Option to undo removing from favourites

app/build.gradle

@@ -102,7 +102,7 @@ dependencies {
 	implementation 'com.hannesdorfmann:adapterdelegates4-kotlin-dsl-viewbinding:4.3.2'
 
 	implementation 'io.insert-koin:koin-android:3.2.0'
-	implementation 'io.coil-kt:coil-base:2.0.0-rc03'
+	implementation 'io.coil-kt:coil-base:2.0.0'
 	implementation 'com.davemorrissey.labs:subsampling-scale-image-view-androidx:3.10.0'
 	implementation 'com.github.solkin:disk-lru-cache:1.4'
 

app/src/main/java/org/koitharu/kotatsu/base/domain/ReversibleHandle.kt

@@ -0,0 +1,19 @@
+package org.koitharu.kotatsu.base.domain
+
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
+import org.koitharu.kotatsu.utils.ext.processLifecycleScope
+
+fun interface ReversibleHandle {
+
+	suspend fun reverse()
+}
+
+fun ReversibleHandle.reverseAsync() = processLifecycleScope.launch(Dispatchers.Default) {
+	reverse()
+}
+
+operator fun ReversibleHandle.plus(other: ReversibleHandle) = ReversibleHandle {
+	this.reverse()
+	other.reverse()
+}

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

@@ -15,6 +15,10 @@ abstract class HistoryDao {
 	@Query("SELECT * FROM history ORDER BY updated_at DESC LIMIT :limit OFFSET :offset")
 	abstract suspend fun findAll(offset: Int, limit: Int): List<HistoryWithManga>
 
+	@Transaction
+	@Query("SELECT * FROM history WHERE manga_id IN (:ids)")
+	abstract suspend fun findAll(ids: Collection<Long>): List<HistoryEntity?>
+
 	@Transaction
 	@Query("SELECT * FROM history ORDER BY updated_at DESC")
 	abstract fun observeAll(): Flow<List<HistoryWithManga>>
@@ -69,4 +73,13 @@ abstract class HistoryDao {
 			true
 		} else false
 	}
+
+	@Transaction
+	open suspend fun upsert(entities: Iterable<HistoryEntity>) {
+		for (e in entities) {
+			if (update(e) == 0) {
+				insert(e)
+			}
+		}
+	}
 }

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

@@ -4,6 +4,7 @@ import androidx.room.withTransaction
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.distinctUntilChanged
 import kotlinx.coroutines.flow.map
+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.MangaHistory
@@ -100,6 +101,19 @@ class HistoryRepository(
 		}
 	}
 
+	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)
+		}
+	}
+
 	/**
 	 * Try to replace one manga with another one
 	 * Useful for replacing saved manga on deleting it with remove source

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

@@ -7,8 +7,11 @@ import android.view.MenuItem
 import android.view.View
 import androidx.appcompat.view.ActionMode
 import com.google.android.material.dialog.MaterialAlertDialogBuilder
+import com.google.android.material.snackbar.Snackbar
 import org.koin.androidx.viewmodel.ext.android.viewModel
 import org.koitharu.kotatsu.R
+import org.koitharu.kotatsu.base.domain.ReversibleHandle
+import org.koitharu.kotatsu.base.domain.reverseAsync
 import org.koitharu.kotatsu.list.ui.MangaListFragment
 import org.koitharu.kotatsu.parsers.model.MangaSource
 
@@ -22,6 +25,7 @@ class HistoryListFragment : MangaListFragment() {
 		viewModel.isGroupingEnabled.observe(viewLifecycleOwner) {
 			activity?.invalidateOptionsMenu()
 		}
+		viewModel.onItemsRemoved.observe(viewLifecycleOwner, ::onItemsRemoved)
 	}
 
 	override fun onScrolledToEnd() = Unit
@@ -80,6 +84,12 @@ class HistoryListFragment : MangaListFragment() {
 		}
 	}
 
+	private fun onItemsRemoved(reversibleHandle: ReversibleHandle) {
+		Snackbar.make(binding.recyclerView, R.string.removed_from_history, Snackbar.LENGTH_LONG)
+			.setAction(R.string.undo) { reversibleHandle.reverseAsync() }
+			.show()
+	}
+
 	companion object {
 
 		fun newInstance() = HistoryListFragment()

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

@@ -7,6 +7,8 @@ import kotlinx.coroutines.flow.catch
 import kotlinx.coroutines.flow.combine
 import kotlinx.coroutines.flow.onEach
 import org.koitharu.kotatsu.R
+import org.koitharu.kotatsu.base.domain.ReversibleHandle
+import org.koitharu.kotatsu.base.domain.plus
 import org.koitharu.kotatsu.core.os.ShortcutsRepository
 import org.koitharu.kotatsu.core.prefs.AppSettings
 import org.koitharu.kotatsu.core.prefs.ListMode
@@ -17,6 +19,7 @@ import org.koitharu.kotatsu.history.domain.MangaWithHistory
 import org.koitharu.kotatsu.list.ui.MangaListViewModel
 import org.koitharu.kotatsu.list.ui.model.*
 import org.koitharu.kotatsu.tracker.domain.TrackingRepository
+import org.koitharu.kotatsu.utils.SingleLiveEvent
 import org.koitharu.kotatsu.utils.ext.asLiveDataDistinct
 import org.koitharu.kotatsu.utils.ext.daysDiff
 import org.koitharu.kotatsu.utils.ext.onFirst
@@ -31,6 +34,7 @@ class HistoryListViewModel(
 ) : MangaListViewModel(settings) {
 
 	val isGroupingEnabled = MutableLiveData<Boolean>()
+	val onItemsRemoved = SingleLiveEvent<ReversibleHandle>()
 
 	private val historyGrouping = settings.observeAsFlow(AppSettings.KEY_HISTORY_GROUPING) { historyGrouping }
 		.onEach { isGroupingEnabled.postValue(it) }
@@ -72,10 +76,13 @@ class HistoryListViewModel(
 		if (ids.isEmpty()) {
 			return
 		}
-		launchJob {
+		launchJob(Dispatchers.Default) {
-			repository.delete(ids)
+			val handle = repository.deleteReversible(ids) + ReversibleHandle {
 				shortcutsRepository.updateShortcuts()
 			}
+			shortcutsRepository.updateShortcuts()
+			onItemsRemoved.postCall(handle)
+		}
 	}
 
 	fun setGrouping(isGroupingEnabled: Boolean) {

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

@@ -293,4 +293,6 @@
 	<string name="bookmarks">Bookmarks</string>
 	<string name="bookmark_removed">Bookmark removed</string>
 	<string name="bookmark_added">Bookmark added</string>
+	<string name="undo">Undo</string>
+	<string name="removed_from_history">Removed from history</string>
 </resources>