Fix list items reorder

app/src/main/kotlin/org/koitharu/kotatsu/settings/sources/adapter/SourceConfigAdapter.kt

@@ -2,14 +2,14 @@ package org.koitharu.kotatsu.settings.sources.adapter
 
 import androidx.lifecycle.LifecycleOwner
 import coil.ImageLoader
-import org.koitharu.kotatsu.core.ui.BaseListAdapter
+import org.koitharu.kotatsu.core.ui.ReorderableListAdapter
 import org.koitharu.kotatsu.settings.sources.model.SourceConfigItem
 
 class SourceConfigAdapter(
 	listener: SourceConfigListener,
 	coil: ImageLoader,
 	lifecycleOwner: LifecycleOwner,
-) : BaseListAdapter<SourceConfigItem>() {
+) : ReorderableListAdapter<SourceConfigItem>() {
 
 	init {
 		with(delegatesManager) {

app/src/main/kotlin/org/koitharu/kotatsu/settings/sources/manage/SourcesManageFragment.kt

@@ -54,6 +54,7 @@ class SourcesManageFragment :
 	lateinit var shortcutManager: AppShortcutManager
 
 	private var reorderHelper: ItemTouchHelper? = null
+	private var sourcesAdapter: SourceConfigAdapter? = null
 	private val viewModel by viewModels<SourcesManageViewModel>()
 
 	override val recyclerView: RecyclerView
@@ -69,7 +70,7 @@ class SourcesManageFragment :
 		savedInstanceState: Bundle?,
 	) {
 		super.onViewBindingCreated(binding, savedInstanceState)
-		val sourcesAdapter = SourceConfigAdapter(this, coil, viewLifecycleOwner)
+		sourcesAdapter = SourceConfigAdapter(this, coil, viewLifecycleOwner)
 		with(binding.recyclerView) {
 			setHasFixedSize(true)
 			adapter = sourcesAdapter
@@ -77,7 +78,7 @@ class SourcesManageFragment :
 				it.attachToRecyclerView(this)
 			}
 		}
-		viewModel.content.observe(viewLifecycleOwner, sourcesAdapter)
+		viewModel.content.observe(viewLifecycleOwner, checkNotNull(sourcesAdapter))
 		viewModel.onActionDone.observeEvent(
 			viewLifecycleOwner,
 			ReversibleActionObserver(binding.recyclerView),
@@ -91,6 +92,7 @@ class SourcesManageFragment :
 	}
 
 	override fun onDestroyView() {
+		sourcesAdapter = null
 		reorderHelper = null
 		super.onDestroyView()
 	}
@@ -204,7 +206,7 @@ class SourcesManageFragment :
 			y: Int,
 		) {
 			super.onMoved(recyclerView, viewHolder, fromPos, target, toPos, x, y)
-			viewModel.reorderSources(fromPos, toPos)
+			sourcesAdapter?.reorderItems(fromPos, toPos)
 		}
 
 		override fun canDropOver(
@@ -248,5 +250,10 @@ class SourcesManageFragment :
 		}
 
 		override fun isLongPressDragEnabled() = true
+
+		override fun clearView(recyclerView: RecyclerView, viewHolder: RecyclerView.ViewHolder) {
+			super.clearView(recyclerView, viewHolder)
+			viewModel.saveSourcesOrder(sourcesAdapter?.items ?: return)
+		}
 	}
 }

app/src/main/kotlin/org/koitharu/kotatsu/settings/sources/manage/SourcesManageViewModel.kt

@@ -4,8 +4,6 @@ import dagger.hilt.android.lifecycle.HiltViewModel
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.Job
 import kotlinx.coroutines.cancelAndJoin
-import kotlinx.coroutines.delay
-import kotlinx.coroutines.yield
 import org.koitharu.kotatsu.R
 import org.koitharu.kotatsu.core.db.MangaDatabase
 import org.koitharu.kotatsu.core.db.removeObserverAsync
@@ -43,17 +41,19 @@ class SourcesManageViewModel @Inject constructor(
 		database.invalidationTracker.removeObserverAsync(listProducer)
 	}
 
-	fun reorderSources(oldPos: Int, newPos: Int) {
-		val snapshot = content.value.toMutableList()
-		if ((snapshot[oldPos] as? SourceConfigItem.SourceItem)?.isDraggable != true) {
-			return
+	fun saveSourcesOrder(snapshot: List<SourceConfigItem>) {
+		val prevJob = commitJob
+		commitJob = launchJob(Dispatchers.Default) {
+			prevJob?.cancelAndJoin()
+			val newSourcesList = snapshot.mapNotNull { x ->
+				if (x is SourceConfigItem.SourceItem && x.isDraggable) {
+					x.source
+				} else {
+					null
+				}
+			}
+			repository.setPositions(newSourcesList)
 		}
-		if ((snapshot[newPos] as? SourceConfigItem.SourceItem)?.isDraggable != true) {
-			return
-		}
-		snapshot.move(oldPos, newPos)
-		content.value = snapshot
-		commit(snapshot)
 	}
 
 	fun canReorder(oldPos: Int, newPos: Int): Boolean {
@@ -72,28 +72,31 @@ class SourcesManageViewModel @Inject constructor(
 	}
 
 	fun bringToTop(source: MangaSource) {
-		var oldPos = -1
-		var newPos = -1
 		val snapshot = content.value
-		for ((i, x) in snapshot.withIndex()) {
-			if (x !is SourceConfigItem.SourceItem) {
-				continue
+		launchJob(Dispatchers.Default) {
+			var oldPos = -1
+			var newPos = -1
+			for ((i, x) in snapshot.withIndex()) {
+				if (x !is SourceConfigItem.SourceItem) {
+					continue
+				}
+				if (newPos == -1) {
+					newPos = i
+				}
+				if (x.source == source) {
+					oldPos = i
+					break
+				}
 			}
-			if (newPos == -1) {
-				newPos = i
+			@Suppress("KotlinConstantConditions")
+			if (oldPos != -1 && newPos != -1) {
+				reorderSources(oldPos, newPos)
+				val revert = ReversibleAction(R.string.moved_to_top) {
+					reorderSources(newPos, oldPos)
+				}
+				commitJob?.join()
+				onActionDone.call(revert)
 			}
-			if (x.source == source) {
-				oldPos = i
-				break
-			}
-		}
-		@Suppress("KotlinConstantConditions")
-		if (oldPos != -1 && newPos != -1) {
-			reorderSources(oldPos, newPos)
-			val revert = ReversibleAction(R.string.moved_to_top) {
-				reorderSources(newPos, oldPos)
-			}
-			onActionDone.call(revert)
 		}
 	}
 
@@ -113,20 +116,15 @@ class SourcesManageViewModel @Inject constructor(
 		}
 	}
 
-	private fun commit(snapshot: List<SourceConfigItem>) {
-		val prevJob = commitJob
-		commitJob = launchJob {
-			prevJob?.cancelAndJoin()
-			delay(500)
-			val newSourcesList = snapshot.mapNotNull { x ->
-				if (x is SourceConfigItem.SourceItem && x.isDraggable) {
-					x.source
-				} else {
-					null
-				}
-			}
-			repository.setPositions(newSourcesList)
-			yield()
+	private fun reorderSources(oldPos: Int, newPos: Int) {
+		val snapshot = content.value.toMutableList()
+		if ((snapshot[oldPos] as? SourceConfigItem.SourceItem)?.isDraggable != true) {
+			return
 		}
+		if ((snapshot[newPos] as? SourceConfigItem.SourceItem)?.isDraggable != true) {
+			return
+		}
+		snapshot.move(oldPos, newPos)
+		saveSourcesOrder(snapshot)
 	}
 }