/**
* Builds a query that will return all the songs represented by the given parameters.
*
* @param type MediaUtils.TYPE_ARTIST, TYPE_ALBUM, or TYPE_SONG.
* @param id The MediaStore id of the song, artist, or album.
* @param projection The columns to query.
* @param select An extra selection to pass to the query, or null.
* @return The initialized query.
*/
private static QueryTask buildMediaQuery(int type, long id, String[] projection, String select) {
Uri media = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
StringBuilder selection = new StringBuilder();
String sort = DEFAULT_SORT;
switch (type) {
case TYPE_SONG:
selection.append(MediaStore.Audio.Media._ID);
break;
case TYPE_ARTIST:
selection.append(MediaStore.Audio.Media.ARTIST_ID);
break;
case TYPE_ALBUM:
selection.append(MediaStore.Audio.Media.ALBUM_ID);
sort = ALBUM_SORT;
break;
default:
throw new IllegalArgumentException("Invalid type specified: " + type);
}
selection.append('=');
selection.append(id);
selection.append(" AND length(_data) AND " + MediaStore.Audio.Media.IS_MUSIC);
if (select != null) {
selection.append(" AND ");
selection.append(select);
}
QueryTask result = new QueryTask(media, projection, selection.toString(), null, sort);
result.type = type;
return result;
}
/**
* Builds a query that will return all the songs in the playlist with the given id.
*
* @param id The id of the playlist in MediaStore.Audio.Playlists.
* @param projection The columns to query.
* @param selection The selection to pass to the query, or null.
* @return The initialized query.
*/
public static QueryTask buildPlaylistQuery(long id, String[] projection, String selection) {
Uri uri = MediaStore.Audio.Playlists.Members.getContentUri("external", id);
String sort = MediaStore.Audio.Playlists.Members.PLAY_ORDER;
QueryTask result = new QueryTask(uri, projection, selection, null, sort);
result.type = TYPE_PLAYLIST;
return result;
}
/**
* Build a query that will contain all the media under the given path.
*
* @param path The path, e.g. /mnt/sdcard/music/
* @param projection The columns to query
* @return The initialized query.
*/
public static QueryTask buildFileQuery(String path, String[] projection) {
/* make sure that the path is:
-> fixed-up to point to the real mountpoint if user browsed to the mediadir symlink
-> terminated with a / if it is a directory
-> ended with a % for the LIKE query
*/
path = addDirEndSlash(sanitizeMediaPath(path)) + "%";
final String query = "_data LIKE ? AND " + MediaStore.Audio.Media.IS_MUSIC;
String[] qargs = {path};
Uri media = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
QueryTask result = new QueryTask(media, projection, query, qargs, DEFAULT_SORT);
result.type = TYPE_FILE;
return result;
}
/**
* Builds a query that will return all the songs in the genre with the given id.
*
* @param id The id of the genre in MediaStore.Audio.Genres.
* @param projection The columns to query.
* @param selection The selection to pass to the query, or null.
* @param selectionArgs The arguments to substitute into the selection.
* @param sort The sort order.
* @param type The media type to query and return
* @param returnSongs returns matching songs instead of `type' if true
*/
public static QueryTask buildGenreQuery(
long id,
String[] projection,
String selection,
String[] selectionArgs,
String sort,
int type,
boolean returnSongs) {
// Note: This function works on a raw sql query with way too much internal
// knowledge about the mediaProvider SQL table layout. Yes: it's ugly.
// The reason for this mess is that android has a very crippled genre implementation
// and does, for example, not allow us to query the albumbs beloging to a genre.
Uri uri = MediaStore.Audio.Genres.Members.getContentUri("external", id);
String[] clonedProjection =
projection
.clone(); // we modify the projection, but this should not be visible to the caller
String sql = "";
String authority = "audio";
if (type == TYPE_ARTIST) authority = "artist_info";
if (type == TYPE_ALBUM) authority = "album_info";
// Our raw SQL query includes the album_info table (well: it's actually a view)
// which shares some columns with audio.
// This regexp should matche duplicate column names and forces them to use
// the audio table as a source
final String _FORCE_AUDIO_SRC = "(^|[ |,\\(])(_id|album(_\\w+)?|artist(_\\w+)?)";
// Prefix the SELECTed rows with the current table authority name
for (int i = 0; i < clonedProjection.length; i++) {
if (clonedProjection[i].equals("0") == false) // do not prefix fake rows
clonedProjection[i] = (returnSongs ? "audio" : authority) + "." + clonedProjection[i];
}
sql += TextUtils.join(", ", clonedProjection);
sql +=
" FROM audio_genres_map_noid, audio" + (authority.equals("audio") ? "" : ", " + authority);
sql += " WHERE(audio._id = audio_id AND genre_id=?)";
if (selection != null && selection.length() > 0)
sql += " AND(" + selection.replaceAll(_FORCE_AUDIO_SRC, "$1audio.$2") + ")";
if (type == TYPE_ARTIST)
sql +=
" AND(artist_info._id = audio.artist_id)"
+ (returnSongs ? "" : " GROUP BY artist_info._id");
if (type == TYPE_ALBUM)
sql +=
" AND(album_info._id = audio.album_id)" + (returnSongs ? "" : " GROUP BY album_info._id");
if (sort != null && sort.length() > 0)
sql += " ORDER BY " + sort.replaceAll(_FORCE_AUDIO_SRC, "$1audio.$2");
// We are now turning this into an sql injection. Fun times.
clonedProjection[0] = sql + " --";
QueryTask result = new QueryTask(uri, clonedProjection, selection, selectionArgs, sort);
result.type = TYPE_GENRE;
return result;
}
