Undo deletion from favourites

app/src/main/java/org/koitharu/kotatsu/favourites/data/FavouritesDao.kt

@@ -87,6 +87,10 @@ abstract class FavouritesDao {
 	@Query("UPDATE favourites SET deleted_at = :now WHERE manga_id = :mangaId AND category_id = :categoryId")
 	abstract suspend fun delete(categoryId: Long, mangaId: Long, now: Long = System.currentTimeMillis())
 
+	suspend fun recover(mangaId: Long) = delete(mangaId, 0L)
+
+	suspend fun recover(categoryId: Long, mangaId: Long) = delete(categoryId, mangaId, 0L)
+
 	@Query("DELETE FROM favourites WHERE deleted_at != 0")
 	abstract suspend fun gc()
 

app/src/main/java/org/koitharu/kotatsu/favourites/domain/FavouritesRepository.kt

@@ -2,6 +2,7 @@ package org.koitharu.kotatsu.favourites.domain
 
 import androidx.room.withTransaction
 import kotlinx.coroutines.flow.*
+import org.koitharu.kotatsu.base.domain.ReversibleHandle
 import org.koitharu.kotatsu.core.db.MangaDatabase
 import org.koitharu.kotatsu.core.db.entity.*
 import org.koitharu.kotatsu.core.model.FavouriteCategory
@@ -117,20 +118,22 @@ class FavouritesRepository(
 		}
 	}
 
-	suspend fun removeFromFavourites(ids: Collection<Long>) {
+	suspend fun removeFromFavourites(ids: Collection<Long>): ReversibleHandle {
 		db.withTransaction {
 			for (id in ids) {
 				db.favouritesDao.delete(id)
 			}
 		}
+		return ReversibleHandle { recoverToFavourites(ids) }
 	}
 
-	suspend fun removeFromCategory(categoryId: Long, ids: Collection<Long>) {
+	suspend fun removeFromCategory(categoryId: Long, ids: Collection<Long>): ReversibleHandle {
 		db.withTransaction {
 			for (id in ids) {
 				db.favouritesDao.delete(categoryId, id)
 			}
 		}
+		return ReversibleHandle { recoverToCategory(categoryId, ids) }
 	}
 
 	private fun observeOrder(categoryId: Long): Flow<SortOrder> {
@@ -139,4 +142,20 @@ class FavouritesRepository(
 			.map { x -> SortOrder(x.order, SortOrder.NEWEST) }
 			.distinctUntilChanged()
 	}
+
+	private suspend fun recoverToFavourites(ids: Collection<Long>) {
+		db.withTransaction {
+			for (id in ids) {
+				db.favouritesDao.recover(id)
+			}
+		}
+	}
+
+	private suspend fun recoverToCategory(categoryId: Long, ids: Collection<Long>) {
+		db.withTransaction {
+			for (id in ids) {
+				db.favouritesDao.recover(categoryId, id)
+			}
+		}
+	}
 }

app/src/main/java/org/koitharu/kotatsu/favourites/ui/list/FavouritesListFragment.kt

@@ -7,9 +7,12 @@ import android.view.MenuItem
 import android.view.View
 import androidx.appcompat.view.ActionMode
 import androidx.core.view.iterator
+import com.google.android.material.snackbar.Snackbar
 import org.koin.androidx.viewmodel.ext.android.viewModel
 import org.koin.core.parameter.parametersOf
 import org.koitharu.kotatsu.R
+import org.koitharu.kotatsu.base.domain.ReversibleHandle
+import org.koitharu.kotatsu.base.domain.reverseAsync
 import org.koitharu.kotatsu.core.ui.titleRes
 import org.koitharu.kotatsu.favourites.ui.categories.CategoriesActivity
 import org.koitharu.kotatsu.list.ui.MangaListFragment
@@ -30,6 +33,7 @@ class FavouritesListFragment : MangaListFragment() {
 	override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
 		super.onViewCreated(view, savedInstanceState)
 		viewModel.sortOrder.observe(viewLifecycleOwner) { activity?.invalidateOptionsMenu() }
+		viewModel.onItemsRemoved.observe(viewLifecycleOwner, ::onItemsRemoved)
 	}
 
 	override fun onScrolledToEnd() = Unit
@@ -94,6 +98,15 @@ class FavouritesListFragment : MangaListFragment() {
 		}
 	}
 
+	private fun onItemsRemoved(reversibleHandle: ReversibleHandle) {
+		val message = viewModel.categoryName?.let {
+			getString(R.string.removed_from_s, it)
+		} ?: getString(R.string.removed_from_favourites)
+		Snackbar.make(binding.recyclerView, message, Snackbar.LENGTH_LONG)
+			.setAction(R.string.undo) { reversibleHandle.reverseAsync() }
+			.show()
+	}
+
 	companion object {
 
 		const val NO_ID = 0L

app/src/main/java/org/koitharu/kotatsu/favourites/ui/list/FavouritesListViewModel.kt

@@ -7,7 +7,9 @@ import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.flow.catch
 import kotlinx.coroutines.flow.combine
 import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.withContext
 import org.koitharu.kotatsu.R
+import org.koitharu.kotatsu.base.domain.ReversibleHandle
 import org.koitharu.kotatsu.core.prefs.AppSettings
 import org.koitharu.kotatsu.favourites.domain.FavouritesRepository
 import org.koitharu.kotatsu.favourites.ui.list.FavouritesListFragment.Companion.NO_ID
@@ -19,6 +21,7 @@ import org.koitharu.kotatsu.list.ui.model.toErrorState
 import org.koitharu.kotatsu.list.ui.model.toUi
 import org.koitharu.kotatsu.parsers.model.SortOrder
 import org.koitharu.kotatsu.tracker.domain.TrackingRepository
+import org.koitharu.kotatsu.utils.SingleLiveEvent
 import org.koitharu.kotatsu.utils.ext.asLiveDataDistinct
 
 class FavouritesListViewModel(
@@ -28,6 +31,9 @@ class FavouritesListViewModel(
 	settings: AppSettings,
 ) : MangaListViewModel(settings), CountersProvider {
 
+	var categoryName: String? = null
+		private set
+
 	var sortOrder: LiveData<SortOrder?> = if (categoryId == NO_ID) {
 		MutableLiveData(null)
 	} else {
@@ -63,6 +69,20 @@ class FavouritesListViewModel(
 		emit(listOf(it.toErrorState(canRetry = false)))
 	}.asLiveDataDistinct(viewModelScope.coroutineContext + Dispatchers.Default, listOf(LoadingState))
 
+	val onItemsRemoved = SingleLiveEvent<ReversibleHandle>()
+
+	init {
+		if (categoryId != NO_ID) {
+			launchJob {
+				categoryName = withContext(Dispatchers.Default) {
+					runCatching {
+						repository.getCategory(categoryId).title
+					}.getOrNull()
+				}
+			}
+		}
+	}
+
 	override fun onRefresh() = Unit
 
 	override fun onRetry() = Unit
@@ -71,12 +91,13 @@ class FavouritesListViewModel(
 		if (ids.isEmpty()) {
 			return
 		}
-		launchJob {
+		launchJob(Dispatchers.Default) {
-			if (categoryId == NO_ID) {
+			val handle = if (categoryId == NO_ID) {
 				repository.removeFromFavourites(ids)
 			} else {
 				repository.removeFromCategory(categoryId, ids)
 			}
+			onItemsRemoved.postCall(handle)
 		}
 	}
 

app/src/main/java/org/koitharu/kotatsu/history/data/HistoryDao.kt

@@ -64,6 +64,8 @@ abstract class HistoryDao {
 	@Query("UPDATE history SET deleted_at = :now WHERE manga_id = :mangaId")
 	abstract suspend fun delete(mangaId: Long, now: Long = System.currentTimeMillis())
 
+	suspend fun recover(mangaId: Long) = delete(mangaId, 0L)
+
 	@Query("DELETE FROM history WHERE deleted_at != 0")
 	abstract suspend fun gc()
 

app/src/main/java/org/koitharu/kotatsu/history/domain/HistoryRepository.kt

@@ -94,24 +94,14 @@ class HistoryRepository(
 		db.historyDao.delete(manga.id)
 	}
 
-	suspend fun delete(ids: Collection<Long>) {
+	suspend fun delete(ids: Collection<Long>): ReversibleHandle {
 		db.withTransaction {
 			for (id in ids) {
 				db.historyDao.delete(id)
 			}
 		}
-	}
-
-	suspend fun deleteReversible(ids: Collection<Long>): ReversibleHandle {
-		val entities = db.withTransaction {
-			val entities = db.historyDao.findAll(ids.toList()).filterNotNull()
-			for (id in ids) {
-				db.historyDao.delete(id)
-			}
-			entities
-		}
 		return ReversibleHandle {
-			db.historyDao.upsert(entities)
+			recover(ids)
 		}
 	}
 
@@ -128,4 +118,12 @@ class HistoryRepository(
 	suspend fun getPopularTags(limit: Int): List<MangaTag> {
 		return db.historyDao.findPopularTags(limit).map { x -> x.toMangaTag() }
 	}
+
+	private suspend fun recover(ids: Collection<Long>) {
+		db.withTransaction {
+			for (id in ids) {
+				db.historyDao.recover(id)
+			}
+		}
+	}
 }

app/src/main/java/org/koitharu/kotatsu/history/ui/HistoryListViewModel.kt

@@ -80,7 +80,7 @@ class HistoryListViewModel(
 			return
 		}
 		launchJob(Dispatchers.Default) {
-			val handle = repository.deleteReversible(ids) + ReversibleHandle {
+			val handle = repository.delete(ids) + ReversibleHandle {
 				shortcutsRepository.updateShortcuts()
 			}
 			shortcutsRepository.updateShortcuts()

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

@@ -304,4 +304,6 @@
 	<string name="detect_reader_mode">Autodetect reader mode</string>
 	<string name="detect_reader_mode_summary">Automatically detect if manga is webtoon</string>
 	<string name="enter_email_text">Enter your email to continue</string>
+	<string name="removed_from_favourites">Removed from favourites</string>
+	<string name="removed_from_s">Removed from \"%s\"</string>
 </resources>