/*
       Licensed to the Apache Software Foundation (ASF) under one
       or more contributor license agreements.  See the NOTICE file
       distributed with this work for additional information
       regarding copyright ownership.  The ASF licenses this file
       to you under the Apache License, Version 2.0 (the
       "License"); you may not use this file except in compliance
       with the License.  You may obtain a copy of the License at

         http://www.apache.org/licenses/LICENSE-2.0

       Unless required by applicable law or agreed to in writing,
       software distributed under the License is distributed on an
       "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
       KIND, either express or implied.  See the License for the
       specific language governing permissions and limitations
       under the License.
*/
package com.phonegap;

import android.media.AudioManager;
import android.media.MediaPlayer;
import android.media.MediaPlayer.OnCompletionListener;
import android.media.MediaPlayer.OnErrorListener;
import android.media.MediaPlayer.OnPreparedListener;
import android.media.MediaRecorder;
import android.os.Environment;
import android.util.Log;

import java.io.File;
import java.io.IOException;

/**
 * This class implements the audio playback and recording capabilities used by PhoneGap.
 * It is called by the AudioHandler PhoneGap class.
 * Only one file can be played or recorded per class instance.
 * 
 * Local audio files must reside in one of two places:
 * 		android_asset: 		file name must start with /android_asset/sound.mp3
 * 		sdcard:				file name is just sound.mp3
 */
public class AudioPlayer implements OnCompletionListener, OnPreparedListener, OnErrorListener {

    private static final String LOG_TAG = "AudioPlayer";

    // AudioPlayer states
	private static int MEDIA_NONE = 0;
	private static int MEDIA_STARTING = 1;
	private static int MEDIA_RUNNING = 2;
	private static int MEDIA_PAUSED = 3;
	private static int MEDIA_STOPPED = 4;
	
	// AudioPlayer message ids
	private static int MEDIA_STATE = 1;
	private static int MEDIA_DURATION = 2;
    private static int MEDIA_POSITION = 3;
	private static int MEDIA_ERROR = 9;
	
	// Media error codes
    private static int MEDIA_ERR_NONE_ACTIVE    = 0;
    private static int MEDIA_ERR_ABORTED        = 1;
    private static int MEDIA_ERR_NETWORK        = 2;
    private static int MEDIA_ERR_DECODE         = 3;
    private static int MEDIA_ERR_NONE_SUPPORTED = 4;
	
	private AudioHandler handler;					// The AudioHandler object
	private String id;								// The id of this player (used to identify Media object in JavaScript)
	private int state = MEDIA_NONE;					// State of recording or playback
	private String audioFile = null;				// File name to play or record to
	private float duration = -1;					// Duration of audio

	private MediaRecorder recorder = null;			// Audio recording object
	private String tempFile = null;					// Temporary recording file name
	
	private MediaPlayer mPlayer = null;				// Audio player object
	private boolean prepareOnly = false;

	/**
	 * Constructor.
	 * 
	 * @param handler			The audio handler object
	 * @param id				The id of this audio player
	 */
	public AudioPlayer(AudioHandler handler, String id) {
		this.handler = handler;
		this.id = id;
        this.tempFile = Environment.getExternalStorageDirectory().getAbsolutePath() + "/tmprecording.mp3";
	}	

	/**
	 * Destroy player and stop audio playing or recording.
	 */
	public void destroy() {
		
		// Stop any play or record
		if (this.mPlayer != null) {
	        if ((this.state == MEDIA_RUNNING) || (this.state == MEDIA_PAUSED)) {
	            this.mPlayer.stop();
	            this.setState(MEDIA_STOPPED);
	        }
			this.mPlayer.release();
			this.mPlayer = null;
		}
		if (this.recorder != null) {
			this.stopRecording();
			this.recorder.release();
			this.recorder = null;
		}
	}

	/**
	 * Start recording the specified file.
	 * 
	 * @param file				The name of the file
	 */
	public void startRecording(String file) {
		if (this.mPlayer != null) {
			Log.d(LOG_TAG, "AudioPlayer Error: Can't record in play mode.");
			this.handler.sendJavascript("PhoneGap.Media.onStatus('" + this.id + "', "+MEDIA_ERROR+", "+MEDIA_ERR_ABORTED+");");
		}
		
		// Make sure we're not already recording
		else if (this.recorder == null) {
			this.audioFile = file;
			this.recorder = new MediaRecorder();
			this.recorder.setAudioSource(MediaRecorder.AudioSource.MIC);
			this.recorder.setOutputFormat(MediaRecorder.OutputFormat.DEFAULT); // THREE_GPP);
			this.recorder.setAudioEncoder(MediaRecorder.AudioEncoder.DEFAULT); //AMR_NB);
			this.recorder.setOutputFile(this.tempFile);
			try {
				this.recorder.prepare();
				this.recorder.start();
				this.setState(MEDIA_RUNNING);
				return;
			} catch (IllegalStateException e) {
				e.printStackTrace();
			} catch (IOException e) {
				e.printStackTrace();
			}
			this.handler.sendJavascript("PhoneGap.Media.onStatus('" + this.id + "', "+MEDIA_ERROR+", "+MEDIA_ERR_ABORTED+");");			
		}
		else {
		    Log.d(LOG_TAG, "AudioPlayer Error: Already recording.");
			this.handler.sendJavascript("PhoneGap.Media.onStatus('" + this.id + "', "+MEDIA_ERROR+", "+MEDIA_ERR_ABORTED+");");			
		}
	}
	
	/**
	 * Save temporary recorded file to specified name
	 * 
	 * @param file
	 */
	public void moveFile(String file) {
		
		/* this is a hack to save the file as the specified name */
		File f = new File(this.tempFile);
		f.renameTo(new File("/sdcard/" + file));
	}
	
    /**
     * Stop recording and save to the file specified when recording started.
     */
	public void stopRecording() {
		if (this.recorder != null) {
			try{
				if (this.state == MEDIA_RUNNING) {
					this.recorder.stop();
					this.setState(MEDIA_STOPPED);
				}
				this.moveFile(this.audioFile);
			}
			catch (Exception e) {
				e.printStackTrace();
			}
		}
	}	
	
    /**
     * Start or resume playing audio file.
     * 
     * @param file				The name of the audio file.
     */
	public void startPlaying(String file) {
		if (this.recorder != null) {
		    Log.d(LOG_TAG, "AudioPlayer Error: Can't play in record mode.");
			this.handler.sendJavascript("PhoneGap.Media.onStatus('" + this.id + "', "+MEDIA_ERROR+", "+MEDIA_ERR_ABORTED+");");
		}
		
		// If this is a new request to play audio, or stopped
		else if ((this.mPlayer == null) || (this.state == MEDIA_STOPPED)) {
			try {
				// If stopped, then reset player
				if (this.mPlayer != null) {
					this.mPlayer.reset();
				}
				// Otherwise, create a new one
				else {
					this.mPlayer = new MediaPlayer();
				}
				this.audioFile = file;
				
				// If streaming file
				if (this.isStreaming(file)) {
					this.mPlayer.setDataSource(file);
					this.mPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);  
					this.setState(MEDIA_STARTING);
					this.mPlayer.setOnPreparedListener(this);		
					this.mPlayer.prepareAsync();
				}
				
				// If local file
				else {
					if (file.startsWith("/android_asset/")) {
						String f = file.substring(15);
						android.content.res.AssetFileDescriptor fd = this.handler.ctx.getBaseContext().getAssets().openFd(f);
						this.mPlayer.setDataSource(fd.getFileDescriptor(), fd.getStartOffset(), fd.getLength());
					}
					else {
						this.mPlayer.setDataSource("/sdcard/" + file);
					}
					this.setState(MEDIA_STARTING);
					this.mPlayer.setOnPreparedListener(this);		
					this.mPlayer.prepare();

					// Get duration
					this.duration = getDurationInSeconds();
				}
			} 
			catch (Exception e) { 
				e.printStackTrace(); 
				this.handler.sendJavascript("PhoneGap.Media.onStatus('" + this.id + "', "+MEDIA_ERROR+", "+MEDIA_ERR_ABORTED+");");			
			}
		}

		// If we have already have created an audio player
		else {
			
			// If player has been paused, then resume playback
			if ((this.state == MEDIA_PAUSED) || (this.state == MEDIA_STARTING)) {
				this.mPlayer.start();
				this.setState(MEDIA_RUNNING);
			}
			else {
			    Log.d(LOG_TAG, "AudioPlayer Error: startPlaying() called during invalid state: "+this.state);
				this.handler.sendJavascript("PhoneGap.Media.onStatus('" + this.id + "', "+MEDIA_ERROR+", "+MEDIA_ERR_ABORTED+");");			
			}
		}
	} 

	/**
	 * Seek or jump to a new time in the track.
	 */
	public void seekToPlaying(int milliseconds) {
		if (this.mPlayer != null) {
		    this.mPlayer.seekTo(milliseconds);
		    Log.d(LOG_TAG, "Send a onStatus update for the new seek");
		    this.handler.sendJavascript("PhoneGap.Media.onStatus('" + this.id + "', "+MEDIA_POSITION+", "+milliseconds/1000.0f+");");
		}
	}
	
	/**
	 * Pause playing.
	 */
	public void pausePlaying() {
		
		// If playing, then pause
		if (this.state == MEDIA_RUNNING) {
			this.mPlayer.pause();
			this.setState(MEDIA_PAUSED);
		}
		else {
		    Log.d(LOG_TAG, "AudioPlayer Error: pausePlaying() called during invalid state: "+this.state);			
			this.handler.sendJavascript("PhoneGap.Media.onStatus('" + this.id + "', "+MEDIA_ERROR+", "+MEDIA_ERR_NONE_ACTIVE+");");			
		}
	}

    /**
     * Stop playing the audio file.
     */
	public void stopPlaying() {
		if ((this.state == MEDIA_RUNNING) || (this.state == MEDIA_PAUSED)) {
			this.mPlayer.stop();
			this.setState(MEDIA_STOPPED);
		}
		else {
		    Log.d(LOG_TAG, "AudioPlayer Error: stopPlaying() called during invalid state: "+this.state);			
			this.handler.sendJavascript("PhoneGap.Media.onStatus('" + this.id + "', "+MEDIA_ERROR+", "+MEDIA_ERR_NONE_ACTIVE+");");			
		}
	}
	
	/**
	 * Callback to be invoked when playback of a media source has completed.
	 * 
	 * @param mPlayer			The MediaPlayer that reached the end of the file 
	 */
	public void onCompletion(MediaPlayer mPlayer) {
		this.setState(MEDIA_STOPPED);
    } 
	
    /**
     * Get current position of playback.
     * 
     * @return 					position in msec or -1 if not playing
     */
	public long getCurrentPosition() {
		if ((this.state == MEDIA_RUNNING) || (this.state == MEDIA_PAUSED)) {
		    int curPos = this.mPlayer.getCurrentPosition();
		    this.handler.sendJavascript("PhoneGap.Media.onStatus('" + this.id + "', "+MEDIA_POSITION+", "+curPos/1000.0f+");");
			return curPos;
		} 
		else { 
			return -1; 
		}
	}
	
	/**
	 * Determine if playback file is streaming or local.
	 * It is streaming if file name starts with "http://"
	 * 
	 * @param file				The file name
	 * @return					T=streaming, F=local
	 */
	public boolean isStreaming(String file) {
		if (file.contains("http://") || file.contains("https://")) {
			return true;
		} 
		else {
			return false;
		}
	}
	
   /**
     * Get the duration of the audio file.
     * 
     * @param file				The name of the audio file.
     * @return					The duration in msec.
     * 							-1=can't be determined
     * 							-2=not allowed
     */
	public float getDuration(String file) {
		
		// Can't get duration of recording
		if (this.recorder != null) {
			return(-2); // not allowed
		}
		
		// If audio file already loaded and started, then return duration
		if (this.mPlayer != null) {
			return this.duration;
		}
		
		// If no player yet, then create one
		else {
			this.prepareOnly = true;
			this.startPlaying(file);
			
			// This will only return value for local, since streaming
			// file hasn't been read yet.
			return this.duration;
		}
	}

	/**
	 * Callback to be invoked when the media source is ready for playback. 
	 * 
	 * @param mPlayer			The MediaPlayer that is ready for playback 
	 */
	public void onPrepared(MediaPlayer mPlayer) {
		// Listen for playback completion
		this.mPlayer.setOnCompletionListener(this);

		// If start playing after prepared
		if (!this.prepareOnly) {
			
			// Start playing
			this.mPlayer.start();

			// Set player init flag
			this.setState(MEDIA_RUNNING);
		}
		
		// Save off duration
		this.duration = getDurationInSeconds();	
		this.prepareOnly = false;

		// Send status notification to JavaScript
		this.handler.sendJavascript("PhoneGap.Media.onStatus('" + this.id + "', "+MEDIA_DURATION+","+this.duration+");");
		
	}

	/**
	 * By default Android returns the length of audio in mills but we want seconds
	 * 
	 * @return length of clip in seconds
	 */
	private float getDurationInSeconds() {
		return (this.mPlayer.getDuration() / 1000.0f);
	}

	/**
	 * Callback to be invoked when there has been an error during an asynchronous operation
	 *  (other errors will throw exceptions at method call time).
	 *  
	 * @param mPlayer			the MediaPlayer the error pertains to
	 * @param arg1				the type of error that has occurred: (MEDIA_ERROR_UNKNOWN, MEDIA_ERROR_SERVER_DIED)
	 * @param arg2				an extra code, specific to the error.
	 */
	public boolean onError(MediaPlayer mPlayer, int arg1, int arg2) {
	    Log.d(LOG_TAG, "AudioPlayer.onError(" + arg1 + ", " + arg2+")");

		// TODO: Not sure if this needs to be sent?
		this.mPlayer.stop();
		this.mPlayer.release();
		
		// Send error notification to JavaScript
		this.handler.sendJavascript("PhoneGap.Media.onStatus('" + this.id + "', "+MEDIA_ERROR+", "+arg1+");");
		return false;
	}
	
	/**
	 * Set the state and send it to JavaScript.
	 * 
	 * @param state
	 */
	private void setState(int state) {
		if (this.state != state) {
			this.handler.sendJavascript("PhoneGap.Media.onStatus('" + this.id + "', "+MEDIA_STATE+", "+state+");");
		}
		
		this.state = state;
	}

	/**
	 * Set the volume for audio player
	 *
	 * @param volume
	 */
    public void setVolume(float volume) {
        this.mPlayer.setVolume(volume, volume);
    }
}