<!DOCTYPE html>
<script src="../resources/testharness.js"></script>
<script src="../resources/testharnessreport.js"></script>
<script src="file:///gen/layout_test_data/mojo/public/js/mojo_bindings.js"></script>
<script src="file:///gen/device/vr/public/mojom/vr_service.mojom.js"></script>
<script src="../external/wpt/resources/chromium/webxr-test.js"></script>
<script src="../xr/resources/xr-test-utils.js"></script>
<canvas id="webgl-canvas"></canvas>

<script>
let testName = "Ensure that the framebuffer given by the WebGL layer is opaque";

let fakeDeviceInitParams = { supportsImmersive: true };

let requestSessionOptions = [
  'immersive-vr',
  'inline'
];

let testFunction =
  (session, t, fakeDeviceController) => new Promise((resolve, reject) => {
  // Session must have a baseLayer or frame requests will be ignored.
  let webglLayer = new XRWebGLLayer(session, gl);
  session.updateRenderState({
    baseLayer: webglLayer,
    outputContext: getOutputContext()
  });

  let xrFramebuffer = webglLayer.framebuffer;

  // Make sure we're starting with a clean error slate.
  assert_equals(gl.getError(), gl.NO_ERROR);

  assert_not_equals(xrFramebuffer, null);
  assert_greater_than(webglLayer.framebufferWidth, 0);
  assert_greater_than(webglLayer.framebufferHeight, 0);

  gl.bindFramebuffer(gl.FRAMEBUFFER, xrFramebuffer);
  assert_equals(gl.getError(), gl.NO_ERROR);

  gl.deleteFramebuffer(xrFramebuffer);
  assert_equals(gl.getError(), gl.INVALID_OPERATION);

  // Make sure the framebuffer is still bound after failed attempt to delete.
  let boundFramebuffer = gl.getParameter(gl.FRAMEBUFFER_BINDING);
  assert_equals(xrFramebuffer, boundFramebuffer);
  assert_equals(gl.getError(), gl.NO_ERROR);

  // Ensure the framebuffer attachment properties cannot be inspected.
  let attachments = [
    gl.COLOR_ATTACHMENT0,
    gl.DEPTH_ATTACHMENT,
    gl.STENCIL_ATTACHMENT,
  ];

  let parameters = [
    gl.FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE,
    gl.FRAMEBUFFER_ATTACHMENT_OBJECT_NAME,
    gl.FRAMEBUFFER_ATTACHMENT_TEXTURE_LEVEL,
    gl.FRAMEBUFFER_ATTACHMENT_TEXTURE_CUBE_MAP_FACE,
  ];

  for (let attachment of attachments) {
    for (let parameter of parameters) {
      let value = gl.getFramebufferAttachmentParameter(gl.FRAMEBUFFER, attachment, parameter);
      assert_equals(value, null);
      assert_equals(gl.getError(), gl.INVALID_OPERATION);
    }
  }

  let width = 64;
  let height = 64;

  // Ensure the framebuffer texture 2D attachmentments cannot be changed.
  var texture = gl.createTexture();
  gl.bindTexture(gl.TEXTURE_2D, texture);
  gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST);
  gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST);
  gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
  gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
  gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, width, height, 0, gl.RGBA, gl.UNSIGNED_BYTE, null);

  gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, texture, 0);
  assert_equals(gl.getError(), gl.INVALID_OPERATION);

  // Ensure the framebuffer renderbuffer attachmentments cannot be changed.
  let renderbuffer = gl.createRenderbuffer();
  gl.bindRenderbuffer(gl.RENDERBUFFER, renderbuffer);
  gl.renderbufferStorage(gl.RENDERBUFFER, gl.DEPTH_COMPONENT16, width, height);
  gl.framebufferRenderbuffer(
    gl.FRAMEBUFFER,
    gl.DEPTH_ATTACHMENT,
    gl.RENDERBUFFER,
    renderbuffer);
  assert_equals(gl.getError(), gl.INVALID_OPERATION);

  gl.renderbufferStorage(gl.RENDERBUFFER, gl.DEPTH_STENCIL, width, height);
  gl.framebufferRenderbuffer(gl.FRAMEBUFFER, gl.DEPTH_STENCIL_ATTACHMENT, gl.RENDERBUFFER, renderbuffer);
  assert_equals(gl.getError(), gl.INVALID_OPERATION);

  // Framebuffer status must be unsupported outside of a XR frame callback.
  assert_equals(gl.checkFramebufferStatus(gl.FRAMEBUFFER), gl.FRAMEBUFFER_UNSUPPORTED);

  session.requestAnimationFrame((time, xrFrame) => {
    // Framebuffer status must be complete inside of a XR frame callback.
    assert_equals(gl.checkFramebufferStatus(gl.FRAMEBUFFER), gl.FRAMEBUFFER_COMPLETE);
    // Finished.
    resolve();
  });
});

xr_session_promise_test(
  testFunction, fakeDeviceInitParams, requestSessionOptions, testName);

</script>