1 /*
2  * Copyright (C) 2013 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.example.android.supportv7.media;
18 
19 import android.content.Context;
20 import android.graphics.Bitmap;
21 import android.os.Build;
22 import android.support.v4.media.MediaMetadataCompat;
23 import android.support.v4.media.session.MediaSessionCompat;
24 import android.support.v4.media.session.PlaybackStateCompat;
25 import android.util.Log;
26 
27 import androidx.annotation.RequiresApi;
28 import androidx.mediarouter.media.MediaControlIntent;
29 import androidx.mediarouter.media.MediaRouter.RouteInfo;
30 
31 /**
32  * Abstraction of common playback operations of media items, such as play,
33  * seek, etc. Used by PlaybackManager as a backend to handle actual playback
34  * of media items.
35  *
36  * TODO: Introduce prepare() method and refactor subclasses accordingly.
37  */
38 public abstract class Player {
39     private static final String TAG = "SampleMediaRoutePlayer";
40     private static final boolean DEBUG = Log.isLoggable(TAG, Log.DEBUG);
41     protected static final int STATE_IDLE = 0;
42     protected static final int STATE_PREPARING_FOR_PLAY = 1;
43     protected static final int STATE_PREPARING_FOR_PAUSE = 2;
44     protected static final int STATE_READY = 3;
45     protected static final int STATE_PLAYING = 4;
46     protected static final int STATE_PAUSED = 5;
47 
48     private static final long PLAYBACK_ACTIONS = PlaybackStateCompat.ACTION_PAUSE
49             | PlaybackStateCompat.ACTION_PLAY;
50     private static final PlaybackStateCompat INIT_PLAYBACK_STATE = new PlaybackStateCompat.Builder()
51             .setState(PlaybackStateCompat.STATE_NONE, 0, .0f).build();
52 
53     protected Callback mCallback;
54     protected MediaSessionCompat mMediaSession;
55 
isRemotePlayback()56     public abstract boolean isRemotePlayback();
isQueuingSupported()57     public abstract boolean isQueuingSupported();
58 
connect(RouteInfo route)59     public abstract void connect(RouteInfo route);
release()60     public abstract void release();
61 
62     // basic operations that are always supported
play(final PlaylistItem item)63     public abstract void play(final PlaylistItem item);
seek(final PlaylistItem item)64     public abstract void seek(final PlaylistItem item);
getStatus(final PlaylistItem item, final boolean update)65     public abstract void getStatus(final PlaylistItem item, final boolean update);
pause()66     public abstract void pause();
resume()67     public abstract void resume();
stop()68     public abstract void stop();
69 
70     // advanced queuing (enqueue & remove) are only supported
71     // if isQueuingSupported() returns true
enqueue(final PlaylistItem item)72     public abstract void enqueue(final PlaylistItem item);
remove(String iid)73     public abstract PlaylistItem remove(String iid);
74 
takeSnapshot()75     public void takeSnapshot() {}
getSnapshot()76     public Bitmap getSnapshot() { return null; }
77 
78     /**
79      * presentation display
80      */
81     @RequiresApi(Build.VERSION_CODES.JELLY_BEAN_MR1)
updatePresentation()82     public void updatePresentation() {}
83 
setCallback(Callback callback)84     public void setCallback(Callback callback) {
85         mCallback = callback;
86     }
87 
create(Context context, RouteInfo route, MediaSessionCompat session)88     public static Player create(Context context, RouteInfo route, MediaSessionCompat session) {
89         Player player;
90         if (route != null && route.supportsControlCategory(
91                 MediaControlIntent.CATEGORY_REMOTE_PLAYBACK)) {
92             player = new RemotePlayer(context);
93         } else if (route != null) {
94             player = new LocalPlayer.SurfaceViewPlayer(context);
95         } else {
96             player = new LocalPlayer.OverlayPlayer(context);
97         }
98         player.setMediaSession(session);
99         player.initMediaSession();
100         player.connect(route);
101         return player;
102     }
103 
initMediaSession()104     protected void initMediaSession() {
105         if (mMediaSession == null) {
106             return;
107         }
108         mMediaSession.setMetadata(null);
109         mMediaSession.setPlaybackState(INIT_PLAYBACK_STATE);
110     }
111 
updateMetadata(PlaylistItem currentItem)112     protected void updateMetadata(PlaylistItem currentItem) {
113         if (mMediaSession == null) {
114             return;
115         }
116         if (DEBUG) {
117             Log.d(TAG, "Update metadata: currentItem=" + currentItem);
118         }
119         if (currentItem == null) {
120             mMediaSession.setMetadata(null);
121             return;
122         }
123         MediaMetadataCompat.Builder bob = new MediaMetadataCompat.Builder();
124         bob.putString(MediaMetadataCompat.METADATA_KEY_DISPLAY_TITLE, currentItem.getTitle());
125         bob.putString(MediaMetadataCompat.METADATA_KEY_DISPLAY_SUBTITLE, "Subtitle of the thing");
126         bob.putString(MediaMetadataCompat.METADATA_KEY_DISPLAY_DESCRIPTION,
127                 "Description of the thing");
128         bob.putBitmap(MediaMetadataCompat.METADATA_KEY_DISPLAY_ICON, getSnapshot());
129         mMediaSession.setMetadata(bob.build());
130     }
131 
publishState(int state)132     protected void publishState(int state) {
133         if (mMediaSession == null) {
134             return;
135         }
136         PlaybackStateCompat.Builder bob = new PlaybackStateCompat.Builder();
137         bob.setActions(PLAYBACK_ACTIONS);
138         switch (state) {
139             case STATE_PLAYING:
140                 bob.setState(PlaybackStateCompat.STATE_PLAYING, -1, 1);
141                 break;
142             case STATE_READY:
143             case STATE_PAUSED:
144                 bob.setState(PlaybackStateCompat.STATE_PAUSED, -1, 0);
145                 break;
146             case STATE_PREPARING_FOR_PLAY:
147             case STATE_PREPARING_FOR_PAUSE:
148                 bob.setState(PlaybackStateCompat.STATE_BUFFERING, -1, 0);
149                 break;
150             case STATE_IDLE:
151                 bob.setState(PlaybackStateCompat.STATE_STOPPED, -1, 0);
152                 break;
153         }
154         PlaybackStateCompat pbState = bob.build();
155         Log.d(TAG, "Setting state to " + pbState);
156         mMediaSession.setPlaybackState(pbState);
157         if (state != STATE_IDLE) {
158             mMediaSession.setActive(true);
159         } else {
160             mMediaSession.setActive(false);
161         }
162     }
163 
setMediaSession(MediaSessionCompat session)164     private void setMediaSession(MediaSessionCompat session) {
165         mMediaSession = session;
166     }
167 
168     public interface Callback {
onError()169         void onError();
onCompletion()170         void onCompletion();
onPlaylistChanged()171         void onPlaylistChanged();
onPlaylistReady()172         void onPlaylistReady();
173     }
174 }
175