gecko-dev/browser/extensions/pdfjs/content/PdfjsContentUtils.jsm

/* Copyright 2012 Mozilla Foundation
 *
 * Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

"use strict";

var EXPORTED_SYMBOLS = ["PdfjsContentUtils"];

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

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

var PdfjsContentUtils = {
  _mm: null,

  /*
   * Public API
   */

  get isRemote() {
    return (Services.appinfo.processType ===
            Services.appinfo.PROCESS_TYPE_CONTENT);
  },

  init() {
    // child *process* mm, or when loaded into the parent for in-content
    // support the psuedo child process mm 'child PPMM'.
    if (!this._mm) {
      this._mm = Cc["@mozilla.org/childprocessmessagemanager;1"].
        getService(Ci.nsISyncMessageSender);
      this._mm.addMessageListener("PDFJS:Child:updateSettings", this);

      Services.obs.addObserver(this, "quit-application");
    }
  },

  uninit() {
    if (this._mm) {
      this._mm.removeMessageListener("PDFJS:Child:updateSettings", this);
      Services.obs.removeObserver(this, "quit-application");
    }
    this._mm = null;
  },

  /*
   * prefs utilities - the child does not have write access to prefs.
   * note, the pref names here are cross-checked against a list of
   * approved pdfjs prefs in chrome utils.
   */

  clearUserPref(aPrefName) {
    this._mm.sendSyncMessage("PDFJS:Parent:clearUserPref", {
      name: aPrefName,
    });
  },

  setIntPref(aPrefName, aPrefValue) {
    this._mm.sendSyncMessage("PDFJS:Parent:setIntPref", {
      name: aPrefName,
      value: aPrefValue,
    });
  },

  setBoolPref(aPrefName, aPrefValue) {
    this._mm.sendSyncMessage("PDFJS:Parent:setBoolPref", {
      name: aPrefName,
      value: aPrefValue,
    });
  },

  setCharPref(aPrefName, aPrefValue) {
    this._mm.sendSyncMessage("PDFJS:Parent:setCharPref", {
      name: aPrefName,
      value: aPrefValue,
    });
  },

  setStringPref(aPrefName, aPrefValue) {
    this._mm.sendSyncMessage("PDFJS:Parent:setStringPref", {
      name: aPrefName,
      value: aPrefValue,
    });
  },

  /*
   * Request the display of a notification warning in the associated window
   * when the renderer isn't sure a pdf displayed correctly.
   */
  displayWarning(aWindow, aMessage, aLabel, aAccessKey) {
    // the child's dom frame mm associated with the window.
    let winmm = aWindow.QueryInterface(Ci.nsIInterfaceRequestor)
                       .getInterface(Ci.nsIDocShell)
                       .QueryInterface(Ci.nsIInterfaceRequestor)
                       .getInterface(Ci.nsIContentFrameMessageManager);
    winmm.sendAsyncMessage("PDFJS:Parent:displayWarning", {
      message: aMessage,
      label: aLabel,
      accessKey: aAccessKey,
    });
  },

  /*
   * Events
   */

  observe(aSubject, aTopic, aData) {
    if (aTopic === "quit-application") {
      this.uninit();
    }
  },

  receiveMessage(aMsg) {
    switch (aMsg.name) {
      case "PDFJS:Child:updateSettings":
        // Only react to this if we are remote.
        if (Services.appinfo.processType ===
            Services.appinfo.PROCESS_TYPE_CONTENT) {
          let jsm = "resource://pdf.js/PdfJs.jsm";
          let pdfjs = Components.utils.import(jsm, {}).PdfJs;
          if (aMsg.data.enabled) {
            pdfjs.ensureRegistered();
          } else {
            pdfjs.ensureUnregistered();
          }
        }
        break;
    }
  },
};