/* 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 Ci = Components.interfaces;
const Cu = Components.utils;

Cu.import("resource://gre/modules/XPCOMUtils.jsm");
Cu.import("resource://gre/modules/Services.jsm");
Cu.import("resource://gre/modules/ObjectWrapper.jsm");

XPCOMUtils.defineLazyServiceGetter(this, "cpmm",
  "@mozilla.org/childprocessmessagemanager;1", "nsIMessageSender");

XPCOMUtils.defineLazyServiceGetter(this, "tm",
  "@mozilla.org/thread-manager;1", "nsIThreadManager");

// -----------------------------------------------------------------------
// MozKeyboard
// -----------------------------------------------------------------------

function MozKeyboard() { }

MozKeyboard.prototype = {
  classID: Components.ID("{397a7fdf-2254-47be-b74e-76625a1a66d5}"),

  QueryInterface: XPCOMUtils.generateQI([
    Ci.nsIB2GKeyboard, Ci.nsIDOMGlobalPropertyInitializer, Ci.nsIObserver
  ]),

  classInfo: XPCOMUtils.generateCI({
    "classID": Components.ID("{397a7fdf-2254-47be-b74e-76625a1a66d5}"),
    "contractID": "@mozilla.org/b2g-keyboard;1",
    "interfaces": [Ci.nsIB2GKeyboard],
    "flags": Ci.nsIClassInfo.DOM_OBJECT,
    "classDescription": "B2G Virtual Keyboard"
  }),

  init: function mozKeyboardInit(win) {
    let principal = win.document.nodePrincipal;
    let perm = Services.perms
               .testExactPermissionFromPrincipal(principal, "keyboard");
    if (perm != Ci.nsIPermissionManager.ALLOW_ACTION) {
      dump("No permission to use the keyboard API for " +
           principal.origin + "\n");
      return null;
    }

    Services.obs.addObserver(this, "inner-window-destroyed", false);
    cpmm.addMessageListener('Keyboard:FocusChange', this);

    this._window = win;
    this._utils = win.QueryInterface(Ci.nsIInterfaceRequestor)
                     .getInterface(Ci.nsIDOMWindowUtils);
    this.innerWindowID = this._utils.currentInnerWindowID;
    this._focusHandler = null;
  },

  uninit: function mozKeyboardUninit() {
    Services.obs.removeObserver(this, "inner-window-destroyed");
    cpmm.removeMessageListener('Keyboard:FocusChange', this);

    this._window = null;
    this._utils = null;
    this._focusHandler = null;
  },

  sendKey: function mozKeyboardSendKey(keyCode, charCode) {
    charCode = (charCode == undefined) ? keyCode : charCode;

    let mainThread = tm.mainThread;
    let utils = this._utils;

    function send(type) {
      mainThread.dispatch(function() {
	utils.sendKeyEvent(type, keyCode, charCode, null);
      }, mainThread.DISPATCH_NORMAL);
    }

    send("keydown");
    send("keypress");
    send("keyup");
  },

  setSelectedOption: function mozKeyboardSetSelectedOption(index) {
    cpmm.sendAsyncMessage('Keyboard:SetSelectedOption', {
      'index': index
    });
  },

  setValue: function mozKeyboardSetValue(value) {
    cpmm.sendAsyncMessage('Keyboard:SetValue', {
      'value': value
    });
  },

  setSelectedOptions: function mozKeyboardSetSelectedOptions(indexes) {
    cpmm.sendAsyncMessage('Keyboard:SetSelectedOptions', {
      'indexes': indexes
    });
  },

  removeFocus: function mozKeyboardRemoveFocus() {
    cpmm.sendAsyncMessage('Keyboard:RemoveFocus', {});
  },

  set onfocuschange(val) {
    this._focusHandler = val;
  },

  get onfocuschange() {
    return this._focusHandler;
  },

  replaceSurroundingText: function mozKeyboardReplaceSurroundingText(
    text, beforeLength, afterLength) {
    cpmm.sendAsyncMessage('Keyboard:ReplaceSurroundingText', {
      'text': text || '',
      'beforeLength': (typeof beforeLength === 'number' ? beforeLength : 0),
      'afterLength': (typeof afterLength === 'number' ? afterLength: 0)
    });
  },

  receiveMessage: function mozKeyboardReceiveMessage(msg) {
    let handler = this._focusHandler;
    if (!handler || !(handler instanceof Ci.nsIDOMEventListener))
      return;

    let detail = {
      "detail": msg.json
    };

    let evt = new this._window.CustomEvent("focuschanged",
                                           ObjectWrapper.wrap(detail, this._window));
    handler.handleEvent(evt);
  },

  observe: function mozKeyboardObserve(subject, topic, data) {
    let wId = subject.QueryInterface(Ci.nsISupportsPRUint64).data;
    if (wId == this.innerWindowID)
      this.uninit();
  }
};

this.NSGetFactory = XPCOMUtils.generateNSGetFactory([MozKeyboard]);
