories for the source of the manga.
-            val dirsForSource = mangaDirsForSource.getOrPut(source.id) {
-                val sourceDir = downloadManager.findSourceDir(source)
-                sourceDir?.listFiles()?.associateBy { it.name }.orEmpty()
-            }
-            val mangaDirName = downloadManager.getMangaDirName(item.manga)
-            val mangaDir = dirsForSource[mangaDirName] ?: return@f 0
-
-            chapterDirectories.getOrPut(item.manga.id!!) {
-                mangaDir.listFiles()?.size ?: 0
-            }
-        }
-
         for ((_, itemList) in map) {
             for (item in itemList) {
-                item.downloadCount = downloadCountFn(item)
+                item.downloadCount = downloadManager.getDownloadCount(item.manga)
             }
         }
     }
@@ -360,7 +317,7 @@ class LibraryPresenter(
                 if (deleteChapters) {
                     val source = sourceManager.get(manga.source) as? HttpSource
                     if (source != null) {
-                        downloadManager.findMangaDir(source, manga)?.delete()
+                        downloadManager.deleteManga(manga, source)
                     }
                 }
             }

app/src/main/java/eu/kanade/tachiyomi/ui/manga/chapter/ChaptersPresenter.kt

@@ -128,13 +128,11 @@ class ChaptersPresenter(
      * @param chapters the list of chapter from the database.
      */
     private fun setDownloadedChapters(chapters: List<ChapterItem>) {
-        val files = downloadManager.findMangaDir(source, manga)?.listFiles() ?: return
+        for (chapter in chapters) {
-        val cached = mutableMapOf<Chapter, String>()
+            if (downloadManager.isChapterDownloaded(chapter, manga)) {
-        files.mapNotNull { it.name }
+                chapter.status = Download.DOWNLOADED
-                .mapNotNull { name -> chapters.find {
+            }
-                    name == cached.getOrPut(it) { downloadManager.getChapterDirName(it) }
+        }
-                } }
-                .forEach { it.status = Download.DOWNLOADED }
     }
 
     /**
@@ -283,7 +281,7 @@ class ChaptersPresenter(
      */
     private fun deleteChapter(chapter: ChapterItem) {
         downloadManager.queue.remove(chapter)
-        downloadManager.deleteChapter(source, manga, chapter)
+        downloadManager.deleteChapter(chapter, manga, source)
         chapter.status = Download.NOT_DOWNLOADED
         chapter.download = null
     }

app/src/main/java/eu/kanade/tachiyomi/ui/manga/info/MangaInfoPresenter.kt

@@ -115,14 +115,14 @@ class MangaInfoPresenter(
      * Returns true if the manga has any downloads.
      */
     fun hasDownloads(): Boolean {
-        return downloadManager.findMangaDir(source, manga) != null
+        return downloadManager.getDownloadCount(manga) > 0
     }
 
     /**
      * Deletes all the downloads for the manga.
      */
     fun deleteDownloads() {
-        downloadManager.findMangaDir(source, manga)?.delete()
+        downloadManager.deleteManga(manga, source)
     }
 
     /**

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

@@ -79,7 +79,7 @@ class ChapterLoader(
     private fun retrievePageList(chapter: ReaderChapter) = Observable.just(chapter)
             .flatMap {
                 // Check if the chapter is downloaded.
-                chapter.isDownloaded = downloadManager.findChapterDir(source, manga, chapter) != null
+                chapter.isDownloaded = downloadManager.isChapterDownloaded(chapter, manga, true)
 
                 if (chapter.isDownloaded) {
                     // Fetch the page list from disk.

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

@@ -411,7 +411,7 @@ class ReaderPresenter(
     fun deleteChapter(chapter: ReaderChapter, manga: Manga) {
         chapter.isDownloaded = false
         chapter.pages?.forEach { it.status == Page.QUEUE }
-        downloadManager.deleteChapter(source, manga, chapter)
+        downloadManager.deleteChapter(chapter, manga, source)
     }
 
     /**

app/src/main/java/eu/kanade/tachiyomi/ui/recent_updates/RecentChaptersPresenter.kt

@@ -1,7 +1,6 @@
 package eu.kanade.tachiyomi.ui.recent_updates
 
 import android.os.Bundle
-import com.hippo.unifile.UniFile
 import eu.kanade.tachiyomi.data.database.DatabaseHelper
 import eu.kanade.tachiyomi.data.database.models.MangaChapter
 import eu.kanade.tachiyomi.data.download.DownloadManager
@@ -114,36 +113,11 @@ class RecentChaptersPresenter(
      * @param items the list of chapter from the database.
      */
     private fun setDownloadedChapters(items: List<RecentChapterItem>) {
-        // Cached list of downloaded manga directories. Directory name is also cached because
-        // it's slow when using SAF.
-        val mangaDirsForSource = mutableMapOf<Long, Map<String?, UniFile>>()
-
-        // Cached list of downloaded chapter directories for a manga.
-        val chapterDirsForManga = mutableMapOf<Long, Map<String?, UniFile>>()
-
         for (item in items) {
             val manga = item.manga
             val chapter = item.chapter
-            val source = sourceManager.get(manga.source) ?: continue
 
-            // Get the directories for the source of the manga.
+            if (downloadManager.isChapterDownloaded(chapter, manga)) {
-            val dirsForSource = mangaDirsForSource.getOrPut(source.id) {
-                val sourceDir = downloadManager.findSourceDir(source)
-                sourceDir?.listFiles()?.associateBy { it.name }.orEmpty()
-            }
-
-            // Get the manga directory in the source or continue.
-            val mangaDirName = downloadManager.getMangaDirName(manga)
-            val mangaDir = dirsForSource[mangaDirName] ?: continue
-
-            // Get the directories for the manga.
-            val chapterDirs = chapterDirsForManga.getOrPut(manga.id!!) {
-                mangaDir.listFiles()?.associateBy { it.name }.orEmpty()
-            }
-
-            // Assign the download if the directory exists.
-            val chapterDirName = downloadManager.getChapterDirName(chapter)
-            if (chapterDirName in chapterDirs) {
                 item.status = Download.DOWNLOADED
             }
         }
@@ -216,7 +190,7 @@ class RecentChaptersPresenter(
     private fun deleteChapter(item: RecentChapterItem) {
         val source = sourceManager.get(item.manga.source) ?: return
         downloadManager.queue.remove(item.chapter)
-        downloadManager.deleteChapter(source, item.manga, item.chapter)
+        downloadManager.deleteChapter(item.chapter, item.manga, source)
         item.status = Download.NOT_DOWNLOADED
         item.download = null
     }