<!DOCTYPE HTML>
<html>
<head>
  <title>Test GainNode</title>
  <script src="/tests/SimpleTest/SimpleTest.js"></script>
  <script type="text/javascript" src="webaudio.js"></script>
  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
</head>
<body>
<pre id="test">
<script class="testbody" type="text/javascript">

var gTest = {
  length: 2048,
  numberOfChannels: 1,
  createGraph(context) {

    var gain = new GainNode(context);
    ok(gain.gain, "The audioparam member must exist");
    is(gain.gain.value, 1.0, "Correct initial value");
    is(gain.gain.defaultValue, 1.0, "Correct default value");
    gain.gain.value = 0.5;
    is(gain.gain.value, 0.5, "Correct initial value");
    is(gain.gain.defaultValue, 1.0, "Correct default value");

    gain = new GainNode(context, { gain: 0.5 });
    ok(gain.gain, "The audioparam member must exist");
    is(gain.gain.value, 0.5, "Correct initial value");
    is(gain.gain.defaultValue, 1.0, "Correct default value");
    gain.gain.value = 0.5;
    is(gain.gain.value, 0.5, "Correct initial value");
    is(gain.gain.defaultValue, 1.0, "Correct default value");

    var buffer = context.createBuffer(1, 2048, context.sampleRate);
    for (var i = 0; i < 2048; ++i) {
      buffer.getChannelData(0)[i] = Math.sin(440 * 2 * Math.PI * i / context.sampleRate);
    }

    var source = context.createBufferSource();
    source.buffer = buffer;

    gain = context.createGain();
    source.connect(gain);

    ok(gain.gain, "The audioparam member must exist");
    is(gain.gain.value, 1.0, "Correct initial value");
    is(gain.gain.defaultValue, 1.0, "Correct default value");
    gain.gain.value = 0.5;
    is(gain.gain.value, 0.5, "Correct initial value");
    is(gain.gain.defaultValue, 1.0, "Correct default value");
    is(gain.channelCount, 2, "gain node has 2 input channels by default");
    is(gain.channelCountMode, "max", "Correct channelCountMode for the gain node");
    is(gain.channelInterpretation, "speakers", "Correct channelCountInterpretation for the gain node");

    source.start(0);
    return gain;
  },
  createExpectedBuffers(context) {
    var expectedBuffer = context.createBuffer(1, 2048, context.sampleRate);
    for (var i = 0; i < 2048; ++i) {
      expectedBuffer.getChannelData(0)[i] = Math.sin(440 * 2 * Math.PI * i / context.sampleRate) / 2;
    }
    return expectedBuffer;
  },
};

runTest();

</script>
</pre>
</body>
</html>
