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Copyright (C) 2017 The Android Open Source Project

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<meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
<meta charset="utf-8">
<title>gr-fixed-panel</title>

<script src="/node_modules/@webcomponents/webcomponentsjs/custom-elements-es5-adapter.js"></script>

<script src="/node_modules/@webcomponents/webcomponentsjs/webcomponents-lite.js"></script>
<script src="/components/wct-browser-legacy/browser.js"></script>
<style>
  /* Prevent horizontal scrolling on page.
   New version of web-component-tester creates body with margins */
  body {
    margin: 0px;
    padding: 0px;
  }
</style>

<test-fixture id="basic">
  <template>
    <gr-fixed-panel>
      <div style="height: 100px"></div>
    </gr-fixed-panel>
  </template>
</test-fixture>

<script type="module">
import '../../../test/common-test-setup.js';
import './gr-fixed-panel.js';
suite('gr-fixed-panel', () => {
  let element;
  let sandbox;

  setup(() => {
    sandbox = sinon.sandbox.create();
    element = fixture('basic');
    element.readyForMeasure = true;
  });

  teardown(() => {
    sandbox.restore();
  });

  test('can be disabled with floatingDisabled', () => {
    element.floatingDisabled = true;
    sandbox.stub(element, '_reposition');
    window.dispatchEvent(new CustomEvent('resize'));
    element.flushDebouncer('update');
    assert.isFalse(element._reposition.called);
  });

  test('header is the height of the content', () => {
    assert.equal(element.getBoundingClientRect().height, 100);
  });

  test('scroll triggers _reposition', () => {
    sandbox.stub(element, '_reposition');
    window.dispatchEvent(new CustomEvent('scroll'));
    element.flushDebouncer('update');
    assert.isTrue(element._reposition.called);
  });

  suite('_reposition', () => {
    const getHeaderTop = function() {
      return element.$.header.style.top;
    };

    const emulateScrollY = function(distance) {
      element._getElementTop.returns(element._headerTopInitial - distance);
      element._updateDebounced();
      element.flushDebouncer('scroll');
    };

    setup(() => {
      element._headerTopInitial = 10;
      sandbox.stub(element, '_getElementTop')
          .returns(element._headerTopInitial);
    });

    test('scrolls header along with document', () => {
      emulateScrollY(20);
      // No top property is set when !_headerFloating.
      assert.equal(getHeaderTop(), '');
    });

    test('does not stick to the top by default', () => {
      emulateScrollY(150);
      // No top property is set when !_headerFloating.
      assert.equal(getHeaderTop(), '');
    });

    test('sticks to the top if enabled', () => {
      element.keepOnScroll = true;
      emulateScrollY(120);
      assert.equal(getHeaderTop(), '0px');
    });

    test('drops a shadow when fixed to the top', () => {
      element.keepOnScroll = true;
      emulateScrollY(5);
      assert.isFalse(element.$.header.classList.contains('fixedAtTop'));
      emulateScrollY(120);
      assert.isTrue(element.$.header.classList.contains('fixedAtTop'));
    });
  });
});
</script>