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/* 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/. */

const triggeringPrincipal_base64 = E10SUtils.SERIALIZED_SYSTEMPRINCIPAL;

const TAB_STATE_NEEDS_RESTORE = 1;
const TAB_STATE_RESTORING = 2;

const ROOT = getRootDirectory(gTestPath);
const HTTPROOT = ROOT.replace(
  "chrome://mochitests/content/",
  "http://example.com/"
);
const HTTPSROOT = ROOT.replace(
  "chrome://mochitests/content/",
  "https://example.com/"
);

const { SessionSaver } = ChromeUtils.importESModule(
  "resource:///modules/sessionstore/SessionSaver.sys.mjs"
);
const { SessionFile } = ChromeUtils.importESModule(
  "resource:///modules/sessionstore/SessionFile.sys.mjs"
);
const { TabState } = ChromeUtils.importESModule(
  "resource:///modules/sessionstore/TabState.sys.mjs"
);
const { TabStateFlusher } = ChromeUtils.importESModule(
  "resource:///modules/sessionstore/TabStateFlusher.sys.mjs"
);
const ss = SessionStore;

// Some tests here assume that all restored tabs are loaded without waiting for
// the user to bring them to the foreground. We ensure this by resetting the
// related preference (see the "firefox.js" defaults file for details).
Services.prefs.setBoolPref("browser.sessionstore.restore_on_demand", false);
registerCleanupFunction(function () {
  Services.prefs.clearUserPref("browser.sessionstore.restore_on_demand");
});

// Obtain access to internals
Services.prefs.setBoolPref("browser.sessionstore.debug", true);
registerCleanupFunction(function () {
  Services.prefs.clearUserPref("browser.sessionstore.debug");
});

// This kicks off the search service used on about:home and allows the
// session restore tests to be run standalone without triggering errors.
Cc["@mozilla.org/browser/clh;1"].getService(Ci.nsIBrowserHandler).defaultArgs;

function provideWindow(aCallback, aURL, aFeatures) {
  function callbackSoon(aWindow) {
    executeSoon(function executeCallbackSoon() {
      aCallback(aWindow);
    });
  }

  let win = openDialog(
    AppConstants.BROWSER_CHROME_URL,
    "",
    aFeatures || "chrome,all,dialog=no",
    aURL || "about:blank"
  );
  whenWindowLoaded(win, function onWindowLoaded(aWin) {
    if (!aURL) {
      info("Loaded a blank window.");
      callbackSoon(aWin);
      return;
    }

    aWin.gBrowser.selectedBrowser.addEventListener(
      "load",
      function () {
        callbackSoon(aWin);
      },
      { capture: true, once: true }
    );
  });
}

// This assumes that tests will at least have some state/entries
function waitForBrowserState(aState, aSetStateCallback) {
  if (typeof aState == "string") {
    aState = JSON.parse(aState);
  }
  if (typeof aState != "object") {
    throw new TypeError(
      "Argument must be an object or a JSON representation of an object"
    );
  }
  let windows = [window];
  let tabsRestored = 0;
  let expectedTabsRestored = 0;
  let expectedWindows = aState.windows.length;
  let windowsOpen = 1;
  let listening = false;
  let windowObserving = false;
  let restoreHiddenTabs = Services.prefs.getBoolPref(
    "browser.sessionstore.restore_hidden_tabs"
  );
  // This should match the |restoreTabsLazily| value that
  // SessionStore.restoreWindow() uses.
  let restoreTabsLazily =
    Services.prefs.getBoolPref("browser.sessionstore.restore_on_demand") &&
    Services.prefs.getBoolPref("browser.sessionstore.restore_tabs_lazily");

  aState.windows.forEach(function (winState) {
    winState.tabs.forEach(function (tabState) {
      if (!restoreTabsLazily && (restoreHiddenTabs || !tabState.hidden)) {
        expectedTabsRestored++;
      }
    });
  });

  // If there are only hidden tabs and restoreHiddenTabs = false, we still
  // expect one of them to be restored because it gets shown automatically.
  // Otherwise if lazy tab restore there will only be one tab restored per window.
  if (!expectedTabsRestored) {
    expectedTabsRestored = 1;
  } else if (restoreTabsLazily) {
    expectedTabsRestored = aState.windows.length;
  }

  function onSSTabRestored(aEvent) {
    if (++tabsRestored == expectedTabsRestored) {
      // Remove the event listener from each window
      windows.forEach(function (win) {
        win.gBrowser.tabContainer.removeEventListener(
          "SSTabRestored",
          onSSTabRestored,
          true
        );
      });
      listening = false;
      info("running " + aSetStateCallback.name);
      executeSoon(aSetStateCallback);
    }
  }

  // Used to add our listener to further windows so we can catch SSTabRestored
  // coming from them when creating a multi-window state.
  function windowObserver(aSubject, aTopic, aData) {
    if (aTopic == "domwindowopened") {
      let newWindow = aSubject;
      newWindow.addEventListener(
        "load",
        function () {
          if (++windowsOpen == expectedWindows) {
            Services.ww.unregisterNotification(windowObserver);
            windowObserving = false;
          }

          // Track this window so we can remove the progress listener later
          windows.push(newWindow);
          // Add the progress listener
          newWindow.gBrowser.tabContainer.addEventListener(
            "SSTabRestored",
            onSSTabRestored,
            true
          );
        },
        { once: true }
      );
    }
  }

  // We only want to register the notification if we expect more than 1 window
  if (expectedWindows > 1) {
    registerCleanupFunction(function () {
      if (windowObserving) {
        Services.ww.unregisterNotification(windowObserver);
      }
    });
    windowObserving = true;
    Services.ww.registerNotification(windowObserver);
  }

  registerCleanupFunction(function () {
    if (listening) {
      windows.forEach(function (win) {
        win.gBrowser.tabContainer.removeEventListener(
          "SSTabRestored",
          onSSTabRestored,
          true
        );
      });
    }
  });
  // Add the event listener for this window as well.
  listening = true;
  gBrowser.tabContainer.addEventListener(
    "SSTabRestored",
    onSSTabRestored,
    true
  );

  // Ensure setBrowserState() doesn't remove the initial tab.
  gBrowser.selectedTab = gBrowser.tabs[0];

  // Finally, call setBrowserState
  ss.setBrowserState(JSON.stringify(aState));
}

function promiseBrowserState(aState) {
  return new Promise(resolve => waitForBrowserState(aState, resolve));
}

function promiseTabState(tab, state) {
  if (typeof state != "string") {
    state = JSON.stringify(state);
  }

  let promise = promiseTabRestored(tab);
  ss.setTabState(tab, state);
  return promise;
}

function promiseWindowRestoring(win) {
  return new Promise(resolve =>
    win.addEventListener("SSWindowRestoring", resolve, { once: true })
  );
}

function promiseWindowRestored(win) {
  return new Promise(resolve =>
    win.addEventListener("SSWindowRestored", resolve, { once: true })
  );
}

async function setBrowserState(state, win = window) {
  ss.setBrowserState(typeof state != "string" ? JSON.stringify(state) : state);
  await promiseWindowRestored(win);
}

async function setWindowState(win, state, overwrite = false) {
  ss.setWindowState(
    win,
    typeof state != "string" ? JSON.stringify(state) : state,
    overwrite
  );
  await promiseWindowRestored(win);
}

function waitForTopic(aTopic, aTimeout, aCallback) {
  let observing = false;
  function removeObserver() {
    if (!observing) {
      return;
    }
    Services.obs.removeObserver(observer, aTopic);
    observing = false;
  }

  let timeout = setTimeout(function () {
    removeObserver();
    aCallback(false);
  }, aTimeout);

  function observer(subject, topic, data) {
    removeObserver();
    timeout = clearTimeout(timeout);
    executeSoon(() => aCallback(true));
  }

  registerCleanupFunction(function () {
    removeObserver();
    if (timeout) {
      clearTimeout(timeout);
    }
  });

  observing = true;
  Services.obs.addObserver(observer, aTopic);
}

/**
 * Wait until session restore has finished collecting its data and is
 * has written that data ("sessionstore-state-write-complete").
 *
 * @param {function} aCallback If sessionstore-state-write-complete is sent
 * within buffering interval + 100 ms, the callback is passed |true|,
 * otherwise, it is passed |false|.
 */
function waitForSaveState(aCallback) {
  let timeout =
    100 + Services.prefs.getIntPref("browser.sessionstore.interval");
  return waitForTopic("sessionstore-state-write-complete", timeout, aCallback);
}
function promiseSaveState() {
  return new Promise((resolve, reject) => {
    waitForSaveState(isSuccessful => {
      if (!isSuccessful) {
        reject(new Error("Save state timeout"));
      } else {
        resolve();
      }
    });
  });
}
function forceSaveState() {
  return SessionSaver.run();
}

function promiseRecoveryFileContents() {
  let promise = forceSaveState();
  return promise.then(function () {
    return IOUtils.readUTF8(SessionFile.Paths.recovery, {
      decompress: true,
    });
  });
}

var promiseForEachSessionRestoreFile = async function (cb) {
  for (let key of SessionFile.Paths.loadOrder) {
    let data = "";
    try {
      data = await IOUtils.readUTF8(SessionFile.Paths[key], {
        decompress: true,
      });
    } catch (ex) {
      // Ignore missing files
      if (!(DOMException.isInstance(ex) && ex.name == "NotFoundError")) {
        throw ex;
      }
    }
    cb(data, key);
  }
};

function promiseBrowserLoaded(
  aBrowser,
  ignoreSubFrames = true,
  wantLoad = null
) {
  return BrowserTestUtils.browserLoaded(aBrowser, !ignoreSubFrames, wantLoad);
}

function whenWindowLoaded(aWindow, aCallback) {
  aWindow.addEventListener(
    "load",
    function () {
      executeSoon(function executeWhenWindowLoaded() {
        aCallback(aWindow);
      });
    },
    { once: true }
  );
}
function promiseWindowLoaded(aWindow) {
  return new Promise(resolve => whenWindowLoaded(aWindow, resolve));
}

var gUniqueCounter = 0;
function r() {
  return Date.now() + "-" + ++gUniqueCounter;
}

function* BrowserWindowIterator() {
  for (let currentWindow of Services.wm.getEnumerator("navigator:browser")) {
    if (!currentWindow.closed) {
      yield currentWindow;
    }
  }
}

var gWebProgressListener = {
  _callback: null,

  setCallback(aCallback) {
    if (!this._callback) {
      window.gBrowser.addTabsProgressListener(this);
    }
    this._callback = aCallback;
  },

  unsetCallback() {
    if (this._callback) {
      this._callback = null;
      window.gBrowser.removeTabsProgressListener(this);
    }
  },

  onStateChange(aBrowser, aWebProgress, aRequest, aStateFlags, aStatus) {
    if (
      aStateFlags & Ci.nsIWebProgressListener.STATE_STOP &&
      aStateFlags & Ci.nsIWebProgressListener.STATE_IS_NETWORK &&
      aStateFlags & Ci.nsIWebProgressListener.STATE_IS_WINDOW
    ) {
      this._callback(aBrowser);
    }
  },
};

registerCleanupFunction(function () {
  gWebProgressListener.unsetCallback();
});

var gProgressListener = {
  _callback: null,

  setCallback(callback) {
    Services.obs.addObserver(this, "sessionstore-debug-tab-restored");
    this._callback = callback;
  },

  unsetCallback() {
    if (this._callback) {
      this._callback = null;
      Services.obs.removeObserver(this, "sessionstore-debug-tab-restored");
    }
  },

  observe(browser, topic, data) {
    gProgressListener.onRestored(browser);
  },

  onRestored(browser) {
    if (ss.getInternalObjectState(browser) == TAB_STATE_RESTORING) {
      let args = [browser].concat(gProgressListener._countTabs());
      gProgressListener._callback.apply(gProgressListener, args);
    }
  },

  _countTabs() {
    let needsRestore = 0,
      isRestoring = 0,
      wasRestored = 0;

    for (let win of BrowserWindowIterator()) {
      for (let i = 0; i < win.gBrowser.tabs.length; i++) {
        let browser = win.gBrowser.tabs[i].linkedBrowser;
        let state = ss.getInternalObjectState(browser);
        if (browser.isConnected && !state) {
          wasRestored++;
        } else if (state == TAB_STATE_RESTORING) {
          isRestoring++;
        } else if (state == TAB_STATE_NEEDS_RESTORE || !browser.isConnected) {
          needsRestore++;
        }
      }
    }
    return [needsRestore, isRestoring, wasRestored];
  },
};

registerCleanupFunction(function () {
  gProgressListener.unsetCallback();
});

// Close all but our primary window.
function promiseAllButPrimaryWindowClosed() {
  let windows = [];
  for (let win of BrowserWindowIterator()) {
    if (win != window) {
      windows.push(win);
    }
  }

  return Promise.all(windows.map(BrowserTestUtils.closeWindow));
}

// Forget all closed windows.
function forgetClosedWindows() {
  while (ss.getClosedWindowCount() > 0) {
    ss.forgetClosedWindow(0);
  }
}

// Forget all closed tabs for a window
function forgetClosedTabs(win) {
  while (ss.getClosedTabCountForWindow(win) > 0) {
    ss.forgetClosedTab(win, 0);
  }
}

/**
 * When opening a new window it is not sufficient to wait for its load event.
 * We need to use whenDelayedStartupFinshed() here as the browser window's
 * delayedStartup() routine is executed one tick after the window's load event
 * has been dispatched. browser-delayed-startup-finished might be deferred even
 * further if parts of the window's initialization process take more time than
 * expected (e.g. reading a big session state from disk).
 */
function whenNewWindowLoaded(aOptions, aCallback) {
  let features = "";
  let url = "about:blank";

  if ((aOptions && aOptions.private) || false) {
    features = ",private";
    url = "about:privatebrowsing";
  }

  let win = openDialog(
    AppConstants.BROWSER_CHROME_URL,
    "",
    "chrome,all,dialog=no" + features,
    url
  );
  let delayedStartup = promiseDelayedStartupFinished(win);

  let browserLoaded = new Promise(resolve => {
    if (url == "about:blank") {
      resolve();
      return;
    }

    win.addEventListener(
      "load",
      function () {
        let browser = win.gBrowser.selectedBrowser;
        promiseBrowserLoaded(browser).then(resolve);
      },
      { once: true }
    );
  });

  Promise.all([delayedStartup, browserLoaded]).then(() => aCallback(win));
}
function promiseNewWindowLoaded(aOptions) {
  return new Promise(resolve => whenNewWindowLoaded(aOptions, resolve));
}

/**
 * This waits for the browser-delayed-startup-finished notification of a given
 * window. It indicates that the windows has loaded completely and is ready to
 * be used for testing.
 */
function whenDelayedStartupFinished(aWindow, aCallback) {
  Services.obs.addObserver(function observer(aSubject, aTopic) {
    if (aWindow == aSubject) {
      Services.obs.removeObserver(observer, aTopic);
      executeSoon(aCallback);
    }
  }, "browser-delayed-startup-finished");
}
function promiseDelayedStartupFinished(aWindow) {
  return new Promise(resolve => whenDelayedStartupFinished(aWindow, resolve));
}

function promiseTabRestored(tab) {
  return BrowserTestUtils.waitForEvent(tab, "SSTabRestored");
}

function promiseTabRestoring(tab) {
  return BrowserTestUtils.waitForEvent(tab, "SSTabRestoring");
}

// Removes the given tab immediately and returns a promise that resolves when
// all pending status updates (messages) of the closing tab have been received.
function promiseRemoveTabAndSessionState(tab) {
  let sessionUpdatePromise = BrowserTestUtils.waitForSessionStoreUpdate(tab);
  BrowserTestUtils.removeTab(tab);
  return sessionUpdatePromise;
}

// Write DOMSessionStorage data to the given browser.
function modifySessionStorage(browser, storageData, storageOptions = {}) {
  let browsingContext = browser.browsingContext;
  if (storageOptions && "frameIndex" in storageOptions) {
    browsingContext = browsingContext.children[storageOptions.frameIndex];
  }

  return SpecialPowers.spawn(
    browsingContext,
    [[storageData, storageOptions]],
    async function ([data, options]) {
      let frame = content;
      let keys = new Set(Object.keys(data));
      let isClearing = !keys.size;
      let storage = frame.sessionStorage;

      return new Promise(resolve => {
        docShell.chromeEventHandler.addEventListener(
          "MozSessionStorageChanged",
          function onStorageChanged(event) {
            if (event.storageArea == storage) {
              keys.delete(event.key);
            }

            if (keys.size == 0) {
              docShell.chromeEventHandler.removeEventListener(
                "MozSessionStorageChanged",
                onStorageChanged,
                true
              );
              resolve();
            }
          },
          true
        );

        if (isClearing) {
          storage.clear();
        } else {
          for (let key of keys) {
            frame.sessionStorage[key] = data[key];
          }
        }
      });
    }
  );
}

function pushPrefs(...aPrefs) {
  return SpecialPowers.pushPrefEnv({ set: aPrefs });
}

function popPrefs() {
  return SpecialPowers.popPrefEnv();
}

function setScrollPosition(bc, x, y) {
  return SpecialPowers.spawn(bc, [x, y], (childX, childY) => {
    return new Promise(resolve => {
      content.addEventListener(
        "mozvisualscroll",
        function onScroll(event) {
          if (content.document.ownerGlobal.visualViewport == event.target) {
            content.removeEventListener("mozvisualscroll", onScroll, {
              mozSystemGroup: true,
            });
            resolve();
          }
        },
        { mozSystemGroup: true }
      );
      content.scrollTo(childX, childY);
    });
  });
}

async function checkScroll(tab, expected, msg) {
  let browser = tab.linkedBrowser;
  await TabStateFlusher.flush(browser);

  let scroll = JSON.parse(ss.getTabState(tab)).scroll || null;
  is(JSON.stringify(scroll), JSON.stringify(expected), msg);
}

function whenDomWindowClosedHandled(aCallback) {
  Services.obs.addObserver(function observer(aSubject, aTopic) {
    Services.obs.removeObserver(observer, aTopic);
    aCallback();
  }, "sessionstore-debug-domwindowclosed-handled");
}

function getPropertyOfFormField(browserContext, selector, propName) {
  return SpecialPowers.spawn(
    browserContext,
    [selector, propName],
    (selectorChild, propNameChild) => {
      return content.document.querySelector(selectorChild)[propNameChild];
    }
  );
}

function setPropertyOfFormField(browserContext, selector, propName, newValue) {
  return SpecialPowers.spawn(
    browserContext,
    [selector, propName, newValue],
    (selectorChild, propNameChild, newValueChild) => {
      let node = content.document.querySelector(selectorChild);
      node[propNameChild] = newValueChild;

      let event = node.ownerDocument.createEvent("UIEvents");
      event.initUIEvent("input", true, true, node.ownerGlobal, 0);
      node.dispatchEvent(event);
    }
  );
}

function promiseOnHistoryReplaceEntry(browser) {
  if (SpecialPowers.Services.appinfo.sessionHistoryInParent) {
    return new Promise(resolve => {
      let sessionHistory = browser.browsingContext?.sessionHistory;
      if (sessionHistory) {
        var historyListener = {
          OnHistoryNewEntry() {},
          OnHistoryGotoIndex() {},
          OnHistoryPurge() {},
          OnHistoryReload() {
            return true;
          },

          OnHistoryReplaceEntry() {
            resolve();
          },

          QueryInterface: ChromeUtils.generateQI([
            "nsISHistoryListener",
            "nsISupportsWeakReference",
          ]),
        };

        sessionHistory.addSHistoryListener(historyListener);
      }
    });
  }

  return SpecialPowers.spawn(browser, [], () => {
    return new Promise(resolve => {
      var historyListener = {
        OnHistoryNewEntry() {},
        OnHistoryGotoIndex() {},
        OnHistoryPurge() {},
        OnHistoryReload() {
          return true;
        },

        OnHistoryReplaceEntry() {
          resolve();
        },

        QueryInterface: ChromeUtils.generateQI([
          "nsISHistoryListener",
          "nsISupportsWeakReference",
        ]),
      };

      var { sessionHistory } = this.docShell.QueryInterface(
        Ci.nsIWebNavigation
      );
      if (sessionHistory) {
        sessionHistory.legacySHistory.addSHistoryListener(historyListener);
      }
    });
  });
}

function loadTestSubscript(filePath) {
  Services.scriptloader.loadSubScript(new URL(filePath, gTestPath).href, this);
}

function addCoopTask(aFile, aTest, aUrlRoot) {
  async function taskToBeAdded() {
    info(`File ${aFile} has COOP headers enabled`);
    let filePath = `browser/browser/components/sessionstore/test/${aFile}`;
    let url = aUrlRoot + `coopHeaderCommon.sjs?fileRoot=${filePath}`;
    await aTest(url);
  }
  Object.defineProperty(taskToBeAdded, "name", { value: aTest.name });
  add_task(taskToBeAdded);
}

function addNonCoopTask(aFile, aTest, aUrlRoot) {
  async function taskToBeAdded() {
    await aTest(aUrlRoot + aFile);
  }
  Object.defineProperty(taskToBeAdded, "name", { value: aTest.name });
  add_task(taskToBeAdded);
}

async function openAndCloseTab(window, url) {
  let tab = BrowserTestUtils.addTab(window.gBrowser, url);
  await promiseBrowserLoaded(tab.linkedBrowser, true, url);
  await TabStateFlusher.flush(tab.linkedBrowser);
  await promiseRemoveTabAndSessionState(tab);
}

/**
 * This is regrettable, but when `promiseBrowserState` resolves, we're still
 * midway through loading the tabs. To avoid race conditions in URLs for tabs
 * being available, wait for all the loads to finish:
 */
function promiseSessionStoreLoads(numberOfLoads) {
  let loadsSeen = 0;
  return new Promise(resolve => {
    Services.obs.addObserver(function obs(browser) {
      loadsSeen++;
      if (loadsSeen == numberOfLoads) {
        resolve();
      }
      // The typeof check is here to avoid one test messing with everything else by
      // keeping the observer indefinitely.
      if (typeof info == "undefined" || loadsSeen >= numberOfLoads) {
        Services.obs.removeObserver(obs, "sessionstore-debug-tab-restored");
      }
      info("Saw load for " + browser.currentURI.spec);
    }, "sessionstore-debug-tab-restored");
  });
}