/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

let { ForgetAboutSite } = ChromeUtils.importESModule(
  "resource://gre/modules/ForgetAboutSite.sys.mjs"
);

function promiseClearHistory() {
  return new Promise(resolve => {
    let observer = {
      observe(aSubject, aTopic, aData) {
        Services.obs.removeObserver(
          this,
          "browser:purge-session-history-for-domain"
        );
        resolve();
      },
    };
    Services.obs.addObserver(
      observer,
      "browser:purge-session-history-for-domain"
    );
  });
}

add_task(async function () {
  // utility functions
  function countClosedTabsByTitle(aClosedTabList, aTitle) {
    return aClosedTabList.filter(aData => aData.title == aTitle).length;
  }

  function countOpenTabsByTitle(aOpenTabList, aTitle) {
    return aOpenTabList.filter(aData =>
      aData.entries.some(aEntry => aEntry.title == aTitle)
    ).length;
  }

  // backup old state
  let oldState = ss.getBrowserState();
  let oldState_wins = JSON.parse(oldState).windows.length;
  if (oldState_wins != 1) {
    ok(
      false,
      "oldState in test_purge has " + oldState_wins + " windows instead of 1"
    );
  }

  // create a new state for testing
  const REMEMBER = Date.now(),
    FORGET = Math.random();
  let testState = {
    windows: [
      {
        tabs: [
          {
            entries: [
              { url: "http://example.com/", triggeringPrincipal_base64 },
            ],
          },
        ],
        selected: 1,
      },
    ],
    _closedWindows: [
      // _closedWindows[0]
      {
        tabs: [
          {
            entries: [
              {
                url: "http://example.com/",
                triggeringPrincipal_base64,
                title: REMEMBER,
              },
            ],
          },
          {
            entries: [
              {
                url: "http://mozilla.org/",
                triggeringPrincipal_base64,
                title: FORGET,
              },
            ],
          },
        ],
        selected: 2,
        title: "mozilla.org",
        _closedTabs: [],
      },
      // _closedWindows[1]
      {
        tabs: [
          {
            entries: [
              {
                url: "http://mozilla.org/",
                triggeringPrincipal_base64,
                title: FORGET,
              },
            ],
          },
          {
            entries: [
              {
                url: "http://example.com/",
                triggeringPrincipal_base64,
                title: REMEMBER,
              },
            ],
          },
          {
            entries: [
              {
                url: "http://example.com/",
                triggeringPrincipal_base64,
                title: REMEMBER,
              },
            ],
          },
          {
            entries: [
              {
                url: "http://mozilla.org/",
                triggeringPrincipal_base64,
                title: FORGET,
              },
            ],
          },
          {
            entries: [
              {
                url: "http://example.com/",
                triggeringPrincipal_base64,
                title: REMEMBER,
              },
            ],
          },
        ],
        selected: 5,
        _closedTabs: [],
      },
      // _closedWindows[2]
      {
        tabs: [
          {
            entries: [
              {
                url: "http://example.com/",
                triggeringPrincipal_base64,
                title: REMEMBER,
              },
            ],
          },
        ],
        selected: 1,
        _closedTabs: [
          {
            state: {
              entries: [
                {
                  url: "http://mozilla.org/",
                  triggeringPrincipal_base64,
                  title: FORGET,
                },
                {
                  url: "http://mozilla.org/again",
                  triggeringPrincipal_base64,
                  title: "doesn't matter",
                },
              ],
            },
            pos: 1,
            title: FORGET,
          },
          {
            state: {
              entries: [
                {
                  url: "http://example.com",
                  triggeringPrincipal_base64,
                  title: REMEMBER,
                },
              ],
            },
            title: REMEMBER,
          },
        ],
      },
    ],
  };

  // set browser to test state
  ss.setBrowserState(JSON.stringify(testState));

  // purge domain & check that we purged correctly for closed windows
  let clearHistoryPromise = promiseClearHistory();
  await ForgetAboutSite.removeDataFromDomain("mozilla.org");
  await clearHistoryPromise;

  let closedWindowData = ss.getClosedWindowData();

  // First set of tests for _closedWindows[0] - tests basics
  let win = closedWindowData[0];
  is(win.tabs.length, 1, "1 tab was removed");
  is(countOpenTabsByTitle(win.tabs, FORGET), 0, "The correct tab was removed");
  is(
    countOpenTabsByTitle(win.tabs, REMEMBER),
    1,
    "The correct tab was remembered"
  );
  is(win.selected, 1, "Selected tab has changed");
  is(win.title, REMEMBER, "The window title was correctly updated");

  // Test more complicated case
  win = closedWindowData[1];
  is(win.tabs.length, 3, "2 tabs were removed");
  is(
    countOpenTabsByTitle(win.tabs, FORGET),
    0,
    "The correct tabs were removed"
  );
  is(
    countOpenTabsByTitle(win.tabs, REMEMBER),
    3,
    "The correct tabs were remembered"
  );
  is(win.selected, 3, "Selected tab has changed");
  is(win.title, REMEMBER, "The window title was correctly updated");

  // Tests handling of _closedTabs
  win = closedWindowData[2];
  is(
    countClosedTabsByTitle(win._closedTabs, REMEMBER),
    1,
    "The correct number of tabs were removed, and the correct ones"
  );
  is(
    countClosedTabsByTitle(win._closedTabs, FORGET),
    0,
    "All tabs to be forgotten were indeed removed"
  );

  // restore pre-test state
  ss.setBrowserState(oldState);
});