Resolve issue where read chapters were still being downloaded during …

…manual manga fetch

app/src/main/java/eu/kanade/tachiyomi/data/library/LibraryUpdateJob.kt

@@ -39,6 +39,7 @@ import kotlinx.coroutines.ensureActive
 import kotlinx.coroutines.sync.Semaphore
 import kotlinx.coroutines.sync.withPermit
 import logcat.LogPriority
+import mihon.core.chapters.utils.filterChaptersToDownload
 import mihon.domain.chapter.interactor.GetReadChapterCountByMangaIdAndChapterNumber
 import tachiyomi.core.common.i18n.stringResource
 import tachiyomi.core.common.preference.getAndSet
@@ -330,14 +331,10 @@ class LibraryUpdateJob(private val context: Context, workerParams: WorkerParamet
         hasDownloads: AtomicBoolean
     ) {
         val categoryIds = getCategories.await(manga.id).map { it.id }
-        val onlyDownloadUnreadChapters = downloadPreferences.downloadUnreadChaptersOnly().get()
 
         if (manga.shouldDownloadNewChapters(categoryIds, downloadPreferences)) {
-            val chaptersToDownload = if (onlyDownloadUnreadChapters) {
-                newChapters.filter { getReadChapterCount.await(manga.id, it.chapterNumber) == 0L }
-            } else {
-                newChapters
-            }
+            val chaptersToDownload = newChapters
+                .filterChaptersToDownload(manga, getReadChapterCount, downloadPreferences)
 
             if (chaptersToDownload.isNotEmpty()) {
                 downloadChapters(manga, chaptersToDownload)

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

@@ -48,6 +48,8 @@ import kotlinx.coroutines.flow.update
 import kotlinx.coroutines.isActive
 import kotlinx.coroutines.launch
 import logcat.LogPriority
+import mihon.core.chapters.utils.filterChaptersToDownload
+import mihon.domain.chapter.interactor.GetReadChapterCountByMangaIdAndChapterNumber
 import tachiyomi.core.common.i18n.stringResource
 import tachiyomi.core.common.preference.CheckboxState
 import tachiyomi.core.common.preference.TriState
@@ -109,6 +111,7 @@ class MangaScreenModel(
     private val addTracks: AddTracks = Injekt.get(),
     private val setMangaCategories: SetMangaCategories = Injekt.get(),
     private val mangaRepository: MangaRepository = Injekt.get(),
+    private val getReadChapterCount: GetReadChapterCountByMangaIdAndChapterNumber = Injekt.get(),
     val snackbarHostState: SnackbarHostState = SnackbarHostState(),
 ) : StateScreenModel<MangaScreenModel.State>(State.Loading) {
 
@@ -779,7 +782,8 @@ class MangaScreenModel(
                 return@launchNonCancellable
             }
 
-            downloadChapters(chapters)
+            val chaptersToDownload = chapters.filterChaptersToDownload(manga, getReadChapterCount, downloadPreferences)
+            downloadChapters(chaptersToDownload)
         }
     }
 

app/src/main/java/mihon/core/chapters/utils/FilterChaptersToDownload.kt

@@ -0,0 +1,33 @@
+package mihon.core.chapters.utils
+
+import mihon.domain.chapter.interactor.GetReadChapterCountByMangaIdAndChapterNumber
+import tachiyomi.domain.chapter.model.Chapter
+import tachiyomi.domain.download.service.DownloadPreferences
+import tachiyomi.domain.manga.model.Manga
+
+/**
+ * Filters the list of chapters based on the user's download preferences.
+ *
+ * This function checks the user's preference for downloading only unread chapters. If the
+ * preference is enabled, it filters the chapters to include only those that haven't been read.
+ * Otherwise, it returns the original list of chapters.
+ *
+ * @param manga The manga to which the chapters belong.
+ * @param getReadChapterCount A function to get the count of times a chapter has been read.
+ * @param downloadPreferences User preferences related to downloading chapters.
+ * @return A list of chapters filtered according to the download preferences. If the user prefers to download only
+ * unread chapters, the list will contain only unread chapters. Otherwise, it will return the original list of chapters.
+ */
+suspend fun List<Chapter>.filterChaptersToDownload(
+    manga: Manga,
+    getReadChapterCount: GetReadChapterCountByMangaIdAndChapterNumber,
+    downloadPreferences: DownloadPreferences,
+): List<Chapter> {
+    val onlyDownloadUnreadChapters = downloadPreferences.downloadUnreadChaptersOnly().get()
+
+    return if (onlyDownloadUnreadChapters) {
+        this.filter { getReadChapterCount.await(manga.id, it.chapterNumber) == 0L }
+    } else {
+        this
+    }
+}