The Tor Browser / file revision

 /* 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/. */

 this.EXPORTED_SYMBOLS = ["PageMenu"];

 this.PageMenu = function PageMenu() {

 }

 PageMenu.prototype = {

   PAGEMENU_ATTR: "pagemenu",

   GENERATEDITEMID_ATTR: "generateditemid",

   popup: null,

   builder: null,

   maybeBuildAndAttachMenu: function(aTarget, aPopup) {

     var pageMenu = null;

     var target = aTarget;

     while (target) {

       var contextMenu = target.contextMenu;

       if (contextMenu) {

         pageMenu = contextMenu;

         break;

       }

       target = target.parentNode;

     }

     if (!pageMenu) {

       return false;

     }

     var insertionPoint = this.getInsertionPoint(aPopup);

     if (!insertionPoint) {

       return false;

     }

     pageMenu.QueryInterface(Components.interfaces.nsIHTMLMenu);

     pageMenu.sendShowEvent();

     // the show event is not cancelable, so no need to check a result here

     var fragment = aPopup.ownerDocument.createDocumentFragment();

     var builder = pageMenu.createBuilder();

     if (!builder) {

       return false;

     }

     builder.QueryInterface(Components.interfaces.nsIXULContextMenuBuilder);

     builder.init(fragment, this.GENERATEDITEMID_ATTR);

     pageMenu.build(builder);

     var pos = insertionPoint.getAttribute(this.PAGEMENU_ATTR);

     if (pos == "start") {

       insertionPoint.insertBefore(fragment,

                                   insertionPoint.firstChild);

     } else {

       insertionPoint.appendChild(fragment);

     }

     this.builder = builder;

     this.popup = aPopup;

     this.popup.addEventListener("command", this);

     this.popup.addEventListener("popuphidden", this);

     return true;

   },

   handleEvent: function(event) {

     var type = event.type;

     var target = event.target;

     if (type == "command" && target.hasAttribute(this.GENERATEDITEMID_ATTR)) {

       this.builder.click(target.getAttribute(this.GENERATEDITEMID_ATTR));

     } else if (type == "popuphidden" && this.popup == target) {

       this.removeGeneratedContent(this.popup);

       this.popup.removeEventListener("popuphidden", this);

       this.popup.removeEventListener("command", this);

       this.popup = null;

       this.builder = null;

     }

   },

   getImmediateChild: function(element, tag) {

     var child = element.firstChild;

     while (child) {

       if (child.localName == tag) {

         return child;

       }

       child = child.nextSibling;

     }

     return null;

   },

   getInsertionPoint: function(aPopup) {

     if (aPopup.hasAttribute(this.PAGEMENU_ATTR))

       return aPopup;

     var element = aPopup.firstChild;

     while (element) {

       if (element.localName == "menu") {

         var popup = this.getImmediateChild(element, "menupopup");

         if (popup) {

           var result = this.getInsertionPoint(popup);

           if (result) {

             return result;

           }

         }

       }

       element = element.nextSibling;

     }

     return null;

   },

   removeGeneratedContent: function(aPopup) {

     var ungenerated = [];

     ungenerated.push(aPopup);

     var count;

     while (0 != (count = ungenerated.length)) {

       var last = count - 1;

       var element = ungenerated[last];

       ungenerated.splice(last, 1);

       var i = element.childNodes.length;

       while (i-- > 0) {

         var child = element.childNodes[i];

         if (!child.hasAttribute(this.GENERATEDITEMID_ATTR)) {

           ungenerated.push(child);

           continue;

         }

         element.removeChild(child);

       }

     }

   }

 }