/*
    Tango - Central Media Store and Raspberry Pi remote control
    Copyright (C) 2013, 2014  Ulrich Hilger, http://uhilger.de

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */
 

package de.uhilger.tango.store;

import java.io.File;
import java.util.HashMap;
import java.util.Map;
import javax.sound.sampled.AudioFileFormat;
import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioSystem;
import org.tritonus.share.sampled.TAudioFormat;
import org.tritonus.share.sampled.file.TAudioFileFormat;

/**
 * Class <code>Track</code> models an audio file including ID3 metadata. 
 * 
 * @author Ulrich Hilger, <a href="http://dev.uhilger.de" target="_blank">http://dev.uhilger.de</a>
 * @author Published under the terms and conditions of
 * the <a href="http://www.gnu.org/licenses/" target="_blank">GNU Affero General Public License</a>
 *
 * @version 3, February 19, 2012
 */

public class Track {

  /** reference to file of audio track */
  private File trackFile;
  
  /** the time at which playing this track has started */
  private long playStart;
  
  /** reference to metadata information */
  private Map<String, Object> properties;

  /**
   * Create a new object of class <code>Track</code>
   * @param trackFile  the audio file this track object refers to
   */
  public Track(File trackFile) {
    super();
    this.playStart = -1;
    this.trackFile = trackFile;
  }

  /**
   * get the time at which the playing of this track has started
   * @return  number of milliseconds since Jan 1, 1970 denoting the time this tack has 
   * started playing or -1 if it does not play 
   */
  public long getPlayStart() {
    return playStart;
  }

  /**
   * set the time at which the playing of this track has started
   * @param playStart  number of milliseconds since Jan 1, 1970 denoting the time this tack has 
   * started playing or -1 if it does not play 
   */
  public void setPlayStart(long playStart) {
    this.playStart = playStart;
  }

  /**
   * get the file this track refers to
   * @return  the audio file reference
   */
  public File getTrackFile() {
    return trackFile;
  }

  /**
   * set the file this track refers to
   * @param trackFile  the audio file reference to set this track to
   */
  public void setTrackFile(File trackFile) {
    this.trackFile = trackFile;
  }

  /**
   * get the metadata of a given audio file
   *
   * <p>Example<br><pre>
   * properties: {mp3.frequency.hz=44100, title=All Cried Out, 
   * mp3.length.bytes=6301706, comment=, mp3.channels=2, date=1984, 
   * mp3.version.layer=3, mp3.framesize.bytes=414, mp3.id3tag.track=6, 
   * mp3.version.mpeg=1, mp3.bitrate.nominal.bps=128000, mp3.vbr.scale=0, 
   * bitrate=128000, mp3.length.frames=15112, mp3.crc=false, mp3.vbr=false, 
   * album=Alf, mp3.framerate.fps=38.28125, mp3.copyright=false, 
   * mp3.id3tag.v2=java.io.ByteArrayInputStream@7efa96, mp3.version.encoding=MPEG1L3,
   * year=1984, mp3.id3tag.genre=Rock, mp3.header.pos=136, mp3.mode=0,
   * mp3.original=true, vbr=false, mp3.padding=true, duration=394762000, 
   * author=Alison Moyet}
   * </pre></p>
   *
   * @param file File  the audio file to get metadata for
   * @return Map  the properties Map with information such as in above example
   */
  @SuppressWarnings("unchecked")
  private Map<String, Object> getMetadata(File file) {
    Map<String, Object> map = new HashMap<String, Object>();
    try {
      AudioFileFormat audioFileFormat = AudioSystem.getAudioFileFormat(file);
      if (audioFileFormat instanceof TAudioFileFormat) {
        map.putAll(((TAudioFileFormat) audioFileFormat).properties());
      }
      AudioFormat audioFormat = audioFileFormat.getFormat();
      if (audioFormat instanceof TAudioFormat) {
        map.putAll(((TAudioFormat) audioFormat).properties());
      }
    } catch (Exception ex) {
      ex.printStackTrace();
    }
    return map;
  }

  /**
   * get the metadata of the audio file this track refers to
   *
   * <p>Example<br><pre>
   * properties: {mp3.frequency.hz=44100, title=All Cried Out, 
   * mp3.length.bytes=6301706, comment=, mp3.channels=2, date=1984, 
   * mp3.version.layer=3, mp3.framesize.bytes=414, mp3.id3tag.track=6, 
   * mp3.version.mpeg=1, mp3.bitrate.nominal.bps=128000, mp3.vbr.scale=0, 
   * bitrate=128000, mp3.length.frames=15112, mp3.crc=false, mp3.vbr=false, 
   * album=Alf, mp3.framerate.fps=38.28125, mp3.copyright=false, 
   * mp3.id3tag.v2=java.io.ByteArrayInputStream@7efa96, mp3.version.encoding=MPEG1L3,
   * year=1984, mp3.id3tag.genre=Rock, mp3.header.pos=136, mp3.mode=0,
   * mp3.original=true, vbr=false, mp3.padding=true, duration=394762000, 
   * author=Alison Moyet}
   * </pre></p>
   *
   * @return Map  the properties Map with information such as in above example
   */
  public Map<String, Object> getMetadata() {
    if (properties == null) {
      properties = getMetadata(trackFile);
    }
    return properties;
  }

  /**
   * Get the bitrate of this track, i.e. bits per second
   * @return  the bitrate
   */
  public long getBitrate() {
    long bitrate = -1;
    Object o = getMetadata().get("bitrate");
    if (o != null) {
      bitrate = Long.parseLong(o.toString());
    }
    return bitrate;
  }

  /**
   * get the artist of the currently playing song
   * @return String  the artist of the song
   */
  public String getArtist() {
    String artist = "";
    Object o = getMetadata().get("author");
    if (o != null) {
      artist = o.toString().trim();
    }
    return artist;
  }

  /**
   * get the album of the currently playing song
   * @return String  the album of the song
   */
  public String getAlbum() {
    String album = "";
    //if (properties != null) {
    Object o = getMetadata().get("album");
    if (o != null) {
      album = o.toString().trim();
    }
    //}
    return album;
  }

  /**
   * get the title of the currently playing song
   * @return String  the song title
   */
  public String getTitle() {
    String title = "";
    Object o = getMetadata().get("title");
    if (o != null) {
      title = o.toString().trim();
    } else {
      title = trackFile.getName();
    }
    return title;
  }

  /**
   * get the duration of the currently playing song
   *
   * @return long duration in milliseconds
   */
  public long getDuration() {
    long duration = -1;
    Object o = getMetadata().get("duration");
    if (o != null) {
      duration = Long.parseLong(o.toString());
    }
    return duration;
  }

  /**
   * Overridden from class <code>Object</code>
   * @return  the hash code
   * @see java.lang.Object#hashCode() 
   */
  public int hashCode() {
    int hash = 7;
    hash = 97 * hash + (this.trackFile != null ? this.trackFile.hashCode() : 0);
    return hash;
  }

  /**
   * Overridden from class <code>Object</code>
   * @return  true, when this object is equal to the given object 
   * @see java.lang.Object#equals(java.lang.Object) 
   */
  public boolean equals(Object obj) {
    boolean isEqual = false;
    if(obj != null && obj instanceof Track) {
      Track otherTrack = (Track) obj;
      File otherFile = otherTrack.getTrackFile();
      isEqual = otherFile.equals(this.getTrackFile());
    }
    return isEqual;
  }

}