signal-desktop/js/views/recorder_view.js

(function() {
  'use strict';
  window.Whisper = window.Whisper || {};

  Whisper.RecorderView = Whisper.View.extend({
    className: 'recorder clearfix',
    templateName: 'recorder',
    initialize: function() {
      this.startTime = Date.now();
      this.interval = setInterval(this.updateTime.bind(this), 1000);
      this.start();
    },
    events: {
      'click .close': 'close',
      'click .finish': 'finish',
      close: 'close',
    },
    updateTime: function() {
      var duration = moment.duration(Date.now() - this.startTime, 'ms');
      var minutes = '' + Math.trunc(duration.asMinutes());
      var seconds = '' + duration.seconds();
      if (seconds.length < 2) {
        seconds = '0' + seconds;
      }
      this.$('.time').text(minutes + ':' + seconds);
    },
    close: function() {
      // Note: the 'close' event can be triggered by InboxView, when the user clicks
      //   anywhere outside the recording pane.

      if (this.recorder.isRecording()) {
        this.recorder.cancelRecording();
      }
      if (this.interval) {
        clearInterval(this.interval);
      }
      if (this.source) {
        this.source.disconnect();
      }
      if (this.context) {
        this.context.close().then(function() {
          console.log('audio context closed');
        });
      }
      this.remove();
      this.trigger('closed');
    },
    finish: function() {
      this.recorder.finishRecording();
      this.close();
    },
    handleBlob: function(recorder, blob) {
      if (blob) {
        this.trigger('send', blob);
      }
    },
    start: function() {
      this.context = new AudioContext();
      this.input = this.context.createGain();
      this.recorder = new WebAudioRecorder(this.input, {
        encoding: 'mp3',
        workerDir: 'js/', // must end with slash
      });
      this.recorder.onComplete = this.handleBlob.bind(this);
      this.recorder.onError = this.onError;
      navigator.webkitGetUserMedia(
        { audio: true },
        function(stream) {
          this.source = this.context.createMediaStreamSource(stream);
          this.source.connect(this.input);
        }.bind(this),
        this.onError.bind(this)
      );
      this.recorder.startRecording();
    },
    onError: function(error) {
      console.log(error.stack);
      this.close();
    },
  });
})();