music: add playlist deletion dialog

Add a dialog that allows the user to confirm playlist deletion, instead
of it happening immediately.

app/src/main/java/org/oxycblt/auxio/MainFragment.kt

@@ -41,6 +41,7 @@ import org.oxycblt.auxio.databinding.FragmentMainBinding
 import org.oxycblt.auxio.list.selection.SelectionViewModel
 import org.oxycblt.auxio.music.Music
 import org.oxycblt.auxio.music.MusicViewModel
+import org.oxycblt.auxio.music.Playlist
 import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.navigation.MainNavigationAction
 import org.oxycblt.auxio.navigation.NavigationViewModel
@@ -136,6 +137,7 @@ class MainFragment :
         collect(navModel.exploreArtistNavigationItem.flow, ::handleArtistNavigationPicker)
         collect(musicModel.newPlaylistSongs.flow, ::handleNewPlaylist)
         collect(musicModel.songsToAdd.flow, ::handleAddToPlaylist)
+        collect(musicModel.playlistToDelete.flow, ::handleDeletePlaylist)
         collectImmediately(playbackModel.song, ::updateSong)
         collect(playbackModel.artistPickerSong.flow, ::handlePlaybackArtistPicker)
         collect(playbackModel.genrePickerSong.flow, ::handlePlaybackGenrePicker)
@@ -322,6 +324,13 @@ class MainFragment :
         }
     }
 
+    private fun handleDeletePlaylist(playlist: Playlist?) {
+        if (playlist != null) {
+            findNavController()
+                .navigateSafe(MainFragmentDirections.actionDeletePlaylist(playlist.uid))
+            musicModel.playlistToDelete.consume()
+        }
+    }
     private fun handlePlaybackArtistPicker(song: Song?) {
         if (song != null) {
             navModel.mainNavigateTo(

app/src/main/java/org/oxycblt/auxio/detail/AlbumDetailFragment.kt

@@ -99,7 +99,7 @@ class AlbumDetailFragment :
 
         // -- VIEWMODEL SETUP ---
         // DetailViewModel handles most initialization from the navigation argument.
-        detailModel.setAlbumUid(args.albumUid)
+        detailModel.setAlbum(args.albumUid)
         collectImmediately(detailModel.currentAlbum, ::updateAlbum)
         collectImmediately(detailModel.albumList, ::updateList)
         collectImmediately(

app/src/main/java/org/oxycblt/auxio/detail/ArtistDetailFragment.kt

@@ -98,7 +98,7 @@ class ArtistDetailFragment :
 
         // --- VIEWMODEL SETUP ---
         // DetailViewModel handles most initialization from the navigation argument.
-        detailModel.setArtistUid(args.artistUid)
+        detailModel.setArtist(args.artistUid)
         collectImmediately(detailModel.currentArtist, ::updateArtist)
         collectImmediately(detailModel.artistList, ::updateList)
         collectImmediately(

app/src/main/java/org/oxycblt/auxio/detail/DetailViewModel.kt

@@ -224,47 +224,47 @@ constructor(
     }
 
     /**
-     * Set a new [currentSong] from it's [Music.UID]. If the [Music.UID] differs, [currentSong] and
+     * Set a new [currentSong] from it's [Music.UID]. [currentSong] and [songAudioProperties] will
-     * [songAudioProperties] will be updated to align with the new [Song].
+     * be updated to align with the new [Song].
      *
      * @param uid The UID of the [Song] to load. Must be valid.
      */
-    fun setSongUid(uid: Music.UID) {
+    fun setSong(uid: Music.UID) {
         logD("Opening Song [uid: $uid]")
         _currentSong.value = musicRepository.deviceLibrary?.findSong(uid)?.also(::refreshAudioInfo)
     }
 
     /**
-     * Set a new [currentAlbum] from it's [Music.UID]. If the [Music.UID] differs, [currentAlbum]
+     * Set a new [currentAlbum] from it's [Music.UID]. [currentAlbum] and [albumList] will be
-     * and [albumList] will be updated to align with the new [Album].
+     * updated to align with the new [Album].
      *
      * @param uid The [Music.UID] of the [Album] to update [currentAlbum] to. Must be valid.
      */
-    fun setAlbumUid(uid: Music.UID) {
+    fun setAlbum(uid: Music.UID) {
         logD("Opening Album [uid: $uid]")
         _currentAlbum.value =
             musicRepository.deviceLibrary?.findAlbum(uid)?.also(::refreshAlbumList)
     }
 
     /**
-     * Set a new [currentArtist] from it's [Music.UID]. If the [Music.UID] differs, [currentArtist]
+     * Set a new [currentArtist] from it's [Music.UID]. [currentArtist] and [artistList] will be
-     * and [artistList] will be updated to align with the new [Artist].
+     * updated to align with the new [Artist].
      *
      * @param uid The [Music.UID] of the [Artist] to update [currentArtist] to. Must be valid.
      */
-    fun setArtistUid(uid: Music.UID) {
+    fun setArtist(uid: Music.UID) {
         logD("Opening Artist [uid: $uid]")
         _currentArtist.value =
             musicRepository.deviceLibrary?.findArtist(uid)?.also(::refreshArtistList)
     }
 
     /**
-     * Set a new [currentGenre] from it's [Music.UID]. If the [Music.UID] differs, [currentGenre]
+     * Set a new [currentGenre] from it's [Music.UID]. [currentGenre] and [genreList] will be
-     * and [genreList] will be updated to align with the new album.
+     * updated to align with the new album.
      *
      * @param uid The [Music.UID] of the [Genre] to update [currentGenre] to. Must be valid.
      */
-    fun setGenreUid(uid: Music.UID) {
+    fun setGenre(uid: Music.UID) {
         logD("Opening Genre [uid: $uid]")
         _currentGenre.value =
             musicRepository.deviceLibrary?.findGenre(uid)?.also(::refreshGenreList)

app/src/main/java/org/oxycblt/auxio/detail/GenreDetailFragment.kt

@@ -91,7 +91,7 @@ class GenreDetailFragment :
 
         // --- VIEWMODEL SETUP ---
         // DetailViewModel handles most initialization from the navigation argument.
-        detailModel.setGenreUid(args.genreUid)
+        detailModel.setGenre(args.genreUid)
         collectImmediately(detailModel.currentGenre, ::updatePlaylist)
         collectImmediately(detailModel.genreList, ::updateList)
         collectImmediately(

app/src/main/java/org/oxycblt/auxio/detail/SongDetailDialog.kt

@@ -67,7 +67,7 @@ class SongDetailDialog : ViewBindingDialogFragment<DialogSongDetailBinding>() {
         super.onBindingCreated(binding, savedInstanceState)
         binding.detailProperties.adapter = detailAdapter
         // DetailViewModel handles most initialization from the navigation argument.
-        detailModel.setSongUid(args.songUid)
+        detailModel.setSong(args.songUid)
         collectImmediately(detailModel.currentSong, detailModel.songAudioProperties, ::updateSong)
     }
 

app/src/main/java/org/oxycblt/auxio/music/MusicViewModel.kt

@@ -48,13 +48,18 @@ constructor(
     val statistics: StateFlow<Statistics?>
         get() = _statistics
 
-    private val _newPlaylistSongs = MutableEvent<List<Song>?>()
+    private val _newPlaylistSongs = MutableEvent<List<Song>>()
     /** Flag for opening a dialog to create a playlist of the given [Song]s. */
-    val newPlaylistSongs: Event<List<Song>?> = _newPlaylistSongs
+    val newPlaylistSongs: Event<List<Song>> = _newPlaylistSongs
 
-    private val _songsToAdd = MutableEvent<List<Song>?>()
+    private val _songsToAdd = MutableEvent<List<Song>>()
     /** Flag for opening a dialog to add the given [Song]s to a playlist. */
-    val songsToAdd: Event<List<Song>?> = _songsToAdd
+    val songsToAdd: Event<List<Song>> = _songsToAdd
+
+    private val _playlistToDelete = MutableEvent<Playlist>()
+    /** Flag for opening a dialog to confirm deletion of the given [Playlist]. */
+    val playlistToDelete: Event<Playlist>
+        get() = _playlistToDelete
 
     init {
         musicRepository.addUpdateListener(this)
@@ -110,11 +115,15 @@ constructor(
      * Delete a [Playlist].
      *
      * @param playlist The playlist to delete.
-     *
+     * @param rude Whether to immediately delete the playlist or prompt the user first. This should
-     * TODO: Prompt the user before deleting.
+     *   be false at almost all times.
      */
-    fun deletePlaylist(playlist: Playlist) {
+    fun deletePlaylist(playlist: Playlist, rude: Boolean = false) {
-        musicRepository.deletePlaylist(playlist)
+        if (rude) {
+            musicRepository.deletePlaylist(playlist)
+        } else {
+            _playlistToDelete.put(playlist)
+        }
     }
 
     /**

app/src/main/java/org/oxycblt/auxio/music/picker/AddToPlaylistDialog.kt

@@ -71,8 +71,8 @@ class AddToPlaylistDialog :
         }
 
         // --- VIEWMODEL SETUP ---
-        pickerModel.setPendingSongs(args.songUids)
+        pickerModel.setSongsToAdd(args.songUids)
-        collectImmediately(pickerModel.currentPendingSongs, ::updatePendingSongs)
+        collectImmediately(pickerModel.currentSongsToAdd, ::updatePendingSongs)
         collectImmediately(pickerModel.playlistChoices, ::updatePlaylistChoices)
     }
 
@@ -82,13 +82,13 @@ class AddToPlaylistDialog :
     }
 
     override fun onClick(item: PlaylistChoice, viewHolder: RecyclerView.ViewHolder) {
-        musicModel.addToPlaylist(pickerModel.currentPendingSongs.value ?: return, item.playlist)
+        musicModel.addToPlaylist(pickerModel.currentSongsToAdd.value ?: return, item.playlist)
         requireContext().showToast(R.string.lng_playlist_added)
         findNavController().navigateUp()
     }
 
     override fun onNewPlaylist() {
-        musicModel.createPlaylist(songs = pickerModel.currentPendingSongs.value ?: return)
+        musicModel.createPlaylist(songs = pickerModel.currentSongsToAdd.value ?: return)
     }
 
     private fun updatePendingSongs(songs: List<Song>?) {

app/src/main/java/org/oxycblt/auxio/music/picker/DeletePlaylistDialog.kt

@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 2023 Auxio Project
+ * DeletePlaylistDialog.kt is part of Auxio.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+ 
+package org.oxycblt.auxio.music.picker
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import androidx.appcompat.app.AlertDialog
+import androidx.fragment.app.activityViewModels
+import androidx.fragment.app.viewModels
+import androidx.navigation.fragment.findNavController
+import androidx.navigation.fragment.navArgs
+import dagger.hilt.android.AndroidEntryPoint
+import org.oxycblt.auxio.R
+import org.oxycblt.auxio.databinding.DialogDeletePlaylistBinding
+import org.oxycblt.auxio.music.MusicViewModel
+import org.oxycblt.auxio.music.Playlist
+import org.oxycblt.auxio.ui.ViewBindingDialogFragment
+import org.oxycblt.auxio.util.collectImmediately
+import org.oxycblt.auxio.util.unlikelyToBeNull
+
+/**
+ * A [ViewBindingDialogFragment] that asks the user to confirm the deletion of a [Playlist].
+ * @author Alexander Capehart (OxygenCobalt)
+ */
+@AndroidEntryPoint
+class DeletePlaylistDialog : ViewBindingDialogFragment<DialogDeletePlaylistBinding>() {
+    private val pickerModel: PlaylistPickerViewModel by viewModels()
+    private val musicModel: MusicViewModel by activityViewModels()
+    // Information about what playlist to name for is initially within the navigation arguments
+    // as UIDs, as that is the only safe way to parcel playlist information.
+    private val args: DeletePlaylistDialogArgs by navArgs()
+
+    override fun onConfigDialog(builder: AlertDialog.Builder) {
+        builder
+            .setTitle(R.string.lbl_confirm_delete_playlist)
+            .setPositiveButton(R.string.lbl_delete) { _, _ ->
+                // Now we can delete the playlist for-real this time.
+                musicModel.deletePlaylist(
+                    unlikelyToBeNull(pickerModel.currentPlaylistToDelete.value), rude = true)
+            }
+            .setNegativeButton(R.string.lbl_cancel, null)
+    }
+
+    override fun onCreateBinding(inflater: LayoutInflater) =
+        DialogDeletePlaylistBinding.inflate(inflater)
+
+    override fun onBindingCreated(
+        binding: DialogDeletePlaylistBinding,
+        savedInstanceState: Bundle?
+    ) {
+        super.onBindingCreated(binding, savedInstanceState)
+
+        // --- VIEWMODEL SETUP ---
+        pickerModel.setPlaylistToDelete(args.playlistUid)
+        collectImmediately(pickerModel.currentPlaylistToDelete, ::updatePlaylistToDelete)
+    }
+
+    private fun updatePlaylistToDelete(playlist: Playlist?) {
+        if (playlist == null) {
+            // Playlist does not exist anymore, leave
+            findNavController().navigateUp()
+            return
+        }
+
+        requireBinding().deletionInfo.text =
+            getString(R.string.fmt_deletion_info, playlist.name.resolve(requireContext()))
+    }
+}

app/src/main/java/org/oxycblt/auxio/music/picker/PlaylistPickerViewModel.kt

@@ -48,14 +48,18 @@ class PlaylistPickerViewModel @Inject constructor(private val musicRepository: M
     val chosenName: StateFlow<ChosenName>
         get() = _chosenName
 
-    private val _currentPendingSongs = MutableStateFlow<List<Song>?>(null)
+    private val _currentSongsToAdd = MutableStateFlow<List<Song>?>(null)
-    val currentPendingSongs: StateFlow<List<Song>?>
+    val currentSongsToAdd: StateFlow<List<Song>?>
-        get() = _currentPendingSongs
+        get() = _currentSongsToAdd
 
     private val _playlistChoices = MutableStateFlow<List<PlaylistChoice>>(listOf())
     val playlistChoices: StateFlow<List<PlaylistChoice>>
         get() = _playlistChoices
 
+    private val _currentPlaylistToDelete = MutableStateFlow<Playlist?>(null)
+    val currentPlaylistToDelete: StateFlow<Playlist?>
+        get() = _currentPlaylistToDelete
+
     init {
         musicRepository.addUpdateListener(this)
     }
@@ -70,8 +74,8 @@ class PlaylistPickerViewModel @Inject constructor(private val musicRepository: M
                         pendingPlaylist.preferredName,
                         pendingPlaylist.songs.mapNotNull { deviceLibrary.findSong(it.uid) })
                 }
-            _currentPendingSongs.value =
+            _currentSongsToAdd.value =
-                _currentPendingSongs.value?.let { pendingSongs ->
+                _currentSongsToAdd.value?.let { pendingSongs ->
                     pendingSongs
                         .mapNotNull { deviceLibrary.findSong(it.uid) }
                         .ifEmpty { null }
@@ -88,7 +92,7 @@ class PlaylistPickerViewModel @Inject constructor(private val musicRepository: M
                     // Nothing to do.
                 }
             }
-            refreshChoicesWith = refreshChoicesWith ?: _currentPendingSongs.value
+            refreshChoicesWith = refreshChoicesWith ?: _currentSongsToAdd.value
         }
 
         refreshChoicesWith?.let(::refreshPlaylistChoices)
@@ -99,7 +103,7 @@ class PlaylistPickerViewModel @Inject constructor(private val musicRepository: M
     }
 
     /**
-     * Update the current [PendingPlaylist]. Will do nothing if already equal.
+     * Set a new [currentPendingPlaylist] from a new batch of pending [Song] [Music.UID]s.
      *
      * @param context [Context] required to generate a playlist name.
      * @param songUids The [Music.UID]s of songs to be present in the playlist.
@@ -121,7 +125,7 @@ class PlaylistPickerViewModel @Inject constructor(private val musicRepository: M
     }
 
     /**
-     * Update the current [ChosenName] based on new user input.
+     * Update the current [chosenName] based on new user input.
      *
      * @param name The new user-inputted name, or null if not present.
      */
@@ -143,16 +147,14 @@ class PlaylistPickerViewModel @Inject constructor(private val musicRepository: M
     }
 
     /**
-     * Update the current [Song]s that to show playlist add choices for. Will do nothing if already
+     * Set a new [currentSongsToAdd] from a new batch of pending [Song] [Music.UID]s.
-     * equal.
      *
      * @param songUids The [Music.UID]s of songs to add to a playlist.
      */
-    fun setPendingSongs(songUids: Array<Music.UID>) {
+    fun setSongsToAdd(songUids: Array<Music.UID>) {
-        if (currentPendingSongs.value?.map { it.uid } == songUids) return
         val deviceLibrary = musicRepository.deviceLibrary ?: return
         val songs = songUids.mapNotNull(deviceLibrary::findSong)
-        _currentPendingSongs.value = songs
+        _currentSongsToAdd.value = songs
         refreshPlaylistChoices(songs)
     }
 
@@ -164,6 +166,15 @@ class PlaylistPickerViewModel @Inject constructor(private val musicRepository: M
                 PlaylistChoice(it, songs.all(songSet::contains))
             }
     }
+
+    /**
+     * Set a new [currentPendingPlaylist] from a new [Playlist] [Music.UID].
+     *
+     * @param playlistUid The [Music.UID] of the [Playlist] to delete.
+     */
+    fun setPlaylistToDelete(playlistUid: Music.UID) {
+        _currentPlaylistToDelete.value = musicRepository.userLibrary?.findPlaylist(playlistUid)
+    }
 }
 
 /**

app/src/main/res/layout/dialog_delete_playlist.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+<TextView xmlns:android="http://schemas.android.com/apk/res/android"
+    android:id="@+id/deletion_info"
+    android:layout_width="match_parent"
+    android:paddingTop="@dimen/spacing_medium"
+    android:paddingEnd="@dimen/spacing_large"
+    android:paddingStart="@dimen/spacing_large"
+    android:layout_height="match_parent"
+    android:textAppearance="@style/TextAppearance.Auxio.BodyLarge"
+    xmlns:tools="http://schemas.android.com/tools"
+    tools:text="Delete Playlist 16? This cannot be undone."/>

app/src/main/res/navigation/nav_main.xml

@@ -23,6 +23,9 @@
         <action
             android:id="@+id/action_add_to_playlist"
             app:destination="@id/add_to_playlist_dialog" />
+        <action
+            android:id="@+id/action_delete_playlist"
+            app:destination="@id/delete_playlist_dialog" />
         <action
             android:id="@+id/action_pick_navigation_artist"
             app:destination="@id/navigate_to_artist_dialog" />
@@ -67,6 +70,16 @@
             app:destination="@id/new_playlist_dialog" />
     </dialog>
 
+    <dialog
+        android:id="@+id/delete_playlist_dialog"
+        android:name="org.oxycblt.auxio.music.picker.DeletePlaylistDialog"
+        android:label="delete_playlist_dialog"
+        tools:layout="@layout/dialog_playlist_name">
+        <argument
+            android:name="playlistUid"
+            app:argType="org.oxycblt.auxio.music.Music$UID" />
+    </dialog>
+
     <dialog
         android:id="@+id/navigate_to_artist_dialog"
         android:name="org.oxycblt.auxio.navigation.picker.NavigateToArtistDialog"

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

@@ -80,6 +80,7 @@
     <string name="lbl_playlists">Playlists</string>
     <string name="lbl_new_playlist">New playlist</string>
     <string name="lbl_delete">Delete</string>
+    <string name="lbl_confirm_delete_playlist">Delete playlist?</string>
 
     <!-- Search for music -->
     <string name="lbl_search">Search</string>
@@ -395,6 +396,7 @@
     <string name="fmt_sample_rate">%d Hz</string>
 
     <string name="fmt_indexing">Loading your music library… (%1$d/%2$d)</string>
+    <string name="fmt_deletion_info">Delete %s? This cannot be undone.</string>
 
     <string name="fmt_lib_song_count">Songs loaded: %d</string>
     <string name="fmt_lib_album_count">Albums loaded: %d</string>