// Near Infinity - An Infinity Engine Browser and Editor
// Copyright (C) 2001 - 2005 Jon Olav Hauglid
// See LICENSE.txt for license information

package org.infinity.resource.sound;

import java.io.ByteArrayInputStream;

import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.DataLine;
import javax.sound.sampled.SourceDataLine;
import javax.sound.sampled.UnsupportedAudioFileException;

public class AudioPlayer
{
  private static final byte buffer[] = new byte[8196];

  private AudioFormat audioFormat;
  private SourceDataLine dataLine;
  private boolean playing = true, stopped = true;

  /**
   * Starts playback of audio data associated with the specified audio buffer.
   * @param audioBuffer AudioBuffer object containing audio data.
   * @throws Exception On error
   */
  public void play(AudioBuffer audioBuffer) throws Exception
  {
    if (audioBuffer == null || audioBuffer.getAudioData() == null)
      return;

    setPlaying(true);
    setStopped(false);
    AudioInputStream ais = null;
    try {
      ais = AudioSystem.getAudioInputStream(new ByteArrayInputStream(audioBuffer.getAudioData()));
    } catch (UnsupportedAudioFileException e) {
      throw new Exception("Unsupported audio format");
    }

    if (dataLine == null || !ais.getFormat().matches(audioFormat)) {
      audioFormat = ais.getFormat();
      DataLine.Info info = new DataLine.Info(SourceDataLine.class, audioFormat);
      if (!AudioSystem.isLineSupported(info)) {
        throw new Exception("Unsupported audio format");
      }
      dataLine = (SourceDataLine)AudioSystem.getLine(info);
      dataLine.open(ais.getFormat(), 16384);
    }
    dataLine.start();

    while (isPlaying()) {
      int numBytesRead = ais.read(buffer, 0, buffer.length);
      if (numBytesRead < 0)
        break;
      dataLine.write(buffer, 0, numBytesRead);
    }
    ais.close();

    if (!isPlaying()) {
      dataLine.drain();
    }

    setStopped(true);
  }

  /**
   * Stops audio playback.
   */
  public void stopPlay()
  {
    setPlaying(false);
    while (!isStopped()) {
      try {
        Thread.sleep(50L);
      } catch (InterruptedException e) {
      }
    }
    try {
      Thread.sleep(150L);
    } catch (InterruptedException e) {
    }
    dataLine = null;
  }

  private synchronized void setPlaying(boolean b)
  {
    if (b != playing)
      playing = b;
  }

  private boolean isPlaying()
  {
    return playing;
  }

  private synchronized void setStopped(boolean b)
  {
    if (b != stopped)
      stopped = b;
  }

  private boolean isStopped()
  {
    return stopped;
  }
}