<!DOCTYPE HTML>
<title>CSS Test (Transforms): Hit Testing</title>
<link rel="author" title="L. David Baron" href="https://dbaron.org/">
<link rel="author" title="Google" href="http://www.google.com/">
<link rel="help" href="https://www.w3.org/TR/css-transforms-1/#transform-property">
<link rel="help" href="https://www.w3.org/TR/css-transforms-2/#individual-transforms">
<meta name="flags" content="dom">
<style>

html, body {
  height: 100%;
  width: 100%;
  margin: 0;
  padding: 0;
  border: none;
}

body { margin: 50px; }

</style>
<script>

let body_x_margin = 50;
let body_y_margin = 50;

</script>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>

<body>
<script>

class Point {
  constructor(x, y) {
    this.x = x;
    this.y = y;
  }
}

let simple_tests = [
  // In this list of tests, test_points_inside and test_points_outside
  // are relative to the element's untransformed origin (top, left).
  {
    description: "rectangle with 'translate' and 'rotate'",
    styles: "width: 100px; height: 50px; translate: 30px; rotate: 20deg;",
    test_points_inside: [
      new Point(28, 32),
      new Point(44, -10),
      new Point(133, 22),
      new Point(117, 64),
      new Point(65, 27),
    ],
    test_points_outside: [
      new Point(30, 5),
      new Point(28, 37),
      new Point(100, 2),
      new Point(124, 58),
    ],
  },
  {
    description: "rectangle with 'transform'",
    styles: "width: 100px; height: 50px; transform: translate(30px) rotate(20deg);",
    test_points_inside: [
      new Point(28, 32),
      new Point(44, -10),
      new Point(133, 22),
      new Point(117, 64),
      new Point(65, 27),
    ],
    test_points_outside: [
      new Point(30, 5),
      new Point(28, 37),
      new Point(100, 2),
      new Point(124, 58),
    ],
  },
  {
    description: "rectangle with 'translate' and 'rotate' and 'scale' and 'transform'",
    styles: "width: 100px; height: 50px; translate: 30px; rotate: 40deg; scale: 2; transform: rotate(-20deg) scale(0.5)",
    test_points_inside: [
      new Point(28, 32),
      new Point(44, -10),
      new Point(133, 22),
      new Point(117, 64),
      new Point(65, 27),
    ],
    test_points_outside: [
      new Point(30, 5),
      new Point(28, 37),
      new Point(100, 2),
      new Point(124, 58),
    ],
  },
  {
    description: "square with 'rotate'",
    styles: "width: 10px; height: 10px; rotate: 90deg; transform-origin: 0 10px",
    test_points_inside: [
      new Point(1, 11),
      new Point(9, 11),
      new Point(1, 19),
      new Point(9, 19),
    ],
    test_points_outside: [
      new Point(1, 9),
      new Point(9, 9),
    ],
  },
  {
    description: "square with 'scale'",
    styles: "width: 10px; height: 10px; scale: 0.2;",
    test_points_inside: [
      new Point(4, 4),
      new Point(5, 4),
      new Point(4, 5),
      new Point(5, 5),
    ],
    test_points_outside: [
      new Point(3, 3),
      new Point(3, 5),
      new Point(3, 6),
      new Point(5, 3),
      new Point(5, 6),
      new Point(6, 3),
      new Point(6, 5),
      new Point(6, 6),
    ],
  },
];

for (let t of simple_tests) {
  test(function() {
    let e = document.createElement("div");
    e.setAttribute("style", t.styles);
    document.body.appendChild(e);

    for (let p of t.test_points_inside) {
      let res = document.elementFromPoint(p.x + body_x_margin,
                                          p.y + body_y_margin);
      assert_equals(res, e,
                    `point (${p.x}, ${p.y}) is inside element`);
    }

    for (let p of t.test_points_outside) {
      let res = document.elementFromPoint(p.x + body_x_margin,
                                          p.y + body_y_margin);
      assert_equals(res, document.body,
                    `point (${p.x}, ${p.y}) is outside element`);
    }

    e.remove();
  }, `hit testing of ${t.description}`);
}
</script>
