<!DOCTYPE html>
<html>
  <head>
    <title>
      Test Start Grain with Delayed Buffer Setting
    </title>
    <script src="/resources/testharness.js"></script>
    <script src="/resources/testharnessreport.js"></script>
    <script src="/webaudio/resources/audit-util.js"></script>
    <script src="/webaudio/resources/audit.js"></script>
  </head>
  <body>
    <script id="layout-test-code">
      let audit = Audit.createTaskRunner();
      let context;
      let source;
      let buffer;
      let renderedData;

      let sampleRate = 44100;

      let testDurationSec = 1;
      let testDurationSamples = testDurationSec * sampleRate;
      let startTime = 0.9 * testDurationSec;

      audit.define(
          'Test setting the source buffer after starting the grain',
          function(task, should) {
            context =
                new OfflineAudioContext(1, testDurationSamples, sampleRate);

            buffer = createConstantBuffer(context, testDurationSamples, 1);
            source = context.createBufferSource();
            source.connect(context.destination);

            // Start the source BEFORE we set the buffer. The grain offset and
            // duration aren't important, as long as we specify some offset.
            source.start(startTime, .1);
            source.buffer = buffer;

            // Render it!
            context.startRendering()
                .then(function(buffer) {
                  checkResult(buffer, should);
                })
                .then(task.done.bind(task));
            ;
          });

      function checkResult(buffer, should) {
        let success = false;

        renderedData = buffer.getChannelData(0);

        // Check that the rendered data is not all zeroes.  Any non-zero data
        // means the test passed.
        let startFrame = Math.round(startTime * sampleRate);
        for (k = 0; k < renderedData.length; ++k) {
          if (renderedData[k]) {
            success = true;
            break;
          }
        }

        should(success, 'Buffer was played').beTrue();
      }

      audit.run();
    </script>
  </body>
</html>
