Show related manga

app/src/main/kotlin/org/koitharu/kotatsu/details/domain/RelatedMangaUseCase.kt

@@ -0,0 +1,18 @@
+package org.koitharu.kotatsu.details.domain
+
+import org.koitharu.kotatsu.core.parser.MangaRepository
+import org.koitharu.kotatsu.core.util.ext.printStackTraceDebug
+import org.koitharu.kotatsu.parsers.model.Manga
+import org.koitharu.kotatsu.parsers.util.runCatchingCancellable
+import javax.inject.Inject
+
+class RelatedMangaUseCase @Inject constructor(
+	private val mangaRepositoryFactory: MangaRepository.Factory,
+) {
+
+	suspend operator fun invoke(seed: Manga) = runCatchingCancellable {
+		mangaRepositoryFactory.create(seed.source).getRelated(seed)
+	}.onFailure {
+		it.printStackTraceDebug()
+	}.getOrNull()
+}

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

@@ -24,6 +24,7 @@ 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.ui.BaseFragment
+import org.koitharu.kotatsu.core.ui.BaseListAdapter
 import org.koitharu.kotatsu.core.ui.image.CoverSizeResolver
 import org.koitharu.kotatsu.core.ui.list.OnListItemClickListener
 import org.koitharu.kotatsu.core.ui.list.decor.SpacingItemDecoration
@@ -45,6 +46,9 @@ import org.koitharu.kotatsu.details.ui.scrobbling.ScrollingInfoAdapter
 import org.koitharu.kotatsu.history.data.PROGRESS_NONE
 import org.koitharu.kotatsu.image.ui.ImageActivity
 import org.koitharu.kotatsu.list.domain.ListExtraProvider
+import org.koitharu.kotatsu.list.ui.adapter.mangaGridItemAD
+import org.koitharu.kotatsu.list.ui.model.MangaItemModel
+import org.koitharu.kotatsu.list.ui.size.StaticItemSizeResolver
 import org.koitharu.kotatsu.main.ui.owners.NoModalBottomSheetOwner
 import org.koitharu.kotatsu.parsers.model.Manga
 import org.koitharu.kotatsu.parsers.model.MangaSource
@@ -87,6 +91,9 @@ class DetailsFragment :
 		binding.infoLayout.textViewSource.setOnClickListener(this)
 		binding.textViewDescription.movementMethod = LinkMovementMethod.getInstance()
 		binding.chipsTags.onChipClickListener = this
+		binding.recyclerViewRelated.addItemDecoration(
+			SpacingItemDecoration(resources.getDimensionPixelOffset(R.dimen.grid_spacing)),
+		)
 		TitleScrollCoordinator(binding.textViewTitle).attach(binding.scrollView)
 		viewModel.manga.filterNotNull().observe(viewLifecycleOwner, ::onMangaUpdated)
 		viewModel.isLoading.observe(viewLifecycleOwner, ::onLoadingStateChanged)
@@ -96,6 +103,7 @@ class DetailsFragment :
 		viewModel.description.observe(viewLifecycleOwner, ::onDescriptionChanged)
 		viewModel.chapters.observe(viewLifecycleOwner, ::onChaptersChanged)
 		viewModel.localSize.observe(viewLifecycleOwner, ::onLocalSizeChanged)
+		viewModel.relatedManga.observe(viewLifecycleOwner, ::onRelatedMangaChanged)
 	}
 
 	override fun onItemClick(item: Bookmark, view: View) {
@@ -193,6 +201,24 @@ class DetailsFragment :
 		}
 	}
 
+	private fun onRelatedMangaChanged(related: List<MangaItemModel>) {
+		if (related.isEmpty()) {
+			requireViewBinding().groupRelated.isVisible = false
+			return
+		}
+		val rv = viewBinding?.recyclerViewRelated ?: return
+		val adapter = (rv.adapter as? BaseListAdapter) ?: BaseListAdapter(
+			mangaGridItemAD(
+				coil, viewLifecycleOwner,
+				StaticItemSizeResolver(resources.getDimensionPixelSize(R.dimen.smaller_grid_width)),
+			) { item, view ->
+				startActivity(DetailsActivity.newIntent(view.context, item), scaleUpActivityOptionsOf(view))
+			},
+		).also { rv.adapter = it }
+		adapter.items = related
+		requireViewBinding().groupRelated.isVisible = true
+	}
+
 	private fun onHistoryChanged(history: HistoryInfo) {
 		requireViewBinding().progressView.setPercent(history.history?.percent ?: PROGRESS_NONE, animate = true)
 	}

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

@@ -23,6 +23,7 @@ import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.flow.flatMapLatest
 import kotlinx.coroutines.flow.flowOf
 import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.flow.mapLatest
 import kotlinx.coroutines.flow.stateIn
 import kotlinx.coroutines.flow.transformLatest
 import kotlinx.coroutines.flow.update
@@ -34,6 +35,7 @@ import org.koitharu.kotatsu.core.model.getPreferredBranch
 import org.koitharu.kotatsu.core.os.NetworkState
 import org.koitharu.kotatsu.core.parser.MangaIntent
 import org.koitharu.kotatsu.core.prefs.AppSettings
+import org.koitharu.kotatsu.core.prefs.ListMode
 import org.koitharu.kotatsu.core.prefs.observeAsStateFlow
 import org.koitharu.kotatsu.core.ui.BaseViewModel
 import org.koitharu.kotatsu.core.util.ext.MutableEventFlow
@@ -46,12 +48,16 @@ import org.koitharu.kotatsu.core.util.ext.toFileOrNull
 import org.koitharu.kotatsu.details.domain.BranchComparator
 import org.koitharu.kotatsu.details.domain.DetailsInteractor
 import org.koitharu.kotatsu.details.domain.DoubleMangaLoadUseCase
+import org.koitharu.kotatsu.details.domain.RelatedMangaUseCase
 import org.koitharu.kotatsu.details.domain.model.DoubleManga
 import org.koitharu.kotatsu.details.ui.model.ChapterListItem
 import org.koitharu.kotatsu.details.ui.model.HistoryInfo
 import org.koitharu.kotatsu.details.ui.model.MangaBranch
 import org.koitharu.kotatsu.download.ui.worker.DownloadWorker
 import org.koitharu.kotatsu.history.data.HistoryRepository
+import org.koitharu.kotatsu.list.domain.ListExtraProvider
+import org.koitharu.kotatsu.list.ui.model.MangaItemModel
+import org.koitharu.kotatsu.list.ui.model.toUi
 import org.koitharu.kotatsu.local.data.LocalStorageChanges
 import org.koitharu.kotatsu.local.domain.DeleteLocalMangaUseCase
 import org.koitharu.kotatsu.local.domain.model.LocalManga
@@ -74,6 +80,8 @@ class DetailsViewModel @Inject constructor(
 	savedStateHandle: SavedStateHandle,
 	private val deleteLocalMangaUseCase: DeleteLocalMangaUseCase,
 	private val doubleMangaLoadUseCase: DoubleMangaLoadUseCase,
+	private val relatedMangaUseCase: RelatedMangaUseCase,
+	private val extraProvider: ListExtraProvider,
 	networkState: NetworkState,
 ) : BaseViewModel() {
 
@@ -155,6 +163,18 @@ class DetailsViewModel @Inject constructor(
 	val scrobblingInfo: StateFlow<List<ScrobblingInfo>> = interactor.observeScrobblingInfo(mangaId)
 		.stateIn(viewModelScope + Dispatchers.Default, SharingStarted.Eagerly, emptyList())
 
+	val relatedManga: StateFlow<List<MangaItemModel>> = doubleManga.map {
+		it?.remote
+	}.distinctUntilChangedBy { it?.id }
+		.mapLatest {
+			if (it != null) {
+				relatedMangaUseCase.invoke(it)?.toUi(ListMode.GRID, extraProvider).orEmpty()
+			} else {
+				emptyList()
+			}
+		}
+		.stateIn(viewModelScope, SharingStarted.Lazily, emptyList())
+
 	val branches: StateFlow<List<MangaBranch>> = combine(
 		doubleManga,
 		selectedBranch,