Fix chapters counter

app/src/main/java/org/koitharu/kotatsu/core/model/Manga.kt

@@ -1,6 +1,7 @@
 package org.koitharu.kotatsu.core.model
 
 import androidx.core.os.LocaleListCompat
+import org.koitharu.kotatsu.details.ui.model.ChapterListItem
 import org.koitharu.kotatsu.parsers.model.Manga
 import org.koitharu.kotatsu.parsers.util.mapToSet
 import org.koitharu.kotatsu.parsers.util.toTitleCase
@@ -8,6 +9,18 @@ import org.koitharu.kotatsu.utils.ext.iterator
 
 fun Collection<Manga>.ids() = mapToSet { it.id }
 
+fun Collection<ChapterListItem>.countChaptersByBranch(): Int {
+	if (size <= 1) {
+		return size
+	}
+	val acc = HashMap<String?, Int>()
+	for (item in this) {
+		val branch = item.chapter.branch
+		acc[branch] = (acc[branch] ?: 0) + 1
+	}
+	return acc.values.max()
+}
+
 fun Manga.getPreferredBranch(history: MangaHistory?): String? {
 	val ch = chapters
 	if (ch.isNullOrEmpty()) {
@@ -31,4 +44,4 @@ fun Manga.getPreferredBranch(history: MangaHistory?): String? {
 		}
 	}
 	return groups.maxByOrNull { it.value.size }?.key
-}
+}

app/src/main/java/org/koitharu/kotatsu/details/ui/DetailsFragment.kt

@@ -27,6 +27,7 @@ import org.koitharu.kotatsu.base.ui.list.decor.SpacingItemDecoration
 import org.koitharu.kotatsu.base.ui.widgets.ChipsView
 import org.koitharu.kotatsu.bookmarks.domain.Bookmark
 import org.koitharu.kotatsu.bookmarks.ui.adapter.BookmarksAdapter
+import org.koitharu.kotatsu.core.model.countChaptersByBranch
 import org.koitharu.kotatsu.core.parser.MangaTagHighlighter
 import org.koitharu.kotatsu.databinding.FragmentDetailsBinding
 import org.koitharu.kotatsu.details.ui.model.ChapterListItem
@@ -177,12 +178,9 @@ class DetailsFragment :
 		if (chapters.isNullOrEmpty()) {
 			infoLayout.textViewChapters.isVisible = false
 		} else {
+			val count = chapters.countChaptersByBranch()
 			infoLayout.textViewChapters.isVisible = true
-			infoLayout.textViewChapters.text = resources.getQuantityString(
-				R.plurals.chapters,
-				chapters.size,
-				chapters.size,
-			)
+			infoLayout.textViewChapters.text = resources.getQuantityString(R.plurals.chapters, count, count)
 		}
 	}
 

app/src/main/java/org/koitharu/kotatsu/details/ui/DetailsViewModel.kt

@@ -95,13 +95,14 @@ class DetailsViewModel @Inject constructor(
 
 	val historyInfo: LiveData<HistoryInfo> = combine(
 		delegate.manga,
+		delegate.selectedBranch,
 		history,
 		historyRepository.observeShouldSkip(delegate.manga),
-	) { m, h, im ->
-		HistoryInfo(m, h, im)
+	) { m, b, h, im ->
+		HistoryInfo(m, b, h, im)
 	}.asFlowLiveData(
 		context = viewModelScope.coroutineContext + Dispatchers.Default,
-		defaultValue = HistoryInfo(null, null, false),
+		defaultValue = HistoryInfo(null, null, null, false),
 	)
 
 	val bookmarks = delegate.manga.flatMapLatest {

app/src/main/java/org/koitharu/kotatsu/details/ui/model/HistoryInfo.kt

@@ -36,8 +36,13 @@ class HistoryInfo(
 	}
 }
 
-fun HistoryInfo(manga: Manga?, history: MangaHistory?, isIncognitoMode: Boolean): HistoryInfo {
-	val chapters = manga?.chapters
+fun HistoryInfo(
+	manga: Manga?,
+	branch: String?,
+	history: MangaHistory?,
+	isIncognitoMode: Boolean
+): HistoryInfo {
+	val chapters = manga?.getChapters(branch)
 	return HistoryInfo(
 		totalChapters = chapters?.size ?: -1,
 		currentChapter = if (history != null && !chapters.isNullOrEmpty()) {

app/src/main/java/org/koitharu/kotatsu/reader/domain/PageLoader.kt

@@ -3,6 +3,7 @@ package org.koitharu.kotatsu.reader.domain
 import android.graphics.Bitmap
 import android.graphics.BitmapFactory
 import android.net.Uri
+import androidx.annotation.AnyThread
 import androidx.collection.LongSparseArray
 import androidx.collection.set
 import dagger.hilt.android.ActivityRetainedLifecycle
@@ -76,6 +77,7 @@ class PageLoader @Inject constructor(
 		return repository is RemoteMangaRepository && settings.isPagesPreloadEnabled()
 	}
 
+	@AnyThread
 	fun prefetch(pages: List<ReaderPage>) = loaderScope.launch {
 		prefetchLock.withLock {
 			for (page in pages.asReversed()) {

app/src/main/java/org/koitharu/kotatsu/reader/ui/ReaderInfoBarView.kt

@@ -15,9 +15,6 @@ import androidx.annotation.AttrRes
 import androidx.core.graphics.ColorUtils
 import androidx.core.view.ViewCompat
 import androidx.core.view.WindowInsetsCompat
-import com.google.android.material.R as materialR
-import java.text.SimpleDateFormat
-import java.util.*
 import org.koitharu.kotatsu.R
 import org.koitharu.kotatsu.parsers.util.format
 import org.koitharu.kotatsu.reader.ui.pager.ReaderUiState
@@ -25,6 +22,9 @@ import org.koitharu.kotatsu.utils.ext.getThemeColor
 import org.koitharu.kotatsu.utils.ext.measureDimension
 import org.koitharu.kotatsu.utils.ext.printStackTraceDebug
 import org.koitharu.kotatsu.utils.ext.resolveDp
+import java.text.SimpleDateFormat
+import java.util.Date
+import com.google.android.material.R as materialR
 
 class ReaderInfoBarView @JvmOverloads constructor(
 	context: Context,
@@ -121,15 +121,14 @@ class ReaderInfoBarView @JvmOverloads constructor(
 
 	fun update(state: ReaderUiState?) {
 		text = if (state != null) {
-			val percent = state.computePercent()
 			context.getString(
 				R.string.reader_info_pattern,
 				state.chapterNumber,
 				state.chaptersTotal,
 				state.currentPage + 1,
 				state.totalPages,
-			) + if (percent in 0f..1f) {
-				"     " + context.getString(R.string.percent_string_pattern, (percent * 100).format())
+			) + if (state.percent in 0f..1f) {
+				"     " + context.getString(R.string.percent_string_pattern, (state.percent * 100).format())
 			} else {
 				""
 			}

app/src/main/java/org/koitharu/kotatsu/reader/ui/ReaderViewModel.kt

@@ -4,6 +4,8 @@ import android.net.Uri
 import android.util.LongSparseArray
 import androidx.activity.result.ActivityResultLauncher
 import androidx.annotation.AnyThread
+import androidx.annotation.MainThread
+import androidx.annotation.WorkerThread
 import androidx.lifecycle.LiveData
 import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.SavedStateHandle
@@ -13,6 +15,7 @@ import kotlinx.coroutines.CancellationException
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.Job
 import kotlinx.coroutines.cancelAndJoin
+import kotlinx.coroutines.ensureActive
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.SharingStarted
 import kotlinx.coroutines.flow.combine
@@ -80,6 +83,7 @@ class ReaderViewModel @Inject constructor(
 	private var loadingJob: Job? = null
 	private var pageSaveJob: Job? = null
 	private var bookmarkJob: Job? = null
+	private var stateChangeJob: Job? = null
 	private val currentState = MutableStateFlow<ReaderState?>(savedStateHandle[ReaderActivity.EXTRA_STATE])
 	private val mangaData = MutableStateFlow(intent.manga)
 	private val chapters: LongSparseArray<MangaChapter>
@@ -143,7 +147,7 @@ class ReaderViewModel @Inject constructor(
 		settings.observe()
 			.onEach { key ->
 				if (key == AppSettings.KEY_READER_SLIDER) notifyStateChanged()
-			}.launchIn(viewModelScope)
+			}.launchIn(viewModelScope + Dispatchers.Default)
 	}
 
 	fun reload() {
@@ -234,26 +238,31 @@ class ReaderViewModel @Inject constructor(
 		}
 	}
 
-	// TODO move to background?
+	@MainThread
 	fun onCurrentPageChanged(position: Int) {
-		val pages = content.value?.pages ?: return
-		pages.getOrNull(position)?.let { page ->
-			currentState.update { cs ->
-				cs?.copy(chapterId = page.chapterId, page = page.index)
+		val prevJob = stateChangeJob
+		stateChangeJob = launchJob(Dispatchers.Default) {
+			prevJob?.cancelAndJoin()
+			val pages = content.value?.pages ?: return@launchJob
+			pages.getOrNull(position)?.let { page ->
+				currentState.update { cs ->
+					cs?.copy(chapterId = page.chapterId, page = page.index)
+				}
+			}
+			notifyStateChanged()
+			if (pages.isEmpty() || loadingJob?.isActive == true) {
+				return@launchJob
+			}
+			ensureActive()
+			if (position <= BOUNDS_PAGE_OFFSET) {
+				loadPrevNextChapter(pages.first().chapterId, isNext = false)
+			}
+			if (position >= pages.lastIndex - BOUNDS_PAGE_OFFSET) {
+				loadPrevNextChapter(pages.last().chapterId, isNext = true)
+			}
+			if (pageLoader.isPrefetchApplicable()) {
+				pageLoader.prefetch(pages.trySublist(position + 1, position + PREFETCH_LIMIT))
 			}
-		}
-		notifyStateChanged()
-		if (pages.isEmpty() || loadingJob?.isActive == true) {
-			return
-		}
-		if (position <= BOUNDS_PAGE_OFFSET) {
-			loadPrevNextChapter(pages.first().chapterId, isNext = false)
-		}
-		if (position >= pages.size - BOUNDS_PAGE_OFFSET) {
-			loadPrevNextChapter(pages.last().chapterId, isNext = true)
-		}
-		if (pageLoader.isPrefetchApplicable()) {
-			pageLoader.prefetch(pages.trySublist(position + 1, position + PREFETCH_LIMIT))
 		}
 	}
 
@@ -328,6 +337,7 @@ class ReaderViewModel @Inject constructor(
 		}
 	}
 
+	@AnyThread
 	private fun loadPrevNextChapter(currentId: Long, isNext: Boolean) {
 		loadingJob = launchLoadingJob(Dispatchers.Default) {
 			chaptersLoader.loadPrevNextChapter(mangaData.requireValue(), currentId, isNext)
@@ -365,7 +375,7 @@ class ReaderViewModel @Inject constructor(
 		}.getOrDefault(defaultMode)
 	}
 
-	@AnyThread
+	@WorkerThread
 	private fun notifyStateChanged() {
 		val state = getCurrentState()
 		val chapter = state?.chapterId?.let(chapters::get)
@@ -373,10 +383,11 @@ class ReaderViewModel @Inject constructor(
 			mangaName = manga?.title,
 			chapterName = chapter?.name,
 			chapterNumber = chapter?.number ?: 0,
-			chaptersTotal = chapters.size(),
+			chaptersTotal = manga?.getChapters(chapter?.branch)?.size ?: 0,
 			totalPages = if (chapter != null) chaptersLoader.getPagesCount(chapter.id) else 0,
 			currentPage = state?.page ?: 0,
 			isSliderEnabled = settings.isReaderSliderEnabled,
+			percent = if (state != null) computePercent(state.chapterId, state.page) else PROGRESS_NONE,
 		)
 		uiState.postValue(newState)
 	}

app/src/main/java/org/koitharu/kotatsu/reader/ui/pager/ReaderUiState.kt

@@ -7,17 +7,11 @@ data class ReaderUiState(
 	val chaptersTotal: Int,
 	val currentPage: Int,
 	val totalPages: Int,
+	val percent: Float,
 	private val isSliderEnabled: Boolean,
 ) {
 
 	fun isSliderAvailable(): Boolean {
 		return isSliderEnabled && totalPages > 1 && currentPage < totalPages
 	}
-
-	fun computePercent(): Float {
-		val ppc = 1f / chaptersTotal
-		val chapterIndex = chapterNumber - 1
-		val pagePercent = (currentPage + 1) / totalPages.toFloat()
-		return ppc * chapterIndex + ppc * pagePercent
-	}
 }