package org.daisy.pipeline.tts.calabash.impl;
   
   import java.io.File;
   import java.util.concurrent.atomic.AtomicReference;
   
   import javax.sound.sampled.AudioInputStream;
   
   import org.daisy.pipeline.audio.AudioClip;
   import org.daisy.pipeline.tts.AudioFootprintMonitor;
  
  /**
   * ContiguousPCMs are the message objects sent from TTS processors to the
   * encoders. Every ContiguousPCM contains a AudioInputStream and attributes
   * related to the URI of the sound file to produce.
   */
  class ContiguousPCM implements Comparable<ContiguousPCM> {
  
  	static ContiguousPCM EndOfQueue = new ContiguousPCM();
  
  	ContiguousPCM() {
  		mEncodingTimeApprox = -1;
  		mSizeInBytes = minByteSize();
  	}
  
  	boolean isEndOfQueue() {
  		return (mEncodingTimeApprox == -1);
  	}
  
  	ContiguousPCM(AudioInputStream audio, File destdir, String destFilePrefix) {
  		mAudio = audio;
  		mDestDir = destdir;
  		mDestFilePrefix = destFilePrefix;
  		mDestFile = new AtomicReference<>();
  		int size = AudioFootprintMonitor.getFootprint(audio);
  		mSizeInBytes = minByteSize() + size;
  		mEncodingTimeApprox = size / audio.getFormat().getSampleSizeInBits();
  	}
  
  	@Override
  	public int compareTo(ContiguousPCM o) {
  		return (o.mEncodingTimeApprox - mEncodingTimeApprox); //descending order => biggest chunks will be polled first
  	}
  
  	String getDestinationFilePrefix() {
  		return mDestFilePrefix;
  	}
  
  	File getDestinationDirectory() {
  		return mDestDir;
  	}
  
  	AudioInputStream getAudio() {
  		return mAudio;
  	}
  
  	AtomicReference<AudioClip> getDestinationFile() {
  		return mDestFile;
  	}
  
  	public int sizeInBytes() {
  		return mSizeInBytes;
  	}
  
  	private int minByteSize() {
  		return 500;//rough approximation of an empty ContiguousPCM's memory footprint
  	}
  
  	private AudioInputStream mAudio;
  	private int mEncodingTimeApprox; //used for sorting
  	private int mSizeInBytes; //used for monitoring the memory footprint
  	private File mDestDir;
  	private String mDestFilePrefix;
  	private AtomicReference<AudioClip> mDestFile;
  
  }