/*///////////////////////////////////////////////////////////////////////////////
//文檔生成日期：2006.3.28
//
//(1)概述：
//類名稱：Audio
//類說明：
//	Audio manager. Contains one player for each sound.
  
//所在子系統：StreamingDemo
//
//系統總描述:
	用兩個Player交替播放從網絡上下載的流媒體。

	上面的代碼可以從
	http://www.cnblogs.com/Files/zhengyun_ustc/StreamingDemo.rar
	下載；
	
	安裝的jar包從
	http://www.cnblogs.com/Files/zhengyun_ustc/StreamingDemo-deployed.rar下載。
	
	本文屬于討論稿，提供的僅僅是建議和測試意見。
	本文還可以從
	http://www.cnblogs.com/zhengyun_ustc/archive/2006/3/28/StreamingDemo.html 得到最新稿。


//(2)歷史記錄:
//創建人: 鄭昀(2006.3.28)
//修改歷史：


//聯系我: Google Talk >> zhengyun@gmail.com
//Blogs:    http://blog.csdn.net/zhengyun_ustc/以及http://www.cnblogs.com/zhengyun_ustc

//(3)版權聲明:
//我這個版本j2me客戶端代碼僅僅允許您借鑒，但不得用于商業用途，除非得到鄭昀本人的授權。本人保留所有權利。

////////////////////////////////////////////////////////////////////*/
package com.ultrapower.model;

import java.io.IOException;
import java.io.InputStream;

import javax.microedition.media.Manager;
import javax.microedition.media.MediaException;
import javax.microedition.media.Player;
import javax.microedition.media.control.VolumeControl;

import com.ultrapower.view.FormPlayer;


/**
 * <p>
 * Audio manager. Contains one player for each sound.
 * </p><p>
 * Implementation note: the format of the sound is hardcoded
 * in method <code>playSound</code>.
 * </p>
 * 
 * @author zhengyun_ustc
 */
public class Audio
{  
  /** The media players */
  protected static Player[] m_sounds = new Player[2];
  /** Current playing player index */
  protected static int m_currentPlayer = -1;
  /** Current prefetching player index */
  protected static int m_currentPrefetcher = -1;
    
  protected static final String TYPE_AMR = "audio/amr";
  
  /**
   * 第一個參數是要播放的媒體資源，
   * 第二個參數是要使用的播放器的序號，是第一個呢還是第二個player，
   * 如果當前這個播放器還沒有創建出來，就新建一個，并直接對媒體資源進行預運算；
   * 如果已經有了的話，那么就直接對媒體進行預運算。
   */
  public synchronized static void prefetchSound(FormPlayer formPlayer
		  ,InputStream input, 
		  int sequence)
  {
	  System.out.println(sequence + 
				">>+==++Enter Audio::prefetchSound");
      // Start sound
	  try
	  {
	      // No player, create one
	      if (m_sounds[sequence] != null)
	      {
			  m_sounds[sequence].stop();
			  m_sounds[sequence].close();
	      }
		  String type = TYPE_AMR;
		  if(input != null)
		  {
			  System.out.println(sequence + 
						">>+==++Audio::prefetchSound createPlayer Begin:" + type);
		      m_sounds[sequence] = 
		        Manager.createPlayer(input, type);
		  }
	  }
	  catch (MediaException e)
	  {
		  System.out.println(sequence + 
					">>prefetchSound>>createPlayer MediaException!");
	      e.printStackTrace();
		  return;
	  }
	  catch (IOException e)
	  {
		  System.out.println(sequence + 
					">>prefetchSound>>createPlayer IOException!");
		  e.printStackTrace();
		  return;
	  }
      
      // Start player
      Player player = m_sounds[sequence];
      if (player != null)
      {
        try
        {
			System.out.println(sequence + 
					">>+==++Audio::prefetchSound realize Begin!");
			player.realize();
			// 添加播放器監聽事件
			player.addPlayerListener(formPlayer);
		    // 設置音量
		    VolumeControl volume = (VolumeControl)
		    player.getControl("VolumeControl");
		    if (volume != null)
		       volume.setLevel(35);// 小點聲!!
		    // 預運算
			System.out.println(sequence + 
					">>+==++Audio::prefetchSound prefetch Begin!");
			player.prefetch();
		    m_currentPrefetcher = sequence;
			System.out.println(sequence + 
			">>+==++Audio::prefetchSound prefetch End!");
        }
        catch (MediaException e)
        {
			System.out.println(sequence + 
					">>prefetchSound>>prefetch IOException!");
			e.printStackTrace();
        }
      }
  }
  
  
  /**
   * 第一個參數是要使用的播放器的序號，是第一個呢還是第二個player，
   * 直接調用該播放器的start方法來播放他已經運算好的媒體資源。
   */
  public synchronized static void playSound(int sequence)
  {
	  System.out.println(sequence + 
		">>+==++Audio::playSound Begin!");
    // Start sound
    {
      // Start player
      Player player = m_sounds[sequence];
      if (player != null)
      {
        try
        {
          player.start();
          m_currentPlayer = sequence;
        }
        catch (MediaException e)
        {
          e.printStackTrace();
        }
      }
    }
	System.out.println(sequence + 
	">>+==++Audio::playSound End!");
  }
  
  /**
   * Stops specified sound if it is playing.
   * @param snd		The id of the sound to stop.
   */
  public synchronized static void stopSound(int snd)
  {
    if (m_sounds[snd] != null)
    {
      try
      {
        m_sounds[snd].stop();
      }
      catch (MediaException e)
      {
        e.printStackTrace();
      }
    }
  }

  /**
   * Stops all sounds and cleans up resources.
   */
  public static void shutdown()
  {
    for (int i = 0; i < m_sounds.length; i++)
    {
      stopSound(i);
      if (m_sounds[i] != null)
      {
        m_sounds[i].deallocate();
      }
    }
  }
  

  /** Prevent instantiation */
  private Audio() {}
}