music: re-add music browsing

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

@@ -23,7 +23,6 @@ import android.content.Context
 import android.content.Intent
 import android.os.Bundle
 import android.os.IBinder
-import android.support.v4.media.MediaBrowserCompat
 import android.support.v4.media.MediaBrowserCompat.MediaItem
 import androidx.annotation.StringRes
 import androidx.core.app.NotificationChannelCompat
@@ -37,16 +36,16 @@ import org.oxycblt.auxio.music.service.MusicServiceFragment
 import org.oxycblt.auxio.playback.service.PlaybackServiceFragment
 
 @AndroidEntryPoint
-class AuxioService : MediaBrowserServiceCompat(), ForegroundListener {
+class AuxioService : MediaBrowserServiceCompat(), ForegroundListener, MusicServiceFragment.Invalidator {
-    @Inject lateinit var mediaSessionFragment: PlaybackServiceFragment
+    @Inject lateinit var playbackFragment: PlaybackServiceFragment
 
-    @Inject lateinit var indexingFragment: MusicServiceFragment
+    @Inject lateinit var musicFragment: MusicServiceFragment
 
     @SuppressLint("WrongConstant")
     override fun onCreate() {
         super.onCreate()
-        setSessionToken(mediaSessionFragment.attach(this))
+        sessionToken = playbackFragment.attach(this)
-        indexingFragment.attach(this)
+        musicFragment.attach(this, this)
     }
 
     override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
@@ -63,26 +62,31 @@ class AuxioService : MediaBrowserServiceCompat(), ForegroundListener {
 
     private fun onHandleForeground(intent: Intent?) {
         val startId = intent?.getIntExtra(INTENT_KEY_START_ID, -1) ?: -1
-        indexingFragment.start()
+        musicFragment.start()
-        mediaSessionFragment.start(startId)
+        playbackFragment.start(startId)
     }
 
     override fun onTaskRemoved(rootIntent: Intent?) {
         super.onTaskRemoved(rootIntent)
-        mediaSessionFragment.handleTaskRemoved()
+        playbackFragment.handleTaskRemoved()
     }
 
     override fun onDestroy() {
         super.onDestroy()
-        indexingFragment.release()
+        musicFragment.release()
-        mediaSessionFragment.release()
+        playbackFragment.release()
+        sessionToken = null
     }
 
     override fun onGetRoot(
         clientPackageName: String,
         clientUid: Int,
         rootHints: Bundle?
-    ): BrowserRoot? = null
+    ): BrowserRoot = musicFragment.getRoot()
+
+    override fun onLoadItem(itemId: String, result: Result<MediaItem>) {
+        musicFragment.getItem(itemId, result)
+    }
 
     override fun onLoadChildren(
         parentId: String,
@@ -93,13 +97,8 @@ class AuxioService : MediaBrowserServiceCompat(), ForegroundListener {
         parentId: String,
         result: Result<MutableList<MediaItem>>,
         options: Bundle
-    ) {
+    ) = musicFragment.getChildren(parentId, result)
-        super.onLoadChildren(parentId, result, options)
-    }
 
-    override fun onLoadItem(itemId: String, result: Result<MediaItem>) {
-        super.onLoadItem(itemId, result)
-    }
 
     override fun onSearch(
         query: String,
@@ -120,7 +119,7 @@ class AuxioService : MediaBrowserServiceCompat(), ForegroundListener {
     }
 
     override fun updateForeground(change: ForegroundListener.Change) {
-        val mediaNotification = mediaSessionFragment.notification
+        val mediaNotification = playbackFragment.notification
         if (mediaNotification != null) {
             if (change == ForegroundListener.Change.MEDIA_SESSION) {
                 startForeground(mediaNotification.code, mediaNotification.build())
@@ -128,7 +127,7 @@ class AuxioService : MediaBrowserServiceCompat(), ForegroundListener {
             // Nothing changed, but don't show anything music related since we can always
             // index during playback.
         } else {
-            indexingFragment.createNotification {
+            musicFragment.createNotification {
                 if (it != null) {
                     startForeground(it.code, it.build())
                     isForeground = true
@@ -140,6 +139,10 @@ class AuxioService : MediaBrowserServiceCompat(), ForegroundListener {
         }
     }
 
+    override fun invalidateMusic(mediaId: String) {
+        notifyChildrenChanged(mediaId)
+    }
+
     companion object {
         var isForeground = false
             private set

app/src/main/java/org/oxycblt/auxio/music/service/Indexer.kt

@@ -0,0 +1,146 @@
+/*
+ * Copyright (c) 2024 Auxio Project
+ * IndexerServiceFragment.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.service
+
+import android.content.Context
+import android.os.PowerManager
+import coil.ImageLoader
+import dagger.hilt.android.qualifiers.ApplicationContext
+import javax.inject.Inject
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
+import org.oxycblt.auxio.BuildConfig
+import org.oxycblt.auxio.ForegroundListener
+import org.oxycblt.auxio.ForegroundServiceNotification
+import org.oxycblt.auxio.music.IndexingState
+import org.oxycblt.auxio.music.MusicRepository
+import org.oxycblt.auxio.music.MusicSettings
+import org.oxycblt.auxio.playback.state.PlaybackStateManager
+import org.oxycblt.auxio.util.getSystemServiceCompat
+import org.oxycblt.auxio.util.logD
+
+class Indexer
+@Inject
+constructor(
+    @ApplicationContext override val workerContext: Context,
+    private val playbackManager: PlaybackStateManager,
+    private val musicRepository: MusicRepository,
+    private val musicSettings: MusicSettings,
+    private val imageLoader: ImageLoader
+) :
+    MusicRepository.IndexingWorker,
+    MusicRepository.IndexingListener,
+    MusicRepository.UpdateListener,
+    MusicSettings.Listener {
+    private val indexJob = Job()
+    private val indexScope = CoroutineScope(indexJob + Dispatchers.IO)
+    private var currentIndexJob: Job? = null
+    private var foregroundListener: ForegroundListener? = null
+    private val wakeLock =
+        workerContext
+            .getSystemServiceCompat(PowerManager::class)
+            .newWakeLock(
+                PowerManager.PARTIAL_WAKE_LOCK, BuildConfig.APPLICATION_ID + ":IndexingComponent")
+
+    fun attach(listener: ForegroundListener) {
+        foregroundListener = listener
+        musicSettings.registerListener(this)
+        musicRepository.addUpdateListener(this)
+        musicRepository.addIndexingListener(this)
+        musicRepository.registerWorker(this)
+    }
+
+    fun release() {
+        musicSettings.registerListener(this)
+        musicRepository.addIndexingListener(this)
+        musicRepository.addUpdateListener(this)
+        musicRepository.removeIndexingListener(this)
+        foregroundListener = null
+    }
+
+    override fun requestIndex(withCache: Boolean) {
+        logD("Starting new indexing job (previous=${currentIndexJob?.hashCode()})")
+        // Cancel the previous music loading job.
+        currentIndexJob?.cancel()
+        // Start a new music loading job on a co-routine.
+        currentIndexJob = musicRepository.index(this, withCache)
+    }
+
+    override val scope = indexScope
+
+    override fun onIndexingStateChanged() {
+        foregroundListener?.updateForeground(ForegroundListener.Change.INDEXER)
+        val state = musicRepository.indexingState
+        if (state is IndexingState.Indexing) {
+            wakeLock.acquireSafe()
+        } else {
+            wakeLock.releaseSafe()
+        }
+    }
+
+    override fun onMusicChanges(changes: MusicRepository.Changes) {
+        val deviceLibrary = musicRepository.deviceLibrary ?: return
+        logD("Music changed, updating shared objects")
+        // Wipe possibly-invalidated outdated covers
+        imageLoader.memoryCache?.clear()
+        // Clear invalid models from PlaybackStateManager. This is not connected
+        // to a listener as it is bad practice for a shared object to attach to
+        // the listener system of another.
+        playbackManager.toSavedState()?.let { savedState ->
+            playbackManager.applySavedState(
+                savedState.copy(
+                    heap =
+                        savedState.heap.map { song ->
+                            song?.let { deviceLibrary.findSong(it.uid) }
+                        }),
+                true)
+        }
+    }
+
+    override fun onIndexingSettingChanged() {
+        super.onIndexingSettingChanged()
+        musicRepository.requestIndex(true)
+    }
+
+    /** Utility to safely acquire a [PowerManager.WakeLock] without crashes/inefficiency. */
+    private fun PowerManager.WakeLock.acquireSafe() {
+        // Avoid unnecessary acquire calls.
+        if (!wakeLock.isHeld) {
+            logD("Acquiring wake lock")
+            // Time out after a minute, which is the average music loading time for a medium-sized
+            // library. If this runs out, we will re-request the lock, and if music loading is
+            // shorter than the timeout, it will be released early.
+            acquire(WAKELOCK_TIMEOUT_MS)
+        }
+    }
+
+    /** Utility to safely release a [PowerManager.WakeLock] without crashes/inefficiency. */
+    private fun PowerManager.WakeLock.releaseSafe() {
+        // Avoid unnecessary release calls.
+        if (wakeLock.isHeld) {
+            logD("Releasing wake lock")
+            release()
+        }
+    }
+
+    companion object {
+        const val WAKELOCK_TIMEOUT_MS = 60 * 1000L
+    }
+}

app/src/main/java/org/oxycblt/auxio/music/service/MediaItemTranslation.kt

@@ -19,16 +19,13 @@
 package org.oxycblt.auxio.music.service
 
 import android.content.Context
-import android.graphics.Bitmap
 import android.graphics.BitmapFactory
 import android.os.Bundle
 import android.support.v4.media.MediaBrowserCompat.MediaItem
 import android.support.v4.media.MediaDescriptionCompat
-import android.support.v4.media.MediaMetadataCompat
 import androidx.annotation.DrawableRes
 import androidx.annotation.StringRes
 import androidx.media.utils.MediaConstants
-import androidx.media3.common.MediaMetadata
 import org.oxycblt.auxio.BuildConfig
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.music.Album
@@ -40,8 +37,6 @@ import org.oxycblt.auxio.music.Playlist
 import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.music.resolveNames
 import org.oxycblt.auxio.util.getPlural
-import java.io.ByteArrayOutputStream
-import kotlin.math.ceil
 
 enum class Category(val id: String, @StringRes val nameRes: Int, @DrawableRes val bitmapRes: Int?) {
     ROOT("root", R.string.info_app_name, null),
@@ -109,9 +104,15 @@ sealed interface MediaSessionUID {
     }
 }
 
+typealias Sugar = Bundle.(Context) -> Unit
+
+fun header(@StringRes nameRes: Int): Sugar = {
+    putString(MediaConstants.DESCRIPTION_EXTRAS_KEY_CONTENT_STYLE_GROUP_TITLE, it.getString(nameRes))
+}
+
 fun Category.toMediaItem(context: Context): MediaItem {
     // TODO: Make custom overflow menu for compat
-    val style =
+    val extras =
         Bundle().apply {
             putInt(
                 MediaConstants.DESCRIPTION_EXTRAS_KEY_CONTENT_STYLE_SINGLE_ITEM,
@@ -121,32 +122,41 @@ fun Category.toMediaItem(context: Context): MediaItem {
     val description = MediaDescriptionCompat.Builder()
         .setMediaId(mediaSessionUID.toString())
         .setTitle(context.getString(nameRes))
+        .setExtras(extras)
     if (bitmapRes != null) {
         val bitmap = BitmapFactory.decodeResource(context.resources, bitmapRes)
         description.setIconBitmap(bitmap)
     }
     return MediaItem(description.build(), MediaItem.FLAG_BROWSABLE)
 }
-fun Song.toMediaItem(context: Context, parent: MusicParent?): MediaItem {
+
+fun Song.toMediaItem(context: Context, parent: MusicParent? = null, vararg sugar: Sugar): MediaItem {
+    val mediaSessionUID =
+        if (parent == null) {
+            MediaSessionUID.SingleItem(uid)
+        } else {
+            MediaSessionUID.ChildItem(parent.uid, uid)
+        }
+    val extras = Bundle().apply { sugar.forEach { this.it(context) } }
+    val description = MediaDescriptionCompat.Builder()
+        .setMediaId(mediaSessionUID.toString())
+        .setTitle(name.resolve(context))
+        .setSubtitle(artists.resolveNames(context))
+        .setDescription(album.name.resolve(context))
+        .setIconUri(album.cover.single.mediaStoreCoverUri)
+        .setMediaUri(uri)
+        .setExtras(extras)
+        .build()
+    return MediaItem(description, MediaItem.FLAG_PLAYABLE)
+}
+
+fun Album.toMediaItem(context: Context, parent: MusicParent? = null, vararg sugar: Sugar): MediaItem {
     val mediaSessionUID =
         if (parent == null) {
             MediaSessionUID.SingleItem(uid)
         } else {
             MediaSessionUID.ChildItem(parent.uid, uid)
         }
-    val description = MediaDescriptionCompat.Builder()
-        .setMediaId(mediaSessionUID.toString())
-        .setTitle(name.resolve(context))
-        .setSubtitle(artists.resolveNames(context))
-        .setDescription(album.name.resolve(context))
-        .setIconUri(album.cover.single.mediaStoreCoverUri)
-        .setMediaUri(uri)
-        .build()
-    return MediaItem(description, MediaItem.FLAG_PLAYABLE)
-}
-
-fun Album.toMediaItem(context: Context): MediaItem {
-    val mediaSessionUID = MediaSessionUID.SingleItem(uid)
     val description = MediaDescriptionCompat.Builder()
         .setMediaId(mediaSessionUID.toString())
         .setTitle(name.resolve(context))
@@ -156,7 +166,7 @@ fun Album.toMediaItem(context: Context): MediaItem {
     return MediaItem(description, MediaItem.FLAG_BROWSABLE)
 }
 
-fun Artist.toMediaItem(context: Context): MediaItem {
+fun Artist.toMediaItem(context: Context, vararg sugar: Sugar): MediaItem {
     val mediaSessionUID = MediaSessionUID.SingleItem(uid)
     val counts =
                 context.getString(
@@ -180,7 +190,7 @@ fun Artist.toMediaItem(context: Context): MediaItem {
     return MediaItem(description, MediaItem.FLAG_BROWSABLE)
 }
 
-fun Genre.toMediaItem(context: Context): MediaItem {
+fun Genre.toMediaItem(context: Context, vararg sugar: Sugar): MediaItem {
     val mediaSessionUID = MediaSessionUID.SingleItem(uid)
     val counts =
                 if (songs.isNotEmpty()) {
@@ -197,7 +207,7 @@ fun Genre.toMediaItem(context: Context): MediaItem {
     return MediaItem(description, MediaItem.FLAG_BROWSABLE)
 }
 
-fun Playlist.toMediaItem(context: Context): MediaItem {
+fun Playlist.toMediaItem(context: Context, vararg sugar: Sugar): MediaItem {
     val mediaSessionUID = MediaSessionUID.SingleItem(uid)
     val counts =
                 if (songs.isNotEmpty()) {

app/src/main/java/org/oxycblt/auxio/music/service/MusicBrowser.kt

@@ -45,100 +45,71 @@ import org.oxycblt.auxio.search.SearchEngine
 import javax.inject.Inject
 import kotlin.math.min
 
-class MediaItemBrowser
+class MusicBrowser
 @Inject
 constructor(
     @ApplicationContext private val context: Context,
     private val musicRepository: MusicRepository,
     private val listSettings: ListSettings
 ) : MusicRepository.UpdateListener {
-    private val browserJob = Job()
-    private val searchScope = CoroutineScope(browserJob + Dispatchers.Default)
-    private val searchSubscribers = mutableMapOf<String, String>()
-    private val searchResults = mutableMapOf<String, Deferred<SearchEngine.Items>>()
-    private var invalidator: Invalidator? = null
-
     interface Invalidator {
-        fun invalidate(ids: Map<String, Int>)
+        fun invalidateMusic(ids: Set<String>)
-
-        fun invalidate(controller: String, query: String, itemCount: Int)
     }
 
+    private var invalidator: Invalidator? = null
+
     fun attach(invalidator: Invalidator) {
         this.invalidator = invalidator
         musicRepository.addUpdateListener(this)
     }
 
     fun release() {
-        browserJob.cancel()
-        invalidator = null
         musicRepository.removeUpdateListener(this)
     }
 
     override fun onMusicChanges(changes: MusicRepository.Changes) {
         val deviceLibrary = musicRepository.deviceLibrary
-        var invalidateSearch = false
+        val invalidate = mutableSetOf<String>()
-        val invalidate = mutableMapOf<String, Int>()
         if (changes.deviceLibrary && deviceLibrary != null) {
-            MediaSessionUID.Category.DEVICE_MUSIC.forEach {
+            Category.DEVICE_MUSIC.forEach {
-                invalidate[it.toString()] = getCategorySize(it, musicRepository)
+                invalidate.add(MediaSessionUID.CategoryItem(it).toString())
             }
 
             deviceLibrary.albums.forEach {
                 val id = MediaSessionUID.SingleItem(it.uid).toString()
-                invalidate[id] = it.songs.size
+                invalidate.add(id)
             }
 
             deviceLibrary.artists.forEach {
                 val id = MediaSessionUID.SingleItem(it.uid).toString()
-                invalidate[id] = it.songs.size + it.explicitAlbums.size + it.implicitAlbums.size
+                invalidate.add(id)
             }
 
             deviceLibrary.genres.forEach {
                 val id = MediaSessionUID.SingleItem(it.uid).toString()
-                invalidate[id] = it.songs.size + it.artists.size
+                invalidate.add(id)
             }
-
-            invalidateSearch = true
         }
         val userLibrary = musicRepository.userLibrary
         if (changes.userLibrary && userLibrary != null) {
-            MediaSessionUID.Category.USER_MUSIC.forEach {
+            Category.USER_MUSIC.forEach {
-                invalidate[it.toString()] = getCategorySize(it, musicRepository)
+                invalidate.add(MediaSessionUID.CategoryItem(it).toString())
             }
             userLibrary.playlists.forEach {
                 val id = MediaSessionUID.SingleItem(it.uid).toString()
-                invalidate[id] = it.songs.size
+                invalidate.add(id)
             }
-            invalidateSearch = true
         }
 
         if (invalidate.isNotEmpty()) {
-            invalidator?.invalidate(invalidate)
+            invalidator?.invalidateMusic(invalidate)
-        }
-
-        if (invalidateSearch) {
-            for (entry in searchResults.entries) {
-                searchResults[entry.key]?.cancel()
-            }
-            searchResults.clear()
-
-            for (entry in searchSubscribers.entries) {
-                if (searchResults[entry.value] != null) {
-                    continue
-                }
-                searchResults[entry.value] = searchTo(entry.value)
         }
     }
-    }
-
-    val root: MediaItem
-        get() = MediaSessionUID.Category.ROOT.toMediaItem(context)
 
     fun getItem(mediaId: String): MediaItem? {
         val music =
             when (val uid = MediaSessionUID.fromString(mediaId)) {
-                is MediaSessionUID.Category -> return uid.toMediaItem(context)
+                is MediaSessionUID.CategoryItem -> return uid.category.toMediaItem(context)
                 is MediaSessionUID.SingleItem ->
                     musicRepository.find(uid.uid)?.let { musicRepository.find(it.uid) }
 
@@ -158,15 +129,14 @@ constructor(
         }
     }
 
-    fun getChildren(parentId: String, page: Int, pageSize: Int): List<MediaItem>? {
+    fun getChildren(parentId: String): List<MediaItem>? {
         val deviceLibrary = musicRepository.deviceLibrary
         val userLibrary = musicRepository.userLibrary
         if (deviceLibrary == null || userLibrary == null) {
             return listOf()
         }
 
-        val items = getMediaItemList(parentId, deviceLibrary, userLibrary) ?: return null
+        return getMediaItemList(parentId, deviceLibrary, userLibrary)
-        return items.paginate(page, pageSize)
     }
 
     private fun getMediaItemList(
@@ -175,32 +145,34 @@ constructor(
         userLibrary: UserLibrary
     ): List<MediaItem>? {
         return when (val mediaSessionUID = MediaSessionUID.fromString(id)) {
-            is MediaSessionUID.Category -> {
+            is MediaSessionUID.CategoryItem -> {
-                when (mediaSessionUID) {
+                when (mediaSessionUID.category) {
-                    MediaSessionUID.Category.ROOT ->
+                    Category.ROOT ->
-                        MediaSessionUID.Category.IMPORTANT.map { it.toMediaItem(context) }
+                        Category.IMPORTANT.map { it.toMediaItem(context) }
 
-                    MediaSessionUID.Category.SONGS ->
+                    Category.MORE -> TODO()
+
+                    Category.SONGS ->
                         listSettings.songSort.songs(deviceLibrary.songs).map {
                             it.toMediaItem(context, null)
                         }
 
-                    MediaSessionUID.Category.ALBUMS ->
+                    Category.ALBUMS ->
                         listSettings.albumSort.albums(deviceLibrary.albums).map {
                             it.toMediaItem(context)
                         }
 
-                    MediaSessionUID.Category.ARTISTS ->
+                    Category.ARTISTS ->
                         listSettings.artistSort.artists(deviceLibrary.artists).map {
                             it.toMediaItem(context)
                         }
 
-                    MediaSessionUID.Category.GENRES ->
+                    Category.GENRES ->
                         listSettings.genreSort.genres(deviceLibrary.genres).map {
                             it.toMediaItem(context)
                         }
 
-                    MediaSessionUID.Category.PLAYLISTS ->
+                    Category.PLAYLISTS ->
                         userLibrary.playlists.map { it.toMediaItem(context) }
                 }
             }
@@ -223,25 +195,25 @@ constructor(
         return when (val item = musicRepository.find(uid)) {
             is Album -> {
                 val songs = listSettings.albumSongSort.songs(item.songs)
-                songs.map { it.toMediaItem(context, item).withHeader(R.string.lbl_songs) }
+                songs.map { it.toMediaItem(context, item, header(R.string.lbl_songs))}
             }
 
             is Artist -> {
                 val albums = ARTIST_ALBUMS_SORT.albums(item.explicitAlbums + item.implicitAlbums)
                 val songs = listSettings.artistSongSort.songs(item.songs)
-                albums.map { it.toMediaItem(context).withHeader(R.string.lbl_albums) } +
+                albums.map { it.toMediaItem(context, null, header(R.string.lbl_songs)) } +
-                        songs.map { it.toMediaItem(context, item).withHeader(R.string.lbl_songs) }
+                        songs.map { it.toMediaItem(context, item, header(R.string.lbl_songs)) }
             }
 
             is Genre -> {
                 val artists = GENRE_ARTISTS_SORT.artists(item.artists)
                 val songs = listSettings.genreSongSort.songs(item.songs)
-                artists.map { it.toMediaItem(context).withHeader(R.string.lbl_artists) } +
+                artists.map { it.toMediaItem(context, header(R.string.lbl_songs)) } +
-                        songs.map { it.toMediaItem(context, null).withHeader(R.string.lbl_songs) }
+                        songs.map { it.toMediaItem(context, null, header(R.string.lbl_songs)) }
             }
 
             is Playlist -> {
-                item.songs.map { it.toMediaItem(context, item).withHeader(R.string.lbl_songs) }
+                item.songs.map { it.toMediaItem(context, null, header(R.string.lbl_songs)) }
             }
 
             is Song,
@@ -249,121 +221,91 @@ constructor(
         }
     }
 
-    private fun MediaItem.withHeader(@StringRes res: Int): MediaItem {
+//    suspend fun prepareSearch(query: String, controller: String) {
-        val oldExtras = mediaMetadata.extras ?: Bundle()
+//        searchSubscribers[controller] = query
-        val newExtras =
+//        val existing = searchResults[query]
-            Bundle(oldExtras).apply {
+//        if (existing == null) {
-                putString(
+//            val new = searchTo(query)
-                    MediaConstants.DESCRIPTION_EXTRAS_KEY_CONTENT_STYLE_GROUP_TITLE,
+//            searchResults[query] = new
-                    context.getString(res)
+//            new.await()
-                )
+//        } else {
-            }
+//            val items = existing.await()
-        return buildUpon()
+//            invalidator?.invalidate(controller, query, items.count())
-            .setMediaMetadata(mediaMetadata.buildUpon().setExtras(newExtras).build())
+//        }
-            .build()
+//    }
-    }
+//
-
+//    suspend fun getSearchResult(
-    private fun getCategorySize(
+//        query: String,
-        category: MediaSessionUID.Category,
+//        page: Int,
-        musicRepository: MusicRepository
+//        pageSize: Int,
-    ): Int {
+//    ): List<MediaItem>? {
-        val deviceLibrary = musicRepository.deviceLibrary ?: return 0
+//        val deferred = searchResults[query] ?: searchTo(query).also { searchResults[query] = it }
-        val userLibrary = musicRepository.userLibrary ?: return 0
+//        return deferred.await().concat().paginate(page, pageSize)
-        return when (category) {
+//    }
-            MediaSessionUID.Category.ROOT -> MediaSessionUID.Category.IMPORTANT.size
+//
-            MediaSessionUID.Category.SONGS -> deviceLibrary.songs.size
+//    private fun SearchEngine.Items.concat(): MutableList<MediaItem> {
-            MediaSessionUID.Category.ALBUMS -> deviceLibrary.albums.size
+//        val music = mutableListOf<MediaItem>()
-            MediaSessionUID.Category.ARTISTS -> deviceLibrary.artists.size
+//        if (songs != null) {
-            MediaSessionUID.Category.GENRES -> deviceLibrary.genres.size
+//            music.addAll(songs.map { it.toMediaItem(context, null) })
-            MediaSessionUID.Category.PLAYLISTS -> userLibrary.playlists.size
+//        }
-        }
+//        if (albums != null) {
-    }
+//            music.addAll(albums.map { it.toMediaItem(context) })
-
+//        }
-    suspend fun prepareSearch(query: String, controller: ControllerInfo) {
+//        if (artists != null) {
-        searchSubscribers[controller] = query
+//            music.addAll(artists.map { it.toMediaItem(context) })
-        val existing = searchResults[query]
+//        }
-        if (existing == null) {
+//        if (genres != null) {
-            val new = searchTo(query)
+//            music.addAll(genres.map { it.toMediaItem(context) })
-            searchResults[query] = new
+//        }
-            new.await()
+//        if (playlists != null) {
-        } else {
+//            music.addAll(playlists.map { it.toMediaItem(context) })
-            val items = existing.await()
+//        }
-            invalidator?.invalidate(controller, query, items.count())
+//        return music
-        }
+//    }
-    }
+//
-
+//    private fun SearchEngine.Items.count(): Int {
-    suspend fun getSearchResult(
+//        var count = 0
-        query: String,
+//        if (songs != null) {
-        page: Int,
+//            count += songs.size
-        pageSize: Int,
+//        }
-    ): List<MediaItem>? {
+//        if (albums != null) {
-        val deferred = searchResults[query] ?: searchTo(query).also { searchResults[query] = it }
+//            count += albums.size
-        return deferred.await().concat().paginate(page, pageSize)
+//        }
-    }
+//        if (artists != null) {
-
+//            count += artists.size
-    private fun SearchEngine.Items.concat(): MutableList<MediaItem> {
+//        }
-        val music = mutableListOf<MediaItem>()
+//        if (genres != null) {
-        if (songs != null) {
+//            count += genres.size
-            music.addAll(songs.map { it.toMediaItem(context, null) })
+//        }
-        }
+//        if (playlists != null) {
-        if (albums != null) {
+//            count += playlists.size
-            music.addAll(albums.map { it.toMediaItem(context) })
+//        }
-        }
+//        return count
-        if (artists != null) {
+//    }
-            music.addAll(artists.map { it.toMediaItem(context) })
+//
-        }
+//    private fun searchTo(query: String) =
-        if (genres != null) {
+//        searchScope.async {
-            music.addAll(genres.map { it.toMediaItem(context) })
+//            if (query.isEmpty()) {
-        }
+//                return@async SearchEngine.Items()
-        if (playlists != null) {
+//            }
-            music.addAll(playlists.map { it.toMediaItem(context) })
+//            val deviceLibrary = musicRepository.deviceLibrary ?: return@async SearchEngine.Items()
-        }
+//            val userLibrary = musicRepository.userLibrary ?: return@async SearchEngine.Items()
-        return music
+//            val items =
-    }
+//                SearchEngine.Items(
-
+//                    deviceLibrary.songs,
-    private fun SearchEngine.Items.count(): Int {
+//                    deviceLibrary.albums,
-        var count = 0
+//                    deviceLibrary.artists,
-        if (songs != null) {
+//                    deviceLibrary.genres,
-            count += songs.size
+//                    userLibrary.playlists
-        }
+//                )
-        if (albums != null) {
+//            val results = searchEngine.search(items, query)
-            count += albums.size
+//            for (entry in searchSubscribers.entries) {
-        }
+//                if (entry.value == query) {
-        if (artists != null) {
+//                    invalidator?.invalidate(entry.key, query, results.count())
-            count += artists.size
+//                }
-        }
+//            }
-        if (genres != null) {
+//            results
-            count += genres.size
+//        }
-        }
-        if (playlists != null) {
-            count += playlists.size
-        }
-        return count
-    }
-
-    private fun searchTo(query: String) =
-        searchScope.async {
-            if (query.isEmpty()) {
-                return@async SearchEngine.Items()
-            }
-            val deviceLibrary = musicRepository.deviceLibrary ?: return@async SearchEngine.Items()
-            val userLibrary = musicRepository.userLibrary ?: return@async SearchEngine.Items()
-            val items =
-                SearchEngine.Items(
-                    deviceLibrary.songs,
-                    deviceLibrary.albums,
-                    deviceLibrary.artists,
-                    deviceLibrary.genres,
-                    userLibrary.playlists
-                )
-            val results = searchEngine.search(items, query)
-            for (entry in searchSubscribers.entries) {
-                if (entry.value == query) {
-                    invalidator?.invalidate(entry.key, query, results.count())
-                }
-            }
-            results
-        }
 
     private fun List<MediaItem>.paginate(page: Int, pageSize: Int): List<MediaItem>? {
         if (page == Int.MAX_VALUE) {

app/src/main/java/org/oxycblt/auxio/music/service/MusicServiceFragment.kt

@@ -19,7 +19,12 @@
 package org.oxycblt.auxio.music.service
 
 import android.content.Context
+import android.os.Bundle
 import android.os.PowerManager
+import androidx.media.MediaBrowserServiceCompat.BrowserRoot
+import androidx.media.MediaBrowserServiceCompat
+import androidx.media.utils.MediaConstants
+import android.support.v4.media.MediaBrowserCompat.MediaItem
 import coil.ImageLoader
 import dagger.hilt.android.qualifiers.ApplicationContext
 import javax.inject.Inject
@@ -35,54 +40,65 @@ import org.oxycblt.auxio.music.MusicSettings
 import org.oxycblt.auxio.playback.state.PlaybackStateManager
 import org.oxycblt.auxio.util.getSystemServiceCompat
 import org.oxycblt.auxio.util.logD
+import org.oxycblt.auxio.util.logW
 
 class MusicServiceFragment
 @Inject
 constructor(
-    @ApplicationContext override val workerContext: Context,
+    @ApplicationContext context: Context,
-    private val playbackManager: PlaybackStateManager,
+    private val indexer: Indexer,
+    private val browser: MusicBrowser,
     private val musicRepository: MusicRepository,
     private val musicSettings: MusicSettings,
     private val contentObserver: SystemContentObserver,
-    private val imageLoader: ImageLoader
+) : MusicBrowser.Invalidator, MusicSettings.Listener {
-) :
+    private val indexingNotification = IndexingNotification(context)
-    MusicRepository.IndexingWorker,
+    private val observingNotification = ObservingNotification(context)
-    MusicRepository.IndexingListener,
+    private var invalidator: Invalidator? = null
-    MusicRepository.UpdateListener,
-    MusicSettings.Listener {
-    private val indexJob = Job()
-    private val indexScope = CoroutineScope(indexJob + Dispatchers.IO)
-    private var currentIndexJob: Job? = null
-    private val indexingNotification = IndexingNotification(workerContext)
-    private val observingNotification = ObservingNotification(workerContext)
     private var foregroundListener: ForegroundListener? = null
-    private val wakeLock =
-        workerContext
-            .getSystemServiceCompat(PowerManager::class)
-            .newWakeLock(
-                PowerManager.PARTIAL_WAKE_LOCK, BuildConfig.APPLICATION_ID + ":IndexingComponent")
 
-    fun attach(listener: ForegroundListener) {
+    interface Invalidator {
-        foregroundListener = listener
+        fun invalidateMusic(mediaId: String)
-        musicSettings.registerListener(this)
+    }
-        musicRepository.addUpdateListener(this)
+
-        musicRepository.addIndexingListener(this)
+    fun attach(foregroundListener: ForegroundListener, invalidator: Invalidator) {
-        musicRepository.registerWorker(this)
+        this.invalidator = invalidator
+        indexer.attach(foregroundListener)
+        browser.attach(this)
         contentObserver.attach()
+        musicSettings.registerListener(this)
     }
 
     fun release() {
+        musicSettings.unregisterListener(this)
         contentObserver.release()
-        musicSettings.registerListener(this)
+        browser.release()
-        musicRepository.addIndexingListener(this)
+        indexer.release()
-        musicRepository.addUpdateListener(this)
+        invalidator = null
-        musicRepository.removeIndexingListener(this)
+    }
-        foregroundListener = null
+
+
+    override fun invalidateMusic(ids: Set<String>) {
+        ids.forEach { mediaId ->
+            requireNotNull(invalidator) { "Invalidator not available" }.invalidateMusic(mediaId)
+        }
+    }
+
+    override fun onObservingChanged() {
+        super.onObservingChanged()
+        // Make sure we don't override the service state with the observing
+        // notification if we were actively loading when the automatic rescanning
+        // setting changed. In such a case, the state will still be updated when
+        // the music loading process ends.
+        if (musicRepository.indexingState == null) {
+            logD("Not loading, updating idle session")
+            foregroundListener?.updateForeground(ForegroundListener.Change.INDEXER)
+        }
     }
 
     fun start() {
         if (musicRepository.indexingState == null) {
-            requestIndex(true)
+            musicRepository.requestIndex(true)
         }
     }
 
@@ -108,84 +124,24 @@ constructor(
         }
     }
 
-    override fun requestIndex(withCache: Boolean) {
+    fun getRoot() = BrowserRoot(Category.ROOT.id, null)
-        logD("Starting new indexing job (previous=${currentIndexJob?.hashCode()})")
-        // Cancel the previous music loading job.
-        currentIndexJob?.cancel()
-        // Start a new music loading job on a co-routine.
-        currentIndexJob = musicRepository.index(this, withCache)
-    }
 
-    override val scope = indexScope
+    fun getItem(mediaId: String, result: MediaBrowserServiceCompat.Result<MediaItem>) =
+        result.dispatch { browser.getItem(mediaId) }
 
-    override fun onIndexingStateChanged() {
+    fun getChildren(mediaId: String, result: MediaBrowserServiceCompat.Result<MutableList<MediaItem>>) =
-        foregroundListener?.updateForeground(ForegroundListener.Change.INDEXER)
+        result.dispatch { browser.getChildren(mediaId)?.toMutableList() }
-        val state = musicRepository.indexingState
-        if (state is IndexingState.Indexing) {
-            wakeLock.acquireSafe()
-        } else {
-            wakeLock.releaseSafe()
-        }
-    }
 
-    override fun onMusicChanges(changes: MusicRepository.Changes) {
+    private fun <T> MediaBrowserServiceCompat.Result<T>.dispatch(body: () -> T?) {
-        val deviceLibrary = musicRepository.deviceLibrary ?: return
+        try {
-        logD("Music changed, updating shared objects")
+            val result = body()
-        // Wipe possibly-invalidated outdated covers
+            if (result == null) {
-        imageLoader.memoryCache?.clear()
+                logW("Result is null")
-        // Clear invalid models from PlaybackStateManager. This is not connected
-        // to a listener as it is bad practice for a shared object to attach to
-        // the listener system of another.
-        playbackManager.toSavedState()?.let { savedState ->
-            playbackManager.applySavedState(
-                savedState.copy(
-                    heap =
-                        savedState.heap.map { song ->
-                            song?.let { deviceLibrary.findSong(it.uid) }
-                        }),
-                true)
             }
+            sendResult(result)
+        } catch (e: Exception) {
+            logD("Error while dispatching: $e")
+            sendResult(null)
         }
-
-    override fun onIndexingSettingChanged() {
-        super.onIndexingSettingChanged()
-        musicRepository.requestIndex(true)
-    }
-
-    override fun onObservingChanged() {
-        super.onObservingChanged()
-        // Make sure we don't override the service state with the observing
-        // notification if we were actively loading when the automatic rescanning
-        // setting changed. In such a case, the state will still be updated when
-        // the music loading process ends.
-        if (currentIndexJob == null) {
-            logD("Not loading, updating idle session")
-            foregroundListener?.updateForeground(ForegroundListener.Change.INDEXER)
-        }
-    }
-
-    /** Utility to safely acquire a [PowerManager.WakeLock] without crashes/inefficiency. */
-    private fun PowerManager.WakeLock.acquireSafe() {
-        // Avoid unnecessary acquire calls.
-        if (!wakeLock.isHeld) {
-            logD("Acquiring wake lock")
-            // Time out after a minute, which is the average music loading time for a medium-sized
-            // library. If this runs out, we will re-request the lock, and if music loading is
-            // shorter than the timeout, it will be released early.
-            acquire(WAKELOCK_TIMEOUT_MS)
-        }
-    }
-
-    /** Utility to safely release a [PowerManager.WakeLock] without crashes/inefficiency. */
-    private fun PowerManager.WakeLock.releaseSafe() {
-        // Avoid unnecessary release calls.
-        if (wakeLock.isHeld) {
-            logD("Releasing wake lock")
-            release()
-        }
-    }
-
-    companion object {
-        const val WAKELOCK_TIMEOUT_MS = 60 * 1000L
     }
 }