<!DOCTYPE html>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="../../resources/webxr_util.js"></script>
<script src="../../resources/webxr_math_utils.js"></script>
<script src="../../resources/webxr_test_asserts.js"></script>
<script src="../../resources/webxr_test_constants.js"></script>
<script src="../../resources/webxr_test_constants_fake_depth.js"></script>

<script>

const fakeDeviceInitParams = {
  supportedModes: ["immersive-ar"],
  views: VALID_VIEWS,
  supportedFeatures: ALL_FEATURES,
  depthSensingData: DEPTH_SENSING_DATA,
};

const assert_depth_valid_at = function(depthInformation, row, column, deltaRow, deltaColumn) {
  // column and row correspond to the depth buffer coordinates,
  // *not* to normalized view coordinates the getDepthInMeters() expects.

  const expectedValue = getExpectedValueAt(column, row);

  // 1. Normalize:
  let x = (column + deltaColumn) / depthInformation.width;
  let y = (row + deltaRow) / depthInformation.height;

  // 2. Apply the transform that changes the origin and axes:
  x = 1.0 - x;
  y = 1.0 - y;

  const depthValue = depthInformation.getDepthInMeters(x, y);
  assert_approx_equals(depthValue, expectedValue, FLOAT_EPSILON,
                        "Depth value at (" + column + "," + row + "), deltas=(" + deltaColumn + ", " + deltaRow + "), "
                        + "coordinates (" + x + "," + y + ") must match!");
}

const assert_depth_valid = function(depthInformation) {

  assert_true(depthInformation.data instanceof ArrayBuffer,
              "XRCpuDepthInformation.data must be of type `ArrayBuffer`!");

  for(let row = 0; row < depthInformation.height; row++) {
    for(let column = 0; column < depthInformation.width; column++) {
      // middle of the pixel:
      assert_depth_valid_at(depthInformation, row, column, 0.5, 0.5);

      // corners of the pixel:
      assert_depth_valid_at(depthInformation, row, column, FLOAT_EPSILON, FLOAT_EPSILON);
      assert_depth_valid_at(depthInformation, row, column, FLOAT_EPSILON, 1 - FLOAT_EPSILON);
      assert_depth_valid_at(depthInformation, row, column, 1 - FLOAT_EPSILON, FLOAT_EPSILON);
      assert_depth_valid_at(depthInformation, row, column, 1 - FLOAT_EPSILON, 1 - FLOAT_EPSILON);
    }
  }

  // Verify out-of-bounds accesses throw:
  assert_throws_js(RangeError,
                   () => depthInformation.getDepthInMeters(-FLOAT_EPSILON, 0.0),
                   "getDepthInMeters() should throw when run with invalid indices - negative x");
  assert_throws_js(RangeError,
                   () => depthInformation.getDepthInMeters(0.0, -FLOAT_EPSILON),
                   "getDepthInMeters() should throw when run with invalid indices - negative y");
  assert_throws_js(RangeError,
                   () => depthInformation.getDepthInMeters(1+FLOAT_EPSILON, 0.0),
                   "getDepthInMeters() should throw when run with invalid indices - too big x");
  assert_throws_js(RangeError,
                   () => depthInformation.getDepthInMeters(0.0, 1+FLOAT_EPSILON),
                   "getDepthInMeters() should throw when run with invalid indices - too big y");
};

const testCpuOptimizedLuminanceAlpha = function(session, fakeDeviceController, t) {
  return session.requestReferenceSpace('viewer').then((viewerSpace) => {
    let done = false;

    const rafCallback = function(time, frame) {
      const pose = frame.getViewerPose(viewerSpace);
      if(pose) {
        for(const view of pose.views) {
          const depthInformation = frame.getDepthInformation(view);

          t.step(() => {
            assert_not_equals(depthInformation, null, "XRCPUDepthInformation must not be null!");
            assert_approx_equals(depthInformation.width, DEPTH_SENSING_DATA.width, FLOAT_EPSILON);
            assert_approx_equals(depthInformation.height, DEPTH_SENSING_DATA.height, FLOAT_EPSILON);
            assert_approx_equals(depthInformation.rawValueToMeters, DEPTH_SENSING_DATA.rawValueToMeters, FLOAT_EPSILON);
            assert_transform_approx_equals(depthInformation.normDepthBufferFromNormView, DEPTH_SENSING_DATA.normDepthBufferFromNormView);
            assert_depth_valid(depthInformation);
          });
        }
      }

      done = true;
    };

    session.requestAnimationFrame(rafCallback);

    return t.step_wait(() => done);
  });
};

xr_session_promise_test("Ensures depth data is returned and values match expectation, cpu-optimized, luminance-alpha.",
  testCpuOptimizedLuminanceAlpha,
  fakeDeviceInitParams,
  'immersive-ar', {
    'requiredFeatures': ['depth-sensing'],
    depthSensing: VALID_DEPTH_CONFIG_CPU_USAGE,
  });

</script>
