/* Any copyright is dedicated to the Public Domain.
 * http://creativecommons.org/publicdomain/zero/1.0/ */

// Tests that scrollIntoViewIfNeeded works properly.
const LayoutHelpers = require("devtools/toolkit/layout-helpers");


const TEST_URI = TEST_URI_ROOT + "browser_layoutHelpers.html";

add_task(function*() {
  let [host, win, doc] = yield createHost("bottom", TEST_URI);
  runTest(win);
  host.destroy();
});

function runTest(win) {
  let lh = new LayoutHelpers(win);
  let some = win.document.getElementById('some');

  some.style.top = win.innerHeight + 'px';
  some.style.left = win.innerWidth + 'px';
  // The tests start with a black 2x2 pixels square below bottom right.
  // Do not resize the window during the tests.

  let xPos = Math.floor(win.innerWidth / 2);
  win.scroll(xPos, win.innerHeight + 2);  // Above the viewport.
  lh.scrollIntoViewIfNeeded(some);
  is(win.scrollY, Math.floor(win.innerHeight / 2) + 1,
     'Element completely hidden above should appear centered.');
  is(win.scrollX, xPos,
     'scrollX position has not changed.');

  win.scroll(win.innerWidth / 2, win.innerHeight + 1);  // On the top edge.
  lh.scrollIntoViewIfNeeded(some);
  is(win.scrollY, win.innerHeight,
     'Element partially visible above should appear above.');
  is(win.scrollX, xPos,
     'scrollX position has not changed.');

  win.scroll(win.innerWidth / 2, 0);  // Just below the viewport.
  lh.scrollIntoViewIfNeeded(some);
  is(win.scrollY, Math.floor(win.innerHeight / 2) + 1,
     'Element completely hidden below should appear centered.');
  is(win.scrollX, xPos,
     'scrollX position has not changed.');

  win.scroll(win.innerWidth / 2, 1);  // On the bottom edge.
  lh.scrollIntoViewIfNeeded(some);
  is(win.scrollY, 2,
     'Element partially visible below should appear below.');
  is(win.scrollX, xPos,
     'scrollX position has not changed.');

  win.scroll(win.innerWidth / 2, win.innerHeight + 2);  // Above the viewport.
  lh.scrollIntoViewIfNeeded(some, false);
  is(win.scrollY, win.innerHeight,
     'Element completely hidden above should appear above ' +
     'if parameter is false.');
  is(win.scrollX, xPos,
     'scrollX position has not changed.');

  win.scroll(win.innerWidth / 2, win.innerHeight + 1);  // On the top edge.
  lh.scrollIntoViewIfNeeded(some, false);
  is(win.scrollY, win.innerHeight,
     'Element partially visible above should appear above ' +
     'if parameter is false.');
  is(win.scrollX, xPos,
     'scrollX position has not changed.');

  win.scroll(win.innerWidth / 2, 0);  // Below the viewport.
  lh.scrollIntoViewIfNeeded(some, false);
  is(win.scrollY, 2,
     'Element completely hidden below should appear below ' +
     'if parameter is false.');
  is(win.scrollX, xPos,
     'scrollX position has not changed.');

  win.scroll(win.innerWidth / 2, 1);  // On the bottom edge.
  lh.scrollIntoViewIfNeeded(some, false);
  is(win.scrollY, 2,
     'Element partially visible below should appear below ' +
     'if parameter is false.');
  is(win.scrollX, xPos,
     'scrollX position has not changed.');
}