<!DOCTYPE HTML>
<html>
<head>
  <title>Test for the playbackRate property </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>
</head>
<body>
<pre id="test">
<script class="testbody" type='application/javascript'>

let manager = new MediaTestManager;

function rangeCheck(lhs, rhs, threshold) {
  var diff = Math.abs(lhs - rhs);
  if (diff < threshold) {
    return true;
  }
  return false;
}

function checkPlaybackRate(wallclock, media, expected, threshold) {
  if (rangeCheck(media / wallclock, expected, threshold)) {
    return true;
  }
  return false;
}

// Those value are expected to match those at the top of HTMLMediaElement.cpp.
let VERY_SLOW_RATE = 1 / 32,
    SLOW_RATE = 1 / 16,
    FAST_RATE = 16,
    VERY_FAST_RATE = 20,
    NULL_RATE = 0.0;

function ontimeupdate(e) {
  var t = e.target;
  // Skip short files for SoundTouch doesn't work well on small number of samples.
  if (t.gotEnded || t.duration < 2) {
    return;
  }
  t.testedForSlowdown = true;
  if (t.currentTime > t.duration / 2) {
    t.oldCurrentTime = t.currentTime;
    t.timestamp = Date.now();
    var delta = t.oldCurrentTime,
        delta_wallclock = (t.timestamp - t.startTimestamp - t.bufferingTime) / 1000;

    t.preservesPitch = false;
    is(t.preservesPitch, false, t.name + ": If we disable the pitch preservation, it should appear as such.");

    t.bufferingTime = 0;

    is(t.playbackRate, SLOW_RATE, t.name + ": The playback rate shoud be "+SLOW_RATE+".");
    ok(checkPlaybackRate(delta_wallclock, delta, SLOW_RATE, 0.25), t.name + ": We are effectively slowing down playback. (" + delta_wallclock + ", " + delta + ")");
    t.removeEventListener("timeupdate", ontimeupdate);
    t.addEventListener("pause", onpaused);
    t.playbackRate = NULL_RATE;
    t.oldCurrentTime = t.currentTime;
    setTimeout(function() {
      afterNullPlaybackRate(e);
    }, 100);
  }
}

function onpaused(e) {
  var t = e.target;
  t.pausedReceived = true;
}

function afterNullPlaybackRate(e) {
  var t = e.target;

  // skip if we have received 'ended' event or 'ended' event is pending.
  if (t.gotEnded || t.ended) {
    return;
  }

  t.testedForNull = true;

  ok(t.currentTime == t.oldCurrentTime, t.name + ": Current time should not change when playbackRate is null (" + t.currentTime + " " + t.oldCurrentTime + ").");
  ok(!t.paused, t.name + ": The element should not be in paused state.");
  t.removeEventListener("paused", onpaused);
  is(t.pausedReceived, undefined, t.name + ": Paused event should not have been received.");
  t.timestamp = Date.now();
  t.oldCurrentTime = t.currentTime;
  t.playbackRate = VERY_FAST_RATE;
  is(t.playbackRate, VERY_FAST_RATE, t.name + ": Playback rate should be clamped to " + VERY_FAST_RATE + ".");
}

function onended(e) {
  var t = e.target;
  t.gotEnded = true;

  t.bufferingTime = 0;
  // If we got "ended" too early, skip these tests.
  if (t.testedForSlowdown && t.testedForNull) {
    is(t.playbackRate, FAST_RATE, t.name + ": The playback rate should still be "+FAST_RATE+".");
    ok(!t.muted, t.name + ": The audio should be muted when playing at high speed, but should not appear as such.");
    is(t.currentTime, t.duration, t.name + ": Current time should be equal to the duration (not change by playback rate).");
  }
  finish_test(t);
}

function onratechange(e) {
  if (!e.target.ratechangecount) {
    e.target.ratechangecount = 0;
  }
  e.target.ratechangecount++;
}

function finish_test(element) {
  removeNodeAndSource(element);
  manager.finished(element.token);
}

// These two functions handle the case when the playback pauses for buffering. It
// adjusts the timestamps to be accurate. Despite the fact that the web servers
// is supposed to be on the same machine, buffering pauses can occur (rarely,
// but still).
function onplaying(e) {
  var t = e.target;
  if (t.bufferingTimestamp != undefined) {
    t.bufferingTime += (Date.now() - t.bufferingTimestamp);
    t.bufferingTimestamp = undefined;
  }
}

function onwaiting(e) {
  var t = e.target;
  t.bufferingTimestamp = Date.now();
}

function onvolumechange(e) {
  ok(false, e.target.name + ": We should not receive a volumechange event when changing the playback rate.");
}

function startTest(test, token) {
  let elemType = /^audio/.test(test.type) ? "audio" : "video";
  let element = document.createElement(elemType);
  element.src = test.name;
  element.name = test.name;
  element.preload = "metadata";
  element.token = token;
  element.controls = true;
  element.bufferingTime = 0;
  document.body.appendChild(element);
  element.addEventListener("ratechange", onratechange);
  element.addEventListener("timeupdate", ontimeupdate);
  element.addEventListener("ended", onended);
  element.addEventListener("waiting", onwaiting);
  element.addEventListener("playing", onplaying);
  element.addEventListener("volumechange", onvolumechange);
  manager.started(token);
  element.startTimestamp = Date.now();
  is(element.preservesPitch, true, test.name + ": Pitch preservation should be enabled by default.");
  element.addEventListener("loadedmetadata", function() {
    is(element.playbackRate, 1.0, test.name + ": playbackRate should be initially 1.0");
    is(element.defaultPlaybackRate, 1.0, test.name + ": defaultPlaybackRate should be initially 1.0");
    element.playbackRate = VERY_SLOW_RATE;
    is(element.playbackRate, VERY_SLOW_RATE, test.name + ": PlaybackRate should be " + VERY_SLOW_RATE + ".");
    element.play();
    element.playbackRate = SLOW_RATE;
  });
}

manager.runTests(gPlayedTests, startTest);

</script>
</pre>
<div id="elements">
</div>
</body>
</html>
