xref: /frameworks/base/media/java/android/media/MediaPlayer2Impl.java

/*
 * Copyright 2018 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 android.media;

import android.annotation.CallbackExecutor;
import android.annotation.NonNull;
import android.annotation.Nullable;
import android.app.ActivityThread;
import android.content.ContentProvider;
import android.content.ContentResolver;
import android.content.Context;
import android.content.res.AssetFileDescriptor;
import android.net.Uri;
import android.os.Handler;
import android.os.HandlerThread;
import android.os.Looper;
import android.os.Message;
import android.os.Parcel;
import android.os.Parcelable;
import android.os.PersistableBundle;
import android.os.Process;
import android.os.PowerManager;
import android.os.SystemProperties;
import android.provider.Settings;
import android.system.ErrnoException;
import android.system.Os;
import android.system.OsConstants;
import android.util.Log;
import android.util.Pair;
import android.util.ArrayMap;
import android.view.Surface;
import android.view.SurfaceHolder;
import android.widget.VideoView;
import android.graphics.SurfaceTexture;
import android.media.SubtitleController.Anchor;
import android.media.SubtitleTrack.RenderingWidget;

import com.android.internal.annotations.GuardedBy;
import com.android.internal.util.Preconditions;

import dalvik.system.CloseGuard;

import libcore.io.IoBridge;
import libcore.io.Streams;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileDescriptor;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.lang.Runnable;
import java.lang.ref.WeakReference;
import java.net.CookieHandler;
import java.net.CookieManager;
import java.net.HttpCookie;
import java.net.HttpURLConnection;
import java.net.URL;
import java.nio.ByteOrder;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.BitSet;
import java.util.Collections;
import java.util.concurrent.Executor;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Scanner;
import java.util.Set;
import java.util.UUID;
import java.util.Vector;


/**
 * MediaPlayer2 class can be used to control playback
 * of audio/video files and streams. An example on how to use the methods in
 * this class can be found in {@link android.widget.VideoView}.
 *
 * <p>Topics covered here are:
 * <ol>
 * <li><a href="#StateDiagram">State Diagram</a>
 * <li><a href="#Valid_and_Invalid_States">Valid and Invalid States</a>
 * <li><a href="#Permissions">Permissions</a>
 * <li><a href="#Callbacks">Register informational and error callbacks</a>
 * </ol>
 *
 * <div class="special reference">
 * <h3>Developer Guides</h3>
 * <p>For more information about how to use MediaPlayer2, read the
 * <a href="{@docRoot}guide/topics/media/mediaplayer.html">Media Playback</a> developer guide.</p>
 * </div>
 *
 * <a name="StateDiagram"></a>
 * <h3>State Diagram</h3>
 *
 * <p>Playback control of audio/video files and streams is managed as a state
 * machine. The following diagram shows the life cycle and the states of a
 * MediaPlayer2 object driven by the supported playback control operations.
 * The ovals represent the states a MediaPlayer2 object may reside
 * in. The arcs represent the playback control operations that drive the object
 * state transition. There are two types of arcs. The arcs with a single arrow
 * head represent synchronous method calls, while those with
 * a double arrow head represent asynchronous method calls.</p>
 *
 * <p><img src="../../../images/mediaplayer_state_diagram.gif"
 *         alt="MediaPlayer State diagram"
 *         border="0" /></p>
 *
 * <p>From this state diagram, one can see that a MediaPlayer2 object has the
 *    following states:</p>
 * <ul>
 *     <li>When a MediaPlayer2 object is just created using <code>new</code> or
 *         after {@link #reset()} is called, it is in the <em>Idle</em> state; and after
 *         {@link #close()} is called, it is in the <em>End</em> state. Between these
 *         two states is the life cycle of the MediaPlayer2 object.
 *         <ul>
 *         <li>There is a subtle but important difference between a newly constructed
 *         MediaPlayer2 object and the MediaPlayer2 object after {@link #reset()}
 *         is called. It is a programming error to invoke methods such
 *         as {@link #getCurrentPosition()},
 *         {@link #getDuration()}, {@link #getVideoHeight()},
 *         {@link #getVideoWidth()}, {@link #setAudioAttributes(AudioAttributes)},
 *         {@link #setLooping(boolean)},
 *         {@link #setVolume(float, float)}, {@link #pause()}, {@link #play()},
 *         {@link #seekTo(long, int)}, {@link #prepare()} or
 *         {@link #prepareAsync()} in the <em>Idle</em> state for both cases. If any of these
 *         methods is called right after a MediaPlayer2 object is constructed,
 *         the user supplied callback method OnErrorListener.onError() won't be
 *         called by the internal player engine and the object state remains
 *         unchanged; but if these methods are called right after {@link #reset()},
 *         the user supplied callback method OnErrorListener.onError() will be
 *         invoked by the internal player engine and the object will be
 *         transfered to the <em>Error</em> state. </li>
 *         <li>It is also recommended that once
 *         a MediaPlayer2 object is no longer being used, call {@link #close()} immediately
 *         so that resources used by the internal player engine associated with the
 *         MediaPlayer2 object can be released immediately. Resource may include
 *         singleton resources such as hardware acceleration components and
 *         failure to call {@link #close()} may cause subsequent instances of
 *         MediaPlayer2 objects to fallback to software implementations or fail
 *         altogether. Once the MediaPlayer2
 *         object is in the <em>End</em> state, it can no longer be used and
 *         there is no way to bring it back to any other state. </li>
 *         <li>Furthermore,
 *         the MediaPlayer2 objects created using <code>new</code> is in the
 *         <em>Idle</em> state.
 *         </li>
 *         </ul>
 *         </li>
 *     <li>In general, some playback control operation may fail due to various
 *         reasons, such as unsupported audio/video format, poorly interleaved
 *         audio/video, resolution too high, streaming timeout, and the like.
 *         Thus, error reporting and recovery is an important concern under
 *         these circumstances. Sometimes, due to programming errors, invoking a playback
 *         control operation in an invalid state may also occur. Under all these
 *         error conditions, the internal player engine invokes a user supplied
 *         EventCallback.onError() method if an EventCallback has been
 *         registered beforehand via
 *         {@link #registerEventCallback(Executor, EventCallback)}.
 *         <ul>
 *         <li>It is important to note that once an error occurs, the
 *         MediaPlayer2 object enters the <em>Error</em> state (except as noted
 *         above), even if an error listener has not been registered by the application.</li>
 *         <li>In order to reuse a MediaPlayer2 object that is in the <em>
 *         Error</em> state and recover from the error,
 *         {@link #reset()} can be called to restore the object to its <em>Idle</em>
 *         state.</li>
 *         <li>It is good programming practice to have your application
 *         register a OnErrorListener to look out for error notifications from
 *         the internal player engine.</li>
 *         <li>IllegalStateException is
 *         thrown to prevent programming errors such as calling {@link #prepare()},
 *         {@link #prepareAsync()}, {@link #setDataSource(DataSourceDesc)}, or
 *         {@code setPlaylist} methods in an invalid state. </li>
 *         </ul>
 *         </li>
 *     <li>Calling
 *         {@link #setDataSource(DataSourceDesc)}, or
 *         {@code setPlaylist} transfers a
 *         MediaPlayer2 object in the <em>Idle</em> state to the
 *         <em>Initialized</em> state.
 *         <ul>
 *         <li>An IllegalStateException is thrown if
 *         setDataSource() or setPlaylist() is called in any other state.</li>
 *         <li>It is good programming
 *         practice to always look out for <code>IllegalArgumentException</code>
 *         and <code>IOException</code> that may be thrown from
 *         <code>setDataSource</code> and <code>setPlaylist</code> methods.</li>
 *         </ul>
 *         </li>
 *     <li>A MediaPlayer2 object must first enter the <em>Prepared</em> state
 *         before playback can be started.
 *         <ul>
 *         <li>There are two ways (synchronous vs.
 *         asynchronous) that the <em>Prepared</em> state can be reached:
 *         either a call to {@link #prepare()} (synchronous) which
 *         transfers the object to the <em>Prepared</em> state once the method call
 *         returns, or a call to {@link #prepareAsync()} (asynchronous) which
 *         first transfers the object to the <em>Preparing</em> state after the
 *         call returns (which occurs almost right way) while the internal
 *         player engine continues working on the rest of preparation work
 *         until the preparation work completes. When the preparation completes or when {@link #prepare()} call returns,
 *         the internal player engine then calls a user supplied callback method,
 *         onPrepared() of the EventCallback interface, if an
 *         EventCallback is registered beforehand via {@link
 *         #registerEventCallback(Executor, EventCallback)}.</li>
 *         <li>It is important to note that
 *         the <em>Preparing</em> state is a transient state, and the behavior
 *         of calling any method with side effect while a MediaPlayer2 object is
 *         in the <em>Preparing</em> state is undefined.</li>
 *         <li>An IllegalStateException is
 *         thrown if {@link #prepare()} or {@link #prepareAsync()} is called in
 *         any other state.</li>
 *         <li>While in the <em>Prepared</em> state, properties
 *         such as audio/sound volume, screenOnWhilePlaying, looping can be
 *         adjusted by invoking the corresponding set methods.</li>
 *         </ul>
 *         </li>
 *     <li>To start the playback, {@link #play()} must be called. After
 *         {@link #play()} returns successfully, the MediaPlayer2 object is in the
 *         <em>Started</em> state. {@link #isPlaying()} can be called to test
 *         whether the MediaPlayer2 object is in the <em>Started</em> state.
 *         <ul>
 *         <li>While in the <em>Started</em> state, the internal player engine calls
 *         a user supplied EventCallback.onBufferingUpdate() callback
 *         method if an EventCallback has been registered beforehand
 *         via {@link #registerEventCallback(Executor, EventCallback)}.
 *         This callback allows applications to keep track of the buffering status
 *         while streaming audio/video.</li>
 *         <li>Calling {@link #play()} has not effect
 *         on a MediaPlayer2 object that is already in the <em>Started</em> state.</li>
 *         </ul>
 *         </li>
 *     <li>Playback can be paused and stopped, and the current playback position
 *         can be adjusted. Playback can be paused via {@link #pause()}. When the call to
 *         {@link #pause()} returns, the MediaPlayer2 object enters the
 *         <em>Paused</em> state. Note that the transition from the <em>Started</em>
 *         state to the <em>Paused</em> state and vice versa happens
 *         asynchronously in the player engine. It may take some time before
 *         the state is updated in calls to {@link #isPlaying()}, and it can be
 *         a number of seconds in the case of streamed content.
 *         <ul>
 *         <li>Calling {@link #play()} to resume playback for a paused
 *         MediaPlayer2 object, and the resumed playback
 *         position is the same as where it was paused. When the call to
 *         {@link #play()} returns, the paused MediaPlayer2 object goes back to
 *         the <em>Started</em> state.</li>
 *         <li>Calling {@link #pause()} has no effect on
 *         a MediaPlayer2 object that is already in the <em>Paused</em> state.</li>
 *         </ul>
 *         </li>
 *     <li>The playback position can be adjusted with a call to
 *         {@link #seekTo(long, int)}.
 *         <ul>
 *         <li>Although the asynchronuous {@link #seekTo(long, int)}
 *         call returns right away, the actual seek operation may take a while to
 *         finish, especially for audio/video being streamed. When the actual
 *         seek operation completes, the internal player engine calls a user
 *         supplied EventCallback.onSeekComplete() if an EventCallback
 *         has been registered beforehand via
 *         {@link #registerEventCallback(Executor, EventCallback)}.</li>
 *         <li>Please
 *         note that {@link #seekTo(long, int)} can also be called in the other states,
 *         such as <em>Prepared</em>, <em>Paused</em> and <em>PlaybackCompleted
 *         </em> state. When {@link #seekTo(long, int)} is called in those states,
 *         one video frame will be displayed if the stream has video and the requested
 *         position is valid.
 *         </li>
 *         <li>Furthermore, the actual current playback position
 *         can be retrieved with a call to {@link #getCurrentPosition()}, which
 *         is helpful for applications such as a Music player that need to keep
 *         track of the playback progress.</li>
 *         </ul>
 *         </li>
 *     <li>When the playback reaches the end of stream, the playback completes.
 *         <ul>
 *         <li>If the looping mode was being set to <var>true</var>with
 *         {@link #setLooping(boolean)}, the MediaPlayer2 object shall remain in
 *         the <em>Started</em> state.</li>
 *         <li>If the looping mode was set to <var>false
 *         </var>, the player engine calls a user supplied callback method,
 *         EventCallback.onCompletion(), if an EventCallback is registered
 *         beforehand via {@link #registerEventCallback(Executor, EventCallback)}.
 *         The invoke of the callback signals that the object is now in the <em>
 *         PlaybackCompleted</em> state.</li>
 *         <li>While in the <em>PlaybackCompleted</em>
 *         state, calling {@link #play()} can restart the playback from the
 *         beginning of the audio/video source.</li>
 * </ul>
 *
 *
 * <a name="Valid_and_Invalid_States"></a>
 * <h3>Valid and invalid states</h3>
 *
 * <table border="0" cellspacing="0" cellpadding="0">
 * <tr><td>Method Name </p></td>
 *     <td>Valid Sates </p></td>
 *     <td>Invalid States </p></td>
 *     <td>Comments </p></td></tr>
 * <tr><td>attachAuxEffect </p></td>
 *     <td>{Initialized, Prepared, Started, Paused, Stopped, PlaybackCompleted} </p></td>
 *     <td>{Idle, Error} </p></td>
 *     <td>This method must be called after setDataSource or setPlaylist.
 *     Calling it does not change the object state. </p></td></tr>
 * <tr><td>getAudioSessionId </p></td>
 *     <td>any </p></td>
 *     <td>{} </p></td>
 *     <td>This method can be called in any state and calling it does not change
 *         the object state. </p></td></tr>
 * <tr><td>getCurrentPosition </p></td>
 *     <td>{Idle, Initialized, Prepared, Started, Paused, Stopped,
 *         PlaybackCompleted} </p></td>
 *     <td>{Error}</p></td>
 *     <td>Successful invoke of this method in a valid state does not change the
 *         state. Calling this method in an invalid state transfers the object
 *         to the <em>Error</em> state. </p></td></tr>
 * <tr><td>getDuration </p></td>
 *     <td>{Prepared, Started, Paused, Stopped, PlaybackCompleted} </p></td>
 *     <td>{Idle, Initialized, Error} </p></td>
 *     <td>Successful invoke of this method in a valid state does not change the
 *         state. Calling this method in an invalid state transfers the object
 *         to the <em>Error</em> state. </p></td></tr>
 * <tr><td>getVideoHeight </p></td>
 *     <td>{Idle, Initialized, Prepared, Started, Paused, Stopped,
 *         PlaybackCompleted}</p></td>
 *     <td>{Error}</p></td>
 *     <td>Successful invoke of this method in a valid state does not change the
 *         state. Calling this method in an invalid state transfers the object
 *         to the <em>Error</em> state.  </p></td></tr>
 * <tr><td>getVideoWidth </p></td>
 *     <td>{Idle, Initialized, Prepared, Started, Paused, Stopped,
 *         PlaybackCompleted}</p></td>
 *     <td>{Error}</p></td>
 *     <td>Successful invoke of this method in a valid state does not change
 *         the state. Calling this method in an invalid state transfers the
 *         object to the <em>Error</em> state. </p></td></tr>
 * <tr><td>isPlaying </p></td>
 *     <td>{Idle, Initialized, Prepared, Started, Paused, Stopped,
 *          PlaybackCompleted}</p></td>
 *     <td>{Error}</p></td>
 *     <td>Successful invoke of this method in a valid state does not change
 *         the state. Calling this method in an invalid state transfers the
 *         object to the <em>Error</em> state. </p></td></tr>
 * <tr><td>pause </p></td>
 *     <td>{Started, Paused, PlaybackCompleted}</p></td>
 *     <td>{Idle, Initialized, Prepared, Stopped, Error}</p></td>
 *     <td>Successful invoke of this method in a valid state transfers the
 *         object to the <em>Paused</em> state. Calling this method in an
 *         invalid state transfers the object to the <em>Error</em> state.</p></td></tr>
 * <tr><td>prepare </p></td>
 *     <td>{Initialized, Stopped} </p></td>
 *     <td>{Idle, Prepared, Started, Paused, PlaybackCompleted, Error} </p></td>
 *     <td>Successful invoke of this method in a valid state transfers the
 *         object to the <em>Prepared</em> state. Calling this method in an
 *         invalid state throws an IllegalStateException.</p></td></tr>
 * <tr><td>prepareAsync </p></td>
 *     <td>{Initialized, Stopped} </p></td>
 *     <td>{Idle, Prepared, Started, Paused, PlaybackCompleted, Error} </p></td>
 *     <td>Successful invoke of this method in a valid state transfers the
 *         object to the <em>Preparing</em> state. Calling this method in an
 *         invalid state throws an IllegalStateException.</p></td></tr>
 * <tr><td>release </p></td>
 *     <td>any </p></td>
 *     <td>{} </p></td>
 *     <td>After {@link #close()}, the object is no longer available. </p></td></tr>
 * <tr><td>reset </p></td>
 *     <td>{Idle, Initialized, Prepared, Started, Paused, Stopped,
 *         PlaybackCompleted, Error}</p></td>
 *     <td>{}</p></td>
 *     <td>After {@link #reset()}, the object is like being just created.</p></td></tr>
 * <tr><td>seekTo </p></td>
 *     <td>{Prepared, Started, Paused, PlaybackCompleted} </p></td>
 *     <td>{Idle, Initialized, Stopped, Error}</p></td>
 *     <td>Successful invoke of this method in a valid state does not change
 *         the state. Calling this method in an invalid state transfers the
 *         object to the <em>Error</em> state. </p></td></tr>
 * <tr><td>setAudioAttributes </p></td>
 *     <td>{Idle, Initialized, Stopped, Prepared, Started, Paused,
 *          PlaybackCompleted}</p></td>
 *     <td>{Error}</p></td>
 *     <td>Successful invoke of this method does not change the state. In order for the
 *         target audio attributes type to become effective, this method must be called before
 *         prepare() or prepareAsync().</p></td></tr>
 * <tr><td>setAudioSessionId </p></td>
 *     <td>{Idle} </p></td>
 *     <td>{Initialized, Prepared, Started, Paused, Stopped, PlaybackCompleted,
 *          Error} </p></td>
 *     <td>This method must be called in idle state as the audio session ID must be known before
 *         calling setDataSource or setPlaylist. Calling it does not change the object
 *         state. </p></td></tr>
 * <tr><td>setAudioStreamType (deprecated)</p></td>
 *     <td>{Idle, Initialized, Stopped, Prepared, Started, Paused,
 *          PlaybackCompleted}</p></td>
 *     <td>{Error}</p></td>
 *     <td>Successful invoke of this method does not change the state. In order for the
 *         target audio stream type to become effective, this method must be called before
 *         prepare() or prepareAsync().</p></td></tr>
 * <tr><td>setAuxEffectSendLevel </p></td>
 *     <td>any</p></td>
 *     <td>{} </p></td>
 *     <td>Calling this method does not change the object state. </p></td></tr>
 * <tr><td>setDataSource </p></td>
 *     <td>{Idle} </p></td>
 *     <td>{Initialized, Prepared, Started, Paused, Stopped, PlaybackCompleted,
 *          Error} </p></td>
 *     <td>Successful invoke of this method in a valid state transfers the
 *         object to the <em>Initialized</em> state. Calling this method in an
 *         invalid state throws an IllegalStateException.</p></td></tr>
 * <tr><td>setPlaylist </p></td>
 *     <td>{Idle} </p></td>
 *     <td>{Initialized, Prepared, Started, Paused, Stopped, PlaybackCompleted,
 *          Error} </p></td>
 *     <td>Successful invoke of this method in a valid state transfers the
 *         object to the <em>Initialized</em> state. Calling this method in an
 *         invalid state throws an IllegalStateException.</p></td></tr>
 * <tr><td>setDisplay </p></td>
 *     <td>any </p></td>
 *     <td>{} </p></td>
 *     <td>This method can be called in any state and calling it does not change
 *         the object state. </p></td></tr>
 * <tr><td>setSurface </p></td>
 *     <td>any </p></td>
 *     <td>{} </p></td>
 *     <td>This method can be called in any state and calling it does not change
 *         the object state. </p></td></tr>
 * <tr><td>setVideoScalingMode </p></td>
 *     <td>{Initialized, Prepared, Started, Paused, Stopped, PlaybackCompleted} </p></td>
 *     <td>{Idle, Error}</p></td>
 *     <td>Successful invoke of this method does not change the state.</p></td></tr>
 * <tr><td>setLooping </p></td>
 *     <td>{Idle, Initialized, Stopped, Prepared, Started, Paused,
 *         PlaybackCompleted}</p></td>
 *     <td>{Error}</p></td>
 *     <td>Successful invoke of this method in a valid state does not change
 *         the state. Calling this method in an
 *         invalid state transfers the object to the <em>Error</em> state.</p></td></tr>
 * <tr><td>isLooping </p></td>
 *     <td>any </p></td>
 *     <td>{} </p></td>
 *     <td>This method can be called in any state and calling it does not change
 *         the object state. </p></td></tr>
 * <tr><td>registerDrmEventCallback </p></td>
 *     <td>any </p></td>
 *     <td>{} </p></td>
 *     <td>This method can be called in any state and calling it does not change
 *         the object state. </p></td></tr>
 * <tr><td>registerEventCallback </p></td>
 *     <td>any </p></td>
 *     <td>{} </p></td>
 *     <td>This method can be called in any state and calling it does not change
 *         the object state. </p></td></tr>
 * <tr><td>setPlaybackParams</p></td>
 *     <td>{Initialized, Prepared, Started, Paused, PlaybackCompleted, Error}</p></td>
 *     <td>{Idle, Stopped} </p></td>
 *     <td>This method will change state in some cases, depending on when it's called.
 *         </p></td></tr>
 * <tr><td>setScreenOnWhilePlaying</></td>
 *     <td>any </p></td>
 *     <td>{} </p></td>
 *     <td>This method can be called in any state and calling it does not change
 *         the object state.  </p></td></tr>
 * <tr><td>setVolume </p></td>
 *     <td>{Idle, Initialized, Stopped, Prepared, Started, Paused,
 *          PlaybackCompleted}</p></td>
 *     <td>{Error}</p></td>
 *     <td>Successful invoke of this method does not change the state.
 * <tr><td>setWakeMode </p></td>
 *     <td>any </p></td>
 *     <td>{} </p></td>
 *     <td>This method can be called in any state and calling it does not change
 *         the object state.</p></td></tr>
 * <tr><td>start </p></td>
 *     <td>{Prepared, Started, Paused, PlaybackCompleted}</p></td>
 *     <td>{Idle, Initialized, Stopped, Error}</p></td>
 *     <td>Successful invoke of this method in a valid state transfers the
 *         object to the <em>Started</em> state. Calling this method in an
 *         invalid state transfers the object to the <em>Error</em> state.</p></td></tr>
 * <tr><td>stop </p></td>
 *     <td>{Prepared, Started, Stopped, Paused, PlaybackCompleted}</p></td>
 *     <td>{Idle, Initialized, Error}</p></td>
 *     <td>Successful invoke of this method in a valid state transfers the
 *         object to the <em>Stopped</em> state. Calling this method in an
 *         invalid state transfers the object to the <em>Error</em> state.</p></td></tr>
 * <tr><td>getTrackInfo </p></td>
 *     <td>{Prepared, Started, Stopped, Paused, PlaybackCompleted}</p></td>
 *     <td>{Idle, Initialized, Error}</p></td>
 *     <td>Successful invoke of this method does not change the state.</p></td></tr>
 * <tr><td>addTimedTextSource </p></td>
 *     <td>{Prepared, Started, Stopped, Paused, PlaybackCompleted}</p></td>
 *     <td>{Idle, Initialized, Error}</p></td>
 *     <td>Successful invoke of this method does not change the state.</p></td></tr>
 * <tr><td>selectTrack </p></td>
 *     <td>{Prepared, Started, Stopped, Paused, PlaybackCompleted}</p></td>
 *     <td>{Idle, Initialized, Error}</p></td>
 *     <td>Successful invoke of this method does not change the state.</p></td></tr>
 * <tr><td>deselectTrack </p></td>
 *     <td>{Prepared, Started, Stopped, Paused, PlaybackCompleted}</p></td>
 *     <td>{Idle, Initialized, Error}</p></td>
 *     <td>Successful invoke of this method does not change the state.</p></td></tr>
 *
 * </table>
 *
 * <a name="Permissions"></a>
 * <h3>Permissions</h3>
 * <p>One may need to declare a corresponding WAKE_LOCK permission {@link
 * android.R.styleable#AndroidManifestUsesPermission &lt;uses-permission&gt;}
 * element.
 *
 * <p>This class requires the {@link android.Manifest.permission#INTERNET} permission
 * when used with network-based content.
 *
 * <a name="Callbacks"></a>
 * <h3>Callbacks</h3>
 * <p>Applications may want to register for informational and error
 * events in order to be informed of some internal state update and
 * possible runtime errors during playback or streaming. Registration for
 * these events is done by properly setting the appropriate listeners (via calls
 * to
 * {@link #registerEventCallback(Executor, EventCallback)},
 * {@link #registerDrmEventCallback(Executor, DrmEventCallback)}).
 * In order to receive the respective callback
 * associated with these listeners, applications are required to create
 * MediaPlayer2 objects on a thread with its own Looper running (main UI
 * thread by default has a Looper running).
 *
 * @hide
 */
public final class MediaPlayer2Impl extends MediaPlayer2 {
    static {
        System.loadLibrary("media2_jni");
        native_init();
    }

    private final static String TAG = "MediaPlayer2Impl";

    private long mNativeContext; // accessed by native methods
    private long mNativeSurfaceTexture;  // accessed by native methods
    private int mListenerContext; // accessed by native methods
    private SurfaceHolder mSurfaceHolder;
    private EventHandler mEventHandler;
    private PowerManager.WakeLock mWakeLock = null;
    private boolean mScreenOnWhilePlaying;
    private boolean mStayAwake;
    private int mStreamType = AudioManager.USE_DEFAULT_STREAM_TYPE;
    private int mUsage = -1;
    private boolean mBypassInterruptionPolicy;
    private final CloseGuard mGuard = CloseGuard.get();

    private List<DataSourceDesc> mPlaylist;
    private int mPLCurrentIndex = 0;
    private int mPLNextIndex = -1;
    private int mLoopingMode = LOOPING_MODE_NONE;

    // Modular DRM
    private UUID mDrmUUID;
    private final Object mDrmLock = new Object();
    private DrmInfoImpl mDrmInfoImpl;
    private MediaDrm mDrmObj;
    private byte[] mDrmSessionId;
    private boolean mDrmInfoResolved;
    private boolean mActiveDrmScheme;
    private boolean mDrmConfigAllowed;
    private boolean mDrmProvisioningInProgress;
    private boolean mPrepareDrmInProgress;
    private ProvisioningThread mDrmProvisioningThread;

    /**
     * Default constructor.
     * <p>When done with the MediaPlayer2Impl, you should call  {@link #close()},
     * to free the resources. If not released, too many MediaPlayer2Impl instances may
     * result in an exception.</p>
     */
    public MediaPlayer2Impl() {
        Looper looper;
        if ((looper = Looper.myLooper()) != null) {
            mEventHandler = new EventHandler(this, looper);
        } else if ((looper = Looper.getMainLooper()) != null) {
            mEventHandler = new EventHandler(this, looper);
        } else {
            mEventHandler = null;
        }

        mTimeProvider = new TimeProvider(this);
        mOpenSubtitleSources = new Vector<InputStream>();
        mGuard.open("close");

        /* Native setup requires a weak reference to our object.
         * It's easier to create it here than in C++.
         */
        native_setup(new WeakReference<MediaPlayer2Impl>(this));
    }

    /*
     * Update the MediaPlayer2Impl SurfaceTexture.
     * Call after setting a new display surface.
     */
    private native void _setVideoSurface(Surface surface);

    /* Do not change these values (starting with INVOKE_ID) without updating
     * their counterparts in include/media/mediaplayer2.h!
     */
    private static final int INVOKE_ID_GET_TRACK_INFO = 1;
    private static final int INVOKE_ID_ADD_EXTERNAL_SOURCE = 2;
    private static final int INVOKE_ID_ADD_EXTERNAL_SOURCE_FD = 3;
    private static final int INVOKE_ID_SELECT_TRACK = 4;
    private static final int INVOKE_ID_DESELECT_TRACK = 5;
    private static final int INVOKE_ID_SET_VIDEO_SCALE_MODE = 6;
    private static final int INVOKE_ID_GET_SELECTED_TRACK = 7;

    /**
     * Create a request parcel which can be routed to the native media
     * player using {@link #invoke(Parcel, Parcel)}. The Parcel
     * returned has the proper InterfaceToken set. The caller should
     * not overwrite that token, i.e it can only append data to the
     * Parcel.
     *
     * @return A parcel suitable to hold a request for the native
     * player.
     * {@hide}
     */
    @Override
    public Parcel newRequest() {
        Parcel parcel = Parcel.obtain();
        return parcel;
    }

    /**
     * Invoke a generic method on the native player using opaque
     * parcels for the request and reply. Both payloads' format is a
     * convention between the java caller and the native player.
     * Must be called after setDataSource or setPlaylist to make sure a native player
     * exists. On failure, a RuntimeException is thrown.
     *
     * @param request Parcel with the data for the extension. The
     * caller must use {@link #newRequest()} to get one.
     *
     * @param reply Output parcel with the data returned by the
     * native player.
     * {@hide}
     */
    @Override
    public void invoke(Parcel request, Parcel reply) {
        int retcode = native_invoke(request, reply);
        reply.setDataPosition(0);
        if (retcode != 0) {
            throw new RuntimeException("failure code: " + retcode);
        }
    }

    /**
     * Sets the {@link SurfaceHolder} to use for displaying the video
     * portion of the media.
     *
     * Either a surface holder or surface must be set if a display or video sink
     * is needed.  Not calling this method or {@link #setSurface(Surface)}
     * when playing back a video will result in only the audio track being played.
     * A null surface holder or surface will result in only the audio track being
     * played.
     *
     * @param sh the SurfaceHolder to use for video display
     * @throws IllegalStateException if the internal player engine has not been
     * initialized or has been released.
     * @hide
     */
    @Override
    public void setDisplay(SurfaceHolder sh) {
        mSurfaceHolder = sh;
        Surface surface;
        if (sh != null) {
            surface = sh.getSurface();
        } else {
            surface = null;
        }
        _setVideoSurface(surface);
        updateSurfaceScreenOn();
    }

    /**
     * Sets the {@link Surface} to be used as the sink for the video portion of
     * the media. This is similar to {@link #setDisplay(SurfaceHolder)}, but
     * does not support {@link #setScreenOnWhilePlaying(boolean)}.  Setting a
     * Surface will un-set any Surface or SurfaceHolder that was previously set.
     * A null surface will result in only the audio track being played.
     *
     * If the Surface sends frames to a {@link SurfaceTexture}, the timestamps
     * returned from {@link SurfaceTexture#getTimestamp()} will have an
     * unspecified zero point.  These timestamps cannot be directly compared
     * between different media sources, different instances of the same media
     * source, or multiple runs of the same program.  The timestamp is normally
     * monotonically increasing and is unaffected by time-of-day adjustments,
     * but it is reset when the position is set.
     *
     * @param surface The {@link Surface} to be used for the video portion of
     * the media.
     * @throws IllegalStateException if the internal player engine has not been
     * initialized or has been released.
     */
    @Override
    public void setSurface(Surface surface) {
        if (mScreenOnWhilePlaying && surface != null) {
            Log.w(TAG, "setScreenOnWhilePlaying(true) is ineffective for Surface");
        }
        mSurfaceHolder = null;
        _setVideoSurface(surface);
        updateSurfaceScreenOn();
    }

    /**
     * Sets video scaling mode. To make the target video scaling mode
     * effective during playback, this method must be called after
     * data source is set. If not called, the default video
     * scaling mode is {@link #VIDEO_SCALING_MODE_SCALE_TO_FIT}.
     *
     * <p> The supported video scaling modes are:
     * <ul>
     * <li> {@link #VIDEO_SCALING_MODE_SCALE_TO_FIT}
     * <li> {@link #VIDEO_SCALING_MODE_SCALE_TO_FIT_WITH_CROPPING}
     * </ul>
     *
     * @param mode target video scaling mode. Must be one of the supported
     * video scaling modes; otherwise, IllegalArgumentException will be thrown.
     *
     * @see MediaPlayer2#VIDEO_SCALING_MODE_SCALE_TO_FIT
     * @see MediaPlayer2#VIDEO_SCALING_MODE_SCALE_TO_FIT_WITH_CROPPING
     * @hide
     */
    @Override
    public void setVideoScalingMode(int mode) {
        if (!isVideoScalingModeSupported(mode)) {
            final String msg = "Scaling mode " + mode + " is not supported";
            throw new IllegalArgumentException(msg);
        }
        Parcel request = Parcel.obtain();
        Parcel reply = Parcel.obtain();
        try {
            request.writeInt(INVOKE_ID_SET_VIDEO_SCALE_MODE);
            request.writeInt(mode);
            invoke(request, reply);
        } finally {
            request.recycle();
            reply.recycle();
        }
    }

    /**
     * Discards all pending commands.
     */
    @Override
    public void clearPendingCommands() {
    }

    /**
     * Sets the data source as described by a DataSourceDesc.
     *
     * @param dsd the descriptor of data source you want to play
     * @throws IllegalStateException if it is called in an invalid state
     * @throws NullPointerException if dsd is null
     */
    @Override
    public void setDataSource(@NonNull DataSourceDesc dsd) throws IOException {
        Preconditions.checkNotNull(dsd, "the DataSourceDesc cannot be null");
        mPlaylist = Collections.synchronizedList(new ArrayList<DataSourceDesc>(1));
        mPlaylist.add(dsd);
        mPLCurrentIndex = 0;
        setDataSourcePriv(dsd);
    }

    /**
     * Gets the current data source as described by a DataSourceDesc.
     *
     * @return the current DataSourceDesc
     */
    @Override
    public DataSourceDesc getCurrentDataSource() {
        if (mPlaylist == null) {
            return null;
        }
        return mPlaylist.get(mPLCurrentIndex);
    }

    /**
     * Sets the play list.
     *
     * If startIndex falls outside play list range, it will be clamped to the nearest index
     * in the play list.
     *
     * @param pl the play list of data source you want to play
     * @param startIndex the index of the DataSourceDesc in the play list you want to play first
     * @throws IllegalStateException if it is called in an invalid state
     * @throws IllegalArgumentException if pl is null or empty, or pl contains null DataSourceDesc
     */
    @Override
    public void setPlaylist(@NonNull List<DataSourceDesc> pl, int startIndex)
            throws IOException {
        if (pl == null || pl.size() == 0) {
            throw new IllegalArgumentException("play list cannot be null or empty.");
        }
        HashSet ids = new HashSet(pl.size());
        for (DataSourceDesc dsd : pl) {
            if (dsd == null) {
                throw new IllegalArgumentException("DataSourceDesc in play list cannot be null.");
            }
            if (ids.add(dsd.getId()) == false) {
                throw new IllegalArgumentException("DataSourceDesc Id in play list should be unique.");
            }
        }

        if (startIndex < 0) {
            startIndex = 0;
        } else if (startIndex >= pl.size()) {
            startIndex = pl.size() - 1;
        }

        mPlaylist = Collections.synchronizedList(new ArrayList(pl));
        mPLCurrentIndex = startIndex;
        setDataSourcePriv(mPlaylist.get(startIndex));
        // TODO: handle the preparation of next source in the play list.
        // It should be processed after current source is prepared.
    }

    /**
     * Gets a copy of the play list.
     *
     * @return a copy of the play list used by {@link MediaPlayer2}
     */
    @Override
    public List<DataSourceDesc> getPlaylist() {
        if (mPlaylist == null) {
            return null;
        }
        return new ArrayList(mPlaylist);
    }

    /**
     * Sets the index of current DataSourceDesc in the play list to be played.
     *
     * @param index the index of DataSourceDesc in the play list you want to play
     * @throws IllegalArgumentException if the play list is null
     * @throws NullPointerException if index is outside play list range
     */
    @Override
    public void setCurrentPlaylistItem(int index) {
        if (mPlaylist == null) {
            throw new IllegalArgumentException("play list has not been set yet.");
        }
        if (index < 0 || index >= mPlaylist.size()) {
            throw new IndexOutOfBoundsException("index is out of play list range.");
        }

        if (index == mPLCurrentIndex) {
            return;
        }

        // TODO: in playing state, stop current source and start to play source of index.
        mPLCurrentIndex = index;
    }

    /**
     * Sets the index of next-to-be-played DataSourceDesc in the play list.
     *
     * @param index the index of next-to-be-played DataSourceDesc in the play list
     * @throws IllegalArgumentException if the play list is null
     * @throws NullPointerException if index is outside play list range
     */
    @Override
    public void setNextPlaylistItem(int index) {
        if (mPlaylist == null) {
            throw new IllegalArgumentException("play list has not been set yet.");
        }
        if (index < 0 || index >= mPlaylist.size()) {
            throw new IndexOutOfBoundsException("index is out of play list range.");
        }

        if (index == mPLNextIndex) {
            return;
        }

        // TODO: prepare the new next-to-be-played DataSourceDesc
        mPLNextIndex = index;
    }

    /**
     * Gets the current index of play list.
     *
     * @return the index of the current DataSourceDesc in the play list
     */
    @Override
    public int getCurrentPlaylistItemIndex() {
        return mPLCurrentIndex;
    }

    /**
     * Sets the looping mode of the play list.
     * The mode shall be one of {@link #LOOPING_MODE_NONE}, {@link #LOOPING_MODE_FULL},
     * {@link #LOOPING_MODE_SINGLE}, {@link #LOOPING_MODE_SHUFFLE}.
     *
     * @param mode the mode in which the play list will be played
     * @throws IllegalArgumentException if mode is not supported
     */
    @Override
    public void setLoopingMode(@LoopingMode int mode) {
        if (mode != LOOPING_MODE_NONE
            && mode != LOOPING_MODE_FULL
            && mode != LOOPING_MODE_SINGLE
            && mode != LOOPING_MODE_SHUFFLE) {
            throw new IllegalArgumentException("mode is not supported.");
        }
        mLoopingMode = mode;
        if (mPlaylist == null) {
            return;
        }

        // TODO: handle the new mode if necessary.
    }

    /**
     * Gets the looping mode of play list.
     *
     * @return the looping mode of the play list
     */
    @Override
    public int getLoopingMode() {
        return mPLCurrentIndex;
    }

    /**
     * Moves the DataSourceDesc at indexFrom in the play list to indexTo.
     *
     * @throws IllegalArgumentException if the play list is null
     * @throws IndexOutOfBoundsException if indexFrom or indexTo is outside play list range
     */
    @Override
    public void movePlaylistItem(int indexFrom, int indexTo) {
        if (mPlaylist == null) {
            throw new IllegalArgumentException("play list has not been set yet.");
        }
        // TODO: move the DataSourceDesc from indexFrom to indexTo.
    }

    /**
     * Removes the DataSourceDesc at index in the play list.
     *
     * If index is same as the current index of the play list, current DataSourceDesc
     * will be stopped and playback moves to next source in the list.
     *
     * @return the removed DataSourceDesc at index in the play list
     * @throws IllegalArgumentException if the play list is null
     * @throws IndexOutOfBoundsException if index is outside play list range
     */
    @Override
    public DataSourceDesc removePlaylistItem(int index) {
        if (mPlaylist == null) {
            throw new IllegalArgumentException("play list has not been set yet.");
        }

        DataSourceDesc oldDsd = mPlaylist.remove(index);
        // TODO: if index == mPLCurrentIndex, stop current source and move to next one.
        // if index == mPLNextIndex, prepare the new next-to-be-played source.
        return oldDsd;
    }

    /**
     * Inserts the DataSourceDesc to the play list at position index.
     *
     * This will not change the DataSourceDesc currently being played.
     * If index is less than or equal to the current index of the play list,
     * the current index of the play list will be incremented correspondingly.
     *
     * @param index the index you want to add dsd to the play list
     * @param dsd the descriptor of data source you want to add to the play list
     * @throws IndexOutOfBoundsException if index is outside play list range
     * @throws NullPointerException if dsd is null
     */
    @Override
    public void addPlaylistItem(int index, DataSourceDesc dsd) {
        Preconditions.checkNotNull(dsd, "the DataSourceDesc cannot be null");

        if (mPlaylist == null) {
            if (index == 0) {
                mPlaylist = Collections.synchronizedList(new ArrayList<DataSourceDesc>());
                mPlaylist.add(dsd);
                mPLCurrentIndex = 0;
                return;
            }
            throw new IllegalArgumentException("index should be 0 for first DataSourceDesc.");
        }

        long id = dsd.getId();
        for (DataSourceDesc pldsd : mPlaylist) {
            if (id == pldsd.getId()) {
                throw new IllegalArgumentException("Id of dsd already exists in the play list.");
            }
        }

        mPlaylist.add(index, dsd);
        if (index <= mPLCurrentIndex) {
            ++mPLCurrentIndex;
        }
    }

    /**
     * replaces the DataSourceDesc at index in the play list with given dsd.
     *
     * When index is same as the current index of the play list, the current source
     * will be stopped and the new source will be played, except that if new
     * and old source only differ on end position and current media position is
     * smaller then the new end position.
     *
     * This will not change the DataSourceDesc currently being played.
     * If index is less than or equal to the current index of the play list,
     * the current index of the play list will be incremented correspondingly.
     *
     * @param index the index you want to add dsd to the play list
     * @param dsd the descriptor of data source you want to add to the play list
     * @throws IndexOutOfBoundsException if index is outside play list range
     * @throws NullPointerException if dsd is null
     */
    @Override
    public DataSourceDesc editPlaylistItem(int index, DataSourceDesc dsd) {
        Preconditions.checkNotNull(dsd, "the DataSourceDesc cannot be null");
        Preconditions.checkNotNull(mPlaylist, "the play list cannot be null");

        long id = dsd.getId();
        for (int i = 0; i < mPlaylist.size(); ++i) {
            if (i == index) {
                continue;
            }
            if (id == mPlaylist.get(i).getId()) {
                throw new IllegalArgumentException("Id of dsd already exists in the play list.");
            }
        }

        // TODO: if needed, stop playback of current source, and start new dsd.
        DataSourceDesc oldDsd = mPlaylist.set(index, dsd);
        return mPlaylist.set(index, dsd);
    }

    private void setDataSourcePriv(@NonNull DataSourceDesc dsd) throws IOException {
        Preconditions.checkNotNull(dsd, "the DataSourceDesc cannot be null");

        switch (dsd.getType()) {
            case DataSourceDesc.TYPE_CALLBACK:
                setDataSourcePriv(dsd.getId(),
                                  dsd.getMedia2DataSource());
                break;

            case DataSourceDesc.TYPE_FD:
                setDataSourcePriv(dsd.getId(),
                                  dsd.getFileDescriptor(),
                                  dsd.getFileDescriptorOffset(),
                                  dsd.getFileDescriptorLength());
                break;

            case DataSourceDesc.TYPE_URI:
                setDataSourcePriv(dsd.getId(),
                                  dsd.getUriContext(),
                                  dsd.getUri(),
                                  dsd.getUriHeaders(),
                                  dsd.getUriCookies());
                break;

            default:
                break;
        }
    }

    /**
     * To provide cookies for the subsequent HTTP requests, you can install your own default cookie
     * handler and use other variants of setDataSource APIs instead. Alternatively, you can use
     * this API to pass the cookies as a list of HttpCookie. If the app has not installed
     * a CookieHandler already, this API creates a CookieManager and populates its CookieStore with
     * the provided cookies. If the app has installed its own handler already, this API requires the
     * handler to be of CookieManager type such that the API can update the manager’s CookieStore.
     *
     * <p><strong>Note</strong> that the cross domain redirection is allowed by default,
     * but that can be changed with key/value pairs through the headers parameter with
     * "android-allow-cross-domain-redirect" as the key and "0" or "1" as the value to
     * disallow or allow cross domain redirection.
     *
     * @throws IllegalArgumentException if cookies are provided and the installed handler is not
     *                                  a CookieManager
     * @throws IllegalStateException    if it is called in an invalid state
     * @throws NullPointerException     if context or uri is null
     * @throws IOException              if uri has a file scheme and an I/O error occurs
     */
    private void setDataSourcePriv(long srcId, @NonNull Context context, @NonNull Uri uri,
            @Nullable Map<String, String> headers, @Nullable List<HttpCookie> cookies)
            throws IOException {
        if (context == null) {
            throw new NullPointerException("context param can not be null.");
        }

        if (uri == null) {
            throw new NullPointerException("uri param can not be null.");
        }

        if (cookies != null) {
            CookieHandler cookieHandler = CookieHandler.getDefault();
            if (cookieHandler != null && !(cookieHandler instanceof CookieManager)) {
                throw new IllegalArgumentException("The cookie handler has to be of CookieManager "
                        + "type when cookies are provided.");
            }
        }

        // The context and URI usually belong to the calling user. Get a resolver for that user
        // and strip out the userId from the URI if present.
        final ContentResolver resolver = context.getContentResolver();
        final String scheme = uri.getScheme();
        final String authority = ContentProvider.getAuthorityWithoutUserId(uri.getAuthority());
        if (ContentResolver.SCHEME_FILE.equals(scheme)) {
            setDataSourcePriv(srcId, uri.getPath(), null, null);
            return;
        } else if (ContentResolver.SCHEME_CONTENT.equals(scheme)
                && Settings.AUTHORITY.equals(authority)) {
            // Try cached ringtone first since the actual provider may not be
            // encryption aware, or it may be stored on CE media storage
            final int type = RingtoneManager.getDefaultType(uri);
            final Uri cacheUri = RingtoneManager.getCacheForType(type, context.getUserId());
            final Uri actualUri = RingtoneManager.getActualDefaultRingtoneUri(context, type);
            if (attemptDataSource(srcId, resolver, cacheUri)) {
                return;
            } else if (attemptDataSource(srcId, resolver, actualUri)) {
                return;
            } else {
                setDataSourcePriv(srcId, uri.toString(), headers, cookies);
            }
        } else {
            // Try requested Uri locally first, or fallback to media server
            if (attemptDataSource(srcId, resolver, uri)) {
                return;
            } else {
                setDataSourcePriv(srcId, uri.toString(), headers, cookies);
            }
        }
    }

    private boolean attemptDataSource(long srcId, ContentResolver resolver, Uri uri) {
        try (AssetFileDescriptor afd = resolver.openAssetFileDescriptor(uri, "r")) {
            if (afd.getDeclaredLength() < 0) {
                setDataSourcePriv(srcId, afd.getFileDescriptor(), 0, DataSourceDesc.LONG_MAX);
            } else {
                setDataSourcePriv(srcId,
                                  afd.getFileDescriptor(),
                                  afd.getStartOffset(),
                                  afd.getDeclaredLength());
            }
            return true;
        } catch (NullPointerException | SecurityException | IOException ex) {
            Log.w(TAG, "Couldn't open " + uri + ": " + ex);
            return false;
        }
    }

    private void setDataSourcePriv(
            long srcId, String path, Map<String, String> headers, List<HttpCookie> cookies)
            throws IOException, IllegalArgumentException, SecurityException, IllegalStateException
    {
        String[] keys = null;
        String[] values = null;

        if (headers != null) {
            keys = new String[headers.size()];
            values = new String[headers.size()];

            int i = 0;
            for (Map.Entry<String, String> entry: headers.entrySet()) {
                keys[i] = entry.getKey();
                values[i] = entry.getValue();
                ++i;
            }
        }
        setDataSourcePriv(srcId, path, keys, values, cookies);
    }

    private void setDataSourcePriv(long srcId, String path, String[] keys, String[] values,
            List<HttpCookie> cookies)
            throws IOException, IllegalArgumentException, SecurityException, IllegalStateException {
        final Uri uri = Uri.parse(path);
        final String scheme = uri.getScheme();
        if ("file".equals(scheme)) {
            path = uri.getPath();
        } else if (scheme != null) {
            // handle non-file sources
            nativeSetDataSource(
                Media2HTTPService.createHTTPService(path, cookies),
                path,
                keys,
                values);
            return;
        }

        final File file = new File(path);
        if (file.exists()) {
            FileInputStream is = new FileInputStream(file);
            FileDescriptor fd = is.getFD();
            setDataSourcePriv(srcId, fd, 0, DataSourceDesc.LONG_MAX);
            is.close();
        } else {
            throw new IOException("setDataSourcePriv failed.");
        }
    }

    private native void nativeSetDataSource(
        Media2HTTPService httpService, String path, String[] keys, String[] values)
        throws IOException, IllegalArgumentException, SecurityException, IllegalStateException;

    /**
     * Sets the data source (FileDescriptor) to use. The FileDescriptor must be
     * seekable (N.B. a LocalSocket is not seekable). It is the caller's responsibility
     * to close the file descriptor. It is safe to do so as soon as this call returns.
     *
     * @throws IllegalStateException if it is called in an invalid state
     * @throws IllegalArgumentException if fd is not a valid FileDescriptor
     * @throws IOException if fd can not be read
     */
    private void setDataSourcePriv(long srcId, FileDescriptor fd, long offset, long length)
            throws IOException {
        _setDataSource(fd, offset, length);
    }

    private native void _setDataSource(FileDescriptor fd, long offset, long length)
            throws IOException;

    /**
     * @throws IllegalStateException if it is called in an invalid state
     * @throws IllegalArgumentException if dataSource is not a valid Media2DataSource
     */
    private void setDataSourcePriv(long srcId, Media2DataSource dataSource) {
        _setDataSource(dataSource);
    }

    private native void _setDataSource(Media2DataSource dataSource);

    /**
     * Prepares the player for playback, synchronously.
     *
     * After setting the datasource and the display surface, you need to either
     * call prepare() or prepareAsync(). For files, it is OK to call prepare(),
     * which blocks until MediaPlayer2 is ready for playback.
     *
     * @throws IOException if source can not be accessed
     * @throws IllegalStateException if it is called in an invalid state
     * @hide
     */
    @Override
    public void prepare() throws IOException {
        _prepare();
        scanInternalSubtitleTracks();

        // DrmInfo, if any, has been resolved by now.
        synchronized (mDrmLock) {
            mDrmInfoResolved = true;
        }
    }

    private native void _prepare() throws IOException, IllegalStateException;

    /**
     * Prepares the player for playback, asynchronously.
     *
     * After setting the datasource and the display surface, you need to either
     * call prepare() or prepareAsync(). For streams, you should call prepareAsync(),
     * which returns immediately, rather than blocking until enough data has been
     * buffered.
     *
     * @throws IllegalStateException if it is called in an invalid state
     */
    @Override
    public native void prepareAsync();

    /**
     * Starts or resumes playback. If playback had previously been paused,
     * playback will continue from where it was paused. If playback had
     * been stopped, or never started before, playback will start at the
     * beginning.
     *
     * @throws IllegalStateException if it is called in an invalid state
     */
    @Override
    public void play() {
        stayAwake(true);
        _start();
    }

    private native void _start() throws IllegalStateException;


    private int getAudioStreamType() {
        if (mStreamType == AudioManager.USE_DEFAULT_STREAM_TYPE) {
            mStreamType = _getAudioStreamType();
        }
        return mStreamType;
    }

    private native int _getAudioStreamType() throws IllegalStateException;

    /**
     * Stops playback after playback has been started or paused.
     *
     * @throws IllegalStateException if the internal player engine has not been
     * initialized.
     * #hide
     */
    @Override
    public void stop() {
        stayAwake(false);
        _stop();
    }

    private native void _stop() throws IllegalStateException;

    /**
     * Pauses playback. Call play() to resume.
     *
     * @throws IllegalStateException if the internal player engine has not been
     * initialized.
     */
    @Override
    public void pause() {
        stayAwake(false);
        _pause();
    }

    private native void _pause() throws IllegalStateException;

    //--------------------------------------------------------------------------
    // Explicit Routing
    //--------------------
    private AudioDeviceInfo mPreferredDevice = null;

    /**
     * Specifies an audio device (via an {@link AudioDeviceInfo} object) to route
     * the output from this MediaPlayer2.
     * @param deviceInfo The {@link AudioDeviceInfo} specifying the audio sink or source.
     *  If deviceInfo is null, default routing is restored.
     * @return true if succesful, false if the specified {@link AudioDeviceInfo} is non-null and
     * does not correspond to a valid audio device.
     */
    @Override
    public boolean setPreferredDevice(AudioDeviceInfo deviceInfo) {
        if (deviceInfo != null && !deviceInfo.isSink()) {
            return false;
        }
        int preferredDeviceId = deviceInfo != null ? deviceInfo.getId() : 0;
        boolean status = native_setOutputDevice(preferredDeviceId);
        if (status == true) {
            synchronized (this) {
                mPreferredDevice = deviceInfo;
            }
        }
        return status;
    }

    /**
     * Returns the selected output specified by {@link #setPreferredDevice}. Note that this
     * is not guaranteed to correspond to the actual device being used for playback.
     */
    @Override
    public AudioDeviceInfo getPreferredDevice() {
        synchronized (this) {
            return mPreferredDevice;
        }
    }

    /**
     * Returns an {@link AudioDeviceInfo} identifying the current routing of this MediaPlayer2
     * Note: The query is only valid if the MediaPlayer2 is currently playing.
     * If the player is not playing, the returned device can be null or correspond to previously
     * selected device when the player was last active.
     */
    @Override
    public AudioDeviceInfo getRoutedDevice() {
        int deviceId = native_getRoutedDeviceId();
        if (deviceId == 0) {
            return null;
        }
        AudioDeviceInfo[] devices =
                AudioManager.getDevicesStatic(AudioManager.GET_DEVICES_OUTPUTS);
        for (int i = 0; i < devices.length; i++) {
            if (devices[i].getId() == deviceId) {
                return devices[i];
            }
        }
        return null;
    }

    /*
     * Call BEFORE adding a routing callback handler or AFTER removing a routing callback handler.
     */
    @GuardedBy("mRoutingChangeListeners")
    private void enableNativeRoutingCallbacksLocked(boolean enabled) {
        if (mRoutingChangeListeners.size() == 0) {
            native_enableDeviceCallback(enabled);
        }
    }

    /**
     * The list of AudioRouting.OnRoutingChangedListener interfaces added (with
     * {@link #addOnRoutingChangedListener(android.media.AudioRouting.OnRoutingChangedListener, Handler)}
     * by an app to receive (re)routing notifications.
     */
    @GuardedBy("mRoutingChangeListeners")
    private ArrayMap<AudioRouting.OnRoutingChangedListener,
            NativeRoutingEventHandlerDelegate> mRoutingChangeListeners = new ArrayMap<>();

    /**
     * Adds an {@link AudioRouting.OnRoutingChangedListener} to receive notifications of routing
     * changes on this MediaPlayer2.
     * @param listener The {@link AudioRouting.OnRoutingChangedListener} interface to receive
     * notifications of rerouting events.
     * @param handler  Specifies the {@link Handler} object for the thread on which to execute
     * the callback. If <code>null</code>, the handler on the main looper will be used.
     */
    @Override
    public void addOnRoutingChangedListener(AudioRouting.OnRoutingChangedListener listener,
            Handler handler) {
        synchronized (mRoutingChangeListeners) {
            if (listener != null && !mRoutingChangeListeners.containsKey(listener)) {
                enableNativeRoutingCallbacksLocked(true);
                mRoutingChangeListeners.put(
                        listener, new NativeRoutingEventHandlerDelegate(this, listener,
                                handler != null ? handler : mEventHandler));
            }
        }
    }

    /**
     * Removes an {@link AudioRouting.OnRoutingChangedListener} which has been previously added
     * to receive rerouting notifications.
     * @param listener The previously added {@link AudioRouting.OnRoutingChangedListener} interface
     * to remove.
     */
    @Override
    public void removeOnRoutingChangedListener(AudioRouting.OnRoutingChangedListener listener) {
        synchronized (mRoutingChangeListeners) {
            if (mRoutingChangeListeners.containsKey(listener)) {
                mRoutingChangeListeners.remove(listener);
                enableNativeRoutingCallbacksLocked(false);
            }
        }
    }

    private native final boolean native_setOutputDevice(int deviceId);
    private native final int native_getRoutedDeviceId();
    private native final void native_enableDeviceCallback(boolean enabled);

    /**
     * Set the low-level power management behavior for this MediaPlayer2.  This
     * can be used when the MediaPlayer2 is not playing through a SurfaceHolder
     * set with {@link #setDisplay(SurfaceHolder)} and thus can use the
     * high-level {@link #setScreenOnWhilePlaying(boolean)} feature.
     *
     * <p>This function has the MediaPlayer2 access the low-level power manager
     * service to control the device's power usage while playing is occurring.
     * The parameter is a combination of {@link android.os.PowerManager} wake flags.
     * Use of this method requires {@link android.Manifest.permission#WAKE_LOCK}
     * permission.
     * By default, no attempt is made to keep the device awake during playback.
     *
     * @param context the Context to use
     * @param mode    the power/wake mode to set
     * @see android.os.PowerManager
     * @hide
     */
    @Override
    public void setWakeMode(Context context, int mode) {
        boolean washeld = false;

        /* Disable persistant wakelocks in media player based on property */
        if (SystemProperties.getBoolean("audio.offload.ignore_setawake", false) == true) {
            Log.w(TAG, "IGNORING setWakeMode " + mode);
            return;
        }

        if (mWakeLock != null) {
            if (mWakeLock.isHeld()) {
                washeld = true;
                mWakeLock.release();
            }
            mWakeLock = null;
        }

        PowerManager pm = (PowerManager)context.getSystemService(Context.POWER_SERVICE);
        mWakeLock = pm.newWakeLock(mode|PowerManager.ON_AFTER_RELEASE, MediaPlayer2Impl.class.getName());
        mWakeLock.setReferenceCounted(false);
        if (washeld) {
            mWakeLock.acquire();
        }
    }

    /**
     * Control whether we should use the attached SurfaceHolder to keep the
     * screen on while video playback is occurring.  This is the preferred
     * method over {@link #setWakeMode} where possible, since it doesn't
     * require that the application have permission for low-level wake lock
     * access.
     *
     * @param screenOn Supply true to keep the screen on, false to allow it
     * to turn off.
     * @hide
     */
    @Override
    public void setScreenOnWhilePlaying(boolean screenOn) {
        if (mScreenOnWhilePlaying != screenOn) {
            if (screenOn && mSurfaceHolder == null) {
                Log.w(TAG, "setScreenOnWhilePlaying(true) is ineffective without a SurfaceHolder");
            }
            mScreenOnWhilePlaying = screenOn;
            updateSurfaceScreenOn();
        }
    }

    private void stayAwake(boolean awake) {
        if (mWakeLock != null) {
            if (awake && !mWakeLock.isHeld()) {
                mWakeLock.acquire();
            } else if (!awake && mWakeLock.isHeld()) {
                mWakeLock.release();
            }
        }
        mStayAwake = awake;
        updateSurfaceScreenOn();
    }

    private void updateSurfaceScreenOn() {
        if (mSurfaceHolder != null) {
            mSurfaceHolder.setKeepScreenOn(mScreenOnWhilePlaying && mStayAwake);
        }
    }

    /**
     * Returns the width of the video.
     *
     * @return the width of the video, or 0 if there is no video,
     * no display surface was set, or the width has not been determined
     * yet. The {@code EventCallback} can be registered via
     * {@link #registerEventCallback(Executor, EventCallback)} to provide a
     * notification {@code EventCallback.onVideoSizeChanged} when the width is available.
     */
    @Override
    public native int getVideoWidth();

    /**
     * Returns the height of the video.
     *
     * @return the height of the video, or 0 if there is no video,
     * no display surface was set, or the height has not been determined
     * yet. The {@code EventCallback} can be registered via
     * {@link #registerEventCallback(Executor, EventCallback)} to provide a
     * notification {@code EventCallback.onVideoSizeChanged} when the height is available.
     */
    @Override
    public native int getVideoHeight();

    /**
     * Return Metrics data about the current player.
     *
     * @return a {@link PersistableBundle} containing the set of attributes and values
     * available for the media being handled by this instance of MediaPlayer2
     * The attributes are descibed in {@link MetricsConstants}.
     *
     *  Additional vendor-specific fields may also be present in
     *  the return value.
     */
    @Override
    public PersistableBundle getMetrics() {
        PersistableBundle bundle = native_getMetrics();
        return bundle;
    }

    private native PersistableBundle native_getMetrics();

    /**
     * Checks whether the MediaPlayer2 is playing.
     *
     * @return true if currently playing, false otherwise
     * @throws IllegalStateException if the internal player engine has not been
     * initialized or has been released.
     */
    @Override
    public native boolean isPlaying();

    /**
     * Gets the current buffering management params used by the source component.
     * Calling it only after {@code setDataSource} has been called.
     * Each type of data source might have different set of default params.
     *
     * @return the current buffering management params used by the source component.
     * @throws IllegalStateException if the internal player engine has not been
     * initialized, or {@code setDataSource} has not been called.
     * @hide
     */
    @Override
    @NonNull
    public native BufferingParams getBufferingParams();

    /**
     * Sets buffering management params.
     * The object sets its internal BufferingParams to the input, except that the input is
     * invalid or not supported.
     * Call it only after {@code setDataSource} has been called.
     * The input is a hint to MediaPlayer2.
     *
     * @param params the buffering management params.
     *
     * @throws IllegalStateException if the internal player engine has not been
     * initialized or has been released, or {@code setDataSource} has not been called.
     * @throws IllegalArgumentException if params is invalid or not supported.
     * @hide
     */
    @Override
    public native void setBufferingParams(@NonNull BufferingParams params);

    /**
     * Sets playback rate and audio mode.
     *
     * @param rate the ratio between desired playback rate and normal one.
     * @param audioMode audio playback mode. Must be one of the supported
     * audio modes.
     *
     * @throws IllegalStateException if the internal player engine has not been
     * initialized.
     * @throws IllegalArgumentException if audioMode is not supported.
     *
     * @hide
     */
    @Override
    @NonNull
    public PlaybackParams easyPlaybackParams(float rate, @PlaybackRateAudioMode int audioMode) {
        PlaybackParams params = new PlaybackParams();
        params.allowDefaults();
        switch (audioMode) {
        case PLAYBACK_RATE_AUDIO_MODE_DEFAULT:
            params.setSpeed(rate).setPitch(1.0f);
            break;
        case PLAYBACK_RATE_AUDIO_MODE_STRETCH:
            params.setSpeed(rate).setPitch(1.0f)
                    .setAudioFallbackMode(params.AUDIO_FALLBACK_MODE_FAIL);
            break;
        case PLAYBACK_RATE_AUDIO_MODE_RESAMPLE:
            params.setSpeed(rate).setPitch(rate);
            break;
        default:
            final String msg = "Audio playback mode " + audioMode + " is not supported";
            throw new IllegalArgumentException(msg);
        }
        return params;
    }

    /**
     * Sets playback rate using {@link PlaybackParams}. The object sets its internal
     * PlaybackParams to the input, except that the object remembers previous speed
     * when input speed is zero. This allows the object to resume at previous speed
     * when play() is called. Calling it before the object is prepared does not change
     * the object state. After the object is prepared, calling it with zero speed is
     * equivalent to calling pause(). After the object is prepared, calling it with
     * non-zero speed is equivalent to calling play().
     *
     * @param params the playback params.
     *
     * @throws IllegalStateException if the internal player engine has not been
     * initialized or has been released.
     * @throws IllegalArgumentException if params is not supported.
     */
    @Override
    public native void setPlaybackParams(@NonNull PlaybackParams params);

    /**
     * Gets the playback params, containing the current playback rate.
     *
     * @return the playback params.
     * @throws IllegalStateException if the internal player engine has not been
     * initialized.
     */
    @Override
    @NonNull
    public native PlaybackParams getPlaybackParams();

    /**
     * Sets A/V sync mode.
     *
     * @param params the A/V sync params to apply
     *
     * @throws IllegalStateException if the internal player engine has not been
     * initialized.
     * @throws IllegalArgumentException if params are not supported.
     */
    @Override
    public native void setSyncParams(@NonNull SyncParams params);

    /**
     * Gets the A/V sync mode.
     *
     * @return the A/V sync params
     *
     * @throws IllegalStateException if the internal player engine has not been
     * initialized.
     */
    @Override
    @NonNull
    public native SyncParams getSyncParams();

    private native final void _seekTo(long msec, int mode);

    /**
     * Moves the media to specified time position by considering the given mode.
     * <p>
     * When seekTo is finished, the user will be notified via OnSeekComplete supplied by the user.
     * There is at most one active seekTo processed at any time. If there is a to-be-completed
     * seekTo, new seekTo requests will be queued in such a way that only the last request
     * is kept. When current seekTo is completed, the queued request will be processed if
     * that request is different from just-finished seekTo operation, i.e., the requested
     * position or mode is different.
     *
     * @param msec the offset in milliseconds from the start to seek to.
     * When seeking to the given time position, there is no guarantee that the data source
     * has a frame located at the position. When this happens, a frame nearby will be rendered.
     * If msec is negative, time position zero will be used.
     * If msec is larger than duration, duration will be used.
     * @param mode the mode indicating where exactly to seek to.
     * Use {@link #SEEK_PREVIOUS_SYNC} if one wants to seek to a sync frame
     * that has a timestamp earlier than or the same as msec. Use
     * {@link #SEEK_NEXT_SYNC} if one wants to seek to a sync frame
     * that has a timestamp later than or the same as msec. Use
     * {@link #SEEK_CLOSEST_SYNC} if one wants to seek to a sync frame
     * that has a timestamp closest to or the same as msec. Use
     * {@link #SEEK_CLOSEST} if one wants to seek to a frame that may
     * or may not be a sync frame but is closest to or the same as msec.
     * {@link #SEEK_CLOSEST} often has larger performance overhead compared
     * to the other options if there is no sync frame located at msec.
     * @throws IllegalStateException if the internal player engine has not been
     * initialized
     * @throws IllegalArgumentException if the mode is invalid.
     */
    @Override
    public void seekTo(long msec, @SeekMode int mode) {
        if (mode < SEEK_PREVIOUS_SYNC || mode > SEEK_CLOSEST) {
            final String msg = "Illegal seek mode: " + mode;
            throw new IllegalArgumentException(msg);
        }
        // TODO: pass long to native, instead of truncating here.
        if (msec > Integer.MAX_VALUE) {
            Log.w(TAG, "seekTo offset " + msec + " is too large, cap to " + Integer.MAX_VALUE);
            msec = Integer.MAX_VALUE;
        } else if (msec < Integer.MIN_VALUE) {
            Log.w(TAG, "seekTo offset " + msec + " is too small, cap to " + Integer.MIN_VALUE);
            msec = Integer.MIN_VALUE;
        }
        _seekTo(msec, mode);
    }

    /**
     * Get current playback position as a {@link MediaTimestamp}.
     * <p>
     * The MediaTimestamp represents how the media time correlates to the system time in
     * a linear fashion using an anchor and a clock rate. During regular playback, the media
     * time moves fairly constantly (though the anchor frame may be rebased to a current
     * system time, the linear correlation stays steady). Therefore, this method does not
     * need to be called often.
     * <p>
     * To help users get current playback position, this method always anchors the timestamp
     * to the current {@link System#nanoTime system time}, so
     * {@link MediaTimestamp#getAnchorMediaTimeUs} can be used as current playback position.
     *
     * @return a MediaTimestamp object if a timestamp is available, or {@code null} if no timestamp
     *         is available, e.g. because the media player has not been initialized.
     *
     * @see MediaTimestamp
     */
    @Override
    @Nullable
    public MediaTimestamp getTimestamp()
    {
        try {
            // TODO: get the timestamp from native side
            return new MediaTimestamp(
                    getCurrentPosition() * 1000L,
                    System.nanoTime(),
                    isPlaying() ? getPlaybackParams().getSpeed() : 0.f);
        } catch (IllegalStateException e) {
            return null;
        }
    }

    /**
     * Gets the current playback position.
     *
     * @return the current position in milliseconds
     */
    @Override
    public native int getCurrentPosition();

    /**
     * Gets the duration of the file.
     *
     * @return the duration in milliseconds, if no duration is available
     *         (for example, if streaming live content), -1 is returned.
     */
    @Override
    public native int getDuration();

    /**
     * Gets the media metadata.
     *
     * @param update_only controls whether the full set of available
     * metadata is returned or just the set that changed since the
     * last call. See {@see #METADATA_UPDATE_ONLY} and {@see
     * #METADATA_ALL}.
     *
     * @param apply_filter if true only metadata that matches the
     * filter is returned. See {@see #APPLY_METADATA_FILTER} and {@see
     * #BYPASS_METADATA_FILTER}.
     *
     * @return The metadata, possibly empty. null if an error occured.
     // FIXME: unhide.
     * {@hide}
     */
    @Override
    public Metadata getMetadata(final boolean update_only,
                                final boolean apply_filter) {
        Parcel reply = Parcel.obtain();
        Metadata data = new Metadata();

        if (!native_getMetadata(update_only, apply_filter, reply)) {
            reply.recycle();
            return null;
        }

        // Metadata takes over the parcel, don't recycle it unless
        // there is an error.
        if (!data.parse(reply)) {
            reply.recycle();
            return null;
        }
        return data;
    }

    /**
     * Set a filter for the metadata update notification and update
     * retrieval. The caller provides 2 set of metadata keys, allowed
     * and blocked. The blocked set always takes precedence over the
     * allowed one.
     * Metadata.MATCH_ALL and Metadata.MATCH_NONE are 2 sets available as
     * shorthands to allow/block all or no metadata.
     *
     * By default, there is no filter set.
     *
     * @param allow Is the set of metadata the client is interested
     *              in receiving new notifications for.
     * @param block Is the set of metadata the client is not interested
     *              in receiving new notifications for.
     * @return The call status code.
     *
     // FIXME: unhide.
     * {@hide}
     */
    @Override
    public int setMetadataFilter(Set<Integer> allow, Set<Integer> block) {
        // Do our serialization manually instead of calling
        // Parcel.writeArray since the sets are made of the same type
        // we avoid paying the price of calling writeValue (used by
        // writeArray) which burns an extra int per element to encode
        // the type.
        Parcel request =  newRequest();

        // The parcel starts already with an interface token. There
        // are 2 filters. Each one starts with a 4bytes number to
        // store the len followed by a number of int (4 bytes as well)
        // representing the metadata type.
        int capacity = request.dataSize() + 4 * (1 + allow.size() + 1 + block.size());

        if (request.dataCapacity() < capacity) {
            request.setDataCapacity(capacity);
        }

        request.writeInt(allow.size());
        for(Integer t: allow) {
            request.writeInt(t);
        }
        request.writeInt(block.size());
        for(Integer t: block) {
            request.writeInt(t);
        }
        return native_setMetadataFilter(request);
    }

    /**
     * Set the MediaPlayer2 to start when this MediaPlayer2 finishes playback
     * (i.e. reaches the end of the stream).
     * The media framework will attempt to transition from this player to
     * the next as seamlessly as possible. The next player can be set at
     * any time before completion, but shall be after setDataSource has been
     * called successfully. The next player must be prepared by the
     * app, and the application should not call play() on it.
     * The next MediaPlayer2 must be different from 'this'. An exception
     * will be thrown if next == this.
     * The application may call setNextMediaPlayer(null) to indicate no
     * next player should be started at the end of playback.
     * If the current player is looping, it will keep looping and the next
     * player will not be started.
     *
     * @param next the player to start after this one completes playback.
     *
     * @hide
     */
    @Override
    public native void setNextMediaPlayer(MediaPlayer2 next);

    /**
     * Resets the MediaPlayer2 to its uninitialized state. After calling
     * this method, you will have to initialize it again by setting the
     * data source and calling prepare().
     */
    @Override
    public void reset() {
        mSelectedSubtitleTrackIndex = -1;
        synchronized(mOpenSubtitleSources) {
            for (final InputStream is: mOpenSubtitleSources) {
                try {
                    is.close();
                } catch (IOException e) {
                }
            }
            mOpenSubtitleSources.clear();
        }
        if (mSubtitleController != null) {
            mSubtitleController.reset();
        }
        if (mTimeProvider != null) {
            mTimeProvider.close();
            mTimeProvider = null;
        }

        synchronized (mEventCbLock) {
            mEventCallbackRecords.clear();
        }
        synchronized (mDrmEventCbLock) {
            mDrmEventCallbackRecords.clear();
        }

        stayAwake(false);
        _reset();
        // make sure none of the listeners get called anymore
        if (mEventHandler != null) {
            mEventHandler.removeCallbacksAndMessages(null);
        }

        synchronized (mIndexTrackPairs) {
            mIndexTrackPairs.clear();
            mInbandTrackIndices.clear();
        };

        resetDrmState();
    }

    private native void _reset();

    /**
     * Set up a timer for {@link #TimeProvider}. {@link #TimeProvider} will be
     * notified when the presentation time reaches (becomes greater than or equal to)
     * the value specified.
     *
     * @param mediaTimeUs presentation time to get timed event callback at
     * @hide
     */
    @Override
    public void notifyAt(long mediaTimeUs) {
        _notifyAt(mediaTimeUs);
    }

    private native void _notifyAt(long mediaTimeUs);

    // Keep KEY_PARAMETER_* in sync with include/media/mediaplayer2.h
    private final static int KEY_PARAMETER_AUDIO_ATTRIBUTES = 1400;
    /**
     * Sets the parameter indicated by key.
     * @param key key indicates the parameter to be set.
     * @param value value of the parameter to be set.
     * @return true if the parameter is set successfully, false otherwise
     * {@hide}
     */
    private native boolean setParameter(int key, Parcel value);

    /**
     * Sets the audio attributes for this MediaPlayer2.
     * See {@link AudioAttributes} for how to build and configure an instance of this class.
     * You must call this method before {@link #prepare()} or {@link #prepareAsync()} in order
     * for the audio attributes to become effective thereafter.
     * @param attributes a non-null set of audio attributes
     * @throws IllegalArgumentException if the attributes are null or invalid.
     */
    @Override
    public void setAudioAttributes(AudioAttributes attributes) {
        if (attributes == null) {
            final String msg = "Cannot set AudioAttributes to null";
            throw new IllegalArgumentException(msg);
        }
        mUsage = attributes.getUsage();
        mBypassInterruptionPolicy = (attributes.getAllFlags()
                & AudioAttributes.FLAG_BYPASS_INTERRUPTION_POLICY) != 0;
        Parcel pattributes = Parcel.obtain();
        attributes.writeToParcel(pattributes, AudioAttributes.FLATTEN_TAGS);
        setParameter(KEY_PARAMETER_AUDIO_ATTRIBUTES, pattributes);
        pattributes.recycle();
    }

    /**
     * Sets the player to be looping or non-looping.
     *
     * @param looping whether to loop or not
     * @hide
     */
    @Override
    public native void setLooping(boolean looping);

    /**
     * Checks whether the MediaPlayer2 is looping or non-looping.
     *
     * @return true if the MediaPlayer2 is currently looping, false otherwise
     * @hide
     */
    @Override
    public native boolean isLooping();

    /**
     * Sets the volume on this player.
     * This API is recommended for balancing the output of audio streams
     * within an application. Unless you are writing an application to
     * control user settings, this API should be used in preference to
     * {@link AudioManager#setStreamVolume(int, int, int)} which sets the volume of ALL streams of
     * a particular type. Note that the passed volume values are raw scalars in range 0.0 to 1.0.
     * UI controls should be scaled logarithmically.
     *
     * @param leftVolume left volume scalar
     * @param rightVolume right volume scalar
     */
    /*
     * FIXME: Merge this into javadoc comment above when setVolume(float) is not @hide.
     * The single parameter form below is preferred if the channel volumes don't need
     * to be set independently.
     */
    @Override
    public void setVolume(float leftVolume, float rightVolume) {
        _setVolume(leftVolume, rightVolume);
    }

    private native void _setVolume(float leftVolume, float rightVolume);

    /**
     * Similar, excepts sets volume of all channels to same value.
     * @hide
     */
    @Override
    public void setVolume(float volume) {
        setVolume(volume, volume);
    }

    /**
     * Sets the audio session ID.
     *
     * @param sessionId the audio session ID.
     * The audio session ID is a system wide unique identifier for the audio stream played by
     * this MediaPlayer2 instance.
     * The primary use of the audio session ID  is to associate audio effects to a particular
     * instance of MediaPlayer2: if an audio session ID is provided when creating an audio effect,
     * this effect will be applied only to the audio content of media players within the same
     * audio session and not to the output mix.
     * When created, a MediaPlayer2 instance automatically generates its own audio session ID.
     * However, it is possible to force this player to be part of an already existing audio session
     * by calling this method.
     * This method must be called before one of the overloaded <code> setDataSource </code> methods.
     * @throws IllegalStateException if it is called in an invalid state
     * @throws IllegalArgumentException if the sessionId is invalid.
     */
    @Override
    public native void setAudioSessionId(int sessionId);

    /**
     * Returns the audio session ID.
     *
     * @return the audio session ID. {@see #setAudioSessionId(int)}
     * Note that the audio session ID is 0 only if a problem occured when the MediaPlayer2 was contructed.
     */
    @Override
    public native int getAudioSessionId();

    /**
     * Attaches an auxiliary effect to the player. A typical auxiliary effect is a reverberation
     * effect which can be applied on any sound source that directs a certain amount of its
     * energy to this effect. This amount is defined by setAuxEffectSendLevel().
     * See {@link #setAuxEffectSendLevel(float)}.
     * <p>After creating an auxiliary effect (e.g.
     * {@link android.media.audiofx.EnvironmentalReverb}), retrieve its ID with
     * {@link android.media.audiofx.AudioEffect#getId()} and use it when calling this method
     * to attach the player to the effect.
     * <p>To detach the effect from the player, call this method with a null effect id.
     * <p>This method must be called after one of the overloaded <code> setDataSource </code>
     * methods.
     * @param effectId system wide unique id of the effect to attach
     */
    @Override
    public native void attachAuxEffect(int effectId);


    /**
     * Sets the send level of the player to the attached auxiliary effect.
     * See {@link #attachAuxEffect(int)}. The level value range is 0 to 1.0.
     * <p>By default the send level is 0, so even if an effect is attached to the player
     * this method must be called for the effect to be applied.
     * <p>Note that the passed level value is a raw scalar. UI controls should be scaled
     * logarithmically: the gain applied by audio framework ranges from -72dB to 0dB,
     * so an appropriate conversion from linear UI input x to level is:
     * x == 0 -> level = 0
     * 0 < x <= R -> level = 10^(72*(x-R)/20/R)
     * @param level send level scalar
     */
    @Override
    public void setAuxEffectSendLevel(float level) {
        _setAuxEffectSendLevel(level);
    }

    private native void _setAuxEffectSendLevel(float level);

    /*
     * @param request Parcel destinated to the media player.
     * @param reply[out] Parcel that will contain the reply.
     * @return The status code.
     */
    private native final int native_invoke(Parcel request, Parcel reply);


    /*
     * @param update_only If true fetch only the set of metadata that have
     *                    changed since the last invocation of getMetadata.
     *                    The set is built using the unfiltered
     *                    notifications the native player sent to the
     *                    MediaPlayer2Manager during that period of
     *                    time. If false, all the metadatas are considered.
     * @param apply_filter  If true, once the metadata set has been built based on
     *                     the value update_only, the current filter is applied.
     * @param reply[out] On return contains the serialized
     *                   metadata. Valid only if the call was successful.
     * @return The status code.
     */
    private native final boolean native_getMetadata(boolean update_only,
                                                    boolean apply_filter,
                                                    Parcel reply);

    /*
     * @param request Parcel with the 2 serialized lists of allowed
     *                metadata types followed by the one to be
     *                dropped. Each list starts with an integer
     *                indicating the number of metadata type elements.
     * @return The status code.
     */
    private native final int native_setMetadataFilter(Parcel request);

    private static native final void native_init();
    private native final void native_setup(Object mediaplayer2_this);
    private native final void native_finalize();

    private static native final void native_stream_event_onTearDown(
            long nativeCallbackPtr, long userDataPtr);
    private static native final void native_stream_event_onStreamPresentationEnd(
            long nativeCallbackPtr, long userDataPtr);
    private static native final void native_stream_event_onStreamDataRequest(
            long jAudioTrackPtr, long nativeCallbackPtr, long userDataPtr);

    /**
     * Class for MediaPlayer2 to return each audio/video/subtitle track's metadata.
     *
     * @see android.media.MediaPlayer2#getTrackInfo
     */
    public static final class TrackInfoImpl extends TrackInfo {
        /**
         * Gets the track type.
         * @return TrackType which indicates if the track is video, audio, timed text.
         */
        @Override
        public int getTrackType() {
            return mTrackType;
        }

        /**
         * Gets the language code of the track.
         * @return a language code in either way of ISO-639-1 or ISO-639-2.
         * When the language is unknown or could not be determined,
         * ISO-639-2 language code, "und", is returned.
         */
        @Override
        public String getLanguage() {
            String language = mFormat.getString(MediaFormat.KEY_LANGUAGE);
            return language == null ? "und" : language;
        }

        /**
         * Gets the {@link MediaFormat} of the track.  If the format is
         * unknown or could not be determined, null is returned.
         */
        @Override
        public MediaFormat getFormat() {
            if (mTrackType == MEDIA_TRACK_TYPE_TIMEDTEXT
                    || mTrackType == MEDIA_TRACK_TYPE_SUBTITLE) {
                return mFormat;
            }
            return null;
        }

        final int mTrackType;
        final MediaFormat mFormat;

        TrackInfoImpl(Parcel in) {
            mTrackType = in.readInt();
            // TODO: parcel in the full MediaFormat; currently we are using createSubtitleFormat
            // even for audio/video tracks, meaning we only set the mime and language.
            String mime = in.readString();
            String language = in.readString();
            mFormat = MediaFormat.createSubtitleFormat(mime, language);

            if (mTrackType == MEDIA_TRACK_TYPE_SUBTITLE) {
                mFormat.setInteger(MediaFormat.KEY_IS_AUTOSELECT, in.readInt());
                mFormat.setInteger(MediaFormat.KEY_IS_DEFAULT, in.readInt());
                mFormat.setInteger(MediaFormat.KEY_IS_FORCED_SUBTITLE, in.readInt());
            }
        }

        /** @hide */
        TrackInfoImpl(int type, MediaFormat format) {
            mTrackType = type;
            mFormat = format;
        }

        /**
         * Flatten this object in to a Parcel.
         *
         * @param dest The Parcel in which the object should be written.
         * @param flags Additional flags about how the object should be written.
         * May be 0 or {@link android.os.Parcelable#PARCELABLE_WRITE_RETURN_VALUE}.
         */
        /* package private */ void writeToParcel(Parcel dest, int flags) {
            dest.writeInt(mTrackType);
            dest.writeString(getLanguage());

            if (mTrackType == MEDIA_TRACK_TYPE_SUBTITLE) {
                dest.writeString(mFormat.getString(MediaFormat.KEY_MIME));
                dest.writeInt(mFormat.getInteger(MediaFormat.KEY_IS_AUTOSELECT));
                dest.writeInt(mFormat.getInteger(MediaFormat.KEY_IS_DEFAULT));
                dest.writeInt(mFormat.getInteger(MediaFormat.KEY_IS_FORCED_SUBTITLE));
            }
        }

        @Override
        public String toString() {
            StringBuilder out = new StringBuilder(128);
            out.append(getClass().getName());
            out.append('{');
            switch (mTrackType) {
            case MEDIA_TRACK_TYPE_VIDEO:
                out.append("VIDEO");
                break;
            case MEDIA_TRACK_TYPE_AUDIO:
                out.append("AUDIO");
                break;
            case MEDIA_TRACK_TYPE_TIMEDTEXT:
                out.append("TIMEDTEXT");
                break;
            case MEDIA_TRACK_TYPE_SUBTITLE:
                out.append("SUBTITLE");
                break;
            default:
                out.append("UNKNOWN");
                break;
            }
            out.append(", " + mFormat.toString());
            out.append("}");
            return out.toString();
        }

        /**
         * Used to read a TrackInfoImpl from a Parcel.
         */
        /* package private */ static final Parcelable.Creator<TrackInfoImpl> CREATOR
                = new Parcelable.Creator<TrackInfoImpl>() {
                    @Override
                    public TrackInfoImpl createFromParcel(Parcel in) {
                        return new TrackInfoImpl(in);
                    }

                    @Override
                    public TrackInfoImpl[] newArray(int size) {
                        return new TrackInfoImpl[size];
                    }
                };

    };

    // We would like domain specific classes with more informative names than the `first` and `second`
    // in generic Pair, but we would also like to avoid creating new/trivial classes. As a compromise
    // we document the meanings of `first` and `second` here:
    //
    // Pair.first - inband track index; non-null iff representing an inband track.
    // Pair.second - a SubtitleTrack registered with mSubtitleController; non-null iff representing
    //               an inband subtitle track or any out-of-band track (subtitle or timedtext).
    private Vector<Pair<Integer, SubtitleTrack>> mIndexTrackPairs = new Vector<>();
    private BitSet mInbandTrackIndices = new BitSet();

    /**
     * Returns a List of track information.
     *
     * @return List of track info. The total number of tracks is the array length.
     * Must be called again if an external timed text source has been added after
     * addTimedTextSource method is called.
     * @throws IllegalStateException if it is called in an invalid state.
     */
    @Override
    public List<TrackInfo> getTrackInfo() {
        TrackInfoImpl trackInfo[] = getInbandTrackInfoImpl();
        // add out-of-band tracks
        synchronized (mIndexTrackPairs) {
            TrackInfoImpl allTrackInfo[] = new TrackInfoImpl[mIndexTrackPairs.size()];
            for (int i = 0; i < allTrackInfo.length; i++) {
                Pair<Integer, SubtitleTrack> p = mIndexTrackPairs.get(i);
                if (p.first != null) {
                    // inband track
                    allTrackInfo[i] = trackInfo[p.first];
                } else {
                    SubtitleTrack track = p.second;
                    allTrackInfo[i] = new TrackInfoImpl(track.getTrackType(), track.getFormat());
                }
            }
            return Arrays.asList(allTrackInfo);
        }
    }

    private TrackInfoImpl[] getInbandTrackInfoImpl() throws IllegalStateException {
        Parcel request = Parcel.obtain();
        Parcel reply = Parcel.obtain();
        try {
            request.writeInt(INVOKE_ID_GET_TRACK_INFO);
            invoke(request, reply);
            TrackInfoImpl trackInfo[] = reply.createTypedArray(TrackInfoImpl.CREATOR);
            return trackInfo;
        } finally {
            request.recycle();
            reply.recycle();
        }
    }

    /*
     * A helper function to check if the mime type is supported by media framework.
     */
    private static boolean availableMimeTypeForExternalSource(String mimeType) {
        if (MEDIA_MIMETYPE_TEXT_SUBRIP.equals(mimeType)) {
            return true;
        }
        return false;
    }

    private SubtitleController mSubtitleController;

    /** @hide */
    @Override
    public void setSubtitleAnchor(
            SubtitleController controller,
            SubtitleController.Anchor anchor) {
        // TODO: create SubtitleController in MediaPlayer2
        mSubtitleController = controller;
        mSubtitleController.setAnchor(anchor);
    }

    /**
     * The private version of setSubtitleAnchor is used internally to set mSubtitleController if
     * necessary when clients don't provide their own SubtitleControllers using the public version
     * {@link #setSubtitleAnchor(SubtitleController, Anchor)} (e.g. {@link VideoView} provides one).
     */
    private synchronized void setSubtitleAnchor() {
        if ((mSubtitleController == null) && (ActivityThread.currentApplication() != null)) {
            final HandlerThread thread = new HandlerThread("SetSubtitleAnchorThread");
            thread.start();
            Handler handler = new Handler(thread.getLooper());
            handler.post(new Runnable() {
                @Override
                public void run() {
                    Context context = ActivityThread.currentApplication();
                    mSubtitleController = new SubtitleController(context, mTimeProvider, MediaPlayer2Impl.this);
                    mSubtitleController.setAnchor(new Anchor() {
                        @Override
                        public void setSubtitleWidget(RenderingWidget subtitleWidget) {
                        }

                        @Override
                        public Looper getSubtitleLooper() {
                            return Looper.getMainLooper();
                        }
                    });
                    thread.getLooper().quitSafely();
                }
            });
            try {
                thread.join();
            } catch (InterruptedException e) {
                Thread.currentThread().interrupt();
                Log.w(TAG, "failed to join SetSubtitleAnchorThread");
            }
        }
    }

    private int mSelectedSubtitleTrackIndex = -1;
    private Vector<InputStream> mOpenSubtitleSources;

    private OnSubtitleDataListener mSubtitleDataListener = new OnSubtitleDataListener() {
        @Override
        public void onSubtitleData(MediaPlayer2 mp, SubtitleData data) {
            int index = data.getTrackIndex();
            synchronized (mIndexTrackPairs) {
                for (Pair<Integer, SubtitleTrack> p : mIndexTrackPairs) {
                    if (p.first != null && p.first == index && p.second != null) {
                        // inband subtitle track that owns data
                        SubtitleTrack track = p.second;
                        track.onData(data);
                    }
                }
            }
        }
    };

    /** @hide */
    @Override
    public void onSubtitleTrackSelected(SubtitleTrack track) {
        if (mSelectedSubtitleTrackIndex >= 0) {
            try {
                selectOrDeselectInbandTrack(mSelectedSubtitleTrackIndex, false);
            } catch (IllegalStateException e) {
            }
            mSelectedSubtitleTrackIndex = -1;
        }
        setOnSubtitleDataListener(null);
        if (track == null) {
            return;
        }

        synchronized (mIndexTrackPairs) {
            for (Pair<Integer, SubtitleTrack> p : mIndexTrackPairs) {
                if (p.first != null && p.second == track) {
                    // inband subtitle track that is selected
                    mSelectedSubtitleTrackIndex = p.first;
                    break;
                }
            }
        }

        if (mSelectedSubtitleTrackIndex >= 0) {
            try {
                selectOrDeselectInbandTrack(mSelectedSubtitleTrackIndex, true);
            } catch (IllegalStateException e) {
            }
            setOnSubtitleDataListener(mSubtitleDataListener);
        }
        // no need to select out-of-band tracks
    }

    /** @hide */
    @Override
    public void addSubtitleSource(InputStream is, MediaFormat format)
            throws IllegalStateException
    {
        final InputStream fIs = is;
        final MediaFormat fFormat = format;

        if (is != null) {
            // Ensure all input streams are closed.  It is also a handy
            // way to implement timeouts in the future.
            synchronized(mOpenSubtitleSources) {
                mOpenSubtitleSources.add(is);
            }
        } else {
            Log.w(TAG, "addSubtitleSource called with null InputStream");
        }

        getMediaTimeProvider();

        // process each subtitle in its own thread
        final HandlerThread thread = new HandlerThread("SubtitleReadThread",
              Process.THREAD_PRIORITY_BACKGROUND + Process.THREAD_PRIORITY_MORE_FAVORABLE);
        thread.start();
        Handler handler = new Handler(thread.getLooper());
        handler.post(new Runnable() {
            private int addTrack() {
                if (fIs == null || mSubtitleController == null) {
                    return MEDIA_INFO_UNSUPPORTED_SUBTITLE;
                }

                SubtitleTrack track = mSubtitleController.addTrack(fFormat);
                if (track == null) {
                    return MEDIA_INFO_UNSUPPORTED_SUBTITLE;
                }

                // TODO: do the conversion in the subtitle track
                Scanner scanner = new Scanner(fIs, "UTF-8");
                String contents = scanner.useDelimiter("\\A").next();
                synchronized(mOpenSubtitleSources) {
                    mOpenSubtitleSources.remove(fIs);
                }
                scanner.close();
                synchronized (mIndexTrackPairs) {
                    mIndexTrackPairs.add(Pair.<Integer, SubtitleTrack>create(null, track));
                }
                Handler h = mTimeProvider.mEventHandler;
                int what = TimeProvider.NOTIFY;
                int arg1 = TimeProvider.NOTIFY_TRACK_DATA;
                Pair<SubtitleTrack, byte[]> trackData = Pair.create(track, contents.getBytes());
                Message m = h.obtainMessage(what, arg1, 0, trackData);
                h.sendMessage(m);
                return MEDIA_INFO_EXTERNAL_METADATA_UPDATE;
            }

            public void run() {
                int res = addTrack();
                if (mEventHandler != null) {
                    Message m = mEventHandler.obtainMessage(MEDIA_INFO, res, 0, null);
                    mEventHandler.sendMessage(m);
                }
                thread.getLooper().quitSafely();
            }
        });
    }

    private void scanInternalSubtitleTracks() {
        setSubtitleAnchor();

        populateInbandTracks();

        if (mSubtitleController != null) {
            mSubtitleController.selectDefaultTrack();
        }
    }

    private void populateInbandTracks() {
        TrackInfoImpl[] tracks = getInbandTrackInfoImpl();
        synchronized (mIndexTrackPairs) {
            for (int i = 0; i < tracks.length; i++) {
                if (mInbandTrackIndices.get(i)) {
                    continue;
                } else {
                    mInbandTrackIndices.set(i);
                }

                // newly appeared inband track
                if (tracks[i].getTrackType() == TrackInfo.MEDIA_TRACK_TYPE_SUBTITLE) {
                    SubtitleTrack track = mSubtitleController.addTrack(
                            tracks[i].getFormat());
                    mIndexTrackPairs.add(Pair.create(i, track));
                } else {
                    mIndexTrackPairs.add(Pair.<Integer, SubtitleTrack>create(i, null));
                }
            }
        }
    }

    /* TODO: Limit the total number of external timed text source to a reasonable number.
     */
    /**
     * Adds an external timed text source file.
     *
     * Currently supported format is SubRip with the file extension .srt, case insensitive.
     * Note that a single external timed text source may contain multiple tracks in it.
     * One can find the total number of available tracks using {@link #getTrackInfo()} to see what
     * additional tracks become available after this method call.
     *
     * @param path The file path of external timed text source file.
     * @param mimeType The mime type of the file. Must be one of the mime types listed above.
     * @throws IOException if the file cannot be accessed or is corrupted.
     * @throws IllegalArgumentException if the mimeType is not supported.
     * @throws IllegalStateException if called in an invalid state.
     * @hide
     */
    @Override
    public void addTimedTextSource(String path, String mimeType)
            throws IOException {
        if (!availableMimeTypeForExternalSource(mimeType)) {
            final String msg = "Illegal mimeType for timed text source: " + mimeType;
            throw new IllegalArgumentException(msg);
        }

        File file = new File(path);
        if (file.exists()) {
            FileInputStream is = new FileInputStream(file);
            FileDescriptor fd = is.getFD();
            addTimedTextSource(fd, mimeType);
            is.close();
        } else {
            // We do not support the case where the path is not a file.
            throw new IOException(path);
        }
    }


    /**
     * Adds an external timed text source file (Uri).
     *
     * Currently supported format is SubRip with the file extension .srt, case insensitive.
     * Note that a single external timed text source may contain multiple tracks in it.
     * One can find the total number of available tracks using {@link #getTrackInfo()} to see what
     * additional tracks become available after this method call.
     *
     * @param context the Context to use when resolving the Uri
     * @param uri the Content URI of the data you want to play
     * @param mimeType The mime type of the file. Must be one of the mime types listed above.
     * @throws IOException if the file cannot be accessed or is corrupted.
     * @throws IllegalArgumentException if the mimeType is not supported.
     * @throws IllegalStateException if called in an invalid state.
     * @hide
     */
    @Override
    public void addTimedTextSource(Context context, Uri uri, String mimeType)
            throws IOException {
        String scheme = uri.getScheme();
        if(scheme == null || scheme.equals("file")) {
            addTimedTextSource(uri.getPath(), mimeType);
            return;
        }

        AssetFileDescriptor fd = null;
        try {
            ContentResolver resolver = context.getContentResolver();
            fd = resolver.openAssetFileDescriptor(uri, "r");
            if (fd == null) {
                return;
            }
            addTimedTextSource(fd.getFileDescriptor(), mimeType);
            return;
        } catch (SecurityException ex) {
        } catch (IOException ex) {
        } finally {
            if (fd != null) {
                fd.close();
            }
        }
    }

    /**
     * Adds an external timed text source file (FileDescriptor).
     *
     * It is the caller's responsibility to close the file descriptor.
     * It is safe to do so as soon as this call returns.
     *
     * Currently supported format is SubRip. Note that a single external timed text source may
     * contain multiple tracks in it. One can find the total number of available tracks
     * using {@link #getTrackInfo()} to see what additional tracks become available
     * after this method call.
     *
     * @param fd the FileDescriptor for the file you want to play
     * @param mimeType The mime type of the file. Must be one of the mime types listed above.
     * @throws IllegalArgumentException if the mimeType is not supported.
     * @throws IllegalStateException if called in an invalid state.
     * @hide
     */
    @Override
    public void addTimedTextSource(FileDescriptor fd, String mimeType) {
        // intentionally less than LONG_MAX
        addTimedTextSource(fd, 0, 0x7ffffffffffffffL, mimeType);
    }

    /**
     * Adds an external timed text file (FileDescriptor).
     *
     * It is the caller's responsibility to close the file descriptor.
     * It is safe to do so as soon as this call returns.
     *
     * Currently supported format is SubRip. Note that a single external timed text source may
     * contain multiple tracks in it. One can find the total number of available tracks
     * using {@link #getTrackInfo()} to see what additional tracks become available
     * after this method call.
     *
     * @param fd the FileDescriptor for the file you want to play
     * @param offset the offset into the file where the data to be played starts, in bytes
     * @param length the length in bytes of the data to be played
     * @param mime The mime type of the file. Must be one of the mime types listed above.
     * @throws IllegalArgumentException if the mimeType is not supported.
     * @throws IllegalStateException if called in an invalid state.
     * @hide
     */
    @Override
    public void addTimedTextSource(FileDescriptor fd, long offset, long length, String mime) {
        if (!availableMimeTypeForExternalSource(mime)) {
            throw new IllegalArgumentException("Illegal mimeType for timed text source: " + mime);
        }

        final FileDescriptor dupedFd;
        try {
            dupedFd = Os.dup(fd);
        } catch (ErrnoException ex) {
            Log.e(TAG, ex.getMessage(), ex);
            throw new RuntimeException(ex);
        }

        final MediaFormat fFormat = new MediaFormat();
        fFormat.setString(MediaFormat.KEY_MIME, mime);
        fFormat.setInteger(MediaFormat.KEY_IS_TIMED_TEXT, 1);

        // A MediaPlayer2 created by a VideoView should already have its mSubtitleController set.
        if (mSubtitleController == null) {
            setSubtitleAnchor();
        }

        if (!mSubtitleController.hasRendererFor(fFormat)) {
            // test and add not atomic
            Context context = ActivityThread.currentApplication();
            mSubtitleController.registerRenderer(new SRTRenderer(context, mEventHandler));
        }
        final SubtitleTrack track = mSubtitleController.addTrack(fFormat);
        synchronized (mIndexTrackPairs) {
            mIndexTrackPairs.add(Pair.<Integer, SubtitleTrack>create(null, track));
        }

        getMediaTimeProvider();

        final long offset2 = offset;
        final long length2 = length;
        final HandlerThread thread = new HandlerThread(
                "TimedTextReadThread",
                Process.THREAD_PRIORITY_BACKGROUND + Process.THREAD_PRIORITY_MORE_FAVORABLE);
        thread.start();
        Handler handler = new Handler(thread.getLooper());
        handler.post(new Runnable() {
            private int addTrack() {
                final ByteArrayOutputStream bos = new ByteArrayOutputStream();
                try {
                    Os.lseek(dupedFd, offset2, OsConstants.SEEK_SET);
                    byte[] buffer = new byte[4096];
                    for (long total = 0; total < length2;) {
                        int bytesToRead = (int) Math.min(buffer.length, length2 - total);
                        int bytes = IoBridge.read(dupedFd, buffer, 0, bytesToRead);
                        if (bytes < 0) {
                            break;
                        } else {
                            bos.write(buffer, 0, bytes);
                            total += bytes;
                        }
                    }
                    Handler h = mTimeProvider.mEventHandler;
                    int what = TimeProvider.NOTIFY;
                    int arg1 = TimeProvider.NOTIFY_TRACK_DATA;
                    Pair<SubtitleTrack, byte[]> trackData = Pair.create(track, bos.toByteArray());
                    Message m = h.obtainMessage(what, arg1, 0, trackData);
                    h.sendMessage(m);
                    return MEDIA_INFO_EXTERNAL_METADATA_UPDATE;
                } catch (Exception e) {
                    Log.e(TAG, e.getMessage(), e);
                    return MEDIA_INFO_TIMED_TEXT_ERROR;
                } finally {
                    try {
                        Os.close(dupedFd);
                    } catch (ErrnoException e) {
                        Log.e(TAG, e.getMessage(), e);
                    }
                }
            }

            public void run() {
                int res = addTrack();
                if (mEventHandler != null) {
                    Message m = mEventHandler.obtainMessage(MEDIA_INFO, res, 0, null);
                    mEventHandler.sendMessage(m);
                }
                thread.getLooper().quitSafely();
            }
        });
    }

    /**
     * Returns the index of the audio, video, or subtitle track currently selected for playback,
     * The return value is an index into the array returned by {@link #getTrackInfo()}, and can
     * be used in calls to {@link #selectTrack(int)} or {@link #deselectTrack(int)}.
     *
     * @param trackType should be one of {@link TrackInfo#MEDIA_TRACK_TYPE_VIDEO},
     * {@link TrackInfo#MEDIA_TRACK_TYPE_AUDIO}, or
     * {@link TrackInfo#MEDIA_TRACK_TYPE_SUBTITLE}
     * @return index of the audio, video, or subtitle track currently selected for playback;
     * a negative integer is returned when there is no selected track for {@code trackType} or
     * when {@code trackType} is not one of audio, video, or subtitle.
     * @throws IllegalStateException if called after {@link #close()}
     *
     * @see #getTrackInfo()
     * @see #selectTrack(int)
     * @see #deselectTrack(int)
     */
    @Override
    public int getSelectedTrack(int trackType) {
        if (mSubtitleController != null
                && (trackType == TrackInfo.MEDIA_TRACK_TYPE_SUBTITLE
                || trackType == TrackInfo.MEDIA_TRACK_TYPE_TIMEDTEXT)) {
            SubtitleTrack subtitleTrack = mSubtitleController.getSelectedTrack();
            if (subtitleTrack != null) {
                synchronized (mIndexTrackPairs) {
                    for (int i = 0; i < mIndexTrackPairs.size(); i++) {
                        Pair<Integer, SubtitleTrack> p = mIndexTrackPairs.get(i);
                        if (p.second == subtitleTrack && subtitleTrack.getTrackType() == trackType) {
                            return i;
                        }
                    }
                }
            }
        }

        Parcel request = Parcel.obtain();
        Parcel reply = Parcel.obtain();
        try {
            request.writeInt(INVOKE_ID_GET_SELECTED_TRACK);
            request.writeInt(trackType);
            invoke(request, reply);
            int inbandTrackIndex = reply.readInt();
            synchronized (mIndexTrackPairs) {
                for (int i = 0; i < mIndexTrackPairs.size(); i++) {
                    Pair<Integer, SubtitleTrack> p = mIndexTrackPairs.get(i);
                    if (p.first != null && p.first == inbandTrackIndex) {
                        return i;
                    }
                }
            }
            return -1;
        } finally {
            request.recycle();
            reply.recycle();
        }
    }

    /**
     * Selects a track.
     * <p>
     * If a MediaPlayer2 is in invalid state, it throws an IllegalStateException exception.
     * If a MediaPlayer2 is in <em>Started</em> state, the selected track is presented immediately.
     * If a MediaPlayer2 is not in Started state, it just marks the track to be played.
     * </p>
     * <p>
     * In any valid state, if it is called multiple times on the same type of track (ie. Video,
     * Audio, Timed Text), the most recent one will be chosen.
     * </p>
     * <p>
     * The first audio and video tracks are selected by default if available, even though
     * this method is not called. However, no timed text track will be selected until
     * this function is called.
     * </p>
     * <p>
     * Currently, only timed text tracks or audio tracks can be selected via this method.
     * In addition, the support for selecting an audio track at runtime is pretty limited
     * in that an audio track can only be selected in the <em>Prepared</em> state.
     * </p>
     * @param index the index of the track to be selected. The valid range of the index
     * is 0..total number of track - 1. The total number of tracks as well as the type of
     * each individual track can be found by calling {@link #getTrackInfo()} method.
     * @throws IllegalStateException if called in an invalid state.
     *
     * @see android.media.MediaPlayer2#getTrackInfo
     */
    @Override
    public void selectTrack(int index) {
        selectOrDeselectTrack(index, true /* select */);
    }

    /**
     * Deselect a track.
     * <p>
     * Currently, the track must be a timed text track and no audio or video tracks can be
     * deselected. If the timed text track identified by index has not been
     * selected before, it throws an exception.
     * </p>
     * @param index the index of the track to be deselected. The valid range of the index
     * is 0..total number of tracks - 1. The total number of tracks as well as the type of
     * each individual track can be found by calling {@link #getTrackInfo()} method.
     * @throws IllegalStateException if called in an invalid state.
     *
     * @see android.media.MediaPlayer2#getTrackInfo
     */
    @Override
    public void deselectTrack(int index) {
        selectOrDeselectTrack(index, false /* select */);
    }

    private void selectOrDeselectTrack(int index, boolean select)
            throws IllegalStateException {
        // handle subtitle track through subtitle controller
        populateInbandTracks();

        Pair<Integer,SubtitleTrack> p = null;
        try {
            p = mIndexTrackPairs.get(index);
        } catch (ArrayIndexOutOfBoundsException e) {
            // ignore bad index
            return;
        }

        SubtitleTrack track = p.second;
        if (track == null) {
            // inband (de)select
            selectOrDeselectInbandTrack(p.first, select);
            return;
        }

        if (mSubtitleController == null) {
            return;
        }

        if (!select) {
            // out-of-band deselect
            if (mSubtitleController.getSelectedTrack() == track) {
                mSubtitleController.selectTrack(null);
            } else {
                Log.w(TAG, "trying to deselect track that was not selected");
            }
            return;
        }

        // out-of-band select
        if (track.getTrackType() == TrackInfo.MEDIA_TRACK_TYPE_TIMEDTEXT) {
            int ttIndex = getSelectedTrack(TrackInfo.MEDIA_TRACK_TYPE_TIMEDTEXT);
            synchronized (mIndexTrackPairs) {
                if (ttIndex >= 0 && ttIndex < mIndexTrackPairs.size()) {
                    Pair<Integer,SubtitleTrack> p2 = mIndexTrackPairs.get(ttIndex);
                    if (p2.first != null && p2.second == null) {
                        // deselect inband counterpart
                        selectOrDeselectInbandTrack(p2.first, false);
                    }
                }
            }
        }
        mSubtitleController.selectTrack(track);
    }

    private void selectOrDeselectInbandTrack(int index, boolean select)
            throws IllegalStateException {
        Parcel request = Parcel.obtain();
        Parcel reply = Parcel.obtain();
        try {
            request.writeInt(select? INVOKE_ID_SELECT_TRACK: INVOKE_ID_DESELECT_TRACK);
            request.writeInt(index);
            invoke(request, reply);
        } finally {
            request.recycle();
            reply.recycle();
        }
    }

    /**
     * Releases the resources held by this {@code MediaPlayer2} object.
     *
     * It is considered good practice to call this method when you're
     * done using the MediaPlayer2. In particular, whenever an Activity
     * of an application is paused (its onPause() method is called),
     * or stopped (its onStop() method is called), this method should be
     * invoked to release the MediaPlayer2 object, unless the application
     * has a special need to keep the object around. In addition to
     * unnecessary resources (such as memory and instances of codecs)
     * being held, failure to call this method immediately if a
     * MediaPlayer2 object is no longer needed may also lead to
     * continuous battery consumption for mobile devices, and playback
     * failure for other applications if no multiple instances of the
     * same codec are supported on a device. Even if multiple instances
     * of the same codec are supported, some performance degradation
     * may be expected when unnecessary multiple instances are used
     * at the same time.
     *
     * {@code close()} may be safely called after a prior {@code close()}.
     * This class implements the Java {@code AutoCloseable} interface and
     * may be used with try-with-resources.
     */
    @Override
    public void close() {
        synchronized (mGuard) {
            release();
        }
    }

    // Have to declare protected for finalize() since it is protected
    // in the base class Object.
    @Override
    protected void finalize() throws Throwable {
        if (mGuard != null) {
            mGuard.warnIfOpen();
        }

        close();
        native_finalize();
    }

    private void release() {
        stayAwake(false);
        updateSurfaceScreenOn();
        synchronized (mEventCbLock) {
            mEventCallbackRecords.clear();
        }
        if (mTimeProvider != null) {
            mTimeProvider.close();
            mTimeProvider = null;
        }
        mOnSubtitleDataListener = null;

        // Modular DRM clean up
        mOnDrmConfigHelper = null;
        synchronized (mDrmEventCbLock) {
            mDrmEventCallbackRecords.clear();
        }
        resetDrmState();

        _release();
    }

    private native void _release();

    /* Do not change these values without updating their counterparts
     * in include/media/mediaplayer2.h!
     */
    private static final int MEDIA_NOP = 0; // interface test message
    private static final int MEDIA_PREPARED = 1;
    private static final int MEDIA_PLAYBACK_COMPLETE = 2;
    private static final int MEDIA_BUFFERING_UPDATE = 3;
    private static final int MEDIA_SEEK_COMPLETE = 4;
    private static final int MEDIA_SET_VIDEO_SIZE = 5;
    private static final int MEDIA_STARTED = 6;
    private static final int MEDIA_PAUSED = 7;
    private static final int MEDIA_STOPPED = 8;
    private static final int MEDIA_SKIPPED = 9;
    private static final int MEDIA_NOTIFY_TIME = 98;
    private static final int MEDIA_TIMED_TEXT = 99;
    private static final int MEDIA_ERROR = 100;
    private static final int MEDIA_INFO = 200;
    private static final int MEDIA_SUBTITLE_DATA = 201;
    private static final int MEDIA_META_DATA = 202;
    private static final int MEDIA_DRM_INFO = 210;
    private static final int MEDIA_AUDIO_ROUTING_CHANGED = 10000;

    private TimeProvider mTimeProvider;

    /** @hide */
    @Override
    public MediaTimeProvider getMediaTimeProvider() {
        if (mTimeProvider == null) {
            mTimeProvider = new TimeProvider(this);
        }
        return mTimeProvider;
    }

    private class EventHandler extends Handler {
        private MediaPlayer2Impl mMediaPlayer;

        public EventHandler(MediaPlayer2Impl mp, Looper looper) {
            super(looper);
            mMediaPlayer = mp;
        }

        @Override
        public void handleMessage(Message msg) {
            if (mMediaPlayer.mNativeContext == 0) {
                Log.w(TAG, "mediaplayer2 went away with unhandled events");
                return;
            }
            final int what = msg.arg1;
            final int extra = msg.arg2;
            switch(msg.what) {
            case MEDIA_PREPARED:
                try {
                    scanInternalSubtitleTracks();
                } catch (RuntimeException e) {
                    // send error message instead of crashing;
                    // send error message instead of inlining a call to onError
                    // to avoid code duplication.
                    Message msg2 = obtainMessage(
                            MEDIA_ERROR, MEDIA_ERROR_UNKNOWN, MEDIA_ERROR_UNSUPPORTED, null);
                    sendMessage(msg2);
                }

                synchronized (mEventCbLock) {
                    for (Pair<Executor, EventCallback> cb : mEventCallbackRecords) {
                        cb.first.execute(() -> cb.second.onInfo(
                                mMediaPlayer, 0, MEDIA_INFO_PREPARED, 0));
                    }
                }
                return;

            case MEDIA_DRM_INFO:
                if (msg.obj == null) {
                    Log.w(TAG, "MEDIA_DRM_INFO msg.obj=NULL");
                } else if (msg.obj instanceof Parcel) {
                    // The parcel was parsed already in postEventFromNative
                    final DrmInfoImpl drmInfo;

                    synchronized (mDrmLock) {
                        if (mDrmInfoImpl != null) {
                            drmInfo = mDrmInfoImpl.makeCopy();
                        } else {
                            drmInfo = null;
                        }
                    }

                    // notifying the client outside the lock
                    if (drmInfo != null) {
                        synchronized (mEventCbLock) {
                            for (Pair<Executor, DrmEventCallback> cb : mDrmEventCallbackRecords) {
                                cb.first.execute(() -> cb.second.onDrmInfo(
                                        mMediaPlayer, drmInfo));
                            }
                        }
                    }
                } else {
                    Log.w(TAG, "MEDIA_DRM_INFO msg.obj of unexpected type " + msg.obj);
                }
                return;

            case MEDIA_PLAYBACK_COMPLETE:
                synchronized (mEventCbLock) {
                    for (Pair<Executor, EventCallback> cb : mEventCallbackRecords) {
                        cb.first.execute(() -> cb.second.onInfo(
                                mMediaPlayer, 0, MEDIA_INFO_PLAYBACK_COMPLETE, 0));
                    }
                }
                stayAwake(false);
                return;

            case MEDIA_STOPPED:
                {
                    TimeProvider timeProvider = mTimeProvider;
                    if (timeProvider != null) {
                        timeProvider.onStopped();
                    }
                }
                break;

            case MEDIA_STARTED:
            case MEDIA_PAUSED:
                {
                    TimeProvider timeProvider = mTimeProvider;
                    if (timeProvider != null) {
                        timeProvider.onPaused(msg.what == MEDIA_PAUSED);
                    }
                }
                break;

            case MEDIA_BUFFERING_UPDATE:
                final int percent = msg.arg1;
                synchronized (mEventCbLock) {
                    for (Pair<Executor, EventCallback> cb : mEventCallbackRecords) {
                        cb.first.execute(() -> cb.second.onBufferingUpdate(
                                mMediaPlayer, 0, percent));
                    }
                }
                return;

            case MEDIA_SEEK_COMPLETE:
                synchronized (mEventCbLock) {
                    for (Pair<Executor, EventCallback> cb : mEventCallbackRecords) {
                        cb.first.execute(() -> cb.second.onInfo(
                                mMediaPlayer, 0, MEDIA_INFO_COMPLETE_CALL_SEEK, 0));
                    }
                }
                // fall through

            case MEDIA_SKIPPED:
                {
                    TimeProvider timeProvider = mTimeProvider;
                    if (timeProvider != null) {
                        timeProvider.onSeekComplete(mMediaPlayer);
                    }
                }
                return;

            case MEDIA_SET_VIDEO_SIZE:
                final int width = msg.arg1;
                final int height = msg.arg2;
                synchronized (mEventCbLock) {
                    for (Pair<Executor, EventCallback> cb : mEventCallbackRecords) {
                        cb.first.execute(() -> cb.second.onVideoSizeChanged(
                                mMediaPlayer, 0, width, height));
                    }
                }
                return;

            case MEDIA_ERROR:
                Log.e(TAG, "Error (" + msg.arg1 + "," + msg.arg2 + ")");
                synchronized (mEventCbLock) {
                    for (Pair<Executor, EventCallback> cb : mEventCallbackRecords) {
                        cb.first.execute(() -> cb.second.onError(
                                mMediaPlayer, 0, what, extra));
                        cb.first.execute(() -> cb.second.onInfo(
                                mMediaPlayer, 0, MEDIA_INFO_PLAYBACK_COMPLETE, 0));
                    }
                }
                stayAwake(false);
                return;

            case MEDIA_INFO:
                switch (msg.arg1) {
                    case MEDIA_INFO_VIDEO_TRACK_LAGGING:
                        Log.i(TAG, "Info (" + msg.arg1 + "," + msg.arg2 + ")");
                        break;

                    case MEDIA_INFO_METADATA_UPDATE:
                        try {
                            scanInternalSubtitleTracks();
                        } catch (RuntimeException e) {
                            Message msg2 = obtainMessage(
                                    MEDIA_ERROR, MEDIA_ERROR_UNKNOWN, MEDIA_ERROR_UNSUPPORTED,
                                    null);
                            sendMessage(msg2);
                        }
                        // fall through

                    case MEDIA_INFO_EXTERNAL_METADATA_UPDATE:
                        msg.arg1 = MEDIA_INFO_METADATA_UPDATE;
                        // update default track selection
                        if (mSubtitleController != null) {
                            mSubtitleController.selectDefaultTrack();
                        }
                        break;

                    case MEDIA_INFO_BUFFERING_START:
                    case MEDIA_INFO_BUFFERING_END:
                        TimeProvider timeProvider = mTimeProvider;
                        if (timeProvider != null) {
                            timeProvider.onBuffering(msg.arg1 == MEDIA_INFO_BUFFERING_START);
                        }
                        break;
                }

                synchronized (mEventCbLock) {
                    for (Pair<Executor, EventCallback> cb : mEventCallbackRecords) {
                        cb.first.execute(() -> cb.second.onInfo(
                                mMediaPlayer, 0, what, extra));
                    }
                }
                // No real default action so far.
                return;

            case MEDIA_NOTIFY_TIME:
                    TimeProvider timeProvider = mTimeProvider;
                    if (timeProvider != null) {
                        timeProvider.onNotifyTime();
                    }
                return;

            case MEDIA_TIMED_TEXT:
                final TimedText text;
                if (msg.obj instanceof Parcel) {
                    Parcel parcel = (Parcel)msg.obj;
                    text = new TimedText(parcel);
                    parcel.recycle();
                } else {
                    text = null;
                }

                synchronized (mEventCbLock) {
                    for (Pair<Executor, EventCallback> cb : mEventCallbackRecords) {
                        cb.first.execute(() -> cb.second.onTimedText(mMediaPlayer, 0, text));
                    }
                }
                return;

            case MEDIA_SUBTITLE_DATA:
                OnSubtitleDataListener onSubtitleDataListener = mOnSubtitleDataListener;
                if (onSubtitleDataListener == null) {
                    return;
                }
                if (msg.obj instanceof Parcel) {
                    Parcel parcel = (Parcel) msg.obj;
                    SubtitleData data = new SubtitleData(parcel);
                    parcel.recycle();
                    onSubtitleDataListener.onSubtitleData(mMediaPlayer, data);
                }
                return;

            case MEDIA_META_DATA:
                final TimedMetaData data;
                if (msg.obj instanceof Parcel) {
                    Parcel parcel = (Parcel) msg.obj;
                    data = TimedMetaData.createTimedMetaDataFromParcel(parcel);
                    parcel.recycle();
                } else {
                    data = null;
                }

                synchronized (mEventCbLock) {
                    for (Pair<Executor, EventCallback> cb : mEventCallbackRecords) {
                        cb.first.execute(() -> cb.second.onTimedMetaDataAvailable(
                                mMediaPlayer, 0, data));
                    }
                }
                return;

            case MEDIA_NOP: // interface test message - ignore
                break;

            case MEDIA_AUDIO_ROUTING_CHANGED:
                AudioManager.resetAudioPortGeneration();
                synchronized (mRoutingChangeListeners) {
                    for (NativeRoutingEventHandlerDelegate delegate
                            : mRoutingChangeListeners.values()) {
                        delegate.notifyClient();
                    }
                }
                return;

            default:
                Log.e(TAG, "Unknown message type " + msg.what);
                return;
            }
        }
    }

    /*
     * Called from native code when an interesting event happens.  This method
     * just uses the EventHandler system to post the event back to the main app thread.
     * We use a weak reference to the original MediaPlayer2 object so that the native
     * code is safe from the object disappearing from underneath it.  (This is
     * the cookie passed to native_setup().)
     */
    private static void postEventFromNative(Object mediaplayer2_ref,
                                            int what, int arg1, int arg2, Object obj)
    {
        final MediaPlayer2Impl mp = (MediaPlayer2Impl)((WeakReference)mediaplayer2_ref).get();
        if (mp == null) {
            return;
        }

        switch (what) {
        case MEDIA_INFO:
            if (arg1 == MEDIA_INFO_STARTED_AS_NEXT) {
                new Thread(new Runnable() {
                    @Override
                    public void run() {
                        // this acquires the wakelock if needed, and sets the client side state
                        mp.play();
                    }
                }).start();
                Thread.yield();
            }
            break;

        case MEDIA_DRM_INFO:
            // We need to derive mDrmInfoImpl before prepare() returns so processing it here
            // before the notification is sent to EventHandler below. EventHandler runs in the
            // notification looper so its handleMessage might process the event after prepare()
            // has returned.
            Log.v(TAG, "postEventFromNative MEDIA_DRM_INFO");
            if (obj instanceof Parcel) {
                Parcel parcel = (Parcel)obj;
                DrmInfoImpl drmInfo = new DrmInfoImpl(parcel);
                synchronized (mp.mDrmLock) {
                    mp.mDrmInfoImpl = drmInfo;
                }
            } else {
                Log.w(TAG, "MEDIA_DRM_INFO msg.obj of unexpected type " + obj);
            }
            break;

        case MEDIA_PREPARED:
            // By this time, we've learned about DrmInfo's presence or absence. This is meant
            // mainly for prepareAsync() use case. For prepare(), this still can run to a race
            // condition b/c MediaPlayerNative releases the prepare() lock before calling notify
            // so we also set mDrmInfoResolved in prepare().
            synchronized (mp.mDrmLock) {
                mp.mDrmInfoResolved = true;
            }
            break;

        }

        if (mp.mEventHandler != null) {
            Message m = mp.mEventHandler.obtainMessage(what, arg1, arg2, obj);
            mp.mEventHandler.sendMessage(m);
        }
    }

    private final Object mEventCbLock = new Object();
    private ArrayList<Pair<Executor, EventCallback> > mEventCallbackRecords
        = new ArrayList<Pair<Executor, EventCallback> >();

    /**
     * Register a callback to be invoked when the media source is ready
     * for playback.
     *
     * @param eventCallback the callback that will be run
     * @param executor the executor through which the callback should be invoked
     */
    @Override
    public void registerEventCallback(@NonNull @CallbackExecutor Executor executor,
            @NonNull EventCallback eventCallback) {
        if (eventCallback == null) {
            throw new IllegalArgumentException("Illegal null EventCallback");
        }
        if (executor == null) {
            throw new IllegalArgumentException("Illegal null Executor for the EventCallback");
        }
        synchronized (mEventCbLock) {
            mEventCallbackRecords.add(new Pair(executor, eventCallback));
        }
    }

    /**
     * Unregisters an {@link EventCallback}.
     *
     * @param callback an {@link EventCallback} to unregister
     */
    @Override
    public void unregisterEventCallback(EventCallback callback) {
        synchronized (mEventCbLock) {
            for (Pair<Executor, EventCallback> cb : mEventCallbackRecords) {
                if (cb.second == callback) {
                    mEventCallbackRecords.remove(cb);
                }
            }
        }
    }

    /**
     * Register a callback to be invoked when a track has data available.
     *
     * @param listener the callback that will be run
     *
     * @hide
     */
    @Override
    public void setOnSubtitleDataListener(OnSubtitleDataListener listener) {
        mOnSubtitleDataListener = listener;
    }

    private OnSubtitleDataListener mOnSubtitleDataListener;


    // Modular DRM begin

    /**
     * Register a callback to be invoked for configuration of the DRM object before
     * the session is created.
     * The callback will be invoked synchronously during the execution
     * of {@link #prepareDrm(UUID uuid)}.
     *
     * @param listener the callback that will be run
     */
    @Override
    public void setOnDrmConfigHelper(OnDrmConfigHelper listener)
    {
        synchronized (mDrmLock) {
            mOnDrmConfigHelper = listener;
        } // synchronized
    }

    private OnDrmConfigHelper mOnDrmConfigHelper;

    private final Object mDrmEventCbLock = new Object();
    private ArrayList<Pair<Executor, DrmEventCallback> > mDrmEventCallbackRecords
        = new ArrayList<Pair<Executor, DrmEventCallback> >();

    /**
     * Register a callback to be invoked when the media source is ready
     * for playback.
     *
     * @param eventCallback the callback that will be run
     * @param executor the executor through which the callback should be invoked
     */
    @Override
    public void registerDrmEventCallback(@NonNull @CallbackExecutor Executor executor,
            @NonNull DrmEventCallback eventCallback) {
        if (eventCallback == null) {
            throw new IllegalArgumentException("Illegal null EventCallback");
        }
        if (executor == null) {
            throw new IllegalArgumentException("Illegal null Executor for the EventCallback");
        }
        synchronized (mDrmEventCbLock) {
            mDrmEventCallbackRecords.add(new Pair(executor, eventCallback));
        }
    }

    /**
     * Unregisters a {@link DrmEventCallback}.
     *
     * @param callback a {@link DrmEventCallback} to unregister
     */
    @Override
    public void unregisterDrmEventCallback(DrmEventCallback callback) {
        synchronized (mDrmEventCbLock) {
            for (Pair<Executor, DrmEventCallback> cb : mDrmEventCallbackRecords) {
                if (cb.second == callback) {
                    mDrmEventCallbackRecords.remove(cb);
                    break;
                }
            }
        }
    }


    /**
     * Retrieves the DRM Info associated with the current source
     *
     * @throws IllegalStateException if called before prepare()
     */
    @Override
    public DrmInfo getDrmInfo() {
        DrmInfoImpl drmInfo = null;

        // there is not much point if the app calls getDrmInfo within an OnDrmInfoListenet;
        // regardless below returns drmInfo anyway instead of raising an exception
        synchronized (mDrmLock) {
            if (!mDrmInfoResolved && mDrmInfoImpl == null) {
                final String msg = "The Player has not been prepared yet";
                Log.v(TAG, msg);
                throw new IllegalStateException(msg);
            }

            if (mDrmInfoImpl != null) {
                drmInfo = mDrmInfoImpl.makeCopy();
            }
        }   // synchronized

        return drmInfo;
    }


    /**
     * Prepares the DRM for the current source
     * <p>
     * If {@code OnDrmConfigHelper} is registered, it will be called during
     * preparation to allow configuration of the DRM properties before opening the
     * DRM session. Note that the callback is called synchronously in the thread that called
     * {@code prepareDrm}. It should be used only for a series of {@code getDrmPropertyString}
     * and {@code setDrmPropertyString} calls and refrain from any lengthy operation.
     * <p>
     * If the device has not been provisioned before, this call also provisions the device
     * which involves accessing the provisioning server and can take a variable time to
     * complete depending on the network connectivity.
     * If {@code OnDrmPreparedListener} is registered, prepareDrm() runs in non-blocking
     * mode by launching the provisioning in the background and returning. The listener
     * will be called when provisioning and preparation has finished. If a
     * {@code OnDrmPreparedListener} is not registered, prepareDrm() waits till provisioning
     * and preparation has finished, i.e., runs in blocking mode.
     * <p>
     * If {@code OnDrmPreparedListener} is registered, it is called to indicate the DRM
     * session being ready. The application should not make any assumption about its call
     * sequence (e.g., before or after prepareDrm returns), or the thread context that will
     * execute the listener (unless the listener is registered with a handler thread).
     * <p>
     *
     * @param uuid The UUID of the crypto scheme. If not known beforehand, it can be retrieved
     * from the source through {@code getDrmInfo} or registering a {@code onDrmInfoListener}.
     *
     * @throws IllegalStateException              if called before prepare(), or the DRM was
     *                                            prepared already
     * @throws UnsupportedSchemeException         if the crypto scheme is not supported
     * @throws ResourceBusyException              if required DRM resources are in use
     * @throws ProvisioningNetworkErrorException  if provisioning is required but failed due to a
     *                                            network error
     * @throws ProvisioningServerErrorException   if provisioning is required but failed due to
     *                                            the request denied by the provisioning server
     */
    @Override
    public void prepareDrm(@NonNull UUID uuid)
            throws UnsupportedSchemeException, ResourceBusyException,
                   ProvisioningNetworkErrorException, ProvisioningServerErrorException
    {
        Log.v(TAG, "prepareDrm: uuid: " + uuid + " mOnDrmConfigHelper: " + mOnDrmConfigHelper);

        boolean allDoneWithoutProvisioning = false;

        synchronized (mDrmLock) {

            // only allowing if tied to a protected source; might relax for releasing offline keys
            if (mDrmInfoImpl == null) {
                final String msg = "prepareDrm(): Wrong usage: The player must be prepared and " +
                        "DRM info be retrieved before this call.";
                Log.e(TAG, msg);
                throw new IllegalStateException(msg);
            }

            if (mActiveDrmScheme) {
                final String msg = "prepareDrm(): Wrong usage: There is already " +
                        "an active DRM scheme with " + mDrmUUID;
                Log.e(TAG, msg);
                throw new IllegalStateException(msg);
            }

            if (mPrepareDrmInProgress) {
                final String msg = "prepareDrm(): Wrong usage: There is already " +
                        "a pending prepareDrm call.";
                Log.e(TAG, msg);
                throw new IllegalStateException(msg);
            }

            if (mDrmProvisioningInProgress) {
                final String msg = "prepareDrm(): Unexpectd: Provisioning is already in progress.";
                Log.e(TAG, msg);
                throw new IllegalStateException(msg);
            }

            // shouldn't need this; just for safeguard
            cleanDrmObj();

            mPrepareDrmInProgress = true;

            try {
                // only creating the DRM object to allow pre-openSession configuration
                prepareDrm_createDrmStep(uuid);
            } catch (Exception e) {
                Log.w(TAG, "prepareDrm(): Exception ", e);
                mPrepareDrmInProgress = false;
                throw e;
            }

            mDrmConfigAllowed = true;
        }   // synchronized


        // call the callback outside the lock
        if (mOnDrmConfigHelper != null)  {
            mOnDrmConfigHelper.onDrmConfig(this);
        }

        synchronized (mDrmLock) {
            mDrmConfigAllowed = false;
            boolean earlyExit = false;

            try {
                prepareDrm_openSessionStep(uuid);

                mDrmUUID = uuid;
                mActiveDrmScheme = true;

                allDoneWithoutProvisioning = true;
            } catch (IllegalStateException e) {
                final String msg = "prepareDrm(): Wrong usage: The player must be " +
                        "in the prepared state to call prepareDrm().";
                Log.e(TAG, msg);
                earlyExit = true;
                throw new IllegalStateException(msg);
            } catch (NotProvisionedException e) {
                Log.w(TAG, "prepareDrm: NotProvisionedException");

                // handle provisioning internally; it'll reset mPrepareDrmInProgress
                int result = HandleProvisioninig(uuid);

                // if blocking mode, we're already done;
                // if non-blocking mode, we attempted to launch background provisioning
                if (result != PREPARE_DRM_STATUS_SUCCESS) {
                    earlyExit = true;
                    String msg;

                    switch (result) {
                    case PREPARE_DRM_STATUS_PROVISIONING_NETWORK_ERROR:
                        msg = "prepareDrm: Provisioning was required but failed " +
                                "due to a network error.";
                        Log.e(TAG, msg);
                        throw new ProvisioningNetworkErrorExceptionImpl(msg);

                    case PREPARE_DRM_STATUS_PROVISIONING_SERVER_ERROR:
                        msg = "prepareDrm: Provisioning was required but the request " +
                                "was denied by the server.";
                        Log.e(TAG, msg);
                        throw new ProvisioningServerErrorExceptionImpl(msg);

                    case PREPARE_DRM_STATUS_PREPARATION_ERROR:
                    default: // default for safeguard
                        msg = "prepareDrm: Post-provisioning preparation failed.";
                        Log.e(TAG, msg);
                        throw new IllegalStateException(msg);
                    }
                }
                // nothing else to do;
                // if blocking or non-blocking, HandleProvisioninig does the re-attempt & cleanup
            } catch (Exception e) {
                Log.e(TAG, "prepareDrm: Exception " + e);
                earlyExit = true;
                throw e;
            } finally {
                if (!mDrmProvisioningInProgress) {// if early exit other than provisioning exception
                    mPrepareDrmInProgress = false;
                }
                if (earlyExit) {    // cleaning up object if didn't succeed
                    cleanDrmObj();
                }
            } // finally
        }   // synchronized


        // if finished successfully without provisioning, call the callback outside the lock
        if (allDoneWithoutProvisioning) {
            synchronized (mDrmEventCbLock) {
                for (Pair<Executor, DrmEventCallback> cb : mDrmEventCallbackRecords) {
                    cb.first.execute(() -> cb.second.onDrmPrepared(
                            this, PREPARE_DRM_STATUS_SUCCESS));
                }
            }
        }

    }


    private native void _releaseDrm();

    /**
     * Releases the DRM session
     * <p>
     * The player has to have an active DRM session and be in stopped, or prepared
     * state before this call is made.
     * A {@code reset()} call will release the DRM session implicitly.
     *
     * @throws NoDrmSchemeException if there is no active DRM session to release
     */
    @Override
    public void releaseDrm()
            throws NoDrmSchemeException
    {
        Log.v(TAG, "releaseDrm:");

        synchronized (mDrmLock) {
            if (!mActiveDrmScheme) {
                Log.e(TAG, "releaseDrm(): No active DRM scheme to release.");
                throw new NoDrmSchemeExceptionImpl("releaseDrm: No active DRM scheme to release.");
            }

            try {
                // we don't have the player's state in this layer. The below call raises
                // exception if we're in a non-stopped/prepared state.

                // for cleaning native/mediaserver crypto object
                _releaseDrm();

                // for cleaning client-side MediaDrm object; only called if above has succeeded
                cleanDrmObj();

                mActiveDrmScheme = false;
            } catch (IllegalStateException e) {
                Log.w(TAG, "releaseDrm: Exception ", e);
                throw new IllegalStateException("releaseDrm: The player is not in a valid state.");
            } catch (Exception e) {
                Log.e(TAG, "releaseDrm: Exception ", e);
            }
        }   // synchronized
    }


    /**
     * A key request/response exchange occurs between the app and a license server
     * to obtain or release keys used to decrypt encrypted content.
     * <p>
     * getKeyRequest() is used to obtain an opaque key request byte array that is
     * delivered to the license server.  The opaque key request byte array is returned
     * in KeyRequest.data.  The recommended URL to deliver the key request to is
     * returned in KeyRequest.defaultUrl.
     * <p>
     * After the app has received the key request response from the server,
     * it should deliver to the response to the DRM engine plugin using the method
     * {@link #provideKeyResponse}.
     *
     * @param keySetId is the key-set identifier of the offline keys being released when keyType is
     * {@link MediaDrm#KEY_TYPE_RELEASE}. It should be set to null for other key requests, when
     * keyType is {@link MediaDrm#KEY_TYPE_STREAMING} or {@link MediaDrm#KEY_TYPE_OFFLINE}.
     *
     * @param initData is the container-specific initialization data when the keyType is
     * {@link MediaDrm#KEY_TYPE_STREAMING} or {@link MediaDrm#KEY_TYPE_OFFLINE}. Its meaning is
     * interpreted based on the mime type provided in the mimeType parameter.  It could
     * contain, for example, the content ID, key ID or other data obtained from the content
     * metadata that is required in generating the key request.
     * When the keyType is {@link MediaDrm#KEY_TYPE_RELEASE}, it should be set to null.
     *
     * @param mimeType identifies the mime type of the content
     *
     * @param keyType specifies the type of the request. The request may be to acquire
     * keys for streaming, {@link MediaDrm#KEY_TYPE_STREAMING}, or for offline content
     * {@link MediaDrm#KEY_TYPE_OFFLINE}, or to release previously acquired
     * keys ({@link MediaDrm#KEY_TYPE_RELEASE}), which are identified by a keySetId.
     *
     * @param optionalParameters are included in the key request message to
     * allow a client application to provide additional message parameters to the server.
     * This may be {@code null} if no additional parameters are to be sent.
     *
     * @throws NoDrmSchemeException if there is no active DRM session
     */
    @Override
    @NonNull
    public MediaDrm.KeyRequest getKeyRequest(@Nullable byte[] keySetId, @Nullable byte[] initData,
            @Nullable String mimeType, @MediaDrm.KeyType int keyType,
            @Nullable Map<String, String> optionalParameters)
            throws NoDrmSchemeException
    {
        Log.v(TAG, "getKeyRequest: " +
                " keySetId: " + keySetId + " initData:" + initData + " mimeType: " + mimeType +
                " keyType: " + keyType + " optionalParameters: " + optionalParameters);

        synchronized (mDrmLock) {
            if (!mActiveDrmScheme) {
                Log.e(TAG, "getKeyRequest NoDrmSchemeException");
                throw new NoDrmSchemeExceptionImpl("getKeyRequest: Has to set a DRM scheme first.");
            }

            try {
                byte[] scope = (keyType != MediaDrm.KEY_TYPE_RELEASE) ?
                        mDrmSessionId : // sessionId for KEY_TYPE_STREAMING/OFFLINE
                        keySetId;       // keySetId for KEY_TYPE_RELEASE

                HashMap<String, String> hmapOptionalParameters =
                                                (optionalParameters != null) ?
                                                new HashMap<String, String>(optionalParameters) :
                                                null;

                MediaDrm.KeyRequest request = mDrmObj.getKeyRequest(scope, initData, mimeType,
                                                              keyType, hmapOptionalParameters);
                Log.v(TAG, "getKeyRequest:   --> request: " + request);

                return request;

            } catch (NotProvisionedException e) {
                Log.w(TAG, "getKeyRequest NotProvisionedException: " +
                        "Unexpected. Shouldn't have reached here.");
                throw new IllegalStateException("getKeyRequest: Unexpected provisioning error.");
            } catch (Exception e) {
                Log.w(TAG, "getKeyRequest Exception " + e);
                throw e;
            }

        }   // synchronized
    }


    /**
     * A key response is received from the license server by the app, then it is
     * provided to the DRM engine plugin using provideKeyResponse. When the
     * response is for an offline key request, a key-set identifier is returned that
     * can be used to later restore the keys to a new session with the method
     * {@ link # restoreKeys}.
     * When the response is for a streaming or release request, null is returned.
     *
     * @param keySetId When the response is for a release request, keySetId identifies
     * the saved key associated with the release request (i.e., the same keySetId
     * passed to the earlier {@ link # getKeyRequest} call. It MUST be null when the
     * response is for either streaming or offline key requests.
     *
     * @param response the byte array response from the server
     *
     * @throws NoDrmSchemeException if there is no active DRM session
     * @throws DeniedByServerException if the response indicates that the
     * server rejected the request
     */
    @Override
    public byte[] provideKeyResponse(@Nullable byte[] keySetId, @NonNull byte[] response)
            throws NoDrmSchemeException, DeniedByServerException
    {
        Log.v(TAG, "provideKeyResponse: keySetId: " + keySetId + " response: " + response);

        synchronized (mDrmLock) {

            if (!mActiveDrmScheme) {
                Log.e(TAG, "getKeyRequest NoDrmSchemeException");
                throw new NoDrmSchemeExceptionImpl("getKeyRequest: Has to set a DRM scheme first.");
            }

            try {
                byte[] scope = (keySetId == null) ?
                                mDrmSessionId :     // sessionId for KEY_TYPE_STREAMING/OFFLINE
                                keySetId;           // keySetId for KEY_TYPE_RELEASE

                byte[] keySetResult = mDrmObj.provideKeyResponse(scope, response);

                Log.v(TAG, "provideKeyResponse: keySetId: " + keySetId + " response: " + response +
                        " --> " + keySetResult);


                return keySetResult;

            } catch (NotProvisionedException e) {
                Log.w(TAG, "provideKeyResponse NotProvisionedException: " +
                        "Unexpected. Shouldn't have reached here.");
                throw new IllegalStateException("provideKeyResponse: " +
                        "Unexpected provisioning error.");
            } catch (Exception e) {
                Log.w(TAG, "provideKeyResponse Exception " + e);
                throw e;
            }
        }   // synchronized
    }


    /**
     * Restore persisted offline keys into a new session.  keySetId identifies the
     * keys to load, obtained from a prior call to {@link #provideKeyResponse}.
     *
     * @param keySetId identifies the saved key set to restore
     */
    @Override
    public void restoreKeys(@NonNull byte[] keySetId)
            throws NoDrmSchemeException
    {
        Log.v(TAG, "restoreKeys: keySetId: " + keySetId);

        synchronized (mDrmLock) {

            if (!mActiveDrmScheme) {
                Log.w(TAG, "restoreKeys NoDrmSchemeException");
                throw new NoDrmSchemeExceptionImpl("restoreKeys: Has to set a DRM scheme first.");
            }

            try {
                mDrmObj.restoreKeys(mDrmSessionId, keySetId);
            } catch (Exception e) {
                Log.w(TAG, "restoreKeys Exception " + e);
                throw e;
            }

        }   // synchronized
    }


    /**
     * Read a DRM engine plugin String property value, given the property name string.
     * <p>
     * @param propertyName the property name
     *
     * Standard fields names are:
     * {@link MediaDrm#PROPERTY_VENDOR}, {@link MediaDrm#PROPERTY_VERSION},
     * {@link MediaDrm#PROPERTY_DESCRIPTION}, {@link MediaDrm#PROPERTY_ALGORITHMS}
     */
    @Override
    @NonNull
    public String getDrmPropertyString(@NonNull @MediaDrm.StringProperty String propertyName)
            throws NoDrmSchemeException
    {
        Log.v(TAG, "getDrmPropertyString: propertyName: " + propertyName);

        String value;
        synchronized (mDrmLock) {

            if (!mActiveDrmScheme && !mDrmConfigAllowed) {
                Log.w(TAG, "getDrmPropertyString NoDrmSchemeException");
                throw new NoDrmSchemeExceptionImpl("getDrmPropertyString: Has to prepareDrm() first.");
            }

            try {
                value = mDrmObj.getPropertyString(propertyName);
            } catch (Exception e) {
                Log.w(TAG, "getDrmPropertyString Exception " + e);
                throw e;
            }
        }   // synchronized

        Log.v(TAG, "getDrmPropertyString: propertyName: " + propertyName + " --> value: " + value);

        return value;
    }


    /**
     * Set a DRM engine plugin String property value.
     * <p>
     * @param propertyName the property name
     * @param value the property value
     *
     * Standard fields names are:
     * {@link MediaDrm#PROPERTY_VENDOR}, {@link MediaDrm#PROPERTY_VERSION},
     * {@link MediaDrm#PROPERTY_DESCRIPTION}, {@link MediaDrm#PROPERTY_ALGORITHMS}
     */
    @Override
    public void setDrmPropertyString(@NonNull @MediaDrm.StringProperty String propertyName,
                                     @NonNull String value)
            throws NoDrmSchemeException
    {
        Log.v(TAG, "setDrmPropertyString: propertyName: " + propertyName + " value: " + value);

        synchronized (mDrmLock) {

            if ( !mActiveDrmScheme && !mDrmConfigAllowed ) {
                Log.w(TAG, "setDrmPropertyString NoDrmSchemeException");
                throw new NoDrmSchemeExceptionImpl("setDrmPropertyString: Has to prepareDrm() first.");
            }

            try {
                mDrmObj.setPropertyString(propertyName, value);
            } catch ( Exception e ) {
                Log.w(TAG, "setDrmPropertyString Exception " + e);
                throw e;
            }
        }   // synchronized
    }

    /**
     * Encapsulates the DRM properties of the source.
     */
    public static final class DrmInfoImpl extends DrmInfo {
        private Map<UUID, byte[]> mapPssh;
        private UUID[] supportedSchemes;

        /**
         * Returns the PSSH info of the data source for each supported DRM scheme.
         */
        @Override
        public Map<UUID, byte[]> getPssh() {
            return mapPssh;
        }

        /**
         * Returns the intersection of the data source and the device DRM schemes.
         * It effectively identifies the subset of the source's DRM schemes which
         * are supported by the device too.
         */
        @Override
        public List<UUID> getSupportedSchemes() {
            return Arrays.asList(supportedSchemes);
        }

        private DrmInfoImpl(Map<UUID, byte[]> Pssh, UUID[] SupportedSchemes) {
            mapPssh = Pssh;
            supportedSchemes = SupportedSchemes;
        }

        private DrmInfoImpl(Parcel parcel) {
            Log.v(TAG, "DrmInfoImpl(" + parcel + ") size " + parcel.dataSize());

            int psshsize = parcel.readInt();
            byte[] pssh = new byte[psshsize];
            parcel.readByteArray(pssh);

            Log.v(TAG, "DrmInfoImpl() PSSH: " + arrToHex(pssh));
            mapPssh = parsePSSH(pssh, psshsize);
            Log.v(TAG, "DrmInfoImpl() PSSH: " + mapPssh);

            int supportedDRMsCount = parcel.readInt();
            supportedSchemes = new UUID[supportedDRMsCount];
            for (int i = 0; i < supportedDRMsCount; i++) {
                byte[] uuid = new byte[16];
                parcel.readByteArray(uuid);

                supportedSchemes[i] = bytesToUUID(uuid);

                Log.v(TAG, "DrmInfoImpl() supportedScheme[" + i + "]: " +
                      supportedSchemes[i]);
            }

            Log.v(TAG, "DrmInfoImpl() Parcel psshsize: " + psshsize +
                  " supportedDRMsCount: " + supportedDRMsCount);
        }

        private DrmInfoImpl makeCopy() {
            return new DrmInfoImpl(this.mapPssh, this.supportedSchemes);
        }

        private String arrToHex(byte[] bytes) {
            String out = "0x";
            for (int i = 0; i < bytes.length; i++) {
                out += String.format("%02x", bytes[i]);
            }

            return out;
        }

        private UUID bytesToUUID(byte[] uuid) {
            long msb = 0, lsb = 0;
            for (int i = 0; i < 8; i++) {
                msb |= ( ((long)uuid[i]   & 0xff) << (8 * (7 - i)) );
                lsb |= ( ((long)uuid[i+8] & 0xff) << (8 * (7 - i)) );
            }

            return new UUID(msb, lsb);
        }

        private Map<UUID, byte[]> parsePSSH(byte[] pssh, int psshsize) {
            Map<UUID, byte[]> result = new HashMap<UUID, byte[]>();

            final int UUID_SIZE = 16;
            final int DATALEN_SIZE = 4;

            int len = psshsize;
            int numentries = 0;
            int i = 0;

            while (len > 0) {
                if (len < UUID_SIZE) {
                    Log.w(TAG, String.format("parsePSSH: len is too short to parse " +
                                             "UUID: (%d < 16) pssh: %d", len, psshsize));
                    return null;
                }

                byte[] subset = Arrays.copyOfRange(pssh, i, i + UUID_SIZE);
                UUID uuid = bytesToUUID(subset);
                i += UUID_SIZE;
                len -= UUID_SIZE;

                // get data length
                if (len < 4) {
                    Log.w(TAG, String.format("parsePSSH: len is too short to parse " +
                                             "datalen: (%d < 4) pssh: %d", len, psshsize));
                    return null;
                }

                subset = Arrays.copyOfRange(pssh, i, i+DATALEN_SIZE);
                int datalen = (ByteOrder.nativeOrder() == ByteOrder.LITTLE_ENDIAN) ?
                    ((subset[3] & 0xff) << 24) | ((subset[2] & 0xff) << 16) |
                    ((subset[1] & 0xff) <<  8) |  (subset[0] & 0xff)          :
                    ((subset[0] & 0xff) << 24) | ((subset[1] & 0xff) << 16) |
                    ((subset[2] & 0xff) <<  8) |  (subset[3] & 0xff) ;
                i += DATALEN_SIZE;
                len -= DATALEN_SIZE;

                if (len < datalen) {
                    Log.w(TAG, String.format("parsePSSH: len is too short to parse " +
                                             "data: (%d < %d) pssh: %d", len, datalen, psshsize));
                    return null;
                }

                byte[] data = Arrays.copyOfRange(pssh, i, i+datalen);

                // skip the data
                i += datalen;
                len -= datalen;

                Log.v(TAG, String.format("parsePSSH[%d]: <%s, %s> pssh: %d",
                                         numentries, uuid, arrToHex(data), psshsize));
                numentries++;
                result.put(uuid, data);
            }

            return result;
        }

    };  // DrmInfoImpl

    /**
     * Thrown when a DRM method is called before preparing a DRM scheme through prepareDrm().
     * Extends MediaDrm.MediaDrmException
     */
    public static final class NoDrmSchemeExceptionImpl extends NoDrmSchemeException {
        public NoDrmSchemeExceptionImpl(String detailMessage) {
            super(detailMessage);
        }
    }

    /**
     * Thrown when the device requires DRM provisioning but the provisioning attempt has
     * failed due to a network error (Internet reachability, timeout, etc.).
     * Extends MediaDrm.MediaDrmException
     */
    public static final class ProvisioningNetworkErrorExceptionImpl
            extends ProvisioningNetworkErrorException {
        public ProvisioningNetworkErrorExceptionImpl(String detailMessage) {
            super(detailMessage);
        }
    }

    /**
     * Thrown when the device requires DRM provisioning but the provisioning attempt has
     * failed due to the provisioning server denying the request.
     * Extends MediaDrm.MediaDrmException
     */
    public static final class ProvisioningServerErrorExceptionImpl
            extends ProvisioningServerErrorException {
        public ProvisioningServerErrorExceptionImpl(String detailMessage) {
            super(detailMessage);
        }
    }


    private native void _prepareDrm(@NonNull byte[] uuid, @NonNull byte[] drmSessionId);

        // Modular DRM helpers

    private void prepareDrm_createDrmStep(@NonNull UUID uuid)
            throws UnsupportedSchemeException {
        Log.v(TAG, "prepareDrm_createDrmStep: UUID: " + uuid);

        try {
            mDrmObj = new MediaDrm(uuid);
            Log.v(TAG, "prepareDrm_createDrmStep: Created mDrmObj=" + mDrmObj);
        } catch (Exception e) { // UnsupportedSchemeException
            Log.e(TAG, "prepareDrm_createDrmStep: MediaDrm failed with " + e);
            throw e;
        }
    }

    private void prepareDrm_openSessionStep(@NonNull UUID uuid)
            throws NotProvisionedException, ResourceBusyException {
        Log.v(TAG, "prepareDrm_openSessionStep: uuid: " + uuid);

        // TODO: don't need an open session for a future specialKeyReleaseDrm mode but we should do
        // it anyway so it raises provisioning error if needed. We'd rather handle provisioning
        // at prepareDrm/openSession rather than getKeyRequest/provideKeyResponse
        try {
            mDrmSessionId = mDrmObj.openSession();
            Log.v(TAG, "prepareDrm_openSessionStep: mDrmSessionId=" + mDrmSessionId);

            // Sending it down to native/mediaserver to create the crypto object
            // This call could simply fail due to bad player state, e.g., after play().
            _prepareDrm(getByteArrayFromUUID(uuid), mDrmSessionId);
            Log.v(TAG, "prepareDrm_openSessionStep: _prepareDrm/Crypto succeeded");

        } catch (Exception e) { //ResourceBusyException, NotProvisionedException
            Log.e(TAG, "prepareDrm_openSessionStep: open/crypto failed with " + e);
            throw e;
        }

    }

    // Called from the native side
    @SuppressWarnings("unused")
    private static boolean setAudioOutputDeviceById(AudioTrack track, int deviceId) {
        if (track == null) {
            return false;
        }

        if (deviceId == 0) {
            // Use default routing.
            track.setPreferredDevice(null);
            return true;
        }

        // TODO: Unhide AudioManager.getDevicesStatic.
        AudioDeviceInfo[] outputDevices =
                AudioManager.getDevicesStatic(AudioManager.GET_DEVICES_OUTPUTS);

        boolean success = false;
        for (AudioDeviceInfo device : outputDevices) {
            if (device.getId() == deviceId) {
                track.setPreferredDevice(device);
                success = true;
                break;
            }
        }
        return success;
    }

    // Instantiated from the native side
    @SuppressWarnings("unused")
    private static class StreamEventCallback extends AudioTrack.StreamEventCallback {
        public long mJAudioTrackPtr;
        public long mNativeCallbackPtr;
        public long mUserDataPtr;

        public StreamEventCallback(long jAudioTrackPtr, long nativeCallbackPtr, long userDataPtr) {
            super();
            mJAudioTrackPtr = jAudioTrackPtr;
            mNativeCallbackPtr = nativeCallbackPtr;
            mUserDataPtr = userDataPtr;
        }

        @Override
        public void onTearDown(AudioTrack track) {
            native_stream_event_onTearDown(mNativeCallbackPtr, mUserDataPtr);
        }

        @Override
        public void onStreamPresentationEnd(AudioTrack track) {
            native_stream_event_onStreamPresentationEnd(mNativeCallbackPtr, mUserDataPtr);
        }

        @Override
        public void onStreamDataRequest(AudioTrack track) {
            native_stream_event_onStreamDataRequest(
                    mJAudioTrackPtr, mNativeCallbackPtr, mUserDataPtr);
        }
    }

    private class ProvisioningThread extends Thread {
        public static final int TIMEOUT_MS = 60000;

        private UUID uuid;
        private String urlStr;
        private Object drmLock;
        private MediaPlayer2Impl mediaPlayer;
        private int status;
        private boolean finished;
        public  int status() {
            return status;
        }

        public ProvisioningThread initialize(MediaDrm.ProvisionRequest request,
                                          UUID uuid, MediaPlayer2Impl mediaPlayer) {
            // lock is held by the caller
            drmLock = mediaPlayer.mDrmLock;
            this.mediaPlayer = mediaPlayer;

            urlStr = request.getDefaultUrl() + "&signedRequest=" + new String(request.getData());
            this.uuid = uuid;

            status = PREPARE_DRM_STATUS_PREPARATION_ERROR;

            Log.v(TAG, "HandleProvisioninig: Thread is initialised url: " + urlStr);
            return this;
        }

        public void run() {

            byte[] response = null;
            boolean provisioningSucceeded = false;
            try {
                URL url = new URL(urlStr);
                final HttpURLConnection connection = (HttpURLConnection) url.openConnection();
                try {
                    connection.setRequestMethod("POST");
                    connection.setDoOutput(false);
                    connection.setDoInput(true);
                    connection.setConnectTimeout(TIMEOUT_MS);
                    connection.setReadTimeout(TIMEOUT_MS);

                    connection.connect();
                    response = Streams.readFully(connection.getInputStream());

                    Log.v(TAG, "HandleProvisioninig: Thread run: response " +
                            response.length + " " + response);
                } catch (Exception e) {
                    status = PREPARE_DRM_STATUS_PROVISIONING_NETWORK_ERROR;
                    Log.w(TAG, "HandleProvisioninig: Thread run: connect " + e + " url: " + url);
                } finally {
                    connection.disconnect();
                }
            } catch (Exception e)   {
                status = PREPARE_DRM_STATUS_PROVISIONING_NETWORK_ERROR;
                Log.w(TAG, "HandleProvisioninig: Thread run: openConnection " + e);
            }

            if (response != null) {
                try {
                    mDrmObj.provideProvisionResponse(response);
                    Log.v(TAG, "HandleProvisioninig: Thread run: " +
                            "provideProvisionResponse SUCCEEDED!");

                    provisioningSucceeded = true;
                } catch (Exception e) {
                    status = PREPARE_DRM_STATUS_PROVISIONING_SERVER_ERROR;
                    Log.w(TAG, "HandleProvisioninig: Thread run: " +
                            "provideProvisionResponse " + e);
                }
            }

            boolean succeeded = false;

            boolean hasCallback = false;
            synchronized (mDrmEventCbLock) {
                hasCallback = !mDrmEventCallbackRecords.isEmpty();
            }
            // non-blocking mode needs the lock
            if (hasCallback) {

                synchronized (drmLock) {
                    // continuing with prepareDrm
                    if (provisioningSucceeded) {
                        succeeded = mediaPlayer.resumePrepareDrm(uuid);
                        status = (succeeded) ?
                                PREPARE_DRM_STATUS_SUCCESS :
                                PREPARE_DRM_STATUS_PREPARATION_ERROR;
                    }
                    mediaPlayer.mDrmProvisioningInProgress = false;
                    mediaPlayer.mPrepareDrmInProgress = false;
                    if (!succeeded) {
                        cleanDrmObj();  // cleaning up if it hasn't gone through while in the lock
                    }
                } // synchronized

                // calling the callback outside the lock
                synchronized (mDrmEventCbLock) {
                    for (Pair<Executor, DrmEventCallback> cb : mDrmEventCallbackRecords) {
                        cb.first.execute(() -> cb.second.onDrmPrepared(mediaPlayer, status));
                    }
                }
            } else {   // blocking mode already has the lock

                // continuing with prepareDrm
                if (provisioningSucceeded) {
                    succeeded = mediaPlayer.resumePrepareDrm(uuid);
                    status = (succeeded) ?
                            PREPARE_DRM_STATUS_SUCCESS :
                            PREPARE_DRM_STATUS_PREPARATION_ERROR;
                }
                mediaPlayer.mDrmProvisioningInProgress = false;
                mediaPlayer.mPrepareDrmInProgress = false;
                if (!succeeded) {
                    cleanDrmObj();  // cleaning up if it hasn't gone through
                }
            }

            finished = true;
        }   // run()

    }   // ProvisioningThread

    private int HandleProvisioninig(UUID uuid) {
        // the lock is already held by the caller

        if (mDrmProvisioningInProgress) {
            Log.e(TAG, "HandleProvisioninig: Unexpected mDrmProvisioningInProgress");
            return PREPARE_DRM_STATUS_PREPARATION_ERROR;
        }

        MediaDrm.ProvisionRequest provReq = mDrmObj.getProvisionRequest();
        if (provReq == null) {
            Log.e(TAG, "HandleProvisioninig: getProvisionRequest returned null.");
            return PREPARE_DRM_STATUS_PREPARATION_ERROR;
        }

        Log.v(TAG, "HandleProvisioninig provReq " +
                " data: " + provReq.getData() + " url: " + provReq.getDefaultUrl());

        // networking in a background thread
        mDrmProvisioningInProgress = true;

        mDrmProvisioningThread = new ProvisioningThread().initialize(provReq, uuid, this);
        mDrmProvisioningThread.start();

        int result;

        // non-blocking: this is not the final result
        boolean hasCallback = false;
        synchronized (mDrmEventCbLock) {
            hasCallback = !mDrmEventCallbackRecords.isEmpty();
        }
        if (hasCallback) {
            result = PREPARE_DRM_STATUS_SUCCESS;
        } else {
            // if blocking mode, wait till provisioning is done
            try {
                mDrmProvisioningThread.join();
            } catch (Exception e) {
                Log.w(TAG, "HandleProvisioninig: Thread.join Exception " + e);
            }
            result = mDrmProvisioningThread.status();
            // no longer need the thread
            mDrmProvisioningThread = null;
        }

        return result;
    }

    private boolean resumePrepareDrm(UUID uuid) {
        Log.v(TAG, "resumePrepareDrm: uuid: " + uuid);

        // mDrmLock is guaranteed to be held
        boolean success = false;
        try {
            // resuming
            prepareDrm_openSessionStep(uuid);

            mDrmUUID = uuid;
            mActiveDrmScheme = true;

            success = true;
        } catch (Exception e) {
            Log.w(TAG, "HandleProvisioninig: Thread run _prepareDrm resume failed with " + e);
            // mDrmObj clean up is done by the caller
        }

        return success;
    }

    private void resetDrmState() {
        synchronized (mDrmLock) {
            Log.v(TAG, "resetDrmState: " +
                    " mDrmInfoImpl=" + mDrmInfoImpl +
                    " mDrmProvisioningThread=" + mDrmProvisioningThread +
                    " mPrepareDrmInProgress=" + mPrepareDrmInProgress +
                    " mActiveDrmScheme=" + mActiveDrmScheme);

            mDrmInfoResolved = false;
            mDrmInfoImpl = null;

            if (mDrmProvisioningThread != null) {
                // timeout; relying on HttpUrlConnection
                try {
                    mDrmProvisioningThread.join();
                }
                catch (InterruptedException e) {
                    Log.w(TAG, "resetDrmState: ProvThread.join Exception " + e);
                }
                mDrmProvisioningThread = null;
            }

            mPrepareDrmInProgress = false;
            mActiveDrmScheme = false;

            cleanDrmObj();
        }   // synchronized
    }

    private void cleanDrmObj() {
        // the caller holds mDrmLock
        Log.v(TAG, "cleanDrmObj: mDrmObj=" + mDrmObj + " mDrmSessionId=" + mDrmSessionId);

        if (mDrmSessionId != null)    {
            mDrmObj.closeSession(mDrmSessionId);
            mDrmSessionId = null;
        }
        if (mDrmObj != null) {
            mDrmObj.release();
            mDrmObj = null;
        }
    }

    private static final byte[] getByteArrayFromUUID(@NonNull UUID uuid) {
        long msb = uuid.getMostSignificantBits();
        long lsb = uuid.getLeastSignificantBits();

        byte[] uuidBytes = new byte[16];
        for (int i = 0; i < 8; ++i) {
            uuidBytes[i] = (byte)(msb >>> (8 * (7 - i)));
            uuidBytes[8 + i] = (byte)(lsb >>> (8 * (7 - i)));
        }

        return uuidBytes;
    }

    // Modular DRM end

    /*
     * Test whether a given video scaling mode is supported.
     */
    private boolean isVideoScalingModeSupported(int mode) {
        return (mode == VIDEO_SCALING_MODE_SCALE_TO_FIT ||
                mode == VIDEO_SCALING_MODE_SCALE_TO_FIT_WITH_CROPPING);
    }

    /** @hide */
    static class TimeProvider implements MediaTimeProvider {
        private static final String TAG = "MTP";
        private static final long MAX_NS_WITHOUT_POSITION_CHECK = 5000000000L;
        private static final long MAX_EARLY_CALLBACK_US = 1000;
        private static final long TIME_ADJUSTMENT_RATE = 2;  /* meaning 1/2 */
        private long mLastTimeUs = 0;
        private MediaPlayer2Impl mPlayer;
        private boolean mPaused = true;
        private boolean mStopped = true;
        private boolean mBuffering;
        private long mLastReportedTime;
        // since we are expecting only a handful listeners per stream, there is
        // no need for log(N) search performance
        private MediaTimeProvider.OnMediaTimeListener mListeners[];
        private long mTimes[];
        private Handler mEventHandler;
        private boolean mRefresh = false;
        private boolean mPausing = false;
        private boolean mSeeking = false;
        private static final int NOTIFY = 1;
        private static final int NOTIFY_TIME = 0;
        private static final int NOTIFY_STOP = 2;
        private static final int NOTIFY_SEEK = 3;
        private static final int NOTIFY_TRACK_DATA = 4;
        private HandlerThread mHandlerThread;

        /** @hide */
        public boolean DEBUG = false;

        public TimeProvider(MediaPlayer2Impl mp) {
            mPlayer = mp;
            try {
                getCurrentTimeUs(true, false);
            } catch (IllegalStateException e) {
                // we assume starting position
                mRefresh = true;
            }

            Looper looper;
            if ((looper = Looper.myLooper()) == null &&
                (looper = Looper.getMainLooper()) == null) {
                // Create our own looper here in case MP was created without one
                mHandlerThread = new HandlerThread("MediaPlayer2MTPEventThread",
                      Process.THREAD_PRIORITY_FOREGROUND);
                mHandlerThread.start();
                looper = mHandlerThread.getLooper();
            }
            mEventHandler = new EventHandler(looper);

            mListeners = new MediaTimeProvider.OnMediaTimeListener[0];
            mTimes = new long[0];
            mLastTimeUs = 0;
        }

        private void scheduleNotification(int type, long delayUs) {
            // ignore time notifications until seek is handled
            if (mSeeking && type == NOTIFY_TIME) {
                return;
            }

            if (DEBUG) Log.v(TAG, "scheduleNotification " + type + " in " + delayUs);
            mEventHandler.removeMessages(NOTIFY);
            Message msg = mEventHandler.obtainMessage(NOTIFY, type, 0);
            mEventHandler.sendMessageDelayed(msg, (int) (delayUs / 1000));
        }

        /** @hide */
        public void close() {
            mEventHandler.removeMessages(NOTIFY);
            if (mHandlerThread != null) {
                mHandlerThread.quitSafely();
                mHandlerThread = null;
            }
        }

        /** @hide */
        protected void finalize() {
            if (mHandlerThread != null) {
                mHandlerThread.quitSafely();
            }
        }

        /** @hide */
        public void onNotifyTime() {
            synchronized (this) {
                if (DEBUG) Log.d(TAG, "onNotifyTime: ");
                scheduleNotification(NOTIFY_TIME, 0 /* delay */);
            }
        }

        /** @hide */
        public void onPaused(boolean paused) {
            synchronized(this) {
                if (DEBUG) Log.d(TAG, "onPaused: " + paused);
                if (mStopped) { // handle as seek if we were stopped
                    mStopped = false;
                    mSeeking = true;
                    scheduleNotification(NOTIFY_SEEK, 0 /* delay */);
                } else {
                    mPausing = paused;  // special handling if player disappeared
                    mSeeking = false;
                    scheduleNotification(NOTIFY_TIME, 0 /* delay */);
                }
            }
        }

        /** @hide */
        public void onBuffering(boolean buffering) {
            synchronized (this) {
                if (DEBUG) Log.d(TAG, "onBuffering: " + buffering);
                mBuffering = buffering;
                scheduleNotification(NOTIFY_TIME, 0 /* delay */);
            }
        }

        /** @hide */
        public void onStopped() {
            synchronized(this) {
                if (DEBUG) Log.d(TAG, "onStopped");
                mPaused = true;
                mStopped = true;
                mSeeking = false;
                mBuffering = false;
                scheduleNotification(NOTIFY_STOP, 0 /* delay */);
            }
        }

        /** @hide */
        public void onSeekComplete(MediaPlayer2Impl mp) {
            synchronized(this) {
                mStopped = false;
                mSeeking = true;
                scheduleNotification(NOTIFY_SEEK, 0 /* delay */);
            }
        }

        /** @hide */
        public void onNewPlayer() {
            if (mRefresh) {
                synchronized(this) {
                    mStopped = false;
                    mSeeking = true;
                    mBuffering = false;
                    scheduleNotification(NOTIFY_SEEK, 0 /* delay */);
                }
            }
        }

        private synchronized void notifySeek() {
            mSeeking = false;
            try {
                long timeUs = getCurrentTimeUs(true, false);
                if (DEBUG) Log.d(TAG, "onSeekComplete at " + timeUs);

                for (MediaTimeProvider.OnMediaTimeListener listener: mListeners) {
                    if (listener == null) {
                        break;
                    }
                    listener.onSeek(timeUs);
                }
            } catch (IllegalStateException e) {
                // we should not be there, but at least signal pause
                if (DEBUG) Log.d(TAG, "onSeekComplete but no player");
                mPausing = true;  // special handling if player disappeared
                notifyTimedEvent(false /* refreshTime */);
            }
        }

        private synchronized void notifyTrackData(Pair<SubtitleTrack, byte[]> trackData) {
            SubtitleTrack track = trackData.first;
            byte[] data = trackData.second;
            track.onData(data, true /* eos */, ~0 /* runID: keep forever */);
        }

        private synchronized void notifyStop() {
            for (MediaTimeProvider.OnMediaTimeListener listener: mListeners) {
                if (listener == null) {
                    break;
                }
                listener.onStop();
            }
        }

        private int registerListener(MediaTimeProvider.OnMediaTimeListener listener) {
            int i = 0;
            for (; i < mListeners.length; i++) {
                if (mListeners[i] == listener || mListeners[i] == null) {
                    break;
                }
            }

            // new listener
            if (i >= mListeners.length) {
                MediaTimeProvider.OnMediaTimeListener[] newListeners =
                    new MediaTimeProvider.OnMediaTimeListener[i + 1];
                long[] newTimes = new long[i + 1];
                System.arraycopy(mListeners, 0, newListeners, 0, mListeners.length);
                System.arraycopy(mTimes, 0, newTimes, 0, mTimes.length);
                mListeners = newListeners;
                mTimes = newTimes;
            }

            if (mListeners[i] == null) {
                mListeners[i] = listener;
                mTimes[i] = MediaTimeProvider.NO_TIME;
            }
            return i;
        }

        public void notifyAt(
                long timeUs, MediaTimeProvider.OnMediaTimeListener listener) {
            synchronized(this) {
                if (DEBUG) Log.d(TAG, "notifyAt " + timeUs);
                mTimes[registerListener(listener)] = timeUs;
                scheduleNotification(NOTIFY_TIME, 0 /* delay */);
            }
        }

        public void scheduleUpdate(MediaTimeProvider.OnMediaTimeListener listener) {
            synchronized(this) {
                if (DEBUG) Log.d(TAG, "scheduleUpdate");
                int i = registerListener(listener);

                if (!mStopped) {
                    mTimes[i] = 0;
                    scheduleNotification(NOTIFY_TIME, 0 /* delay */);
                }
            }
        }

        public void cancelNotifications(
                MediaTimeProvider.OnMediaTimeListener listener) {
            synchronized(this) {
                int i = 0;
                for (; i < mListeners.length; i++) {
                    if (mListeners[i] == listener) {
                        System.arraycopy(mListeners, i + 1,
                                mListeners, i, mListeners.length - i - 1);
                        System.arraycopy(mTimes, i + 1,
                                mTimes, i, mTimes.length - i - 1);
                        mListeners[mListeners.length - 1] = null;
                        mTimes[mTimes.length - 1] = NO_TIME;
                        break;
                    } else if (mListeners[i] == null) {
                        break;
                    }
                }

                scheduleNotification(NOTIFY_TIME, 0 /* delay */);
            }
        }

        private synchronized void notifyTimedEvent(boolean refreshTime) {
            // figure out next callback
            long nowUs;
            try {
                nowUs = getCurrentTimeUs(refreshTime, true);
            } catch (IllegalStateException e) {
                // assume we paused until new player arrives
                mRefresh = true;
                mPausing = true; // this ensures that call succeeds
                nowUs = getCurrentTimeUs(refreshTime, true);
            }
            long nextTimeUs = nowUs;

            if (mSeeking) {
                // skip timed-event notifications until seek is complete
                return;
            }

            if (DEBUG) {
                StringBuilder sb = new StringBuilder();
                sb.append("notifyTimedEvent(").append(mLastTimeUs).append(" -> ")
                        .append(nowUs).append(") from {");
                boolean first = true;
                for (long time: mTimes) {
                    if (time == NO_TIME) {
                        continue;
                    }
                    if (!first) sb.append(", ");
                    sb.append(time);
                    first = false;
                }
                sb.append("}");
                Log.d(TAG, sb.toString());
            }

            Vector<MediaTimeProvider.OnMediaTimeListener> activatedListeners =
                new Vector<MediaTimeProvider.OnMediaTimeListener>();
            for (int ix = 0; ix < mTimes.length; ix++) {
                if (mListeners[ix] == null) {
                    break;
                }
                if (mTimes[ix] <= NO_TIME) {
                    // ignore, unless we were stopped
                } else if (mTimes[ix] <= nowUs + MAX_EARLY_CALLBACK_US) {
                    activatedListeners.add(mListeners[ix]);
                    if (DEBUG) Log.d(TAG, "removed");
                    mTimes[ix] = NO_TIME;
                } else if (nextTimeUs == nowUs || mTimes[ix] < nextTimeUs) {
                    nextTimeUs = mTimes[ix];
                }
            }

            if (nextTimeUs > nowUs && !mPaused) {
                // schedule callback at nextTimeUs
                if (DEBUG) Log.d(TAG, "scheduling for " + nextTimeUs + " and " + nowUs);
                mPlayer.notifyAt(nextTimeUs);
            } else {
                mEventHandler.removeMessages(NOTIFY);
                // no more callbacks
            }

            for (MediaTimeProvider.OnMediaTimeListener listener: activatedListeners) {
                listener.onTimedEvent(nowUs);
            }
        }

        public long getCurrentTimeUs(boolean refreshTime, boolean monotonic)
                throws IllegalStateException {
            synchronized (this) {
                // we always refresh the time when the paused-state changes, because
                // we expect to have received the pause-change event delayed.
                if (mPaused && !refreshTime) {
                    return mLastReportedTime;
                }

                try {
                    mLastTimeUs = mPlayer.getCurrentPosition() * 1000L;
                    mPaused = !mPlayer.isPlaying() || mBuffering;
                    if (DEBUG) Log.v(TAG, (mPaused ? "paused" : "playing") + " at " + mLastTimeUs);
                } catch (IllegalStateException e) {
                    if (mPausing) {
                        // if we were pausing, get last estimated timestamp
                        mPausing = false;
                        if (!monotonic || mLastReportedTime < mLastTimeUs) {
                            mLastReportedTime = mLastTimeUs;
                        }
                        mPaused = true;
                        if (DEBUG) Log.d(TAG, "illegal state, but pausing: estimating at " + mLastReportedTime);
                        return mLastReportedTime;
                    }
                    // TODO get time when prepared
                    throw e;
                }
                if (monotonic && mLastTimeUs < mLastReportedTime) {
                    /* have to adjust time */
                    if (mLastReportedTime - mLastTimeUs > 1000000) {
                        // schedule seeked event if time jumped significantly
                        // TODO: do this properly by introducing an exception
                        mStopped = false;
                        mSeeking = true;
                        scheduleNotification(NOTIFY_SEEK, 0 /* delay */);
                    }
                } else {
                    mLastReportedTime = mLastTimeUs;
                }

                return mLastReportedTime;
            }
        }

        private class EventHandler extends Handler {
            public EventHandler(Looper looper) {
                super(looper);
            }

            @Override
            public void handleMessage(Message msg) {
                if (msg.what == NOTIFY) {
                    switch (msg.arg1) {
                    case NOTIFY_TIME:
                        notifyTimedEvent(true /* refreshTime */);
                        break;
                    case NOTIFY_STOP:
                        notifyStop();
                        break;
                    case NOTIFY_SEEK:
                        notifySeek();
                        break;
                    case NOTIFY_TRACK_DATA:
                        notifyTrackData((Pair<SubtitleTrack, byte[]>)msg.obj);
                        break;
                    }
                }
            }
        }
    }
}