/* 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";

const {utils: Cu} = Components;
Cu.import("resource://gre/modules/Preferences.jsm");
Cu.import("resource://gre/modules/Services.jsm");

const ACTIVITY_STREAM_PREF_BRANCH = "browser.newtabpage.activity-stream.";

this.Prefs = class Prefs extends Preferences {

  /**
   * Prefs - A wrapper around Preferences that always sets the branch to
   *         ACTIVITY_STREAM_PREF_BRANCH
   */
  constructor(branch = ACTIVITY_STREAM_PREF_BRANCH) {
    super({branch});
    this._branchName = branch;
  }
  get branchName() {
    return this._branchName;
  }
};

this.DefaultPrefs = class DefaultPrefs {

  /**
   * DefaultPrefs - A helper for setting and resetting default prefs for the add-on
   *
   * @param  {Array} config An array of configuration objects with the following properties:
   *         {string} .name The name of the pref
   *         {string} .title (optional) A description of the pref
   *         {bool|string|number} .value The default value for the pref
   * @param  {string} branch (optional) The pref branch (defaults to ACTIVITY_STREAM_PREF_BRANCH)
   */
  constructor(config, branch = ACTIVITY_STREAM_PREF_BRANCH) {
    this._config = config;
    this.branch = Services.prefs.getDefaultBranch(branch);
  }

  /**
   * _setDefaultPref - Sets the default value (not user-defined) for a given pref
   *
   * @param  {string} key The name of the pref
   * @param  {type} val The default value of the pref
   */
  _setDefaultPref(key, val) {
    switch (typeof val) {
      case "boolean":
        this.branch.setBoolPref(key, val);
        break;
      case "number":
        this.branch.setIntPref(key, val);
        break;
      case "string":
        this.branch.setStringPref(key, val);
        break;
    }
  }

  /**
   * init - Set default prefs for all prefs in the config
   */
  init() {
    for (const pref of this._config) {
      this._setDefaultPref(pref.name, pref.value);
    }
  }

  /**
   * reset - Resets all user-defined prefs for prefs in ._config to their defaults
   */
  reset() {
    for (const pref of this._config) {
      this.branch.clearUserPref(pref.name);
    }
  }
};

this.EXPORTED_SYMBOLS = ["DefaultPrefs", "Prefs"];