Random sort. Fixes.

fermata/src/auto/java/me/aap/fermata/auto/MainCarActivity.java

@@ -100,7 +100,8 @@ public FutureSupplier<Intent> startActivityForResult(Intent intent) {
 		return failed(new UnsupportedOperationException());
 	}
 
-	public void checkPermissions(String... perms) {
+	public FutureSupplier<int[]> checkPermissions(String... perms) {
+		return failed(new UnsupportedOperationException());
 	}
 
 	@Override

fermata/src/main/java/me/aap/fermata/media/engine/MediaEngineManager.java

@@ -125,7 +125,7 @@ public MediaEngine createAnotherEngine(@NonNull MediaEngine current, Listener li
 
 	private boolean isProviderAvailable(String providerClass) {
 		try {
-			Class.forName(providerClass);
+			Class.forName(providerClass).newInstance();
 			return true;
 		} catch (Throwable ex) {
 			return false;

fermata/src/main/java/me/aap/fermata/media/engine/MetadataRetriever.java

@@ -97,16 +97,20 @@ private MetadataBuilder load(PlayableItem item) {
 		if (meta != null) return meta;
 
 		MetaBuilder mb = new MetaBuilder();
-		MediaEngineProvider vlcPlayer = mgr.vlcPlayer;
+		MediaEngineProvider mp = mgr.mediaPlayer;
+		MediaEngineProvider vlc = mgr.vlcPlayer;
 		VirtualResource file = item.getFile();
 
 		if (file.isLocalFile() && file.getName().endsWith(".flac")) {
 			// VLC does not extract images from flac, thus prefer Android extractor for local files
-			mgr.mediaPlayer.getMediaMetadata(mb, item);
-		} else if ((vlcPlayer != null) && (!"content".equals(item.getLocation().getScheme()))) {
-			if (!vlcPlayer.getMediaMetadata(mb, item)) mgr.mediaPlayer.getMediaMetadata(mb, item);
+			if (!mp.getMediaMetadata(mb, item) && (vlc != null)) {
+				// Seems flac is not supported, trying VLC
+				vlc.getMediaMetadata(mb, item);
+			}
+		} else if (vlc != null) {
+			if (!vlc.getMediaMetadata(mb, item)) mp.getMediaMetadata(mb, item);
 		} else {
-			mgr.mediaPlayer.getMediaMetadata(mb, item);
+			mp.getMediaMetadata(mb, item);
 		}
 
 		try {

fermata/src/main/java/me/aap/fermata/media/lib/BrowsableItemBase.java

@@ -143,10 +143,10 @@ private FutureSupplier<Void> loadMetadata(List<Item> children) {
 	}
 
 	protected FutureSupplier<String> buildTitle(int seqNum, BrowsableItemPrefs parentPrefs) {
+		String name = getName();
 		try (SharedTextBuilder tb = SharedTextBuilder.get()) {
 			if (seqNum != 0) tb.append(seqNum).append(". ");
-			tb.append(getName());
-			return completed(tb.toString());
+			return completed(tb.append(name).toString());
 		}
 	}
 
@@ -173,14 +173,8 @@ protected String buildSubtitle(List<Item> children) {
 	public FutureSupplier<Iterator<PlayableItem>> getShuffleIterator() {
 		if ((shuffle == null) || (shuffle.isDone() && !shuffle.get(null).hasNext())) {
 			shuffle = getPlayableChildren(false, false, Integer.MAX_VALUE).map(list -> {
-				Random rnd = ThreadLocalRandom.current();
 				List<PlayableItem> l = new ArrayList<>(list);
-
-				for (int i = 0, s = l.size(); i < s; i++) {
-					int next = rnd.nextInt(s - i);
-					Collections.swap(l, i, next);
-				}
-
+				shuffle(l);
 				Iterator<PlayableItem> it = l.iterator();
 				shuffle = completed(it);
 				return it;
@@ -199,37 +193,43 @@ protected String getChildrenIdPattern() {
 	public FutureSupplier<Void> updateTitles() {
 		FutureSupplier<List<Item>> list = CHILDREN.get(this);
 		if (list == null) return super.updateTitles();
-		return list.then(children -> Async.forEach(Item::updateTitles, children)).then(v -> super.updateTitles());
+		return list.then(children -> {
+			for (Item i : children) {
+				i.updateTitles();
+			}
+			return super.updateTitles();
+		});
 	}
 
 	@NonNull
 	@Override
-	public FutureSupplier<Void> refresh() {
-		updateTitles();
-		CHILDREN.set(this, null);
-		return updateTitles();
+	public FutureSupplier<Void> updateSorting() {
+		FutureSupplier<List<Item>> list = CHILDREN.get(this);
+		if (list == null) return completedVoid();
+		return updateTitles().onSuccess(v -> CHILDREN.compareAndSet(this, list, null));
 	}
 
 	@NonNull
 	@Override
-	public FutureSupplier<Void> rescan() {
+	public FutureSupplier<Void> refresh() {
 		FutureSupplier<List<Item>> list = CHILDREN.get(this);
-		String pattern = getChildrenIdPattern();
-		if (pattern != null) getLib().getMetadataRetriever().clearMetadata(pattern);
-		if (list == null) return refresh();
-		CHILDREN.set(this, null);
-		return list.then(children -> Async.forEach(i -> {
-			if (i instanceof ItemBase) ((ItemBase) i).reset();
-			return completedVoid();
-		}, children)).then(v -> super.updateTitles());
+		if (list == null) return super.updateTitles();
+		return list.then(children -> {
+			for (Item i : children) {
+				if (i instanceof ItemBase) ((ItemBase) i).reset();
+				else i.updateTitles();
+			}
+			CHILDREN.compareAndSet(this, list, null);
+			return super.updateTitles();
+		});
 	}
 
 	@NonNull
 	@Override
-	public FutureSupplier<Void> updateSorting() {
-		FutureSupplier<List<Item>> list = CHILDREN.get(this);
-		if (list == null) return completedVoid();
-		return list.map(ArrayList::new).thenReplaceOrClear(CHILDREN, this, list).then(v -> updateTitles());
+	public FutureSupplier<Void> rescan() {
+		String pattern = getChildrenIdPattern();
+		if (pattern != null) getLib().getMetadataRetriever().clearMetadata(pattern);
+		return refresh();
 	}
 
 	void setChildren(List<Item> c) {
@@ -263,6 +263,9 @@ private FutureSupplier<List<Item>> sortChildren(List<Item> list) {
 					setSeqNum(sorted);
 					return completed(sorted);
 				});
+			case BrowsableItemPrefs.SORT_BY_RND:
+				shuffle(sorted);
+				break;
 		}
 
 		setSeqNum(sorted);
@@ -275,6 +278,15 @@ private void setSeqNum(SortedItems sorted) {
 		}
 	}
 
+	private void shuffle(List<?> l) {
+		Random rnd = ThreadLocalRandom.current();
+
+		for (int i = 0, s = l.size(); i < s; i++) {
+			int next = rnd.nextInt(s - i);
+			Collections.swap(l, i, next);
+		}
+	}
+
 	private int compareByFile(Item i1, Item i2, boolean desc) {
 		if (i1 instanceof BrowsableItem) {
 			if (i2 instanceof BrowsableItem) {

fermata/src/main/java/me/aap/fermata/media/lib/CueItem.java

@@ -14,6 +14,8 @@
 import me.aap.fermata.media.lib.MediaLib.BrowsableItem;
 import me.aap.fermata.media.lib.MediaLib.Item;
 import me.aap.fermata.util.Utils;
+import me.aap.utils.app.App;
+import me.aap.utils.async.FutureRef;
 import me.aap.utils.async.FutureSupplier;
 import me.aap.utils.log.Log;
 import me.aap.utils.text.SharedTextBuilder;
@@ -23,21 +25,28 @@
 
 import static java.nio.charset.StandardCharsets.UTF_8;
 import static me.aap.fermata.BuildConfig.DEBUG;
-import static me.aap.utils.async.Completed.completed;
 
 /**
  * @author Andrey Pavlenko
  */
 class CueItem extends BrowsableItemBase {
 	public static final String SCHEME = "cue";
-	private final String name;
-	private final String subtitle;
-	private final List<CueTrackItem> tracks;
+	private final FutureRef<Data> data = new FutureRef<Data>() {
+		@Override
+		protected FutureSupplier<Data> create() {
+			return App.get().execute(CueItem.this::parse);
+		}
+	};
 
-	private CueItem(String id, BrowsableItem parent, VirtualFolder dir, VirtualFile cueFile) {
+	private CueItem(String id, BrowsableItem parent, VirtualFile cueFile) {
 		super(id, parent, cueFile);
+	}
 
-		Context ctx = parent.getLib().getContext();
+	private Data parse() {
+		String id = getId();
+		VirtualFile cueFile = (VirtualFile) getFile();
+		VirtualFolder dir = cueFile.getParent().getOrThrow();
+		Context ctx = getLib().getContext();
 		List<CueTrackItem> tracks = new ArrayList<>();
 		VirtualResource file = null;
 		String fileName = null;
@@ -122,12 +131,12 @@ private CueItem(String id, BrowsableItem parent, VirtualFolder dir, VirtualFile
 			Log.e(ex, "Failed to parse cue file: ", getFile());
 		}
 
-		this.tracks = tracks;
-		this.name = (albumTitle != null) ? albumTitle : cueFile.getName();
-		this.subtitle = ctx.getResources().getString(R.string.browsable_subtitle, tracks.size());
+		String name = (albumTitle != null) ? albumTitle : cueFile.getName();
+		String subtitle = ctx.getResources().getString(R.string.browsable_subtitle, tracks.size());
+		return new Data(name, subtitle, tracks);
 	}
 
-	static CueItem create(String id, BrowsableItem parent, VirtualFolder dir, VirtualFile cueFile,
+	static CueItem create(String id, BrowsableItem parent, VirtualFile cueFile,
 												DefaultMediaLib lib) {
 		synchronized (lib.cacheLock()) {
 			Item i = lib.getFromCache(id);
@@ -138,7 +147,7 @@ static CueItem create(String id, BrowsableItem parent, VirtualFolder dir, Virtua
 				if (DEBUG && !cueFile.equals(c.getFile())) throw new AssertionError();
 				return c;
 			} else {
-				return new CueItem(id, parent, dir, cueFile);
+				return new CueItem(id, parent, cueFile);
 			}
 		}
 	}
@@ -154,7 +163,7 @@ static FutureSupplier<Item> create(DefaultMediaLib lib, String id) {
 			if (file == null) return null;
 
 			FolderItem parent = (FolderItem) file.getParent();
-			return create(id, parent, parent.getFile(), (VirtualFile) file.getFile(), lib);
+			return create(id, parent, (VirtualFile) file.getFile(), lib);
 		});
 	}
 
@@ -207,27 +216,30 @@ private void addTrack(String id, List<CueTrackItem> tracks, VirtualResource file
 		}
 	}
 
-	public CueTrackItem getTrack(int id) {
-		if (id > tracks.size()) return null;
+	FutureSupplier<Item> getTrack(int id) {
+		return data.get().map(d -> {
+			if (id > d.tracks.size()) return null;
 
-		CueTrackItem t = tracks.get(id - 1);
-		if (t.getTrackNumber() == id) return t;
+			CueTrackItem t = d.tracks.get(id - 1);
+			if (t.getTrackNumber() == id) return t;
 
-		for (CueTrackItem c : tracks) {
-			if (c.getTrackNumber() == id) return c;
-		}
+			for (CueTrackItem c : d.tracks) {
+				if (c.getTrackNumber() == id) return c;
+			}
 
-		return null;
+			return null;
+		});
 	}
 
 	@Override
 	public String getName() {
-		return name;
+		Data d = data.get().peek();
+		return (d == null) ? super.getName() : d.name;
 	}
 
 	@Override
 	protected FutureSupplier<String> buildSubtitle() {
-		return completed(subtitle);
+		return data.get().map(d -> d.subtitle);
 	}
 
 	@Override
@@ -238,6 +250,18 @@ public int getIcon() {
 	@SuppressWarnings({"unchecked", "rawtypes"})
 	@Override
 	public FutureSupplier<List<Item>> listChildren() {
-		return completed((List) tracks);
+		return data.get().map(d -> (List) d.tracks);
+	}
+
+	private static final class Data {
+		final String name;
+		final String subtitle;
+		final List<CueTrackItem> tracks;
+
+		Data(String name, String subtitle, List<CueTrackItem> tracks) {
+			this.name = name;
+			this.subtitle = subtitle;
+			this.tracks = tracks;
+		}
 	}
 }

fermata/src/main/java/me/aap/fermata/media/lib/CueTrackItem.java

@@ -66,9 +66,9 @@ static FutureSupplier<Item> create(DefaultMediaLib lib, String id) {
 		SharedTextBuilder tb = SharedTextBuilder.get();
 		tb.append(CueItem.SCHEME).append(id, i2, id.length());
 
-		return lib.getItem(tb.releaseString()).map(i -> {
+		return lib.getItem(tb.releaseString()).then(i -> {
 			CueItem cue = (CueItem) i;
-			if (cue == null) return null;
+			if (cue == null) return completedNull();
 
 			int n = Integer.parseInt(id.substring(i1 + 1, i2));
 			return cue.getTrack(n);

fermata/src/main/java/me/aap/fermata/media/lib/FolderItem.java

@@ -148,7 +148,7 @@ private List<Item> ls(List<VirtualResource> ls) {
 					}
 
 					cueBuf.append(name);
-					i = CueItem.create(cueBuf.toString(), this, getFile(), (VirtualFile) f, lib);
+					i = CueItem.create(cueBuf.toString(), this, (VirtualFile) f, lib);
 				} else if (M3uItem.isM3uFile(name)) {
 					if (m3uBuf == null) {
 						m3uBuf = new StringBuilder(id.length() + name.length() + 1);
@@ -159,7 +159,7 @@ private List<Item> ls(List<VirtualResource> ls) {
 					}
 
 					m3uBuf.append(name);
-					i = M3uItem.create(m3uBuf.toString(), this, getFile(), (VirtualFile) f, lib);
+					i = M3uItem.create(m3uBuf.toString(), this, (VirtualFile) f, lib);
 				} else {
 					if (fileBuf == null) {
 						fileBuf = new StringBuilder(id.length() + name.length() + 64);

fermata/src/main/java/me/aap/fermata/media/lib/ItemBase.java

@@ -9,6 +9,7 @@
 import androidx.annotation.Nullable;
 
 import java.util.Collection;
+import java.util.List;
 import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
 
 import me.aap.fermata.media.lib.MediaLib.BrowsableItem;
@@ -114,22 +115,20 @@ public FutureSupplier<MediaDescriptionCompat> getMediaDescription() {
 	protected FutureSupplier<String> buildTitle() {
 		BrowsableItem parent = requireNonNull(getParent());
 		BrowsableItemPrefs prefs = parent.getPrefs();
-		int seq = seqNum;
 
 		if (prefs.getTitleSeqNumPref()) {
-			if (seq == 0) {
-				Promise<String> load = new Promise<>();
+			FutureSupplier<List<Item>> getChildren = parent.getChildren();
 
+			if (getChildren.isDone()) {
+				return buildTitle(seqNum, prefs);
+			} else {
+				Promise<String> load = new Promise<>();
 				parent.getChildren().then(children -> {
-					int s = seqNum;
-					assertNotEquals(s, 0);
-					return buildTitle(s, prefs);
+					assertNotEquals(seqNum, 0);
+					return buildTitle(seqNum, prefs);
 				}).thenComplete(load);
-
 				buildTitle(0, prefs).onSuccess(t -> load.setProgress(t, 1, 2));
 				return load;
-			} else {
-				return buildTitle(seq, prefs);
 			}
 		} else {
 			return buildTitle(0, prefs);

fermata/src/main/java/me/aap/fermata/media/lib/M3uGroupItem.java

@@ -14,6 +14,7 @@
 
 import static java.util.Objects.requireNonNull;
 import static me.aap.utils.async.Completed.completed;
+import static me.aap.utils.async.Completed.completedNull;
 
 /**
  * @author Andrey Pavlenko
@@ -43,9 +44,9 @@ static FutureSupplier<Item> create(DefaultMediaLib lib, String id) {
 		SharedTextBuilder tb = SharedTextBuilder.get();
 		tb.append(M3uItem.SCHEME).append(id, end, id.length());
 
-		return lib.getItem(tb.releaseString()).map(i -> {
+		return lib.getItem(tb.releaseString()).then(i -> {
 			M3uItem m3u = (M3uItem) i;
-			return (m3u != null) ? m3u.getGroup(gid) : null;
+			return (m3u != null) ? m3u.getGroup(gid) : completedNull();
 		});
 	}