/*
* Copyright (C) 2015 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.example.android.supportv4.media.utils;
import android.support.v4.media.MediaMetadataCompat;
import android.support.v4.media.session.MediaSessionCompat;
import android.util.Log;
import com.example.android.supportv4.media.model.MusicProvider;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import static com.example.android.supportv4.media.utils.MediaIDHelper.MEDIA_ID_MUSICS_BY_GENRE;
import static com.example.android.supportv4.media.utils.MediaIDHelper.MEDIA_ID_MUSICS_BY_SEARCH;
/**
* Utility class to help on queue related tasks.
*/
public class QueueHelper {
private static final String TAG = "QueueHelper";
public static List<MediaSessionCompat.QueueItem> getPlayingQueue(String mediaId,
MusicProvider musicProvider) {
// extract the browsing hierarchy from the media ID:
String[] hierarchy = MediaIDHelper.getHierarchy(mediaId);
if (hierarchy.length != 2) {
Log.e(TAG, "Could not build a playing queue for this mediaId: " + mediaId);
return null;
}
String categoryType = hierarchy[0];
String categoryValue = hierarchy[1];
Log.d(TAG, "Creating playing queue for " + categoryType + ", " + categoryValue);
Iterable<MediaMetadataCompat> tracks = null;
// This sample only supports genre and by_search category types.
if (categoryType.equals(MEDIA_ID_MUSICS_BY_GENRE)) {
tracks = musicProvider.getMusicsByGenre(categoryValue);
} else if (categoryType.equals(MEDIA_ID_MUSICS_BY_SEARCH)) {
tracks = musicProvider.searchMusic(categoryValue);
}
if (tracks == null) {
Log.e(TAG, "Unrecognized category type: " + categoryType + " for mediaId " + mediaId);
return null;
}
return convertToQueue(tracks, hierarchy[0], hierarchy[1]);
}
public static List<MediaSessionCompat.QueueItem> getPlayingQueueFromSearch(String query,
MusicProvider musicProvider) {
Log.d(TAG, "Creating playing queue for musics from search " + query);
return convertToQueue(musicProvider.searchMusic(query), MEDIA_ID_MUSICS_BY_SEARCH, query);
}
public static int getMusicIndexOnQueue(Iterable<MediaSessionCompat.QueueItem> queue,
String mediaId) {
int index = 0;
for (MediaSessionCompat.QueueItem item : queue) {
if (mediaId.equals(item.getDescription().getMediaId())) {
return index;
}
index++;
}
return -1;
}
public static int getMusicIndexOnQueue(Iterable<MediaSessionCompat.QueueItem> queue,
long queueId) {
int index = 0;
for (MediaSessionCompat.QueueItem item : queue) {
if (queueId == item.getQueueId()) {
return index;
}
index++;
}
return -1;
}
private static List<MediaSessionCompat.QueueItem> convertToQueue(
Iterable<MediaMetadataCompat> tracks, String... categories) {
List<MediaSessionCompat.QueueItem> queue = new ArrayList<>();
int count = 0;
for (MediaMetadataCompat track : tracks) {
// We create a hierarchy-aware mediaID, so we know what the queue is about by looking
// at the QueueItem media IDs.
String hierarchyAwareMediaID = MediaIDHelper.createMediaID(
track.getDescription().getMediaId(), categories);
MediaMetadataCompat trackCopy = new MediaMetadataCompat.Builder(track)
.putString(MediaMetadataCompat.METADATA_KEY_MEDIA_ID, hierarchyAwareMediaID)
.build();
// We don't expect queues to change after created, so we use the item index as the
// queueId. Any other number unique in the queue would work.
MediaSessionCompat.QueueItem item = new MediaSessionCompat.QueueItem(
trackCopy.getDescription(), count++);
queue.add(item);
}
return queue;
}
/**
* Create a random queue. For simplicity sake, instead of a random queue, we create a
* queue using the first genre.
*
* @param musicProvider the provider used for fetching music.
* @return list containing {@link android.media.session.MediaSession.QueueItem}'s
*/
public static List<MediaSessionCompat.QueueItem> getRandomQueue(MusicProvider musicProvider) {
Iterator<String> genres = musicProvider.getGenres().iterator();
if (!genres.hasNext()) {
return Collections.emptyList();
}
String genre = genres.next();
Iterable<MediaMetadataCompat> tracks = musicProvider.getMusicsByGenre(genre);
return convertToQueue(tracks, MEDIA_ID_MUSICS_BY_GENRE, genre);
}
public static boolean isIndexPlayable(int index, List<MediaSessionCompat.QueueItem> queue) {
return (queue != null && index >= 0 && index < queue.size());
}
}