SoundPlayer = function() {
  this.audio = new Audio();
  this.audio.preload = 'auto';
  this.audio.autoplay = true;
  this.audio.addEventListener('ended', function() {
    this.audio.src = '';
  }.bind(this));

  this.isLoading = false;
  this.isPlaying = false;
  this.volume = 1;
  this.sounds = [];
};

SoundPlayer.prototype.setVolume = function(volume) {
  this.volume = Math.max(0, Math.min(1, volume));

  this.sounds.forEach(function(sound) {
    sound.volume = this.volume;
  }, this);
};

SoundPlayer.prototype.getVolume = function() {
  return this.volume;
};


SoundPlayer.prototype.play = function(url, callback) {
  return SoundPlayer.prototype.playSequence([url], callback);
};

SoundPlayer.prototype.playSequence = function(soundsUrls, callback) {
  if (this.isPlaying || this.isLoading) {
    return false;
  }

  var loaded = soundsUrls.length;
  var index = 0;

  var onCanPlayThroughListener = function() {
    loaded--;
    if (loaded <= 0) {
      this.isLoading = false;
      play(index);
    }
  }.bind(this);

  var onEndedListener = function() {
    index++;

    if (index < soundsUrls.length) {
      play(index);
    } else {
      this.isPlaying = false;
      this.sounds = [];
      if (_.isFunction(callback)) {
        callback();
      }
    }
  }.bind(this);

  var load = function() {
    this.isLoading = true;

    soundsUrls.forEach(function(soundUrl) {
      var sound = new Audio();
      sound.preload = 'auto';
      sound.volume = this.getVolume();
      sound.addEventListener('canplaythrough', onCanPlayThroughListener);
      sound.addEventListener('ended', onEndedListener);
      this.sounds.push(sound);
      sound.src = soundUrl;
    }, this);
  }.bind(this);

  var play = function(index) {
    this.isPlaying = true;
    this.sounds[index].play();
  }.bind(this);

  load();

  return true;
};

var sp = new SoundPlayer();
sp.playSequence([
  '/sounds/first.wav',
  '/sounds/second.wav'
]);