/* 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/. */

function test() {
  /** Test for Bug 447951 **/

  waitForExplicitFinish();
  const baseURL = "http://mochi.test:8888/browser/" +
    "browser/components/sessionstore/test/browser_447951_sample.html#";

  // Make sure the functionality added in bug 943339 doesn't affect the results
  gPrefService.setIntPref("browser.sessionstore.max_serialize_back", -1);
  gPrefService.setIntPref("browser.sessionstore.max_serialize_forward", -1);
  registerCleanupFunction(function () {
    gPrefService.clearUserPref("browser.sessionstore.max_serialize_back");
    gPrefService.clearUserPref("browser.sessionstore.max_serialize_forward");
  });

  let tab = gBrowser.addTab();
  promiseBrowserLoaded(tab.linkedBrowser).then(() => {
    let tabState = { entries: [] };
    let max_entries = gPrefService.getIntPref("browser.sessionhistory.max_entries");
    for (let i = 0; i < max_entries; i++)
      tabState.entries.push({ url: baseURL + i });

    promiseTabState(tab, tabState).then(() => {
      return TabStateFlusher.flush(tab.linkedBrowser);
    }).then(() => {
      tabState = JSON.parse(ss.getTabState(tab));
      is(tabState.entries.length, max_entries, "session history filled to the limit");
      is(tabState.entries[0].url, baseURL + 0, "... but not more");

      // visit yet another anchor (appending it to session history)
      ContentTask.spawn(tab.linkedBrowser, null, function() {
        content.window.document.querySelector("a").click();
      }).then(flushAndCheck);

      function flushAndCheck() {
        TabStateFlusher.flush(tab.linkedBrowser).then(check);
      }

      function check() {
        tabState = JSON.parse(ss.getTabState(tab));
        if (tab.linkedBrowser.currentURI.spec != baseURL + "end") {
          // It may take a few passes through the event loop before we
          // get the right URL.
          executeSoon(flushAndCheck);
          return;
        }

        is(tab.linkedBrowser.currentURI.spec, baseURL + "end",
           "the new anchor was loaded");
        is(tabState.entries[tabState.entries.length - 1].url, baseURL + "end",
           "... and ignored");
        is(tabState.entries[0].url, baseURL + 1,
           "... and the first item was removed");

        // clean up
        gBrowser.removeTab(tab);
        finish();
      }
    });
  });
}
