michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
michael@0:  * You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: // TODO Bug 907060 Per off-line discussion, after the MessagePort is done
michael@0: // at Bug 643325, we will start to refactorize the common logic of both
michael@0: // Inter-App Communication and Shared Worker. For now, we hope to design an
michael@0: // MozInterAppMessagePort to meet the timeline, which still follows exactly
michael@0: // the same interface and semantic as the MessagePort is. In the future,
michael@0: // we can then align it back to MessagePort with backward compatibility.
michael@0: 
michael@0: "use strict";
michael@0: 
michael@0: const { classes: Cc, interfaces: Ci, utils: Cu, results: Cr } = Components;
michael@0: 
michael@0: Cu.import("resource://gre/modules/Services.jsm");
michael@0: Cu.import("resource://gre/modules/XPCOMUtils.jsm");
michael@0: Cu.import("resource://gre/modules/DOMRequestHelper.jsm");
michael@0: 
michael@0: const DEBUG = false;
michael@0: function debug(aMsg) {
michael@0:   dump("-- InterAppMessagePort: " + Date.now() + ": " + aMsg + "\n");
michael@0: }
michael@0: 
michael@0: XPCOMUtils.defineLazyServiceGetter(this, "cpmm",
michael@0:                                    "@mozilla.org/childprocessmessagemanager;1",
michael@0:                                    "nsIMessageSender");
michael@0: 
michael@0: XPCOMUtils.defineLazyServiceGetter(this, "appsService",
michael@0:                                    "@mozilla.org/AppsService;1",
michael@0:                                    "nsIAppsService");
michael@0: 
michael@0: const kMessages = ["InterAppMessagePort:OnMessage"];
michael@0: 
michael@0: function InterAppMessagePort() {
michael@0:   if (DEBUG) debug("InterAppMessagePort()");
michael@0: };
michael@0: 
michael@0: InterAppMessagePort.prototype = {
michael@0:   __proto__: DOMRequestIpcHelper.prototype,
michael@0: 
michael@0:   classDescription: "MozInterAppMessagePort",
michael@0: 
michael@0:   classID: Components.ID("{c66e0f8c-e3cb-11e2-9e85-43ef6244b884}"),
michael@0: 
michael@0:   contractID: "@mozilla.org/dom/inter-app-message-port;1",
michael@0: 
michael@0:   QueryInterface: XPCOMUtils.generateQI([Ci.nsIDOMGlobalPropertyInitializer,
michael@0:                                          Ci.nsISupportsWeakReference,
michael@0:                                          Ci.nsIObserver]),
michael@0: 
michael@0:   // Ci.nsIDOMGlobalPropertyInitializer implementation.
michael@0:   init: function(aWindow) {
michael@0:     if (DEBUG) debug("Calling init().");
michael@0: 
michael@0:     this.initDOMRequestHelper(aWindow, kMessages);
michael@0: 
michael@0:     let principal = aWindow.document.nodePrincipal;
michael@0:     this._manifestURL = appsService.getManifestURLByLocalId(principal.appId);
michael@0:     this._pageURL = principal.URI.specIgnoringRef;
michael@0: 
michael@0:     // Remove query string.
michael@0:     this._pageURL = this._pageURL.split("?")[0];
michael@0: 
michael@0:     this._started = false;
michael@0:     this._closed = false;
michael@0:     this._messageQueue = [];
michael@0:   },
michael@0: 
michael@0:   // WebIDL implementation for constructor.
michael@0:   __init: function(aMessagePortID) {
michael@0:     if (DEBUG) {
michael@0:       debug("Calling __init(): aMessagePortID: " + aMessagePortID);
michael@0:     }
michael@0: 
michael@0:     this._messagePortID = aMessagePortID;
michael@0: 
michael@0:     cpmm.sendAsyncMessage("InterAppMessagePort:Register",
michael@0:                           { messagePortID: this._messagePortID,
michael@0:                             manifestURL: this._manifestURL,
michael@0:                             pageURL: this._pageURL });
michael@0:   },
michael@0: 
michael@0:   // DOMRequestIpcHelper implementation.
michael@0:   uninit: function() {
michael@0:     if (DEBUG) debug("Calling uninit().");
michael@0: 
michael@0:     // When the message port is uninitialized, we need to disentangle the
michael@0:     // coupling ports, as if the close() method had been called.
michael@0:     if (this._closed) {
michael@0:       if (DEBUG) debug("close() has been called. Don't need to close again.");
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     this.close();
michael@0:   },
michael@0: 
michael@0:   postMessage: function(aMessage) {
michael@0:     if (DEBUG) debug("Calling postMessage().");
michael@0: 
michael@0:     if (this._closed) {
michael@0:       if (DEBUG) debug("close() has been called. Cannot post message.");
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     cpmm.sendAsyncMessage("InterAppMessagePort:PostMessage",
michael@0:                           { messagePortID: this._messagePortID,
michael@0:                             manifestURL: this._manifestURL,
michael@0:                             message: aMessage });
michael@0:   },
michael@0: 
michael@0:   start: function() {
michael@0:     // Begin dispatching messages received on the port.
michael@0:     if (DEBUG) debug("Calling start().");
michael@0: 
michael@0:     if (this._closed) {
michael@0:       if (DEBUG) debug("close() has been called. Cannot call start().");
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     if (this._started) {
michael@0:       if (DEBUG) debug("start() has been called. Don't need to start again.");
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     // When a port's port message queue is enabled, the event loop must use it
michael@0:     // as one of its task sources.
michael@0:     this._started = true;
michael@0:     while (this._messageQueue.length) {
michael@0:       let message = this._messageQueue.shift();
michael@0:       this._dispatchMessage(message);
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   close: function() {
michael@0:     // Disconnecting the port, so that it is no longer active.
michael@0:     if (DEBUG) debug("Calling close().");
michael@0: 
michael@0:     if (this._closed) {
michael@0:       if (DEBUG) debug("close() has been called. Don't need to close again.");
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     this._closed = true;
michael@0:     this._messageQueue.length = 0;
michael@0: 
michael@0:     // When this method called on a local port that is entangled with another
michael@0:     // port, must cause the user agent to disentangle the coupling ports.
michael@0:     cpmm.sendAsyncMessage("InterAppMessagePort:Unregister",
michael@0:                           { messagePortID: this._messagePortID,
michael@0:                             manifestURL: this._manifestURL });
michael@0:   },
michael@0: 
michael@0:   get onmessage() {
michael@0:     if (DEBUG) debug("Getting onmessage handler.");
michael@0: 
michael@0:     return this.__DOM_IMPL__.getEventHandler("onmessage");
michael@0:   },
michael@0: 
michael@0:   set onmessage(aHandler) {
michael@0:     if (DEBUG) debug("Setting onmessage handler.");
michael@0: 
michael@0:     this.__DOM_IMPL__.setEventHandler("onmessage", aHandler);
michael@0: 
michael@0:     // The first time a MessagePort object's onmessage IDL attribute is set,
michael@0:     // the port's message queue must be enabled, as if the start() method had
michael@0:     // been called.
michael@0:     if (this._started) {
michael@0:       if (DEBUG) debug("start() has been called. Don't need to start again.");
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     this.start();
michael@0:   },
michael@0: 
michael@0:   _dispatchMessage: function _dispatchMessage(aMessage) {
michael@0:     let wrappedMessage = Cu.cloneInto(aMessage, this._window);
michael@0:     if (DEBUG) {
michael@0:       debug("_dispatchMessage: wrappedMessage: " +
michael@0:             JSON.stringify(wrappedMessage));
michael@0:     }
michael@0: 
michael@0:     let event = new this._window
michael@0:                     .MozInterAppMessageEvent("message",
michael@0:                                              { data: wrappedMessage });
michael@0:     this.__DOM_IMPL__.dispatchEvent(event);
michael@0:   },
michael@0: 
michael@0:   receiveMessage: function(aMessage) {
michael@0:     if (DEBUG) debug("receiveMessage: name: " + aMessage.name);
michael@0: 
michael@0:     let message = aMessage.json;
michael@0:     if (message.manifestURL != this._manifestURL ||
michael@0:         message.pageURL != this._pageURL ||
michael@0:         message.messagePortID != this._messagePortID) {
michael@0:       if (DEBUG) debug("The message doesn't belong to this page. Returning.");
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     switch (aMessage.name) {
michael@0:       case "InterAppMessagePort:OnMessage":
michael@0:         if (this._closed) {
michael@0:           if (DEBUG) debug("close() has been called. Drop the message.");
michael@0:           return;
michael@0:         }
michael@0: 
michael@0:         if (!this._started) {
michael@0:           if (DEBUG) debug("Not yet called start(). Queue up the message.");
michael@0:           this._messageQueue.push(message.message);
michael@0:           return;
michael@0:         }
michael@0: 
michael@0:         this._dispatchMessage(message.message);
michael@0:         break;
michael@0: 
michael@0:       default:
michael@0:         if (DEBUG) debug("Error! Shouldn't fall into this case.");
michael@0:         break;
michael@0:     }
michael@0:   }
michael@0: };
michael@0: 
michael@0: this.NSGetFactory = XPCOMUtils.generateNSGetFactory([InterAppMessagePort]);
michael@0: