<?xml version="1.0"?>
<!-- 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/.
-->

<bindings id="mailFolderBindings"
          xmlns="http://www.mozilla.org/xbl"
          xmlns:xbl="http://www.mozilla.org/xbl"
          xmlns:html="http://www.w3.org/1999/xhtml"
          xmlns:xul="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">

  <binding id="folder-menupopup"
           extends="chrome://global/content/bindings/popup.xml#popup">
    <implementation>
      <constructor><![CDATA[
        Components.utils.import("resource:///modules/FeedUtils.jsm", this);
        Components.utils.import("resource:///modules/folderUtils.jsm", this);
        Components.utils.import("resource:///modules/iteratorUtils.jsm", this);
        Components.utils.import("resource:///modules/mailServices.js", this);
        Components.utils.import("resource:///modules/MailUtils.js", this);
        Components.utils.import("resource:///modules/StringBundle.js", this);
        this._stringBundle = new this
            .StringBundle("chrome://messenger/locale/folderWidgets.properties");

        // Get the displayformat if set.
        if (this.parentNode && this.parentNode.localName == "menulist")
          this._displayformat = this.parentNode.getAttribute("displayformat");

        // Find out if we are in a wrapper (customize toolbars mode is active).
        let inWrapper = false;
        let node = this;
        while (node instanceof XULElement) {
          if (node.id.startsWith("wrapper-")) {
            inWrapper = true;
            break;
          }
          node = node.parentNode;
        }

        if (!inWrapper) {
          if (this.hasAttribute("original-width")) {
            // If we were in a wrapper before and have a width stored, restore it now.
            if (this.getAttribute("original-width") == "none")
              this.removeAttribute("width");
            else
              this.setAttribute("width", this.getAttribute("original-width"));

            this.removeAttribute("original-width");
          }

          // If we are a child of a menulist, and we aren't in a wrapper, we
          // need to build our content right away, otherwise the menulist
          // won't have proper sizing.
          if (this.parentNode && this.parentNode.localName == "menulist")
            this._ensureInitialized();
        } else {
          // But if we're in a wrapper, remove our children, because we're
          // getting re-created when the toolbar customization closes.
          this._teardown();

          // Store our current width and set a safe small width when we show
          // in a wrapper.
          if (!this.hasAttribute("original-width")) {
            this.setAttribute("original-width", this.hasAttribute("width") ?
                                                this.getAttribute("width") : "none");
            this.setAttribute("width", "100");
          }
        }
      ]]></constructor>
      <destructor><![CDATA[
        // Clean up when being destroyed.
        this._removeListener();
      ]]></destructor>
      <!--
         - Make sure we remove our listener when the window is being destroyed
         - or the widget teared down.
        -->
      <method name="_removeListener">
        <body><![CDATA[
          if (!this._initialized)
            return;

          this.MailServices.mailSession.RemoveFolderListener(this._listener);
        ]]></body>
      </method>

      <field name="_stringBundle">null</field>

      <!--
         - If non-null, the subFolders of this nsIMsgFolder will be used to
         - populate this menu.  If this is null, the menu will be populated
         - using the root-folders for all accounts
        -->
      <field name="_parentFolder">null</field>
      <property name="parentFolder"
                onget="return this._parentFolder;"
                onset="return this._parentFolder = val;"/>

      <!--
         - Various filtering modes can be used with this menu-binding.  To use
         - one of them, append the mode="foo" attribute to the element.  When
         - building the menu, we will then use this._filters[mode] as a filter
         - function to eliminate folders that should not be shown.
         -
         - Note that extensions should feel free to plug in here!
        -->
      <field name="_filters"><![CDATA[({
        // Returns true if messages can be filed in the folder
        filing: function filter_filing(aFolder) {
          if (!aFolder.server.canFileMessagesOnServer)
            return false;

          return (aFolder.canFileMessages || aFolder.hasSubFolders);
        },

        // Returns true if we can get mail for this folder. (usually this just
        // means the "root" fake folder)
        getMail: function filter_getMail(aFolder) {
          if (aFolder.isServer && aFolder.server.type != "none")
            return true;
          if (aFolder.server.type == "nntp" || aFolder.server.type == "rss")
            return true;
          return false;
        },

        // Returns true if we can add filters to this folder/account
        filters: function filter_filter(aFolder) {
          // We can always filter news
          if (aFolder.server.type == "nntp")
            return true;

          return aFolder.server.canHaveFilters;
        },

        subscribe: function filter_subscribe(aFolder) {
          return aFolder.canSubscribe;
        },

        newFolder: function filter_newFolder(aFolder) {
          return aFolder.canCreateSubfolders &&
                 aFolder.server.canCreateFoldersOnServer;
        },

        deferred: function filter_defered(aFolder) {
          return aFolder.server.canCreateFoldersOnServer &&
                 !aFolder.supportsOffline;
        },

        // Folders that can be searched.
        search: function filter_search(aFolder) {
          if (!aFolder.server.canSearchMessages ||
              aFolder.getFlag(Components.interfaces.nsMsgFolderFlags.Virtual))
            return false;
          return true;
        },

        // Folders that can subscribe feeds.
        feeds: function filter_feeds(aFolder) {
          if (aFolder.server.type != "rss" ||
              aFolder.getFlag(Components.interfaces.nsMsgFolderFlags.Trash) ||
              aFolder.getFlag(Components.interfaces.nsMsgFolderFlags.Virtual))
            return false;
          return true;
        },

        junk: function filter_junk(aFolder) {
          // Don't show servers (nntp & any others) which do not allow search or filing
          // I don't really understand why canSearchMessages is needed, but it was included in
          // earlier code, so I include it as well.
          if (!aFolder.server.canFileMessagesOnServer || !aFolder.server.canSearchMessages)
            return false;
          // show parents that might have usable subfolders, or usable folders
          return aFolder.hasSubFolders || aFolder.canFileMessages;
        }
      })]]></field>

      <!--
         - The maximum number of entries in the "Recent" menu
        -->
      <field name="_MAXRECENT">15</field>

      <!--
         - Our listener to let us know when folders change/appear/disappear so
         - we can know to rebuild ourselves.
        -->
      <field name="_listener">
          <![CDATA[({
        _menu: this,
        _clearMenu: function(aMenu) {
          if (aMenu._teardown)
            aMenu._teardown();
        },
        OnItemAdded: function act_add(aRDFParentItem, aItem) {
          if (!(aItem instanceof Components.interfaces.nsIMsgFolder))
            return;
          if (this._filterFunction && !this._filterFunction(aItem)) {
            return;
          }
          //xxx we can optimize this later
          //xxx I'm not quite sure why this isn't always a function
          if (this._menu._teardown)
            this._menu._teardown();
        },
  
        OnItemRemoved: function act_remove(aRDFParentItem, aItem) {
          if (!(aItem instanceof Components.interfaces.nsIMsgFolder))
            return;
          if (this._filterFunction && !this._filterFunction(aItem)) {
            return;
          }
          //xxx we can optimize this later
          if (this._menu._teardown)
            this._menu._teardown();
        },

        //xxx I stole this listener list from nsMsgFolderDatasource.cpp, but
        //    someone should really document what events are fired when, so that
        //    we make sure we're updating at the right times.
        OnItemPropertyChanged: function(aItem, aProperty, aOld, aNew) {},
        OnItemIntPropertyChanged: function(aItem, aProperty, aOld, aNew) {
          var child = this._getChildForItem(aItem);
          if (child)
            this._menu._setCssSelectors(child._folder, child);
        },
        OnItemBoolPropertyChanged: function(aItem, aProperty, aOld, aNew) {
          var child = this._getChildForItem(aItem);
          if (child)
            this._menu._setCssSelectors(child._folder, child);
        },
        OnItemUnicharPropertyChanged: function(aItem, aProperty, aOld, aNew) {
          var child = this._getChildForItem(aItem);
          if (child)
            this._menu._setCssSelectors(child._folder, child);
        },
        OnItemPropertyFlagChanged: function(aItem, aProperty, aOld, aNew) {},
        OnItemEvent: function(aFolder, aEvent) {
          if (aEvent.toString() == "MRMTimeChanged") {
            if (this._menu.getAttribute("showRecent") != "true" ||
                !this._menu.firstChild || !this._menu.firstChild.firstChild)
              return;
            // if this folder is already in the recent menu, return.
            if (this._getChildForItem(aFolder,
                                      this._menu.firstChild.firstChild))
              return;
          }
          // Special casing folder renames here, since they require more work
          // since sort-order may have changed.
          else if (aEvent.toString() == "RenameCompleted") {
            if (!this._getChildForItem(aFolder))
              return;
          }
          else
            return;
          // folder renamed, or new recent folder, so rebuild.
          setTimeout(this._clearMenu, 0, this._menu);
        },

        /**
         * Helper function to check and see whether we have a menuitem for this
         * particular nsIMsgFolder
         *
         * @param aItem  the nsIMsgFolder to check
         * @param aMenu  (optional) menu to look in, defaults to this._menu.
         * @returns      null if no child for that folder exists, otherwise the
         *               menuitem for that child
         */
        _getChildForItem: function act__itemIsChild(aItem, aMenu) {
          aMenu = aMenu || this._menu;
          if (!aMenu || !aMenu.childNodes)
            return null;

           if (!(aItem instanceof Components.interfaces.nsIMsgFolder))
             return null;
           for (let i = 0; i < aMenu.childNodes.length; i++) {
             let folder = aMenu.childNodes[i]._folder;
             if (folder && folder.URI == aItem.URI)
               return aMenu.childNodes[i];
           }
           return null;
        }
      })]]></field>

      <!-- 
         - True if we have already built our menu-items and are now just
         - listening for changes
        -->
      <field name="_initialized">false</field>

      <!--
         - Call this if you are unsure whether the menu-items have been built,
         - but know that they need to be built now if they haven't.
        -->
      <method name="_ensureInitialized">
        <body><![CDATA[
          if (this._initialized)
            return;

          // I really wish they'd just make this global...
          const Ci = Components.interfaces;

          let folders;

          // Figure out which folders to build.  If we don't have a parent, then
          // we assume we should build the top-level accounts. (Actually we
          // build the fake root folders for those accounts.)
          if (!this._parentFolder) {
            let accounts = this.allAccountsSorted(true);

            // Now generate our folder-list.  Note that we'll special case this
            // situation below, to avoid destroying the sort order we just made
            folders = accounts.map(function(acct) acct.incomingServer.rootFolder);
          } else {
            // If we do have a parent folder, then we just build based on those
            // subFolders for that parent.
            folders = this.toArray(this.fixIterator(this._parentFolder.subFolders,
                                                    Ci.nsIMsgFolder));
          }

          this._build(folders);

          // Lastly, we add a listener to get notified of changes in the folder
          // structure.
          this.MailServices.mailSession.AddFolderListener(this._listener,
                                                          Ci.nsIFolderListener.all);

          this._initialized = true;
        ]]></body>
      </method>

      <!--
         - Actually constructs the menu-items based on the folders given.
         -
         - @param aFolders  An array of nsIMsgFolders to use for building.
        -->
      <method name="_build">
        <parameter name="aFolders"/>
        <body><![CDATA[
          let folders;
          let excludeServers = [];
          let disableServers = [];

          // excludeServers attribute is a comma separated list of server keys.
          if (this.hasAttribute("excludeServers"))
            excludeServers = this.getAttribute("excludeServers").split(",");

          // disableServers attribute is a comma separated list of server keys.
          if (this.hasAttribute("disableServers"))
            disableServers = this.getAttribute("disableServers").split(",");

          // Extensions and other consumers can add to these modes too, see the
          // above note on the _filters field.
          var mode = this.getAttribute("mode");
          if (mode && mode != "") {
            var filterFunction = this._filters[mode];
            folders = aFolders.filter(filterFunction);
            this._listener._filterFunction = filterFunction;
          } else {
            folders = aFolders;
          }

          if (excludeServers.length > 0) {
            folders = folders.filter(function(aFolder) {
              return !(excludeServers.indexOf(aFolder.server.key) != -1); });
          }

          /* This code block will do the following: Add a menu item that refers
             back to the parent folder when there is a showFileHereLabel
             attribute or no mode attribute. However the code won't add such a
             menu item if one of the following conditions is met:
             (*) There is no parent folder
             (*) Folder is server and showAccountsFileHere is explicitly false
             (*) Current folder has a mode, the parent folder can be selected,
                 no messages can be filed into the parent folder (e.g. when the
                 parent folder is a news group or news server) and the folder
                 mode is not equal to newFolder

             The menu item will have the value of the fileHereLabel attribute as
             label or if the attribute does not exist the name of the parent
             folder instead.
          */
          let parent = this._parentFolder;
          if (parent && (this.getAttribute("showFileHereLabel") == "true" || !mode)) {
            let showAccountsFileHere = this.getAttribute("showAccountsFileHere");
            if ((!parent.isServer || showAccountsFileHere != "false") &&
                (!mode || mode == "newFolder" || parent.noSelect ||
                 parent.canFileMessages || showAccountsFileHere == "true")) {
              var menuitem = document.createElement("menuitem");
              menuitem._folder = this._parentFolder;
              menuitem.setAttribute("generated", "true");
              if (this.hasAttribute("fileHereLabel")) {
                menuitem.setAttribute("label", this.getAttribute("fileHereLabel"));
                menuitem.setAttribute("accesskey", this.getAttribute("fileHereAccessKey"));
              } else {
                menuitem.setAttribute("label", this._parentFolder.prettyName);
                menuitem.setAttribute("class", "folderMenuItem menuitem-iconic");
                this._setCssSelectors(this._parentFolder, menuitem);
              }
              // Eww. have to support some legacy code here...
              menuitem.setAttribute("id", this._parentFolder.URI);
              this.appendChild(menuitem);

              if (this._parentFolder.noSelect)
                menuitem.setAttribute("disabled", "true");

              var sep= document.createElement("menuseparator");
              sep.setAttribute("generated", "true");
              this.appendChild(sep);
            }
          }

          let globalInboxFolder = null;
          // See if this is the toplevel menu (usually with accounts).
          if (!this._parentFolder) {
            // Some menus want a "Recent" option, but that should only be on our
            // top-level menu
            if (this.getAttribute("showRecent") == "true")
              this._buildRecentMenu();
            // If we are showing the accounts for deferring, move Local Folders to the top.
            if (mode == "deferred") {
              globalInboxFolder = this.MailServices.accounts.localFoldersServer
                                                            .rootFolder;
              let localFoldersIndex = folders.indexOf(globalInboxFolder);
              if (localFoldersIndex != -1) {
                folders.splice(localFoldersIndex, 1);
                folders.unshift(globalInboxFolder);
              }
            }
            // If we're the root of the folder hierarchy, then we actually don't
            // want to sort the folders, but rather the accounts to which the
            // folders belong.  Since that sorting was already done, we don't need
            // to do anything for that case here.
          } else {
            // Sorts the list of folders. We give first priority to the sortKey
            // property if it is available, otherwise a case-insensitive
            // comparison of names.
            folders = folders.sort(function nameCompare(a, b) {
              return a.compareSortKeys(b);
            });
          }

          /* In some cases, the user wants to have a list of subfolders for only
           * some account types (or maybe all of them). So we use this to
           * determine what the user wanted.
           */
           var shouldExpand;
           var labels = null;
           if (this.getAttribute("expandFolders") == "true" ||
               !this.hasAttribute("expandFolders")) {
             shouldExpand = function (e) { return true; };
           } else if (this.getAttribute("expandFolders") == "false") {
             shouldExpand = function (e) { return false; };
           } else {
             /* We want a subfolder list for only some servers. We also may need
              * to create headers to select the servers. If so, then headlabels
              * is a comma-delimited list of labels corresponding to the server
              * types specified in expandFolders.
              */
             var types = this.getAttribute("expandFolders").split(/ *, */);
             // Set the labels. labels[type] = label
             if (this.hasAttribute("headlabels")) {
               var labelNames = this.getAttribute("headlabels").split(/ *, */);
               labels = {};
               // If the length isn't equal, don't give them any of the labels,
               // since any combination will probably be wrong.
               if (labelNames.length == types.length) {
                 for (var index in types)
                   labels[types[index]] = labelNames[index];
               }
             }
             shouldExpand = function (e) { return types.indexOf(e) != -1; };
           }

          // We need to call this, or hasSubFolders will always return false.
          // Remove this workaround when Bug 502900 is fixed.
          this.MailUtils.discoverFolders();

          for (let folder of folders) {
            let node;

            // If we're going to add subFolders, we need to make menus, not
            // menuitems.
            if (!folder.hasSubFolders || !shouldExpand(folder.server.type)) {
              node = document.createElement("menuitem");
              // Grumble, grumble, legacy code support
              node.setAttribute("id", folder.URI);
              node.setAttribute("class", "folderMenuItem menuitem-iconic");
              node.setAttribute("generated", "true");
              this.appendChild(node);
            } else {
              //xxx this is slightly problematic in that we haven't confirmed
              //    whether any of the subfolders will pass the filter
              node = document.createElement("menu");
              node.setAttribute("class", "folderMenuItem menu-iconic");
              node.setAttribute("generated", "true");
              this.appendChild(node);

              // Create the submenu
              // (We must use cloneNode here because on OS X the native menu
              // functionality and very sad limitations of XBL1 cause the bindings
              // to never get created for popup if we create a new element.  We
              // perform a shallow clone to avoid picking up any of our children.)
              var popup = this.cloneNode(false);
              popup._parentFolder = folder;
              popup.setAttribute("class", this.getAttribute("class"));
              popup.setAttribute("type", this.getAttribute("type"));
              if (this.hasAttribute("fileHereLabel"))
                popup.setAttribute("fileHereLabel",
                                   this.getAttribute("fileHereLabel"));
              popup.setAttribute("showFileHereLabel",
                                 this.getAttribute("showFileHereLabel"));
              popup.setAttribute("oncommand",
                                 this.getAttribute("oncommand"));
              popup.setAttribute("mode",
                                 this.getAttribute("mode"));
              if (this.hasAttribute("disableServers"))
                popup.setAttribute("disableServers",
                                   this.getAttribute("disableServers"));
              if (this.hasAttribute("position"))
                popup.setAttribute("position",
                                   this.getAttribute("position"));

              // If there are labels, add the labels now
              if (labels) {
                var serverNode = document.createElement("menuitem");
                serverNode.setAttribute("label", labels[folder.server.type]);
                serverNode._folder = folder;
                serverNode.setAttribute("generated", "true");
                popup.appendChild(serverNode);
                var sep = document.createElement("menuseparator");
                sep.setAttribute("generated", "true");
                popup.appendChild(sep);
              }

              popup.setAttribute("generated", "true");
              node.appendChild(popup);
            }

            if (disableServers.indexOf(folder.server.key) != -1)
              node.setAttribute("disabled", "true");

            node._folder = folder;
            let label = "";
            if (mode == "deferred" && folder.isServer &&
                folder.server.rootFolder == globalInboxFolder) {
              label = this._stringBundle.get("globalInbox", [folder.prettyName]);
            } else {
              label = folder.prettyName;
            }
            node.setAttribute("label", label);
            this._setCssSelectors(folder, node);
          }
        ]]></body>
      </method>

      <!--
         - Builds a submenu with all of the recently used folders in it, to
         - allow for easy access.
        -->
      <method name="_buildRecentMenu">
        <body><![CDATA[
          const Ci = Components.interfaces;

          // Iterate through all folders in all accounts, and find 15 (_MAXRECENT)
          // of most recently modified ones.
          let allFolders = this.toArray(
            this.fixIterator(this.MailServices.accounts.allFolders, Ci.nsIMsgFolder));

          allFolders = allFolders.filter(function (f) f.canFileMessages);

          let recentFolders = this.getMostRecentFolders(allFolders,
                                                        this._MAXRECENT,
                                                        "MRMTime");

          // Cache the pretty names so that they do not need to be fetched
          // _MAXRECENT^2 times later.
          recentFolders = recentFolders.map(
            function (f) { return { folder: f, name: f.prettyName } });

          // Because we're scanning across multiple accounts, we can end up with
          // several folders with the same name. Find those dupes.
          let dupeNames = new Set();
          for (let i = 0; i < recentFolders.length; i++) {
            for (let j = i + 1; j < recentFolders.length; j++) {
              if (recentFolders[i].name == recentFolders[j].name)
                dupeNames.add(recentFolders[i].name);
            }
          }

          for (let folderItem of recentFolders) {
            // If this folder name appears multiple times in the recent list,
            // append the server name to disambiguate.
            // TODO:
            // - maybe this could use verboseFolderFormat from messenger.properties
            //   instead of hardcoded " - ".
            // - disambiguate folders with same name in same account
            //   (in different subtrees).
            let label = folderItem.name;
            if (dupeNames.has(label))
              label += " - " + folderItem.folder.server.prettyName;

            folderItem.label = label;
          }

          // Make sure the entries are sorted alphabetically.
          recentFolders.sort((a, b) => this.folderNameCompare(a.label, b.label));

          // Now create the Recent folder and its children
          var menu = document.createElement("menu");
          menu.setAttribute("label", this.getAttribute("recentLabel"));
          menu.setAttribute("accesskey", this.getAttribute("recentAccessKey"));
          var popup = document.createElement("menupopup");
          popup.setAttribute("class", this.getAttribute("class"));
          popup.setAttribute("generated", "true");
          menu.appendChild(popup);

          // Create entries for each of the recent folders.
          for (let folderItem of recentFolders) {
            let node = document.createElement("menuitem");

            node.setAttribute("label", folderItem.label);
            node._folder = folderItem.folder;

            node.setAttribute("class", "folderMenuItem menuitem-iconic");
            this._setCssSelectors(folderItem.folder, node);
            node.setAttribute("generated", "true");
            popup.appendChild(node);
          }
          menu.setAttribute("generated", "true");
          this.appendChild(menu);
          if (!recentFolders.length)
            menu.setAttribute("disabled", "true");

          var sep = document.createElement("menuseparator");
          sep.setAttribute("generated", "true");
          this.appendChild(sep);
        ]]></body>
      </method>

      <!--
         - This function adds attributes on menu/menuitems to make it easier for
         - css to style them.
         -
         - @param aFolder    the folder that corresponds to the menu/menuitem
         - @param aMenuNode  the actual DOM node to set attributes on
        -->
      <method name="_setCssSelectors">
        <parameter name="aFolder"/>
        <parameter name="aMenuNode"/>
        <body><![CDATA[

          // First set the SpecialFolder attribute
          aMenuNode.setAttribute("SpecialFolder", this.getSpecialFolderString(aFolder));

          // Now set the biffState
          let biffStates = ["NewMail", "NoMail", "UnknownMail"];
          for each (let state in biffStates) {
            if (aFolder.biffState ==
                Components.interfaces.nsIMsgFolder["nsMsgBiffState_" + state]) {
              aMenuNode.setAttribute("BiffState", state);
              break;
            }
          }

          aMenuNode.setAttribute("IsServer", aFolder.isServer);
          aMenuNode.setAttribute("IsSecure", aFolder.server.isSecure);
          aMenuNode.setAttribute("ServerType", aFolder.server.type);
          aMenuNode.setAttribute("IsFeedFolder",
            (this.FeedUtils.getFeedUrlsInFolder(aFolder) ? true : false));
        ]]></body>
      </method>

      <!--
         - This function returns a formatted display name for a menulist
         - selected folder.  The desired format is set as the 'displayformat'
         - attribute of the folderpicker's <menulist>, one of:
         - 'name' (default) - Folder
         - 'verbose'        - Folder on Account
         - 'path'           - Account/Folder/Subfolder
         -
         - @param aFolder    the folder that corresponds to the menu/menuitem
         - @return string    display name
        -->
      <field name="_displayformat">null</field>
      <method name="getDisplayName">
        <parameter name="aFolder"/>
        <body><![CDATA[
          if (aFolder.isServer)
            return aFolder.prettyName;

          if (this._displayformat == "verbose")
            return this._stringBundle.getFormattedString("verboseFolderFormat",
                     [aFolder.prettyName, aFolder.server.prettyName]);

          if (this._displayformat == "path")
            return this.FeedUtils.getFolderPrettyPath(aFolder) || aFolder.name;

          return aFolder.name;
        ]]></body>
      </method>

      <!--
         - Makes a given folder selected.
         -
         - @param aFolder  the folder to select (if none, then Choose Folder)
         - @note  If aFolder is not in this popup, but is instead a descendant of
         -        a member of the popup, that ancestor will be selected.
         - @return  true if any usable folder was found, otherwise false.
        -->
      <method name="selectFolder">
        <parameter name="aFolder"/>
        <body><![CDATA[
          // Set the label of the menulist element as if aFolder had been selected.
          function setupParent(aFolder, aMenulist, aNoFolders) {
            let menupopup = aMenulist.menupopup;
            if (aFolder) {
              aMenulist.setAttribute("label", menupopup.getDisplayName(aFolder));
            } else {
              aMenulist.setAttribute("label", menupopup._stringBundle.getString(
                aNoFolders ? "noFolders" : "chooseFolder"));
            }
            aMenulist.setAttribute("value",
              aFolder ? aFolder.URI : "");
            aMenulist.setAttribute("IsServer",
              aFolder ? aFolder.isServer : false);
            aMenulist.setAttribute("IsSecure",
              aFolder ? aFolder.server.isSecure : false);
            aMenulist.setAttribute("ServerType",
              aFolder ? aFolder.server.type : "none");
            aMenulist.setAttribute("SpecialFolder",
              aFolder ? menupopup.getSpecialFolderString(aFolder) : "none");
            aMenulist.setAttribute("IsFeedFolder", Boolean(
              aFolder && menupopup.FeedUtils.getFeedUrlsInFolder(aFolder)));
            }

          let folder;
          if (aFolder) {
            for (let child of this.childNodes) {
              if (child && child._folder && !child.disabled &&
                  (child._folder.URI == aFolder.URI ||
                   (child.tagName == "menu" &&
                    child._folder.isAncestorOf(aFolder)))) {
                if (child._folder.URI == aFolder.URI)
                  this.parentNode.selectedItem = child;
                folder = aFolder;
                break;
              }
            }
          }

          // If the caller specified a folder to select and it was not
          // found, or if the caller didn't pass a folder (meaning a logical
          // and valid folder wasn't determined), don't blow up but reset
          // attributes and set a nice Choose Folder label so the user may
          // select a valid folder per the filter for this picker. If there are
          // no children, then no folder passed the filter; disable the menulist
          // as there's nothing to choose from.
          let noFolders;
          if (!this.childElementCount)
          {
            this.parentNode.setAttribute("disabled", true);
            noFolders = true;
          }
          else
          {
            this.parentNode.removeAttribute("disabled");
            noFolders = false;
          }

          setupParent(folder, this.parentNode, noFolders);
          return folder ? true : false;
        ]]></body>
      </method>

      <!--
         - Removes all menu-items for this popup, resets all fields, and
         - removes the listener.  This function is invoked when a change
         - that affects this menu is detected by our listener.
        -->
      <method name="_teardown">
        <body><![CDATA[
          for (let i = this.childNodes.length - 1; i >= 0; i--) {
            let child = this.childNodes[i];
            if (child.getAttribute("generated") != "true")
              continue;
            if ("_teardown" in child)
              child._teardown();
            child.remove();
          }

          this._removeListener();

          this._initialized = false;
        ]]></body>
      </method>
    </implementation>

    <handlers>
      <!--
         - In order to improve performance, we're not going to build any of the
         - menu until we're shown (unless we're the child of a menulist, see
         - note in the constructor).
         -
         - @note _ensureInitialized can be called repeatedly without issue, so
         -       don't worry about it here.
        -->
      <handler event="popupshowing" phase="capturing">
        this._ensureInitialized();
      </handler>
    </handlers>
  </binding>
</bindings>
