/*
 * Copyright 2013 Boris Smus. All Rights Reserved.

 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

navigator.getUserMedia =
  navigator.getUserMedia ||
  navigator.webkitGetUserMedia ||
  navigator.mozGetUserMedia ||
  navigator.msGetUserMedia;

function Microphone() {
  this.is_active = false;
  this.canvas = null;

  this.initAudio();
}

Microphone.prototype.initAudio = function () {
  // Start off by initializing a new context.
  context = new (window.AudioContext || window.webkitAudioContext)();

  if (!context.createGain) context.createGain = context.createGainNode;
  if (!context.createDelay) context.createDelay = context.createDelayNode;
  if (!context.createScriptProcessor)
    context.createScriptProcessor = context.createJavaScriptNode;

  // shim layer with setTimeout fallback
  window.requestAnimFrame = (function () {
    return (
      window.requestAnimationFrame ||
      window.webkitRequestAnimationFrame ||
      window.mozRequestAnimationFrame ||
      window.oRequestAnimationFrame ||
      window.msRequestAnimationFrame ||
      function (callback) {
        window.setTimeout(callback, 1000 / 60);
      }
    );
  })();
};

Microphone.prototype.isActive = function () {
  return this.is_active;
};

Microphone.prototype.start = function () {
  this.is_active = true;
  this.canvas = document.querySelector("canvas");

  // TODO(smus): Remove this ugliness.
  var isLocalhost =
    window.location.hostname == "localhost" ||
    window.location.hostname == "127.0.0.1";
  if (window.location.protocol != "https:" && !isLocalhost) {
    alert(
      "HTTPS is required for microphone access, and this site has no SSL cert yet. Sorry!"
    );
  }
  navigator.getUserMedia(
    { audio: true },
    this.onStream.bind(this),
    this.onStreamError.bind(this)
  );
};

Microphone.prototype.stop = function () {
  this.is_active = false;
  this.canvas = null;
};

Microphone.prototype.onStream = function (stream) {
  var input = context.createMediaStreamSource(stream);
  var filter = context.createBiquadFilter();
  filter.frequency.value = 60.0;
  filter.type = "notch";
  filter.Q = 10.0;

  var analyser = context.createAnalyser();
  analyser.fftSize = 2 ** 14;

  // Connect graph.
  input.connect(filter);
  filter.connect(analyser);

  this.analyser = analyser;
  // Setup a timer to visualize some stuff.
  requestAnimFrame(this.visualize.bind(this));
};

Microphone.prototype.onStreamError = function (e) {
  console.error("Error getting microphone", e);
};

Microphone.prototype.visualize = function () {
  if (this.canvas) {
    var drawContext = this.canvas.getContext("2d");
    drawContext.fillStyle = "white";
    drawContext.clearRect(0, 0, this.canvas.width, this.canvas.height);

    var times = new Float32Array(this.analyser.frequencyBinCount);
    this.analyser.getFloatTimeDomainData(times);

    var heightMult = 5;

    var oldOffset;
    for (var i = 0; i < times.length; i++) {
      var value = times[i];
      var percent = value * heightMult + 0.5;
      var height = this.canvas.height * percent;
      var offset = this.canvas.height - height - 1;

      var barWidth = this.canvas.width / times.length;
      //drawContext.fillStyle = 'black';

      if (i > 0) {
        drawContext.beginPath();
        drawContext.moveTo((i - 1) * barWidth, oldOffset);
        drawContext.lineTo(i * barWidth, offset);
        drawContext.stroke();
        drawContext.closePath();
      }
      //drawContext.fillRect(i * barWidth, offset, 1, 1);
      oldOffset = offset;
    }
  }
  requestAnimationFrame(this.visualize.bind(this));
};