<!DOCTYPE HTML>
<html>
<head>
  <title>Test track interfaces when consuming a MediaStream from gUM</title>
  <script src="/tests/SimpleTest/SimpleTest.js"></script>
  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
  <script type="text/javascript" src="manifest.js"></script>
  <script type="text/javascript" src="gUM_support.js"></script>
</head>
<body>
<pre id="test">
<script class="testbody" type="text/javascript">
async function startTest() {
  let steps = 0;
  let audioOnchange = 0;
  let audioOnaddtrack = 0;
  let videoOnchange = 0;
  let videoOnaddtrack = 0;
  let isPlaying = false;
  let element = document.createElement("video");
  let stream;
  try {
    await setupGetUserMediaTestPrefs();
    stream = await navigator.mediaDevices.getUserMedia({audio: true, video: true});
  } catch (err) {
    ok(false, 'Unexpected error fired with: ' + err);
    SimpleTest.finish();
    return;
  }

  element.audioTracks.onaddtrack = function(e) {
    audioOnaddtrack++;
  };

  element.audioTracks.onchange = function(e) {
    audioOnchange++;
  };

  element.videoTracks.onaddtrack = function(e) {
    videoOnaddtrack++;
  };

  element.videoTracks.onchange = function(e) {
    videoOnchange++;
  };

  function checkTrackRemoved() {
    if (isPlaying) {
      is(element.audioTracks.length, 0, 'The length of audioTracks should be 0.');
      is(element.videoTracks.length, 0, 'The length of videoTracks should be 0.');
    }
  }

  element.onended = function() {
    ok(true, 'Event ended is expected to be fired on element.');
    checkTrackRemoved();
    element.onended = null;
    element.onplaying = null;
    element.onpause = null;
    SimpleTest.finish();
  }

  function checkTrackAdded() {
    isPlaying = true;
    is(audioOnaddtrack, 1, 'Calls of onaddtrack on audioTracks should be 1.');
    is(element.audioTracks.length, 1, 'The length of audioTracks should be 1.');
    ok(element.audioTracks[0].enabled, 'Audio track should be enabled as default.');
    is(videoOnaddtrack, 1, 'Calls of onaddtrack on videoTracks should be 1.');
    is(element.videoTracks.length, 1, 'The length of videoTracks should be 1.');
    is(element.videoTracks.selectedIndex, 0,
        'The first video track is set selected as default.');
  }

  function setTrackEnabled(enabled) {
    element.audioTracks[0].enabled = enabled;
    element.videoTracks[0].selected = enabled;
  }

  function checkTrackChanged(calls, enabled) {
    is(audioOnchange, calls, 'Calls of onchange on audioTracks should be '+calls);
    is(element.audioTracks[0].enabled, enabled,
        'Enabled value of the audio track should be ' +enabled);
    is(videoOnchange, calls, 'Calls of onchange on videoTracks should be '+calls);
    is(element.videoTracks[0].selected, enabled,
        'Selected value of the video track should be ' +enabled);
    var index = enabled ? 0 : -1;
    is(element.videoTracks.selectedIndex, index,
        'SelectedIndex of video tracks should be ' +index);
  }

  function onpause() {
    element.onpause = null;
    if (element.ended) {
      return;
    }
    if (steps == 1) {
      setTrackEnabled(false);
      element.onplaying = onplaying;
      element.play();
      steps++;
    } else if (steps == 2) {
      setTrackEnabled(true);
      element.onplaying = onplaying;
      element.play();
      steps++;
    }
  }

  function onplaying() {
    element.onplaying = null;
    if (element.ended) {
      return;
    }
    if (steps == 1) {
      element.onpause = onpause;
      element.pause();
      checkTrackAdded();
    } else if (steps == 2) {
      element.onpause = onpause;
      element.pause();
      checkTrackChanged(1, false);
    } else if (steps == 3) {
      checkTrackChanged(2, true);
      stream.getTracks().forEach(t => t.stop());
    }
  }

  element.onplaying = onplaying;
  element.srcObject = stream;

  steps++;
  await element.play();
}

SimpleTest.waitForExplicitFinish();
SpecialPowers.pushPrefEnv(
  {
    "set": [
      ["media.track.enabled", true]
    ]
  }, startTest);

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