Show reason why manga has no chapters

app/src/main/kotlin/org/koitharu/kotatsu/core/exceptions/resolve/CaptchaHandler.kt

@@ -104,14 +104,14 @@ class CaptchaHandler @Inject constructor(
 			val dao = databaseProvider.get().getSourcesDao()
 			dao.setCfState(source.name, exception?.state ?: CloudFlareHelper.PROTECTION_NOT_DETECTED)
 
-			val exceptions = dao.findAllCaptchaRequired().mapNotNull {
-				it.source.toMangaSourceOrNull()
-			}.filterNot {
-				SourceSettings(context, it).isCaptchaNotificationsDisabled
-			}.mapNotNull {
-				exceptionMap[it]
-			}
 			if (notify && context.checkNotificationPermission(CHANNEL_ID)) {
+				val exceptions = dao.findAllCaptchaRequired().mapNotNull {
+					it.source.toMangaSourceOrNull()
+				}.filterNot {
+					SourceSettings(context, it).isCaptchaNotificationsDisabled
+				}.mapNotNull {
+					exceptionMap[it]
+				}
 				if (removedException != null) {
 					NotificationManagerCompat.from(context).cancel(TAG, removedException.source.hashCode())
 				}

app/src/main/kotlin/org/koitharu/kotatsu/details/ui/pager/ChapterPagesMenuProvider.kt

@@ -39,7 +39,7 @@ class ChapterPagesMenuProvider(
 					setOnActionExpandListener(this@ChapterPagesMenuProvider)
 					(actionView as? SearchView)?.setupChaptersSearchView()
 				}
-				menu.findItem(R.id.action_search)?.isVisible = viewModel.isChaptersEmpty.value == false
+				menu.findItem(R.id.action_search)?.isVisible = viewModel.emptyReason.value == null
 				menu.findItem(R.id.action_reversed)?.isChecked = viewModel.isChaptersReversed.value == true
 				menu.findItem(R.id.action_grid_view)?.isChecked = viewModel.isChaptersInGridView.value == true
 				menu.findItem(R.id.action_downloaded)?.let { menuItem ->

app/src/main/kotlin/org/koitharu/kotatsu/details/ui/pager/ChaptersPagesViewModel.kt

@@ -14,6 +14,7 @@ import kotlinx.coroutines.flow.distinctUntilChanged
 import kotlinx.coroutines.flow.flatMapLatest
 import kotlinx.coroutines.flow.flowOf
 import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.flow.onStart
 import kotlinx.coroutines.flow.stateIn
 import kotlinx.coroutines.flow.update
 import kotlinx.coroutines.plus
@@ -43,6 +44,7 @@ import org.koitharu.kotatsu.list.domain.ListFilterOption
 import org.koitharu.kotatsu.local.domain.DeleteLocalMangaUseCase
 import org.koitharu.kotatsu.local.domain.model.LocalManga
 import org.koitharu.kotatsu.parsers.model.Manga
+import org.koitharu.kotatsu.parsers.model.MangaState
 import org.koitharu.kotatsu.reader.ui.ReaderActivity
 import org.koitharu.kotatsu.reader.ui.ReaderState
 import org.koitharu.kotatsu.reader.ui.ReaderViewModel
@@ -97,9 +99,19 @@ abstract class ChaptersPagesViewModel(
 		}
 	}.stateIn(viewModelScope + Dispatchers.Default, SharingStarted.Eagerly, 0)
 
-	val isChaptersEmpty: StateFlow<Boolean> = mangaDetails.map {
-		it != null && it.isLoaded && it.allChapters.isEmpty()
-	}.stateIn(viewModelScope, SharingStarted.WhileSubscribed(), false)
+	val emptyReason: StateFlow<EmptyMangaReason?> = combine(
+		mangaDetails,
+		isLoading,
+		onError.onStart { emit(null) },
+	) { details, loading, error ->
+		when {
+			details == null || loading -> null
+			details.chapters.isNotEmpty() -> null
+			details.toManga().state == MangaState.RESTRICTED -> EmptyMangaReason.RESTRICTED
+			error != null -> EmptyMangaReason.LOADING_ERROR
+			else -> EmptyMangaReason.NO_CHAPTERS
+		}
+	}.stateIn(viewModelScope + Dispatchers.Default, SharingStarted.WhileSubscribed(), null)
 
 	val bookmarks = mangaDetails.flatMapLatest {
 		if (it != null) {

app/src/main/kotlin/org/koitharu/kotatsu/details/ui/pager/EmptyMangaReason.kt

@@ -0,0 +1,13 @@
+package org.koitharu.kotatsu.details.ui.pager
+
+import androidx.annotation.StringRes
+import org.koitharu.kotatsu.R
+
+enum class EmptyMangaReason(
+	@StringRes val msgResId: Int,
+) {
+
+	NO_CHAPTERS(R.string.no_chapters_in_manga),
+	LOADING_ERROR(R.string.chapters_load_failed),
+	RESTRICTED(R.string.manga_restricted_description),
+}

app/src/main/kotlin/org/koitharu/kotatsu/details/ui/pager/chapters/ChaptersFragment.kt

@@ -30,6 +30,7 @@ import org.koitharu.kotatsu.core.util.RecyclerViewScrollCallback
 import org.koitharu.kotatsu.core.util.ext.findAppCompatDelegate
 import org.koitharu.kotatsu.core.util.ext.findParentCallback
 import org.koitharu.kotatsu.core.util.ext.observe
+import org.koitharu.kotatsu.core.util.ext.setTextAndVisible
 import org.koitharu.kotatsu.databinding.FragmentChaptersBinding
 import org.koitharu.kotatsu.details.ui.adapter.ChaptersAdapter
 import org.koitharu.kotatsu.details.ui.adapter.ChaptersSelectionDecoration
@@ -96,8 +97,8 @@ class ChaptersFragment :
 			.flowOn(Dispatchers.Default)
 			.observe(viewLifecycleOwner, this::onChaptersChanged)
 		viewModel.quickFilter.observe(viewLifecycleOwner, this::onFilterChanged)
-		viewModel.isChaptersEmpty.observe(viewLifecycleOwner) {
-			binding.textViewHolder.isVisible = it
+		viewModel.emptyReason.observe(viewLifecycleOwner) {
+			binding.textViewHolder.setTextAndVisible(it?.msgResId ?: 0)
 		}
 	}
 

app/src/main/kotlin/org/koitharu/kotatsu/details/ui/pager/pages/PagesFragment.kt

@@ -11,7 +11,6 @@ import androidx.appcompat.view.ActionMode
 import androidx.collection.ArraySet
 import androidx.core.view.WindowInsetsCompat
 import androidx.core.view.isInvisible
-import androidx.core.view.isVisible
 import androidx.fragment.app.viewModels
 import androidx.recyclerview.widget.GridLayoutManager
 import androidx.recyclerview.widget.RecyclerView
@@ -37,9 +36,11 @@ import org.koitharu.kotatsu.core.util.ext.findAppCompatDelegate
 import org.koitharu.kotatsu.core.util.ext.findParentCallback
 import org.koitharu.kotatsu.core.util.ext.observe
 import org.koitharu.kotatsu.core.util.ext.observeEvent
+import org.koitharu.kotatsu.core.util.ext.setTextAndVisible
 import org.koitharu.kotatsu.core.util.ext.showOrHide
 import org.koitharu.kotatsu.databinding.FragmentPagesBinding
 import org.koitharu.kotatsu.details.ui.pager.ChaptersPagesViewModel
+import org.koitharu.kotatsu.details.ui.pager.EmptyMangaReason
 import org.koitharu.kotatsu.list.ui.GridSpanResolver
 import org.koitharu.kotatsu.list.ui.adapter.ListItemType
 import org.koitharu.kotatsu.list.ui.adapter.TypedListSpacingDecoration
@@ -125,11 +126,18 @@ class PagesFragment :
 				it.spanCount = checkNotNull(spanResolver).spanCount
 			}
 		}
-		parentViewModel.isChaptersEmpty.observe(viewLifecycleOwner, ::onNoChaptersChanged)
+		parentViewModel.emptyReason.observe(viewLifecycleOwner, ::onNoChaptersChanged)
 		viewModel.thumbnails.observe(viewLifecycleOwner, ::onThumbnailsChanged)
 		viewModel.onPageSaved.observeEvent(this, PagesSavedObserver(binding.recyclerView))
 		viewModel.onError.observeEvent(viewLifecycleOwner, SnackbarErrorObserver(binding.recyclerView, this))
-		viewModel.isLoading.observe(viewLifecycleOwner) { binding.progressBar.showOrHide(it) }
+		combine(
+			viewModel.isLoading,
+			viewModel.thumbnails,
+		) { loading, content ->
+			loading && content.isEmpty()
+		}.observe(viewLifecycleOwner) {
+			binding.progressBar.showOrHide(it)
+		}
 		viewModel.isLoadingUp.observe(viewLifecycleOwner) { binding.progressBarTop.showOrHide(it) }
 		viewModel.isLoadingDown.observe(viewLifecycleOwner) { binding.progressBarBottom.showOrHide(it) }
 	}
@@ -237,10 +245,10 @@ class PagesFragment :
 		spanResolver?.setGridSize(scale, requireViewBinding().recyclerView)
 	}
 
-	private fun onNoChaptersChanged(isNoChapters: Boolean) {
+	private fun onNoChaptersChanged(reason: EmptyMangaReason?) {
 		with(viewBinding ?: return) {
-			textViewHolder.isVisible = isNoChapters
-			recyclerView.isInvisible = isNoChapters
+			textViewHolder.setTextAndVisible(reason?.msgResId ?: 0)
+			recyclerView.isInvisible = reason != null
 		}
 	}
 

app/src/main/kotlin/org/koitharu/kotatsu/details/ui/pager/pages/PagesViewModel.kt

@@ -5,8 +5,9 @@ import androidx.lifecycle.viewModelScope
 import dagger.hilt.android.lifecycle.HiltViewModel
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.Job
+import kotlinx.coroutines.cancelAndJoin
 import kotlinx.coroutines.flow.MutableStateFlow
-import kotlinx.coroutines.flow.collectLatest
+import kotlinx.coroutines.flow.filterNotNull
 import kotlinx.coroutines.plus
 import org.koitharu.kotatsu.core.prefs.AppSettings
 import org.koitharu.kotatsu.core.prefs.observeAsStateFlow
@@ -47,16 +48,15 @@ class PagesViewModel @Inject constructor(
 	)
 
 	init {
-		loadingJob = launchLoadingJob(Dispatchers.Default) {
-			val firstState = state.firstNotNull()
-			doInit(firstState)
-			launchJob(Dispatchers.Default) {
-				state.collectLatest {
-					if (it != null) {
+		launchJob(Dispatchers.Default) {
+			state.filterNotNull()
+				.collect {
+					val prevJob = loadingJob
+					loadingJob = launchLoadingJob(Dispatchers.Default) {
+						prevJob?.cancelAndJoin()
 						doInit(it)
 					}
 				}
-			}
 		}
 	}
 

app/src/main/res/values/strings.xml

@@ -875,4 +875,7 @@
 	<string name="invalid_token">Invalid token: %s</string>
 	<string name="show_floating_control_button">Show floating control button</string>
 	<string name="unavailable">Unavailable</string>
+	<string name="manga_restricted_description">This manga is not available to read in this source. Try searching for it in other sources or opening it in a browser for more information</string>
+	<string name="no_chapters_in_manga">This manga does not contain any chapters</string>
+	<string name="chapters_load_failed">Failed to load chapter list</string>
 </resources>