src/com/android/music/MusicUtils.java

/*
 * Copyright (C) 2008 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.music;

import android.app.Activity;
import android.content.ComponentName;
import android.content.ContentResolver;
import android.content.ContentUris;
import android.content.ContentValues;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.content.res.Resources;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.ColorFilter;
import android.graphics.PixelFormat;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.media.MediaFile;
import android.net.Uri;
import android.os.Environment;
import android.os.ParcelFileDescriptor;
import android.os.RemoteException;
import android.provider.MediaStore;
import android.provider.Settings;
import android.text.TextUtils;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.SubMenu;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.widget.TabWidget;
import android.widget.TextView;
import android.widget.Toast;

import java.io.File;
import java.io.FileDescriptor;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.util.Arrays;
import java.util.Formatter;
import java.util.HashMap;
import java.util.Locale;

public class MusicUtils {

    private static final String TAG = "MusicUtils";

    public interface Defs {
        public final static int OPEN_URL = 0;
        public final static int ADD_TO_PLAYLIST = 1;
        public final static int USE_AS_RINGTONE = 2;
        public final static int PLAYLIST_SELECTED = 3;
        public final static int NEW_PLAYLIST = 4;
        public final static int PLAY_SELECTION = 5;
        public final static int GOTO_START = 6;
        public final static int GOTO_PLAYBACK = 7;
        public final static int PARTY_SHUFFLE = 8;
        public final static int SHUFFLE_ALL = 9;
        public final static int DELETE_ITEM = 10;
        public final static int SCAN_DONE = 11;
        public final static int QUEUE = 12;
        public final static int CHILD_MENU_BASE = 13; // this should be the last item
    }

    public static String makeAlbumsLabel(Context context, int numalbums, int numsongs, boolean isUnknown) {
        // There are two formats for the albums/songs information:
        // "N Song(s)"  - used for unknown artist/album
        // "N Album(s)" - used for known albums
        
        StringBuilder songs_albums = new StringBuilder();

        Resources r = context.getResources();
        if (isUnknown) {
            if (numsongs == 1) {
                songs_albums.append(context.getString(R.string.onesong));
            } else {
                String f = r.getQuantityText(R.plurals.Nsongs, numsongs).toString();
                sFormatBuilder.setLength(0);
                sFormatter.format(f, Integer.valueOf(numsongs));
                songs_albums.append(sFormatBuilder);
            }
        } else {
            String f = r.getQuantityText(R.plurals.Nalbums, numalbums).toString();
            sFormatBuilder.setLength(0);
            sFormatter.format(f, Integer.valueOf(numalbums));
            songs_albums.append(sFormatBuilder);
            songs_albums.append(context.getString(R.string.albumsongseparator));
        }
        return songs_albums.toString();
    }

    /**
     * This is now only used for the query screen
     */
    public static String makeAlbumsSongsLabel(Context context, int numalbums, int numsongs, boolean isUnknown) {
        // There are several formats for the albums/songs information:
        // "1 Song"   - used if there is only 1 song
        // "N Songs" - used for the "unknown artist" item
        // "1 Album"/"N Songs" 
        // "N Album"/"M Songs"
        // Depending on locale, these may need to be further subdivided
        
        StringBuilder songs_albums = new StringBuilder();

        if (numsongs == 1) {
            songs_albums.append(context.getString(R.string.onesong));
        } else {
            Resources r = context.getResources();
            if (! isUnknown) {
                String f = r.getQuantityText(R.plurals.Nalbums, numalbums).toString();
                sFormatBuilder.setLength(0);
                sFormatter.format(f, Integer.valueOf(numalbums));
                songs_albums.append(sFormatBuilder);
                songs_albums.append(context.getString(R.string.albumsongseparator));
            }
            String f = r.getQuantityText(R.plurals.Nsongs, numsongs).toString();
            sFormatBuilder.setLength(0);
            sFormatter.format(f, Integer.valueOf(numsongs));
            songs_albums.append(sFormatBuilder);
        }
        return songs_albums.toString();
    }
    
    public static IMediaPlaybackService sService = null;
    private static HashMap<Context, ServiceBinder> sConnectionMap = new HashMap<Context, ServiceBinder>();

    public static boolean bindToService(Context context) {
        return bindToService(context, null);
    }

    public static boolean bindToService(Context context, ServiceConnection callback) {
        context.startService(new Intent(context, MediaPlaybackService.class));
        ServiceBinder sb = new ServiceBinder(callback);
        sConnectionMap.put(context, sb);
        return context.bindService((new Intent()).setClass(context,
                MediaPlaybackService.class), sb, 0);
    }
    
    public static void unbindFromService(Context context) {
        ServiceBinder sb = (ServiceBinder) sConnectionMap.remove(context);
        if (sb == null) {
            Log.e("MusicUtils", "Trying to unbind for unknown Context");
            return;
        }
        context.unbindService(sb);
        if (sConnectionMap.isEmpty()) {
            // presumably there is nobody interested in the service at this point,
            // so don't hang on to the ServiceConnection
            sService = null;
        }
    }

    private static class ServiceBinder implements ServiceConnection {
        ServiceConnection mCallback;
        ServiceBinder(ServiceConnection callback) {
            mCallback = callback;
        }
        
        public void onServiceConnected(ComponentName className, android.os.IBinder service) {
            sService = IMediaPlaybackService.Stub.asInterface(service);
            initAlbumArtCache();
            if (mCallback != null) {
                mCallback.onServiceConnected(className, service);
            }
        }
        
        public void onServiceDisconnected(ComponentName className) {
            if (mCallback != null) {
                mCallback.onServiceDisconnected(className);
            }
            sService = null;
        }
    }
    
    public static long getCurrentAlbumId() {
        if (sService != null) {
            try {
                return sService.getAlbumId();
            } catch (RemoteException ex) {
            }
        }
        return -1;
    }

    public static long getCurrentArtistId() {
        if (MusicUtils.sService != null) {
            try {
                return sService.getArtistId();
            } catch (RemoteException ex) {
            }
        }
        return -1;
    }

    public static long getCurrentAudioId() {
        if (MusicUtils.sService != null) {
            try {
                return sService.getAudioId();
            } catch (RemoteException ex) {
            }
        }
        return -1;
    }
    
    public static int getCurrentShuffleMode() {
        int mode = MediaPlaybackService.SHUFFLE_NONE;
        if (sService != null) {
            try {
                mode = sService.getShuffleMode();
            } catch (RemoteException ex) {
            }
        }
        return mode;
    }
    
    public static void togglePartyShuffle() {
        if (sService != null) {
            int shuffle = getCurrentShuffleMode();
            try {
                if (shuffle == MediaPlaybackService.SHUFFLE_AUTO) {
                    sService.setShuffleMode(MediaPlaybackService.SHUFFLE_NONE);
                } else {
                    sService.setShuffleMode(MediaPlaybackService.SHUFFLE_AUTO);
                }
            } catch (RemoteException ex) {
            }
        }
    }
    
    public static void setPartyShuffleMenuIcon(Menu menu) {
        MenuItem item = menu.findItem(Defs.PARTY_SHUFFLE);
        if (item != null) {
            int shuffle = MusicUtils.getCurrentShuffleMode();
            if (shuffle == MediaPlaybackService.SHUFFLE_AUTO) {
                item.setIcon(R.drawable.ic_menu_party_shuffle);
                item.setTitle(R.string.party_shuffle_off);
            } else {
                item.setIcon(R.drawable.ic_menu_party_shuffle);
                item.setTitle(R.string.party_shuffle);
            }
        }
    }
    
    /*
     * Returns true if a file is currently opened for playback (regardless
     * of whether it's playing or paused).
     */
    public static boolean isMusicLoaded() {
        if (MusicUtils.sService != null) {
            try {
                return sService.getPath() != null;
            } catch (RemoteException ex) {
            }
        }
        return false;
    }

    private final static long [] sEmptyList = new long[0];
    
    public static long [] getSongListForCursor(Cursor cursor) {
        if (cursor == null) {
            return sEmptyList;
        }
        int len = cursor.getCount();
        long [] list = new long[len];
        cursor.moveToFirst();
        int colidx = -1;
        try {
            colidx = cursor.getColumnIndexOrThrow(MediaStore.Audio.Playlists.Members.AUDIO_ID);
        } catch (IllegalArgumentException ex) {
            colidx = cursor.getColumnIndexOrThrow(MediaStore.Audio.Media._ID);
        }
        for (int i = 0; i < len; i++) {
            list[i] = cursor.getLong(colidx);
            cursor.moveToNext();
        }
        return list;
    }

    public static long [] getSongListForArtist(Context context, long id) {
        final String[] ccols = new String[] { MediaStore.Audio.Media._ID };
        String where = MediaStore.Audio.Media.ARTIST_ID + "=" + id + " AND " + 
        MediaStore.Audio.Media.IS_MUSIC + "=1";
        Cursor cursor = query(context, MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,
                ccols, where, null,
                MediaStore.Audio.Media.ALBUM_KEY + ","  + MediaStore.Audio.Media.TRACK);
        
        if (cursor != null) {
            long [] list = getSongListForCursor(cursor);
            cursor.close();
            return list;
        }
        return sEmptyList;
    }

    public static long [] getSongListForAlbum(Context context, long id) {
        final String[] ccols = new String[] { MediaStore.Audio.Media._ID };
        String where = MediaStore.Audio.Media.ALBUM_ID + "=" + id + " AND " + 
                MediaStore.Audio.Media.IS_MUSIC + "=1";
        Cursor cursor = query(context, MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,
                ccols, where, null, MediaStore.Audio.Media.TRACK);

        if (cursor != null) {
            long [] list = getSongListForCursor(cursor);
            cursor.close();
            return list;
        }
        return sEmptyList;
    }

    public static long [] getSongListForPlaylist(Context context, long plid) {
        final String[] ccols = new String[] { MediaStore.Audio.Playlists.Members.AUDIO_ID };
        Cursor cursor = query(context, MediaStore.Audio.Playlists.Members.getContentUri("external", plid),
                ccols, null, null, MediaStore.Audio.Playlists.Members.DEFAULT_SORT_ORDER);
        
        if (cursor != null) {
            long [] list = getSongListForCursor(cursor);
            cursor.close();
            return list;
        }
        return sEmptyList;
    }
    
    public static void playPlaylist(Context context, long plid) {
        long [] list = getSongListForPlaylist(context, plid);
        if (list != null) {
            playAll(context, list, -1, false);
        }
    }

    public static long [] getAllSongs(Context context) {
        Cursor c = query(context, MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,
                new String[] {MediaStore.Audio.Media._ID}, MediaStore.Audio.Media.IS_MUSIC + "=1",
                null, null);
        try {
            if (c == null || c.getCount() == 0) {
                return null;
            }
            int len = c.getCount();
            long [] list = new long[len];
            for (int i = 0; i < len; i++) {
                c.moveToNext();
                list[i] = c.getLong(0);
            }

            return list;
        } finally {
            if (c != null) {
                c.close();
            }
        }
    }

    /**
     * Fills out the given submenu with items for "new playlist" and
     * any existing playlists. When the user selects an item, the
     * application will receive PLAYLIST_SELECTED with the Uri of
     * the selected playlist, NEW_PLAYLIST if a new playlist
     * should be created, and QUEUE if the "current playlist" was
     * selected.
     * @param context The context to use for creating the menu items
     * @param sub The submenu to add the items to.
     */
    public static void makePlaylistMenu(Context context, SubMenu sub) {
        String[] cols = new String[] {
                MediaStore.Audio.Playlists._ID,
                MediaStore.Audio.Playlists.NAME
        };
        ContentResolver resolver = context.getContentResolver();
        if (resolver == null) {
            System.out.println("resolver = null");
        } else {
            String whereclause = MediaStore.Audio.Playlists.NAME + " != ''";
            Cursor cur = resolver.query(MediaStore.Audio.Playlists.EXTERNAL_CONTENT_URI,
                cols, whereclause, null,
                MediaStore.Audio.Playlists.NAME);
            sub.clear();
            sub.add(1, Defs.QUEUE, 0, R.string.queue);
            sub.add(1, Defs.NEW_PLAYLIST, 0, R.string.new_playlist);
            if (cur != null && cur.getCount() > 0) {
                //sub.addSeparator(1, 0);
                cur.moveToFirst();
                while (! cur.isAfterLast()) {
                    Intent intent = new Intent();
                    intent.putExtra("playlist", cur.getLong(0));
//                    if (cur.getInt(0) == mLastPlaylistSelected) {
//                        sub.add(0, MusicBaseActivity.PLAYLIST_SELECTED, cur.getString(1)).setIntent(intent);
//                    } else {
                        sub.add(1, Defs.PLAYLIST_SELECTED, 0, cur.getString(1)).setIntent(intent);
//                    }
                    cur.moveToNext();
                }
            }
            if (cur != null) {
                cur.close();
            }
        }
    }

    public static void clearPlaylist(Context context, int plid) {
        
        Uri uri = MediaStore.Audio.Playlists.Members.getContentUri("external", plid);
        context.getContentResolver().delete(uri, null, null);
        return;
    }
    
    public static void deleteTracks(Context context, long [] list) {
        
        String [] cols = new String [] { MediaStore.Audio.Media._ID, 
                MediaStore.Audio.Media.DATA, MediaStore.Audio.Media.ALBUM_ID };
        StringBuilder where = new StringBuilder();
        where.append(MediaStore.Audio.Media._ID + " IN (");
        for (int i = 0; i < list.length; i++) {
            where.append(list[i]);
            if (i < list.length - 1) {
                where.append(",");
            }
        }
        where.append(")");
        Cursor c = query(context, MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, cols,
                where.toString(), null, null);

        if (c != null) {

            // step 1: remove selected tracks from the current playlist, as well
            // as from the album art cache
            try {
                c.moveToFirst();
                while (! c.isAfterLast()) {
                    // remove from current playlist
                    long id = c.getLong(0);
                    sService.removeTrack(id);
                    // remove from album art cache
                    long artIndex = c.getLong(2);
                    synchronized(sArtCache) {
                        sArtCache.remove(artIndex);
                    }
                    c.moveToNext();
                }
            } catch (RemoteException ex) {
            }

            // step 2: remove selected tracks from the database
            context.getContentResolver().delete(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, where.toString(), null);

            // step 3: remove files from card
            c.moveToFirst();
            while (! c.isAfterLast()) {
                String name = c.getString(1);
                File f = new File(name);
                try {  // File.delete can throw a security exception
                    if (!f.delete()) {
                        // I'm not sure if we'd ever get here (deletion would
                        // have to fail, but no exception thrown)
                        Log.e("MusicUtils", "Failed to delete file " + name);
                    }
                    c.moveToNext();
                } catch (SecurityException ex) {
                    c.moveToNext();
                }
            }
            c.close();
        }

        String message = context.getResources().getQuantityString(
                R.plurals.NNNtracksdeleted, list.length, Integer.valueOf(list.length));
        
        Toast.makeText(context, message, Toast.LENGTH_SHORT).show();
        // We deleted a number of tracks, which could affect any number of things
        // in the media content domain, so update everything.
        context.getContentResolver().notifyChange(Uri.parse("content://media"), null);
    }
    
    public static void addToCurrentPlaylist(Context context, long [] list) {
        if (sService == null) {
            return;
        }
        try {
            sService.enqueue(list, MediaPlaybackService.LAST);
            String message = context.getResources().getQuantityString(
                    R.plurals.NNNtrackstoplaylist, list.length, Integer.valueOf(list.length));
            Toast.makeText(context, message, Toast.LENGTH_SHORT).show();
        } catch (RemoteException ex) {
        }
    }
    
    public static void addToPlaylist(Context context, long [] ids, long playlistid) {
        if (ids == null) {
            // this shouldn't happen (the menuitems shouldn't be visible
            // unless the selected item represents something playable
            Log.e("MusicBase", "ListSelection null");
        } else {
            int size = ids.length;
            ContentValues values [] = new ContentValues[size];
            ContentResolver resolver = context.getContentResolver();
            // need to determine the number of items currently in the playlist,
            // so the play_order field can be maintained.
            String[] cols = new String[] {
                    "count(*)"
            };
            Uri uri = MediaStore.Audio.Playlists.Members.getContentUri("external", playlistid);
            Cursor cur = resolver.query(uri, cols, null, null, null);
            cur.moveToFirst();
            int base = cur.getInt(0);
            cur.close();

            for (int i = 0; i < size; i++) {
                values[i] = new ContentValues();
                values[i].put(MediaStore.Audio.Playlists.Members.PLAY_ORDER, Integer.valueOf(base + i));
                values[i].put(MediaStore.Audio.Playlists.Members.AUDIO_ID, ids[i]);
            }
            resolver.bulkInsert(uri, values);
            String message = context.getResources().getQuantityString(
                    R.plurals.NNNtrackstoplaylist, size, Integer.valueOf(size));
            Toast.makeText(context, message, Toast.LENGTH_SHORT).show();
            //mLastPlaylistSelected = playlistid;
        }
    }

    public static Cursor query(Context context, Uri uri, String[] projection,
            String selection, String[] selectionArgs, String sortOrder, int limit) {
        try {
            ContentResolver resolver = context.getContentResolver();
            if (resolver == null) {
                return null;
            }
            if (limit > 0) {
                uri = uri.buildUpon().appendQueryParameter("limit", "" + limit).build();
            }
            return resolver.query(uri, projection, selection, selectionArgs, sortOrder);
         } catch (UnsupportedOperationException ex) {
            return null;
        }
        
    }
    public static Cursor query(Context context, Uri uri, String[] projection,
            String selection, String[] selectionArgs, String sortOrder) {
        return query(context, uri, projection, selection, selectionArgs, sortOrder, 0);
    }
    
    public static boolean isMediaScannerScanning(Context context) {
        boolean result = false;
        Cursor cursor = query(context, MediaStore.getMediaScannerUri(), 
                new String [] { MediaStore.MEDIA_SCANNER_VOLUME }, null, null, null);
        if (cursor != null) {
            if (cursor.getCount() == 1) {
                cursor.moveToFirst();
                result = "external".equals(cursor.getString(0));
            }
            cursor.close(); 
        } 

        return result;
    }
    
    public static void setSpinnerState(Activity a) {
        if (isMediaScannerScanning(a)) {
            // start the progress spinner
            a.getWindow().setFeatureInt(
                    Window.FEATURE_INDETERMINATE_PROGRESS,
                    Window.PROGRESS_INDETERMINATE_ON);

            a.getWindow().setFeatureInt(
                    Window.FEATURE_INDETERMINATE_PROGRESS,
                    Window.PROGRESS_VISIBILITY_ON);
        } else {
            // stop the progress spinner
            a.getWindow().setFeatureInt(
                    Window.FEATURE_INDETERMINATE_PROGRESS,
                    Window.PROGRESS_VISIBILITY_OFF);
        }
    }
    
    private static String mLastSdStatus;

    public static void displayDatabaseError(Activity a) {
        String status = Environment.getExternalStorageState();
        int title = R.string.sdcard_error_title;
        int message = R.string.sdcard_error_message;
        
        if (status.equals(Environment.MEDIA_SHARED) ||
                status.equals(Environment.MEDIA_UNMOUNTED)) {
            title = R.string.sdcard_busy_title;
            message = R.string.sdcard_busy_message;
        } else if (status.equals(Environment.MEDIA_REMOVED)) {
            title = R.string.sdcard_missing_title;
            message = R.string.sdcard_missing_message;
        } else if (status.equals(Environment.MEDIA_MOUNTED)){
            // The card is mounted, but we didn't get a valid cursor.
            // This probably means the mediascanner hasn't started scanning the
            // card yet (there is a small window of time during boot where this
            // will happen).
            a.setTitle("");
            Intent intent = new Intent();
            intent.setClass(a, ScanningProgress.class);
            a.startActivityForResult(intent, Defs.SCAN_DONE);
        } else if (!TextUtils.equals(mLastSdStatus, status)) {
            mLastSdStatus = status;
            Log.d(TAG, "sd card: " + status);
        }

        a.setTitle(title);
        View v = a.findViewById(R.id.sd_message);
        if (v != null) {
            v.setVisibility(View.VISIBLE);
        }
        v = a.findViewById(R.id.sd_icon);
        if (v != null) {
            v.setVisibility(View.VISIBLE);
        }
        v = a.findViewById(android.R.id.list);
        if (v != null) {
            v.setVisibility(View.GONE);
        }
        v = a.findViewById(R.id.buttonbar);
        if (v != null) {
            v.setVisibility(View.GONE);
        }
        TextView tv = (TextView) a.findViewById(R.id.sd_message);
        tv.setText(message);
    }
    
    public static void hideDatabaseError(Activity a) {
        View v = a.findViewById(R.id.sd_message);
        if (v != null) {
            v.setVisibility(View.GONE);
        }
        v = a.findViewById(R.id.sd_icon);
        if (v != null) {
            v.setVisibility(View.GONE);
        }
        v = a.findViewById(android.R.id.list);
        if (v != null) {
            v.setVisibility(View.VISIBLE);
        }
    }

    static protected Uri getContentURIForPath(String path) {
        return Uri.fromFile(new File(path));
    }

    
    /*  Try to use String.format() as little as possible, because it creates a
     *  new Formatter every time you call it, which is very inefficient.
     *  Reusing an existing Formatter more than tripled the speed of
     *  makeTimeString().
     *  This Formatter/StringBuilder are also used by makeAlbumSongsLabel()
     */
    private static StringBuilder sFormatBuilder = new StringBuilder();
    private static Formatter sFormatter = new Formatter(sFormatBuilder, Locale.getDefault());
    private static final Object[] sTimeArgs = new Object[5];

    public static String makeTimeString(Context context, long secs) {
        String durationformat = context.getString(
                secs < 3600 ? R.string.durationformatshort : R.string.durationformatlong);
        
        /* Provide multiple arguments so the format can be changed easily
         * by modifying the xml.
         */
        sFormatBuilder.setLength(0);

        final Object[] timeArgs = sTimeArgs;
        timeArgs[0] = secs / 3600;
        timeArgs[1] = secs / 60;
        timeArgs[2] = (secs / 60) % 60;
        timeArgs[3] = secs;
        timeArgs[4] = secs % 60;

        return sFormatter.format(durationformat, timeArgs).toString();
    }
    
    public static void shuffleAll(Context context, Cursor cursor) {
        playAll(context, cursor, 0, true);
    }

    public static void playAll(Context context, Cursor cursor) {
        playAll(context, cursor, 0, false);
    }
    
    public static void playAll(Context context, Cursor cursor, int position) {
        playAll(context, cursor, position, false);
    }
    
    public static void playAll(Context context, long [] list, int position) {
        playAll(context, list, position, false);
    }
    
    private static void playAll(Context context, Cursor cursor, int position, boolean force_shuffle) {
    
        long [] list = getSongListForCursor(cursor);
        playAll(context, list, position, force_shuffle);
    }
    
    private static void playAll(Context context, long [] list, int position, boolean force_shuffle) {
        if (list.length == 0 || sService == null) {
            Log.d("MusicUtils", "attempt to play empty song list");
            // Don't try to play empty playlists. Nothing good will come of it.
            String message = context.getString(R.string.emptyplaylist, list.length);
            Toast.makeText(context, message, Toast.LENGTH_SHORT).show();
            return;
        }
        try {
            if (force_shuffle) {
                sService.setShuffleMode(MediaPlaybackService.SHUFFLE_NORMAL);
            }
            long curid = sService.getAudioId();
            int curpos = sService.getQueuePosition();
            if (position != -1 && curpos == position && curid == list[position]) {
                // The selected file is the file that's currently playing;
                // figure out if we need to restart with a new playlist,
                // or just launch the playback activity.
                long [] playlist = sService.getQueue();
                if (Arrays.equals(list, playlist)) {
                    // we don't need to set a new list, but we should resume playback if needed
                    sService.play();
                    return; // the 'finally' block will still run
                }
            }
            if (position < 0) {
                position = 0;
            }
            sService.open(list, force_shuffle ? -1 : position);
            sService.play();
        } catch (RemoteException ex) {
        } finally {
            Intent intent = new Intent(context, MediaPlaybackActivity.class)
                .setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
            context.startActivity(intent);
        }
    }
    
    public static void clearQueue() {
        try {
            sService.removeTracks(0, Integer.MAX_VALUE);
        } catch (RemoteException ex) {
        }
    }
    
    // A really simple BitmapDrawable-like class, that doesn't do
    // scaling, dithering or filtering.
    private static class FastBitmapDrawable extends Drawable {
        private Bitmap mBitmap;
        public FastBitmapDrawable(Bitmap b) {
            mBitmap = b;
        }
        @Override
        public void draw(Canvas canvas) {
            canvas.drawBitmap(mBitmap, 0, 0, null);
        }
        @Override
        public int getOpacity() {
            return PixelFormat.OPAQUE;
        }
        @Override
        public void setAlpha(int alpha) {
        }
        @Override
        public void setColorFilter(ColorFilter cf) {
        }
    }
    
    private static int sArtId = -2;
    private static Bitmap mCachedBit = null;
    private static final BitmapFactory.Options sBitmapOptionsCache = new BitmapFactory.Options();
    private static final BitmapFactory.Options sBitmapOptions = new BitmapFactory.Options();
    private static final Uri sArtworkUri = Uri.parse("content://media/external/audio/albumart");
    private static final HashMap<Long, Drawable> sArtCache = new HashMap<Long, Drawable>();
    private static int sArtCacheId = -1;
    
    static {
        // for the cache, 
        // 565 is faster to decode and display
        // and we don't want to dither here because the image will be scaled down later
        sBitmapOptionsCache.inPreferredConfig = Bitmap.Config.RGB_565;
        sBitmapOptionsCache.inDither = false;

        sBitmapOptions.inPreferredConfig = Bitmap.Config.RGB_565;
        sBitmapOptions.inDither = false;
    }

    public static void initAlbumArtCache() {
        try {
            int id = sService.getMediaMountedCount();
            if (id != sArtCacheId) {
                clearAlbumArtCache();
                sArtCacheId = id; 
            }
        } catch (RemoteException e) {
            e.printStackTrace();
        }
    }

    public static void clearAlbumArtCache() {
        synchronized(sArtCache) {
            sArtCache.clear();
        }
    }
    
    public static Drawable getCachedArtwork(Context context, long artIndex, BitmapDrawable defaultArtwork) {
        Drawable d = null;
        synchronized(sArtCache) {
            d = sArtCache.get(artIndex);
        }
        if (d == null) {
            d = defaultArtwork;
            final Bitmap icon = defaultArtwork.getBitmap();
            int w = icon.getWidth();
            int h = icon.getHeight();
            Bitmap b = MusicUtils.getArtworkQuick(context, artIndex, w, h);
            if (b != null) {
                d = new FastBitmapDrawable(b);
                synchronized(sArtCache) {
                    // the cache may have changed since we checked
                    Drawable value = sArtCache.get(artIndex);
                    if (value == null) {
                        sArtCache.put(artIndex, d);
                    } else {
                        d = value;
                    }
                }
            }
        }
        return d;
    }

    // Get album art for specified album. This method will not try to
    // fall back to getting artwork directly from the file, nor will
    // it attempt to repair the database.
    private static Bitmap getArtworkQuick(Context context, long album_id, int w, int h) {
        // NOTE: There is in fact a 1 pixel border on the right side in the ImageView
        // used to display this drawable. Take it into account now, so we don't have to
        // scale later.
        w -= 1;
        ContentResolver res = context.getContentResolver();
        Uri uri = ContentUris.withAppendedId(sArtworkUri, album_id);
        if (uri != null) {
            ParcelFileDescriptor fd = null;
            try {
                fd = res.openFileDescriptor(uri, "r");
                int sampleSize = 1;
                
                // Compute the closest power-of-two scale factor 
                // and pass that to sBitmapOptionsCache.inSampleSize, which will
                // result in faster decoding and better quality
                sBitmapOptionsCache.inJustDecodeBounds = true;
                BitmapFactory.decodeFileDescriptor(
                        fd.getFileDescriptor(), null, sBitmapOptionsCache);
                int nextWidth = sBitmapOptionsCache.outWidth >> 1;
                int nextHeight = sBitmapOptionsCache.outHeight >> 1;
                while (nextWidth>w && nextHeight>h) {
                    sampleSize <<= 1;
                    nextWidth >>= 1;
                    nextHeight >>= 1;
                }

                sBitmapOptionsCache.inSampleSize = sampleSize;
                sBitmapOptionsCache.inJustDecodeBounds = false;
                Bitmap b = BitmapFactory.decodeFileDescriptor(
                        fd.getFileDescriptor(), null, sBitmapOptionsCache);

                if (b != null) {
                    // finally rescale to exactly the size we need
                    if (sBitmapOptionsCache.outWidth != w || sBitmapOptionsCache.outHeight != h) {
                        Bitmap tmp = Bitmap.createScaledBitmap(b, w, h, true);
                        // Bitmap.createScaledBitmap() can return the same bitmap
                        if (tmp != b) b.recycle();
                        b = tmp;
                    }
                }
                
                return b;
            } catch (FileNotFoundException e) {
            } finally {
                try {
                    if (fd != null)
                        fd.close();
                } catch (IOException e) {
                }
            }
        }
        return null;
    }
    
    /** Get album art for specified album. You should not pass in the album id
     * for the "unknown" album here (use -1 instead)
     */
    public static Bitmap getArtwork(Context context, long song_id, long album_id) {

        if (album_id < 0) {
            // This is something that is not in the database, so get the album art directly
            // from the file.
            if (song_id >= 0) {
                Bitmap bm = getArtworkFromFile(context, song_id, -1);
                if (bm != null) {
                    return bm;
                }
            }
            return getDefaultArtwork(context);
        }

        ContentResolver res = context.getContentResolver();
        Uri uri = ContentUris.withAppendedId(sArtworkUri, album_id);
        if (uri != null) {
            InputStream in = null;
            try {
                in = res.openInputStream(uri);
                return BitmapFactory.decodeStream(in, null, sBitmapOptions);
            } catch (FileNotFoundException ex) {
                // The album art thumbnail does not actually exist. Maybe the user deleted it, or
                // maybe it never existed to begin with.
                Bitmap bm = getArtworkFromFile(context, song_id, album_id);
                if (bm != null) {
                    if (bm.getConfig() == null) {
                        bm = bm.copy(Bitmap.Config.RGB_565, false);
                        if (bm == null) {
                            return getDefaultArtwork(context);
                        }
                    }
                } else {
                    bm = getDefaultArtwork(context);
                }
                return bm;
            } finally {
                try {
                    if (in != null) {
                        in.close();
                    }
                } catch (IOException ex) {
                }
            }
        }
        
        return null;
    }
    
    // get album art for specified file
    private static final String sExternalMediaUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI.toString();
    private static Bitmap getArtworkFromFile(Context context, long songid, long albumid) {
        Bitmap bm = null;
        byte [] art = null;
        String path = null;

        if (albumid < 0 && songid < 0) {
            throw new IllegalArgumentException("Must specify an album or a song id");
        }

        try {
            if (albumid < 0) {
                Uri uri = Uri.parse("content://media/external/audio/media/" + songid + "/albumart");
                ParcelFileDescriptor pfd = context.getContentResolver().openFileDescriptor(uri, "r");
                if (pfd != null) {
                    FileDescriptor fd = pfd.getFileDescriptor();
                    bm = BitmapFactory.decodeFileDescriptor(fd);
                }
            } else {
                Uri uri = ContentUris.withAppendedId(sArtworkUri, albumid);
                ParcelFileDescriptor pfd = context.getContentResolver().openFileDescriptor(uri, "r");
                if (pfd != null) {
                    FileDescriptor fd = pfd.getFileDescriptor();
                    bm = BitmapFactory.decodeFileDescriptor(fd);
                }
            }
        } catch (FileNotFoundException ex) {
            //
        }
        if (bm != null) {
            mCachedBit = bm;
        }
        return bm;
    }
    
    private static Bitmap getDefaultArtwork(Context context) {
        BitmapFactory.Options opts = new BitmapFactory.Options();
        opts.inPreferredConfig = Bitmap.Config.ARGB_8888;
        return BitmapFactory.decodeStream(
                context.getResources().openRawResource(R.drawable.albumart_mp_unknown), null, opts);
    }
    
    static int getIntPref(Context context, String name, int def) {
        SharedPreferences prefs =
            context.getSharedPreferences("com.android.music", Context.MODE_PRIVATE);
        return prefs.getInt(name, def);
    }
    
    static void setIntPref(Context context, String name, int value) {
        SharedPreferences prefs =
            context.getSharedPreferences("com.android.music", Context.MODE_PRIVATE);
        Editor ed = prefs.edit();
        ed.putInt(name, value);
        ed.commit();
    }

    static void setRingtone(Context context, long id) {
        ContentResolver resolver = context.getContentResolver();
        // Set the flag in the database to mark this as a ringtone
        Uri ringUri = ContentUris.withAppendedId(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, id);
        try {
            ContentValues values = new ContentValues(2);
            values.put(MediaStore.Audio.Media.IS_RINGTONE, "1");
            values.put(MediaStore.Audio.Media.IS_ALARM, "1");
            resolver.update(ringUri, values, null, null);
        } catch (UnsupportedOperationException ex) {
            // most likely the card just got unmounted
            Log.e(TAG, "couldn't set ringtone flag for id " + id);
            return;
        }

        String[] cols = new String[] {
                MediaStore.Audio.Media._ID,
                MediaStore.Audio.Media.DATA,
                MediaStore.Audio.Media.TITLE
        };

        String where = MediaStore.Audio.Media._ID + "=" + id;
        Cursor cursor = query(context, MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,
                cols, where , null, null);
        try {
            if (cursor != null && cursor.getCount() == 1) {
                // Set the system setting to make this the current ringtone
                cursor.moveToFirst();
                Settings.System.putString(resolver, Settings.System.RINGTONE, ringUri.toString());
                String message = context.getString(R.string.ringtone_set, cursor.getString(2));
                Toast.makeText(context, message, Toast.LENGTH_SHORT).show();
            }
        } finally {
            if (cursor != null) {
                cursor.close();
            }
        }
    }
    
    static int sActiveTabIndex = -1;
    
    static boolean updateButtonBar(Activity a, int highlight) {
        final TabWidget ll = (TabWidget) a.findViewById(R.id.buttonbar);
        boolean withtabs = false;
        Intent intent = a.getIntent();
        if (intent != null) {
            withtabs = intent.getBooleanExtra("withtabs", false);
        }
        
        if (highlight == 0 || !withtabs) {
            ll.setVisibility(View.GONE);
            return withtabs;
        } else if (withtabs) {
            ll.setVisibility(View.VISIBLE);
        }
        for (int i = ll.getChildCount() - 1; i >= 0; i--) {
            
            View v = ll.getChildAt(i);
            boolean isActive = (v.getId() == highlight);
            if (isActive) {
                ll.setCurrentTab(i);
                sActiveTabIndex = i;
            }
            v.setTag(i);
            v.setOnFocusChangeListener(new View.OnFocusChangeListener() {

                public void onFocusChange(View v, boolean hasFocus) {
                    if (hasFocus) {
                        for (int i = 0; i < ll.getTabCount(); i++) {
                            if (ll.getChildTabViewAt(i) == v) {
                                ll.setCurrentTab(i);
                                processTabClick((Activity)ll.getContext(), v, ll.getChildAt(sActiveTabIndex).getId());
                                break;
                            }
                        }
                    }
                }});
            
            v.setOnClickListener(new View.OnClickListener() {

                public void onClick(View v) {
                    processTabClick((Activity)ll.getContext(), v, ll.getChildAt(sActiveTabIndex).getId());
                }});
        }
        return withtabs;
    }

    static void processTabClick(Activity a, View v, int current) {
        int id = v.getId();
        if (id == current) {
            return;
        }

        final TabWidget ll = (TabWidget) a.findViewById(R.id.buttonbar);
        ll.setCurrentTab((Integer) v.getTag());

        activateTab(a, id);
        if (id != R.id.nowplayingtab) {
            setIntPref(a, "activetab", id);
        }
    }
    
    static void activateTab(Activity a, int id) {
        Intent intent = new Intent(Intent.ACTION_PICK);
        switch (id) {
            case R.id.artisttab:
                intent.setDataAndType(Uri.EMPTY, "vnd.android.cursor.dir/artistalbum");
                break;
            case R.id.albumtab:
                intent.setDataAndType(Uri.EMPTY, "vnd.android.cursor.dir/album");
                break;
            case R.id.songtab:
                intent.setDataAndType(Uri.EMPTY, "vnd.android.cursor.dir/track");
                break;
            case R.id.playlisttab:
                intent.setDataAndType(Uri.EMPTY, MediaStore.Audio.Playlists.CONTENT_TYPE);
                break;
            case R.id.nowplayingtab:
                intent = new Intent(a, MediaPlaybackActivity.class);
                a.startActivity(intent);
                // fall through and return
            default:
                return;
        }
        intent.putExtra("withtabs", true);
        intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
        a.startActivity(intent);
        a.finish();
        a.overridePendingTransition(0, 0);
    }
    
    static void updateNowPlaying(Activity a) {
        View nowPlayingView = a.findViewById(R.id.nowplaying);
        if (nowPlayingView == null) {
            return;
        }
        try {
            boolean withtabs = false;
            Intent intent = a.getIntent();
            if (intent != null) {
                withtabs = intent.getBooleanExtra("withtabs", false);
            }
            if (true && MusicUtils.sService != null && MusicUtils.sService.getAudioId() != -1) {
                TextView title = (TextView) nowPlayingView.findViewById(R.id.title);
                TextView artist = (TextView) nowPlayingView.findViewById(R.id.artist);
                title.setText(MusicUtils.sService.getTrackName());
                String artistName = MusicUtils.sService.getArtistName();
                if (MediaFile.UNKNOWN_STRING.equals(artistName)) {
                    artistName = a.getString(R.string.unknown_artist_name);
                }
                artist.setText(artistName);
                //mNowPlayingView.setOnFocusChangeListener(mFocuser);
                //mNowPlayingView.setOnClickListener(this);
                nowPlayingView.setVisibility(View.VISIBLE);
                nowPlayingView.setOnClickListener(new View.OnClickListener() {

                    public void onClick(View v) {
                        Context c = v.getContext();
                        c.startActivity(new Intent(c, MediaPlaybackActivity.class));
                    }});
                return;
            }
        } catch (RemoteException ex) {
        }
        nowPlayingView.setVisibility(View.GONE);
    }

}