Always update 'All tracks' playlist on rescan

Tracks that are explicitly removed by the user won't be added back, a string set preference is used to store the track ids deleted from 'All tracks' playlist. Of course, there are other ways to do this (with or without db modification) but using a preference turned out to be the simplest solution.

app/src/main/kotlin/com/simplemobiletools/musicplayer/adapters/TracksAdapter.kt

@@ -24,6 +24,7 @@ import com.simplemobiletools.musicplayer.R
 import com.simplemobiletools.musicplayer.activities.SimpleActivity
 import com.simplemobiletools.musicplayer.dialogs.EditDialog
 import com.simplemobiletools.musicplayer.extensions.*
+import com.simplemobiletools.musicplayer.helpers.ALL_TRACKS_PLAYLIST_ID
 import com.simplemobiletools.musicplayer.helpers.PLAYER_SORT_BY_CUSTOM
 import com.simplemobiletools.musicplayer.helpers.TagHelper
 import com.simplemobiletools.musicplayer.inlines.indexOfFirstOrNull
@@ -151,6 +152,15 @@ class TracksAdapter(
             }
 
             activity.tracksDAO.removeTracks(selectedTracks)
+            // this is to make sure these tracks aren't automatically re-added to the 'All tracks' playlist on rescan
+            val removedTrackIds = selectedTracks.filter { it.playListId == ALL_TRACKS_PLAYLIST_ID }.map { it.mediaStoreId.toString() }
+            if (removedTrackIds.isNotEmpty()) {
+                val config = activity.config
+                config.tracksRemovedFromAllTracksPlaylist = config.tracksRemovedFromAllTracksPlaylist.apply {
+                    addAll(removedTrackIds)
+                }
+            }
+
             EventBus.getDefault().post(Events.PlaylistsUpdated())
             activity.runOnUiThread {
                 positions.sortDescending()
@@ -234,12 +244,12 @@ class TracksAdapter(
                 .transform(CenterCrop(), RoundedCorners(cornerRadius))
 
             context.getTrackCoverArt(track) { coverArt ->
-               activity.runOnUiThread {
-                   Glide.with(activity)
-                       .load(coverArt)
-                       .apply(options)
-                       .into(findViewById(R.id.track_image))
-               }
+                activity.runOnUiThread {
+                    Glide.with(activity)
+                        .load(coverArt)
+                        .apply(options)
+                        .into(findViewById(R.id.track_image))
+                }
             }
 
             track_image.beVisible()

app/src/main/kotlin/com/simplemobiletools/musicplayer/helpers/Config.kt

@@ -109,6 +109,12 @@ class Config(context: Context) : BaseConfig(context) {
         get() = prefs.getBoolean(WAS_ALL_TRACKS_PLAYLIST_CREATED, false)
         set(wasAllTracksPlaylistCreated) = prefs.edit().putBoolean(WAS_ALL_TRACKS_PLAYLIST_CREATED, wasAllTracksPlaylistCreated).apply()
 
+    var tracksRemovedFromAllTracksPlaylist: MutableSet<String>
+        get() = prefs.getStringSet(TRACKS_REMOVED_FROM_ALL_TRACKS_PLAYLIST, HashSet())!!
+        set(tracksRemovedFromAllTracksPlaylist) = prefs.edit().remove(TRACKS_REMOVED_FROM_ALL_TRACKS_PLAYLIST)
+            .putStringSet(TRACKS_REMOVED_FROM_ALL_TRACKS_PLAYLIST, tracksRemovedFromAllTracksPlaylist)
+            .apply()
+
     var showTabs: Int
         get() = prefs.getInt(SHOW_TABS, allTabsMask)
         set(showTabs) = prefs.edit().putInt(SHOW_TABS, showTabs).apply()

app/src/main/kotlin/com/simplemobiletools/musicplayer/helpers/Constants.kt

@@ -64,6 +64,7 @@ const val PLAYBACK_SPEED_PROGRESS = "PLAYBACK_SPEED_PROGRESS"
 const val WERE_TRACK_FOLDERS_ADDED = "were_track_folders_added"
 const val SHOW_TABS = "show_tabs"
 const val WAS_ALL_TRACKS_PLAYLIST_CREATED = "was_all_tracks_playlist_created"
+const val TRACKS_REMOVED_FROM_ALL_TRACKS_PLAYLIST = "tracks_removed_from_all_tracks_playlist"
 const val LAST_EXPORT_PATH = "last_export_path"
 const val EXCLUDED_FOLDERS = "excluded_folders"
 const val SORT_PLAYLIST_PREFIX = "sort_playlist_"

app/src/main/kotlin/com/simplemobiletools/musicplayer/helpers/SimpleMediaScanner.kt

@@ -264,12 +264,16 @@ class SimpleMediaScanner(private val context: Application) {
             val allTracksLabel = context.resources.getString(R.string.all_tracks)
             val playlist = Playlist(ALL_TRACKS_PLAYLIST_ID, allTracksLabel)
             context.playlistDAO.insert(playlist)
-            tracks.forEach {
-                it.playListId = ALL_TRACKS_PLAYLIST_ID
-            }
-            RoomHelper(context).insertTracksWithPlaylist(tracks)
             config.wasAllTracksPlaylistCreated = true
         }
+
+        // avoid re-adding tracks that have been explicitly removed from 'All tracks' playlist
+        val excludedFolders = config.excludedFolders
+        val tracksRemovedFromAllTracks = config.tracksRemovedFromAllTracksPlaylist.map { it.toLong() }
+        val tracksWithPlaylist = tracks
+            .filter { it.mediaStoreId !in tracksRemovedFromAllTracks && it.playListId == 0  && it.path.getParentPath() !in excludedFolders }
+            .onEach { it.playListId = ALL_TRACKS_PLAYLIST_ID }
+        RoomHelper(context).insertTracksWithPlaylist(tracksWithPlaylist as ArrayList<Track>)
     }
 
     private fun getAllAudioFiles(): ArrayList<Track> {