1 files changed, 414 insertions, 0 deletions
diff --git a/remote/shared/NavigationManager.sys.mjs b/remote/shared/NavigationManager.sys.mjs
new file mode 100644
index 0000000000..1f19ef3c0d
--- /dev/null
+++ b/remote/shared/NavigationManager.sys.mjs
@@ -0,0 +1,414 @@
+/* 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/. */
+
+import { EventEmitter } from "resource://gre/modules/EventEmitter.sys.mjs";
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  generateUUID: "chrome://remote/content/shared/UUID.sys.mjs",
+  Log: "chrome://remote/content/shared/Log.sys.mjs",
+  registerNavigationListenerActor:
+    "chrome://remote/content/shared/js-window-actors/NavigationListenerActor.sys.mjs",
+  TabManager: "chrome://remote/content/shared/TabManager.sys.mjs",
+  truncate: "chrome://remote/content/shared/Format.sys.mjs",
+  unregisterNavigationListenerActor:
+    "chrome://remote/content/shared/js-window-actors/NavigationListenerActor.sys.mjs",
+});
+
+ChromeUtils.defineLazyGetter(lazy, "logger", () => lazy.Log.get());
+
+/**
+ * @typedef {object} BrowsingContextDetails
+ * @property {string} browsingContextId - The browsing context id.
+ * @property {string} browserId - The id of the Browser owning the browsing
+ *     context.
+ * @property {BrowsingContext=} context - The BrowsingContext itself, if
+ *     available.
+ * @property {boolean} isTopBrowsingContext - Whether the browsing context is
+ *     top level.
+ */
+
+/**
+ * @typedef {object} NavigationInfo
+ * @property {boolean} finished - Whether the navigation is finished or not.
+ * @property {string} navigationId - The UUID for the navigation.
+ * @property {string} navigable - The UUID for the navigable.
+ * @property {string} url - The target url for the navigation.
+ */
+
+/**
+ * The NavigationRegistry is responsible for monitoring all navigations happening
+ * in the browser.
+ *
+ * It relies on a JSWindowActor pair called NavigationListener{Parent|Child},
+ * found under remote/shared/js-window-actors. As a simple overview, the
+ * NavigationListenerChild will monitor navigations in all window globals using
+ * content process WebProgressListener, and will forward each relevant update to
+ * the NavigationListenerParent
+ *
+ * The NavigationRegistry singleton holds the map of navigations, from navigable
+ * to NavigationInfo. It will also be called by NavigationListenerParent
+ * whenever a navigation event happens.
+ *
+ * This singleton is not exported outside of this class, and consumers instead
+ * need to use the NavigationManager class. The NavigationRegistry keeps track
+ * of how many NavigationListener instances are currently listening in order to
+ * know if the NavigationListenerActor should be registered or not.
+ *
+ * The NavigationRegistry exposes an API to retrieve the current or last
+ * navigation for a given navigable, and also forwards events to notify about
+ * navigation updates to individual NavigationManager instances.
+ *
+ * @class NavigationRegistry
+ */
+class NavigationRegistry extends EventEmitter {
+  #managers;
+  #navigations;
+  #navigationIds;
+
+  constructor() {
+    super();
+
+    // Set of NavigationManager instances currently used.
+    this.#managers = new Set();
+
+    // Maps navigable to NavigationInfo.
+    this.#navigations = new WeakMap();
+
+    // Maps navigable id to navigation id. Only used to pre-register navigation
+    // ids before the actual event is detected.
+    this.#navigationIds = new Map();
+  }
+
+  /**
+   * Retrieve the last known navigation data for a given browsing context.
+   *
+   * @param {BrowsingContext} context
+   *     The browsing context for which the navigation event was recorded.
+   * @returns {NavigationInfo|null}
+   *     The last known navigation data, or null.
+   */
+  getNavigationForBrowsingContext(context) {
+    if (!lazy.TabManager.isValidCanonicalBrowsingContext(context)) {
+      // Bail out if the provided context is not a valid CanonicalBrowsingContext
+      // instance.
+      return null;
+    }
+
+    const navigable = lazy.TabManager.getNavigableForBrowsingContext(context);
+    if (!this.#navigations.has(navigable)) {
+      return null;
+    }
+
+    return this.#navigations.get(navigable);
+  }
+
+  /**
+   * Start monitoring navigations in all browsing contexts. This will register
+   * the NavigationListener JSWindowActor and will initialize them in all
+   * existing browsing contexts.
+   */
+  startMonitoring(listener) {
+    if (this.#managers.size == 0) {
+      lazy.registerNavigationListenerActor();
+    }
+
+    this.#managers.add(listener);
+  }
+
+  /**
+   * Stop monitoring navigations. This will unregister the NavigationListener
+   * JSWindowActor and clear the information collected about navigations so far.
+   */
+  stopMonitoring(listener) {
+    if (!this.#managers.has(listener)) {
+      return;
+    }
+
+    this.#managers.delete(listener);
+    if (this.#managers.size == 0) {
+      lazy.unregisterNavigationListenerActor();
+      // Clear the map.
+      this.#navigations = new WeakMap();
+    }
+  }
+
+  /**
+   * Called when a same-document navigation is recorded from the
+   * NavigationListener actors.
+   *
+   * This entry point is only intended to be called from
+   * NavigationListenerParent, to avoid setting up observers or listeners,
+   * which are unnecessary since NavigationManager has to be a singleton.
+   *
+   * @param {object} data
+   * @param {BrowsingContext} data.context
+   *     The browsing context for which the navigation event was recorded.
+   * @param {string} data.url
+   *     The URL as string for the navigation.
+   * @returns {NavigationInfo}
+   *     The navigation created for this same-document navigation.
+   */
+  notifyLocationChanged(data) {
+    const { contextDetails, url } = data;
+
+    const context = this.#getContextFromContextDetails(contextDetails);
+    const navigable = lazy.TabManager.getNavigableForBrowsingContext(context);
+    const navigableId = lazy.TabManager.getIdForBrowsingContext(context);
+
+    const navigationId = this.#getOrCreateNavigationId(navigableId);
+    const navigation = { finished: true, navigationId, url };
+    this.#navigations.set(navigable, navigation);
+
+    // Same document navigations are immediately done, fire a single event.
+    this.emit("location-changed", { navigationId, navigableId, url });
+
+    return navigation;
+  }
+
+  /**
+   * Called when a navigation-started event is recorded from the
+   * NavigationListener actors.
+   *
+   * This entry point is only intended to be called from
+   * NavigationListenerParent, to avoid setting up observers or listeners,
+   * which are unnecessary since NavigationManager has to be a singleton.
+   *
+   * @param {object} data
+   * @param {BrowsingContextDetails} data.contextDetails
+   *     The details about the browsing context for this navigation.
+   * @param {string} data.url
+   *     The URL as string for the navigation.
+   * @returns {NavigationInfo}
+   *     The created navigation or the ongoing navigation, if applicable.
+   */
+  notifyNavigationStarted(data) {
+    const { contextDetails, url } = data;
+
+    const context = this.#getContextFromContextDetails(contextDetails);
+    const navigable = lazy.TabManager.getNavigableForBrowsingContext(context);
+    const navigableId = lazy.TabManager.getIdForBrowsingContext(context);
+
+    let navigation = this.#navigations.get(navigable);
+    if (navigation && !navigation.finished) {
+      // If we are already monitoring a navigation for this navigable, for which
+      // we did not receive a navigation-stopped event, this navigation
+      // is already tracked and we don't want to create another id & event.
+      lazy.logger.trace(
+        `[${navigableId}] Skipping already tracked navigation, navigationId: ${navigation.navigationId}`
+      );
+      return navigation;
+    }
+
+    const navigationId = this.#getOrCreateNavigationId(navigableId);
+    navigation = { finished: false, navigationId, url };
+    this.#navigations.set(navigable, navigation);
+
+    lazy.logger.trace(
+      lazy.truncate`[${navigableId}] Navigation started for url: ${url} (${navigationId})`
+    );
+
+    this.emit("navigation-started", { navigationId, navigableId, url });
+
+    return navigation;
+  }
+
+  /**
+   * Called when a navigation-stopped event is recorded from the
+   * NavigationListener actors.
+   *
+   * @param {object} data
+   * @param {BrowsingContextDetails} data.contextDetails
+   *     The details about the browsing context for this navigation.
+   * @param {string} data.url
+   *     The URL as string for the navigation.
+   * @returns {NavigationInfo}
+   *     The stopped navigation if any, or null.
+   */
+  notifyNavigationStopped(data) {
+    const { contextDetails, url } = data;
+
+    const context = this.#getContextFromContextDetails(contextDetails);
+    const navigable = lazy.TabManager.getNavigableForBrowsingContext(context);
+    const navigableId = lazy.TabManager.getIdForBrowsingContext(context);
+
+    const navigation = this.#navigations.get(navigable);
+    if (!navigation) {
+      lazy.logger.trace(
+        lazy.truncate`[${navigableId}] No navigation found to stop for url: ${url}`
+      );
+      return null;
+    }
+
+    if (navigation.finished) {
+      lazy.logger.trace(
+        `[${navigableId}] Navigation already marked as finished, navigationId: ${navigation.navigationId}`
+      );
+      return navigation;
+    }
+
+    lazy.logger.trace(
+      lazy.truncate`[${navigableId}] Navigation finished for url: ${url} (${navigation.navigationId})`
+    );
+
+    navigation.finished = true;
+
+    this.emit("navigation-stopped", {
+      navigationId: navigation.navigationId,
+      navigableId,
+      url,
+    });
+
+    return navigation;
+  }
+
+  /**
+   * Register a navigation id to be used for the next navigation for the
+   * provided browsing context details.
+   *
+   * @param {object} data
+   * @param {BrowsingContextDetails} data.contextDetails
+   *     The details about the browsing context for this navigation.
+   * @returns {string}
+   *     The UUID created the upcoming navigation.
+   */
+  registerNavigationId(data) {
+    const { contextDetails } = data;
+    const context = this.#getContextFromContextDetails(contextDetails);
+    const navigableId = lazy.TabManager.getIdForBrowsingContext(context);
+
+    const navigationId = lazy.generateUUID();
+    this.#navigationIds.set(navigableId, navigationId);
+
+    return navigationId;
+  }
+
+  #getContextFromContextDetails(contextDetails) {
+    if (contextDetails.context) {
+      return contextDetails.context;
+    }
+
+    return contextDetails.isTopBrowsingContext
+      ? BrowsingContext.getCurrentTopByBrowserId(contextDetails.browserId)
+      : BrowsingContext.get(contextDetails.browsingContextId);
+  }
+
+  #getOrCreateNavigationId(navigableId) {
+    let navigationId;
+    if (this.#navigationIds.has(navigableId)) {
+      navigationId = this.#navigationIds.get(navigableId, navigationId);
+      this.#navigationIds.delete(navigableId);
+    } else {
+      navigationId = lazy.generateUUID();
+    }
+    return navigationId;
+  }
+}
+
+// Create a private NavigationRegistry singleton.
+const navigationRegistry = new NavigationRegistry();
+
+/**
+ * See NavigationRegistry.notifyLocationChanged.
+ *
+ * This entry point is only intended to be called from NavigationListenerParent,
+ * to avoid setting up observers or listeners, which are unnecessary since
+ * NavigationRegistry has to be a singleton.
+ */
+export function notifyLocationChanged(data) {
+  return navigationRegistry.notifyLocationChanged(data);
+}
+
+/**
+ * See NavigationRegistry.notifyNavigationStarted.
+ *
+ * This entry point is only intended to be called from NavigationListenerParent,
+ * to avoid setting up observers or listeners, which are unnecessary since
+ * NavigationRegistry has to be a singleton.
+ */
+export function notifyNavigationStarted(data) {
+  return navigationRegistry.notifyNavigationStarted(data);
+}
+
+/**
+ * See NavigationRegistry.notifyNavigationStopped.
+ *
+ * This entry point is only intended to be called from NavigationListenerParent,
+ * to avoid setting up observers or listeners, which are unnecessary since
+ * NavigationRegistry has to be a singleton.
+ */
+export function notifyNavigationStopped(data) {
+  return navigationRegistry.notifyNavigationStopped(data);
+}
+
+export function registerNavigationId(data) {
+  return navigationRegistry.registerNavigationId(data);
+}
+
+/**
+ * The NavigationManager exposes the NavigationRegistry data via a class which
+ * needs to be individually instantiated by each consumer. This allow to track
+ * how many consumers need navigation data at any point so that the
+ * NavigationRegistry can register or unregister the underlying JSWindowActors
+ * correctly.
+ *
+ * @fires navigation-started
+ *    The NavigationManager emits "navigation-started" when a new navigation is
+ *    detected, with the following object as payload:
+ *      - {string} navigationId - The UUID for the navigation.
+ *      - {string} navigableId - The UUID for the navigable.
+ *      - {string} url - The target url for the navigation.
+ * @fires navigation-stopped
+ *    The NavigationManager emits "navigation-stopped" when a known navigation
+ *    is stopped, with the following object as payload:
+ *      - {string} navigationId - The UUID for the navigation.
+ *      - {string} navigableId - The UUID for the navigable.
+ *      - {string} url - The target url for the navigation.
+ */
+export class NavigationManager extends EventEmitter {
+  #monitoring;
+
+  constructor() {
+    super();
+
+    this.#monitoring = false;
+  }
+
+  destroy() {
+    this.stopMonitoring();
+  }
+
+  getNavigationForBrowsingContext(context) {
+    return navigationRegistry.getNavigationForBrowsingContext(context);
+  }
+
+  startMonitoring() {
+    if (this.#monitoring) {
+      return;
+    }
+
+    this.#monitoring = true;
+    navigationRegistry.startMonitoring(this);
+    navigationRegistry.on("navigation-started", this.#onNavigationEvent);
+    navigationRegistry.on("location-changed", this.#onNavigationEvent);
+    navigationRegistry.on("navigation-stopped", this.#onNavigationEvent);
+  }
+
+  stopMonitoring() {
+    if (!this.#monitoring) {
+      return;
+    }
+
+    this.#monitoring = false;
+    navigationRegistry.stopMonitoring(this);
+    navigationRegistry.off("navigation-started", this.#onNavigationEvent);
+    navigationRegistry.off("location-changed", this.#onNavigationEvent);
+    navigationRegistry.off("navigation-stopped", this.#onNavigationEvent);
+  }
+
+  #onNavigationEvent = (eventName, data) => {
+    this.emit(eventName, data);
+  };
+}