1 files changed, 254 insertions, 0 deletions
diff --git a/mobile/android/modules/SharedPreferences.jsm b/mobile/android/modules/SharedPreferences.jsm
new file mode 100644
index 000000000..3f32df6ea
--- /dev/null
+++ b/mobile/android/modules/SharedPreferences.jsm
@@ -0,0 +1,254 @@
+// -*- indent-tabs-mode: nil; js-indent-level: 2 -*-
+/* 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/. */
+
+"use strict";
+
+this.EXPORTED_SYMBOLS = ["SharedPreferences"];
+
+const { classes: Cc, interfaces: Ci, utils: Cu } = Components;
+
+// For adding observers.
+Cu.import("resource://gre/modules/Services.jsm");
+Cu.import("resource://gre/modules/Messaging.jsm");
+
+var Scope = Object.freeze({
+  APP:          "app",
+  PROFILE:      "profile",
+  GLOBAL:       "global"
+});
+
+/**
+ * Public API to getting a SharedPreferencesImpl instance. These scopes mirror GeckoSharedPrefs.
+ */
+var SharedPreferences = {
+  forApp: function() {
+    return new SharedPreferencesImpl({ scope: Scope.APP });
+  },
+
+  forProfile: function() {
+    return new SharedPreferencesImpl({ scope: Scope.PROFILE });
+  },
+
+  /**
+   * Get SharedPreferences for the named profile; if the profile name is null,
+   * returns the preferences for the current profile (just like |forProfile|).
+   */
+  forProfileName: function(profileName) {
+    return new SharedPreferencesImpl({ scope: Scope.PROFILE, profileName: profileName });
+  },
+
+  /**
+   * Get SharedPreferences for the given Android branch; if the branch is null,
+   * returns the default preferences branch for the application, which is the
+   * output of |PreferenceManager.getDefaultSharedPreferences|.
+   */
+  forAndroid: function(branch) {
+    return new SharedPreferencesImpl({ scope: Scope.GLOBAL, branch: branch });
+  }
+};
+
+/**
+ * Create an interface to an Android SharedPreferences branch.
+ *
+ * options {Object} with the following valid keys:
+ *   - scope {String} (required) specifies the scope of preferences that should be accessed.
+ *   - branch {String} (only when using Scope.GLOBAL) should be a string describing a preferences branch,
+ *     like "UpdateService" or "background.data", or null to access the
+ *     default preferences branch for the application.
+ *   - profileName {String} (optional, only valid when using Scope.PROFILE)
+ */
+function SharedPreferencesImpl(options = {}) {
+  if (!(this instanceof SharedPreferencesImpl)) {
+    return new SharedPreferencesImpl(options);
+  }
+
+  if (options.scope == null || options.scope == undefined) {
+    throw "Shared Preferences must specifiy a scope.";
+  }
+
+  this._scope = options.scope;
+  this._profileName = options.profileName;
+  this._branch = options.branch;
+  this._observers = {};
+}
+
+SharedPreferencesImpl.prototype = Object.freeze({
+  _set: function _set(prefs) {
+    Messaging.sendRequest({
+      type: "SharedPreferences:Set",
+      preferences: prefs,
+      scope: this._scope,
+      profileName: this._profileName,
+      branch: this._branch,
+    });
+  },
+
+  _setOne: function _setOne(prefName, value, type) {
+    let prefs = [];
+    prefs.push({
+      name: prefName,
+      value: value,
+      type: type,
+    });
+    this._set(prefs);
+  },
+
+  setBoolPref: function setBoolPref(prefName, value) {
+    this._setOne(prefName, value, "bool");
+  },
+
+  setCharPref: function setCharPref(prefName, value) {
+    this._setOne(prefName, value, "string");
+  },
+
+  setIntPref: function setIntPref(prefName, value) {
+    this._setOne(prefName, value, "int");
+  },
+
+  _get: function _get(prefs, callback) {
+    let result = null;
+    Messaging.sendRequestForResult({
+      type: "SharedPreferences:Get",
+      preferences: prefs,
+      scope: this._scope,
+      profileName: this._profileName,
+      branch: this._branch,
+    }).then((data) => {
+      result = data.values;
+    });
+
+    let thread = Services.tm.currentThread;
+    while (result == null)
+      thread.processNextEvent(true);
+
+    return result;
+  },
+
+  _getOne: function _getOne(prefName, type) {
+    let prefs = [];
+    prefs.push({
+      name: prefName,
+      type: type,
+    });
+    let values = this._get(prefs);
+    if (values.length != 1) {
+      throw new Error("Got too many values: " + values.length);
+    }
+    return values[0].value;
+  },
+
+  getBoolPref: function getBoolPref(prefName) {
+    return this._getOne(prefName, "bool");
+  },
+
+  getCharPref: function getCharPref(prefName) {
+    return this._getOne(prefName, "string");
+  },
+
+  getIntPref: function getIntPref(prefName) {
+    return this._getOne(prefName, "int");
+  },
+
+  /**
+   * Invoke `observer` after a change to the preference `domain` in
+   * the current branch.
+   *
+   * `observer` should implement the nsIObserver.observe interface.
+   */
+  addObserver: function addObserver(domain, observer, holdWeak) {
+    if (!domain)
+      throw new Error("domain must not be null");
+    if (!observer)
+      throw new Error("observer must not be null");
+    if (holdWeak)
+      throw new Error("Weak references not yet implemented.");
+
+    if (!this._observers.hasOwnProperty(domain))
+      this._observers[domain] = [];
+    if (this._observers[domain].indexOf(observer) > -1)
+      return;
+
+    this._observers[domain].push(observer);
+
+    this._updateAndroidListener();
+  },
+
+  /**
+   * Do not invoke `observer` after a change to the preference
+   * `domain` in the current branch.
+   */
+  removeObserver: function removeObserver(domain, observer) {
+    if (!this._observers.hasOwnProperty(domain))
+      return;
+    let index = this._observers[domain].indexOf(observer);
+    if (index < 0)
+      return;
+
+    this._observers[domain].splice(index, 1);
+    if (this._observers[domain].length < 1)
+      delete this._observers[domain];
+
+    this._updateAndroidListener();
+  },
+
+  _updateAndroidListener: function _updateAndroidListener() {
+    if (this._listening && Object.keys(this._observers).length < 1)
+      this._uninstallAndroidListener();
+    if (!this._listening && Object.keys(this._observers).length > 0)
+      this._installAndroidListener();
+  },
+
+  _installAndroidListener: function _installAndroidListener() {
+    if (this._listening)
+      return;
+    this._listening = true;
+
+    Services.obs.addObserver(this, "SharedPreferences:Changed", false);
+    Messaging.sendRequest({
+      type: "SharedPreferences:Observe",
+      enable: true,
+      scope: this._scope,
+      profileName: this._profileName,
+      branch: this._branch,
+    });
+  },
+
+  observe: function observe(subject, topic, data) {
+    if (topic != "SharedPreferences:Changed") {
+      return;
+    }
+
+    let msg = JSON.parse(data);
+    if (msg.scope !== this._scope ||
+        ((this._scope === Scope.PROFILE) && (msg.profileName !== this._profileName)) ||
+        ((this._scope === Scope.GLOBAL)  && (msg.branch !== this._branch))) {
+      return;
+    }
+
+    if (!this._observers.hasOwnProperty(msg.key)) {
+      return;
+    }
+
+    let observers = this._observers[msg.key];
+    for (let obs of observers) {
+      obs.observe(obs, msg.key, msg.value);
+    }
+  },
+
+  _uninstallAndroidListener: function _uninstallAndroidListener() {
+    if (!this._listening)
+      return;
+    this._listening = false;
+
+    Services.obs.removeObserver(this, "SharedPreferences:Changed");
+    Messaging.sendRequest({
+      type: "SharedPreferences:Observe",
+      enable: false,
+      scope: this._scope,
+      profileName: this._profileName,
+      branch: this._branch,
+    });
+  },
+});