gecko-dev/services/sync/modules/ext/Preferences.js

/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Preferences.
 *
 * The Initial Developer of the Original Code is Mozilla.
 * Portions created by the Initial Developer are Copyright (C) 2008
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Myk Melez <myk@mozilla.org>
 *   Daniel Aquino <mr.danielaquino@gmail.com>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

let EXPORTED_SYMBOLS = ["Preferences"];

const Cc = Components.classes;
const Ci = Components.interfaces;
const Cr = Components.results;
const Cu = Components.utils;

function Preferences(prefBranch) {
  if (prefBranch)
    this._prefBranch = prefBranch;
}

Preferences.prototype = {
  _prefBranch: "",

  // Preferences Service

  get _prefSvc() {
    let prefSvc = Cc["@mozilla.org/preferences-service;1"].
                  getService(Ci.nsIPrefService).
                  getBranch(this._prefBranch).
                  QueryInterface(Ci.nsIPrefBranch2);
    this.__defineGetter__("_prefSvc", function() prefSvc);
    return this._prefSvc;
  },

  /**
    * Get the value of a pref, if any; otherwise return the default value.
    *
    * @param   prefName      the name of the pref to get
    * @param   defaultValue  the default value, if any
    *
    * @returns the value of the pref, if any; otherwise the default value
    */
  get: function(prefName, defaultValue) {
    // We can't check for |prefName.constructor == Array| here, since we have
    // a different global object, so we check the constructor name instead.
    if (typeof prefName == "object" && prefName.constructor.name == Array.name)
      return prefName.map(function(v) this.get(v), this);

    switch (this._prefSvc.getPrefType(prefName)) {
      case Ci.nsIPrefBranch.PREF_STRING:
        return this._prefSvc.getCharPref(prefName);

      case Ci.nsIPrefBranch.PREF_INT:
        return this._prefSvc.getIntPref(prefName);

      case Ci.nsIPrefBranch.PREF_BOOL:
        return this._prefSvc.getBoolPref(prefName);

      case Ci.nsIPrefBranch.PREF_INVALID:
      default:
        return defaultValue;
    }
  },

  set: function(prefName, prefValue) {
    // We can't check for |prefName.constructor == Object| here, since we have
    // a different global object, so we check the constructor name instead.
    if (typeof prefName == "object" && prefName.constructor.name == Object.name)
      for (let [name, value] in Iterator(prefName))
        this.set(name, value);
    else {
      switch (typeof prefValue) {
        case "number":
          this._prefSvc.setIntPref(prefName, prefValue);
          break;

        case "boolean":
          this._prefSvc.setBoolPref(prefName, prefValue);
          break;

        case "string":
        default:
          this._prefSvc.setCharPref(prefName, prefValue);
          break;
      }
    }
  },

  // FIXME: make the methods below accept an array of pref names.

  has: function(prefName) {
    return (this._prefSvc.getPrefType(prefName) != Ci.nsIPrefBranch.PREF_INVALID);
  },

  modified: function(prefName) {
    return (this.has(prefName) && this._prefSvc.prefHasUserValue(prefName));
  },

  locked: function(prefName) {
    return this._prefSvc.isLocked(prefName);
  },

  lock: function(prefName) {
    this._prefSvc.lockPref(prefName);
  },

  unlock: function(prefName) {
    this._prefSvc.unlockPref(prefName);
  },

  reset: function(prefName) {
    this._prefSvc.clearUserPref(prefName);
  },

  resetBranch: function(prefBranch) {
    this._prefSvc.resetBranch(prefBranch);
  }

};

// Give the constructor the same prototype as its instances, so users can access
// preferences directly via the constructor without having to create an instance
// first.
Preferences.__proto__ = Preferences.prototype;