Resume download on network becomes available

app/src/main/java/org/koitharu/kotatsu/download/domain/DownloadState2.kt

@@ -10,6 +10,7 @@ data class DownloadState2(
 	val manga: Manga,
 	val isIndeterminate: Boolean,
 	val isPaused: Boolean = false,
+	val isStopped: Boolean = false,
 	val error: String? = null,
 	val totalChapters: Int = 0,
 	val currentChapter: Int = 0,
@@ -17,6 +18,7 @@ data class DownloadState2(
 	val currentPage: Int = 0,
 	val eta: Long = -1L,
 	val localManga: LocalManga? = null,
+	val downloadedChapters: LongArray = LongArray(0),
 	val timestamp: Long = System.currentTimeMillis(),
 ) {
 
@@ -30,7 +32,7 @@ data class DownloadState2(
 		get() = localManga != null || (error != null && !isPaused)
 
 	val isParticularProgress: Boolean
-		get() = localManga == null && error == null && !isPaused && max > 0 && !isIndeterminate
+		get() = localManga == null && error == null && !isPaused && !isStopped && max > 0 && !isIndeterminate
 
 	fun toWorkData() = Data.Builder()
 		.putLong(DATA_MANGA_ID, manga.id)
@@ -39,7 +41,7 @@ data class DownloadState2(
 		.putLong(DATA_ETA, eta)
 		.putLong(DATA_TIMESTAMP, timestamp)
 		.putString(DATA_ERROR, error)
-		.putInt(DATA_CHAPTERS, totalChapters)
+		.putLongArray(DATA_CHAPTERS, downloadedChapters)
 		.putBoolean(DATA_INDETERMINATE, isIndeterminate)
 		.putBoolean(DATA_PAUSED, isPaused)
 		.build()
@@ -72,6 +74,6 @@ data class DownloadState2(
 
 		fun getTimestamp(data: Data): Date = Date(data.getLong(DATA_TIMESTAMP, 0L))
 
-		fun getTotalChapters(data: Data): Int = data.getInt(DATA_CHAPTERS, 0)
+		fun getDownloadedChapters(data: Data): LongArray = data.getLongArray(DATA_CHAPTERS) ?: LongArray(0)
 	}
 }

app/src/main/java/org/koitharu/kotatsu/download/ui/list/DownloadsViewModel.kt

@@ -172,7 +172,7 @@ class DownloadsViewModel @Inject constructor(
 	}
 
 	private suspend fun WorkInfo.toUiModel(): DownloadItemModel? {
-		val workData = if (progress != Data.EMPTY) progress else outputData
+		val workData = if (outputData == Data.EMPTY) progress else outputData
 		val mangaId = DownloadState2.getMangaId(workData)
 		if (mangaId == 0L) return null
 		val manga = getManga(mangaId) ?: return null
@@ -187,7 +187,7 @@ class DownloadsViewModel @Inject constructor(
 			progress = DownloadState2.getProgress(workData),
 			eta = DownloadState2.getEta(workData),
 			timestamp = DownloadState2.getTimestamp(workData),
-			totalChapters = DownloadState2.getTotalChapters(workData),
+			totalChapters = DownloadState2.getDownloadedChapters(workData).size,
 		)
 	}
 

app/src/main/java/org/koitharu/kotatsu/download/ui/worker/DownloadNotificationFactory.kt

@@ -133,11 +133,29 @@ class DownloadNotificationFactory @AssistedInject constructor(
 				builder.setWhen(System.currentTimeMillis())
 			}
 
+			state.isStopped -> {
+				builder.setProgress(0, 0, false)
+				builder.setContentText(context.getString(R.string.queued))
+				builder.setCategory(NotificationCompat.CATEGORY_PROGRESS)
+				builder.setStyle(null)
+				builder.setOngoing(true)
+				builder.setSmallIcon(R.drawable.ic_stat_paused)
+				builder.addAction(actionCancel)
+			}
+
 			state.isPaused -> { // paused (with error or manually)
 				builder.setProgress(state.max, state.progress, false)
-				val percent = context.getString(R.string.percent_string_pattern, (state.percent * 100).format())
-				builder.setContentText(percent)
-				builder.setContentText(state.error)
+				val percent = if (state.percent >= 0) {
+					context.getString(R.string.percent_string_pattern, (state.percent * 100).format())
+				} else {
+					null
+				}
+				if (state.error != null) {
+					builder.setContentText(state.error)
+					builder.setSubText(percent)
+				} else {
+					builder.setContentText(percent)
+				}
 				builder.setCategory(NotificationCompat.CATEGORY_PROGRESS)
 				builder.setStyle(null)
 				builder.setOngoing(true)
@@ -161,7 +179,11 @@ class DownloadNotificationFactory @AssistedInject constructor(
 
 			else -> {
 				builder.setProgress(state.max, state.progress, false)
-				val percent = context.getString(R.string.percent_string_pattern, (state.percent * 100).format())
+				val percent = if (state.percent >= 0f) {
+					context.getString(R.string.percent_string_pattern, (state.percent * 100).format())
+				} else {
+					null
+				}
 				if (state.eta > 0L) {
 					val eta = DateUtils.getRelativeTimeSpanString(
 						state.eta,

app/src/main/java/org/koitharu/kotatsu/download/ui/worker/DownloadWorker.kt

@@ -48,6 +48,7 @@ import org.koitharu.kotatsu.local.data.input.LocalMangaInput
 import org.koitharu.kotatsu.local.data.output.LocalMangaOutput
 import org.koitharu.kotatsu.local.domain.LocalMangaRepository
 import org.koitharu.kotatsu.parsers.model.Manga
+import org.koitharu.kotatsu.parsers.model.MangaChapter
 import org.koitharu.kotatsu.parsers.model.MangaSource
 import org.koitharu.kotatsu.parsers.util.await
 import org.koitharu.kotatsu.parsers.util.mapToSet
@@ -82,7 +83,9 @@ class DownloadWorker @AssistedInject constructor(
 	private val notificationManager = appContext.getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
 
 	@Volatile
-	private lateinit var currentState: DownloadState2
+	private var lastPublishedState: DownloadState2? = null
+	private val currentState: DownloadState2
+		get() = checkNotNull(lastPublishedState)
 
 	private val pausingHandle = PausingHandle()
 	private val timeLeftEstimator = TimeLeftEstimator()
@@ -94,30 +97,44 @@ class DownloadWorker @AssistedInject constructor(
 		val mangaId = inputData.getLong(MANGA_ID, 0L)
 		val manga = mangaDataRepository.findMangaById(mangaId) ?: return Result.failure()
 		val chaptersIds = inputData.getLongArray(CHAPTERS_IDS)?.takeUnless { it.isEmpty() }
-		currentState = DownloadState2(manga, isIndeterminate = true)
+		val downloadedIds = getDoneChapters()
+		lastPublishedState = DownloadState2(manga, isIndeterminate = true)
 		return try {
-			downloadMangaImpl(chaptersIds)
+			downloadMangaImpl(chaptersIds, downloadedIds)
 			Result.success(currentState.toWorkData())
 		} catch (e: CancellationException) {
+			withContext(NonCancellable) {
+				val notification = notificationFactory.create(currentState.copy(isStopped = true))
+				notificationManager.notify(id.hashCode(), notification)
+			}
 			throw e
 		} catch (e: IOException) {
 			e.printStackTraceDebug()
 			Result.retry()
 		} catch (e: Exception) {
 			e.printStackTraceDebug()
-			currentState = currentState.copy(error = e.getDisplayMessage(applicationContext.resources), eta = -1L)
-			Result.failure(currentState.toWorkData())
+			Result.failure(
+				currentState.copy(
+					error = e.getDisplayMessage(applicationContext.resources),
+					eta = -1L,
+				).toWorkData(),
+			)
+		} finally {
+			notificationManager.cancel(id.hashCode())
 		}
 	}
 
 	override suspend fun getForegroundInfo() = ForegroundInfo(
 		id.hashCode(),
-		notificationFactory.create(null),
+		notificationFactory.create(lastPublishedState),
 	)
 
-	private suspend fun downloadMangaImpl(chaptersIds: LongArray?) {
+	private suspend fun downloadMangaImpl(
+		includedIds: LongArray?,
+		excludedIds: LongArray,
+	) {
 		var manga = currentState.manga
-		val chaptersIdsSet = chaptersIds?.toMutableSet()
+		val chaptersToSkip = excludedIds.toMutableSet()
 		withMangaLock(manga) {
 			ContextCompat.registerReceiver(
 				applicationContext,
@@ -135,26 +152,24 @@ class DownloadWorker @AssistedInject constructor(
 						?: error("Cannot obtain remote manga instance")
 				}
 				val repo = mangaRepositoryFactory.create(manga.source)
-				val data = if (manga.chapters.isNullOrEmpty()) repo.getDetails(manga) else manga
-				output = LocalMangaOutput.getOrCreate(destination, data)
-				val coverUrl = data.largeCoverUrl.ifNullOrEmpty { data.coverUrl }
+				val mangaDetails = if (manga.chapters.isNullOrEmpty()) repo.getDetails(manga) else manga
+				output = LocalMangaOutput.getOrCreate(destination, mangaDetails)
+				val coverUrl = mangaDetails.largeCoverUrl.ifNullOrEmpty { mangaDetails.coverUrl }
 				if (coverUrl.isNotEmpty()) {
 					downloadFile(coverUrl, destination, tempFileName, repo.source).let { file ->
 						output.addCover(file, MimeTypeMap.getFileExtensionFromUrl(coverUrl))
 					}
 				}
-				val chapters = checkNotNull(
-					if (chaptersIdsSet == null) {
-						data.chapters
-					} else {
-						data.chapters?.filter { x -> chaptersIdsSet.remove(x.id) }
-					},
-				) { "Chapters list must not be null" }
-				check(chapters.isNotEmpty()) { "Chapters list must not be empty" }
-				check(chaptersIdsSet.isNullOrEmpty()) {
-					"${chaptersIdsSet?.size} of ${chaptersIds?.size} requested chapters not found in manga"
-				}
+				val chapters = getChapters(mangaDetails, includedIds)
 				for ((chapterIndex, chapter) in chapters.withIndex()) {
+					if (chaptersToSkip.remove(chapter.id)) {
+						publishState(
+							currentState.copy(
+								downloadedChapters = currentState.downloadedChapters + chapter.id,
+							),
+						)
+						continue
+					}
 					val pages = runFailsafe(pausingHandle) {
 						repo.getPages(chapter)
 					}
@@ -190,6 +205,11 @@ class DownloadWorker @AssistedInject constructor(
 							localStorageChanges.emit(LocalMangaInput.of(output.rootFile).getManga())
 						}.onFailure(Throwable::printStackTraceDebug)
 					}
+					publishState(
+						currentState.copy(
+							downloadedChapters = currentState.downloadedChapters + chapter.id,
+						),
+					)
 				}
 				publishState(currentState.copy(isIndeterminate = true, eta = -1L))
 				output.mergeWithExisting()
@@ -273,7 +293,7 @@ class DownloadWorker @AssistedInject constructor(
 
 	private suspend fun publishState(state: DownloadState2) {
 		val previousState = currentState
-		currentState = state
+		lastPublishedState = state
 		if (previousState.isParticularProgress && state.isParticularProgress) {
 			timeLeftEstimator.tick(state.progress, state.max)
 		} else {
@@ -291,6 +311,30 @@ class DownloadWorker @AssistedInject constructor(
 		setProgress(state.toWorkData())
 	}
 
+	private suspend fun getDoneChapters(): LongArray {
+		val work = WorkManagerHelper(WorkManager.getInstance(applicationContext)).getWorkInfoById(id)
+			?: return LongArray(0)
+		return DownloadState2.getDownloadedChapters(work.progress)
+	}
+
+	private fun getChapters(
+		manga: Manga,
+		includedIds: LongArray?,
+	): List<MangaChapter> {
+		val chapters = checkNotNull(manga.chapters?.toMutableList()) {
+			"Chapters list must not be null"
+		}
+		if (includedIds != null) {
+			val chaptersIdsSet = includedIds.toMutableSet()
+			chapters.retainAll { x -> chaptersIdsSet.remove(x.id) }
+			check(chaptersIdsSet.isEmpty()) {
+				"${chaptersIdsSet.size} of ${includedIds.size} requested chapters not found in manga"
+			}
+		}
+		check(chapters.isNotEmpty()) { "Chapters list must not be empty" }
+		return chapters
+	}
+
 	private suspend inline fun <T> withMangaLock(manga: Manga, block: () -> T) = try {
 		localMangaRepository.lockManga(manga.id)
 		block()

app/src/main/java/org/koitharu/kotatsu/utils/WorkManagerHelper.kt

@@ -57,6 +57,10 @@ class WorkManagerHelper(
 		return workManagerImpl.getWorkInfos(query).await()
 	}
 
+	suspend fun getWorkInfoById(id: UUID): WorkInfo? {
+		return workManagerImpl.getWorkInfoById(id).await()
+	}
+
 	suspend fun updateWork(request: WorkRequest): WorkManager.UpdateResult {
 		return workManagerImpl.updateWork(request).await()
 	}