1 files changed, 285 insertions, 0 deletions
diff --git a/services/sync/modules/UIState.sys.mjs b/services/sync/modules/UIState.sys.mjs
new file mode 100644
index 0000000000..8981d81f7d
--- /dev/null
+++ b/services/sync/modules/UIState.sys.mjs
@@ -0,0 +1,285 @@
+/* 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/. */
+
+/**
+ * @typedef {Object} UIState
+ * @property {string} status The Sync/FxA status, see STATUS_* constants.
+ * @property {string} [email] The FxA email configured to log-in with Sync.
+ * @property {string} [displayName] The user's FxA display name.
+ * @property {string} [avatarURL] The user's FxA avatar URL.
+ * @property {Date} [lastSync] The last sync time.
+ * @property {boolean} [syncing] Whether or not we are currently syncing.
+ */
+
+const lazy = {};
+ChromeUtils.defineESModuleGetters(lazy, {
+  LOGIN_FAILED_LOGIN_REJECTED: "resource://services-sync/constants.sys.mjs",
+  Weave: "resource://services-sync/main.sys.mjs",
+});
+
+const TOPICS = [
+  "weave:connected",
+  "weave:service:login:got-hashed-id",
+  "weave:service:login:error",
+  "weave:service:ready",
+  "weave:service:sync:start",
+  "weave:service:sync:finish",
+  "weave:service:sync:error",
+  "weave:service:start-over:finish",
+  "fxaccounts:onverified",
+  "fxaccounts:onlogin", // Defined in FxAccountsCommon, pulling it is expensive.
+  "fxaccounts:onlogout",
+  "fxaccounts:profilechange",
+  "fxaccounts:statechange",
+];
+
+const ON_UPDATE = "sync-ui-state:update";
+
+const STATUS_NOT_CONFIGURED = "not_configured";
+const STATUS_LOGIN_FAILED = "login_failed";
+const STATUS_NOT_VERIFIED = "not_verified";
+const STATUS_SIGNED_IN = "signed_in";
+
+const DEFAULT_STATE = {
+  status: STATUS_NOT_CONFIGURED,
+};
+
+const UIStateInternal = {
+  _initialized: false,
+  _state: null,
+
+  // We keep _syncing out of the state object because we can only track it
+  // using sync events and we can't determine it at any point in time.
+  _syncing: false,
+
+  get state() {
+    if (!this._state) {
+      return DEFAULT_STATE;
+    }
+    return Object.assign({}, this._state, { syncing: this._syncing });
+  },
+
+  isReady() {
+    if (!this._initialized) {
+      this.init();
+      return false;
+    }
+    return true;
+  },
+
+  init() {
+    this._initialized = true;
+    // Because the FxA toolbar is usually visible, this module gets loaded at
+    // browser startup, and we want to avoid pulling in all of FxA or Sync at
+    // that time, so we refresh the state after the browser has settled.
+    Services.tm.idleDispatchToMainThread(() => {
+      this.refreshState().catch(e => {
+        console.error(e);
+      });
+    }, 2000);
+  },
+
+  // Used for testing.
+  reset() {
+    this._state = null;
+    this._syncing = false;
+    this._initialized = false;
+  },
+
+  observe(subject, topic, data) {
+    switch (topic) {
+      case "weave:service:sync:start":
+        this.toggleSyncActivity(true);
+        break;
+      case "weave:service:sync:finish":
+      case "weave:service:sync:error":
+        this.toggleSyncActivity(false);
+        break;
+      default:
+        this.refreshState().catch(e => {
+          console.error(e);
+        });
+        break;
+    }
+  },
+
+  // Builds a new state from scratch.
+  async refreshState() {
+    const newState = {};
+    await this._refreshFxAState(newState);
+    // Optimize the "not signed in" case to avoid refreshing twice just after
+    // startup - if there's currently no _state, and we still aren't configured,
+    // just early exit.
+    if (this._state == null && newState.status == DEFAULT_STATE.status) {
+      return this.state;
+    }
+    if (newState.syncEnabled) {
+      this._setLastSyncTime(newState); // We want this in case we change accounts.
+    }
+    this._state = newState;
+
+    this.notifyStateUpdated();
+    return this.state;
+  },
+
+  // Update the current state with the last sync time/currently syncing status.
+  toggleSyncActivity(syncing) {
+    this._syncing = syncing;
+    this._setLastSyncTime(this._state);
+
+    this.notifyStateUpdated();
+  },
+
+  notifyStateUpdated() {
+    Services.obs.notifyObservers(null, ON_UPDATE);
+  },
+
+  async _refreshFxAState(newState) {
+    let userData = await this._getUserData();
+    await this._populateWithUserData(newState, userData);
+  },
+
+  async _populateWithUserData(state, userData) {
+    let status;
+    let syncUserName = Services.prefs.getStringPref(
+      "services.sync.username",
+      ""
+    );
+    if (!userData) {
+      // If Sync thinks it is configured but there's no FxA user, then we
+      // want to enter the "login failed" state so the user can get
+      // reconfigured.
+      if (syncUserName) {
+        state.email = syncUserName;
+        status = STATUS_LOGIN_FAILED;
+      } else {
+        // everyone agrees nothing is configured.
+        status = STATUS_NOT_CONFIGURED;
+      }
+    } else {
+      let loginFailed = await this._loginFailed();
+      if (loginFailed) {
+        status = STATUS_LOGIN_FAILED;
+      } else if (!userData.verified) {
+        status = STATUS_NOT_VERIFIED;
+      } else {
+        status = STATUS_SIGNED_IN;
+      }
+      state.uid = userData.uid;
+      state.email = userData.email;
+      state.displayName = userData.displayName;
+      // for better or worse, this module renames these attribues.
+      state.avatarURL = userData.avatar;
+      state.avatarIsDefault = userData.avatarDefault;
+      state.syncEnabled = !!syncUserName;
+    }
+    state.status = status;
+  },
+
+  async _getUserData() {
+    try {
+      return await this.fxAccounts.getSignedInUser();
+    } catch (e) {
+      // This is most likely in tests, where we quickly log users in and out.
+      // The most likely scenario is a user logged out, so reflect that.
+      // Bug 995134 calls for better errors so we could retry if we were
+      // sure this was the failure reason.
+      console.error("Error updating FxA account info:", e);
+      return null;
+    }
+  },
+
+  _setLastSyncTime(state) {
+    if (state?.status == UIState.STATUS_SIGNED_IN) {
+      const lastSync = Services.prefs.getStringPref(
+        "services.sync.lastSync",
+        null
+      );
+      state.lastSync = lastSync ? new Date(lastSync) : null;
+    }
+  },
+
+  async _loginFailed() {
+    // First ask FxA if it thinks the user needs re-authentication. In practice,
+    // this check is probably canonical (ie, we probably don't really need
+    // the check below at all as we drop local session info on the first sign
+    // of a problem) - but we keep it for now to keep the risk down.
+    let hasLocalSession = await this.fxAccounts.hasLocalSession();
+    if (!hasLocalSession) {
+      return true;
+    }
+
+    // Referencing Weave.Service will implicitly initialize sync, and we don't
+    // want to force that - so first check if it is ready.
+    let service = Cc["@mozilla.org/weave/service;1"].getService(
+      Ci.nsISupports
+    ).wrappedJSObject;
+    if (!service.ready) {
+      return false;
+    }
+    // LOGIN_FAILED_LOGIN_REJECTED explicitly means "you must log back in".
+    // All other login failures are assumed to be transient and should go
+    // away by themselves, so aren't reflected here.
+    return lazy.Weave.Status.login == lazy.LOGIN_FAILED_LOGIN_REJECTED;
+  },
+
+  set fxAccounts(mockFxAccounts) {
+    delete this.fxAccounts;
+    this.fxAccounts = mockFxAccounts;
+  },
+};
+
+ChromeUtils.defineLazyGetter(UIStateInternal, "fxAccounts", () => {
+  return ChromeUtils.importESModule(
+    "resource://gre/modules/FxAccounts.sys.mjs"
+  ).getFxAccountsSingleton();
+});
+
+for (let topic of TOPICS) {
+  Services.obs.addObserver(UIStateInternal, topic);
+}
+
+export var UIState = {
+  _internal: UIStateInternal,
+
+  ON_UPDATE,
+
+  STATUS_NOT_CONFIGURED,
+  STATUS_LOGIN_FAILED,
+  STATUS_NOT_VERIFIED,
+  STATUS_SIGNED_IN,
+
+  /**
+   * Returns true if the module has been initialized and the state set.
+   * If not, return false and trigger an init in the background.
+   */
+  isReady() {
+    return this._internal.isReady();
+  },
+
+  /**
+   * @returns {UIState} The current Sync/FxA UI State.
+   */
+  get() {
+    return this._internal.state;
+  },
+
+  /**
+   * Refresh the state. Used for testing, don't call this directly since
+   * UIState already listens to Sync/FxA notifications to determine if the state
+   * needs to be refreshed. ON_UPDATE will be fired once the state is refreshed.
+   *
+   * @returns {Promise<UIState>} Resolved once the state is refreshed.
+   */
+  refresh() {
+    return this._internal.refreshState();
+  },
+
+  /**
+   * Reset the state of the whole module. Used for testing.
+   */
+  reset() {
+    this._internal.reset();
+  },
+};