# -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-# ***** BEGIN LICENSE BLOCK *****# Version: MPL 1.1/GPL 2.0/LGPL 2.1## The contents of this file are subject to the Mozilla Public License Version# 1.1 (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.mozilla.org/MPL/## Software distributed under the License is distributed on an "AS IS" basis,# WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License# for the specific language governing rights and limitations under the# License.## The Original Code is the RSS Parsing Engine## The Initial Developer of the Original Code is# The Mozilla Foundation.# Portions created by the Initial Developer are Copyright (C) 2004# the Initial Developer. All Rights Reserved.## Contributor(s):## Alternatively, the contents of this file may be used under the terms of# either the GNU General Public License Version 2 or later (the "GPL"), or# the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),# in which case the provisions of the GPL or the LGPL are applicable instead# of those above. If you wish to allow use of your version of this file only# under the terms of either the GPL or the LGPL, and not to allow others to# use your version of this file under the terms of the MPL, indicate your# decision by deleting the provisions above and replace them with the notice# and other provisions required by the GPL or the LGPL. If you do not delete# the provisions above, a recipient may use your version of this file under# the terms of any one of the MPL, the GPL or the LGPL.## ***** END LICENSE BLOCK ***** */// error codes used to inform the consumer about attempts to download a feedconst kNewsBlogSuccess = 0;const kNewsBlogInvalidFeed = 1; // usually means there was an error trying to parse the feed...const kNewsBlogRequestFailure = 2; // generic networking failure when trying to download the feed.const kNewsBlogFeedIsBusy = 3;const kNewsBlogNoNewItems = 4; // there are no new articles for this feed// Cache for all of the feeds currently being downloaded, indexed by URL, so the load event listener// can access the Feed objects after it finishes downloading the feed.var FeedCache = {  mFeeds: new Array(),  putFeed: function (aFeed)  {    this.mFeeds[this.normalizeHost(aFeed.url)] = aFeed;  },  getFeed: function (aUrl)  {    return this.mFeeds[this.normalizeHost(aUrl)];  },  removeFeed: function (aUrl)  {    delete this.mFeeds[this.normalizeHost(aUrl)];  },  normalizeHost: function (aUrl)  {    var ioService = Components.classes["@mozilla.org/network/io-service;1"].                    getService(Components.interfaces.nsIIOService);    var normalizedUrl = ioService.newURI(aUrl, null, null);    normalizedUrl.host = normalizedUrl.host.toLowerCase();    return normalizedUrl.spec;  }};function Feed(aResource, aRSSServer) {  this.resource = aResource.QueryInterface(Components.interfaces.nsIRDFResource);  this.server = aRSSServer;}Feed.prototype = {  description: null,  author: null,  request: null,  server: null,  downloadCallback: null,  resource: null,  items: new Array(),  mFolder: null,  get folder()  {    if (!this.mFolder)    {      try       {        this.mFolder = this.server.rootMsgFolder.getChildNamed(this.name);      } catch (ex) {}    }    return this.mFolder;  },  set folder (aFolder)   {    this.mFolder = aFolder;  },  get name()  {    var name = this.title || this.description || this.url;    if (!name)      throw("couldn't compute feed name, as feed has no title, description, or URL.");    // Make sure the feed name doesn't have any line breaks, since we're going    // to use it as the name of the folder in the filesystem.  This may not    // be necessary, since Mozilla's mail code seems to handle other forbidden    // characters in filenames and can probably handle these as well.    name = name.replace(/[\n\r\t]+/g, " ");    // Make sure the feed doesn't end in a period to work around bug 117840.    name = name.replace(/\.+$/, "");    return name;  },  download: function(aParseItems, aCallback)   {     this.downloadCallback = aCallback; // may be null     // Whether or not to parse items when downloading and parsing the feed.    // Defaults to true, but setting to false is useful for obtaining    // just the title of the feed when the user subscribes to it.    this.parseItems = aParseItems == null ? true : aParseItems ? true : false;    // Before we do anything...make sure the url is an http url. This is just a sanity check    // so we don't try opening mailto urls, imap urls, etc. that the user may have tried to subscribe to     // as an rss feed..    var uri = Components.classes["@mozilla.org/network/standard-url;1"].                        createInstance(Components.interfaces.nsIURI);    uri.spec = this.url;    if (!(uri.schemeIs("http") || uri.schemeIs("https")))      return this.onParseError(this); // simulate an invalid feed error    // Before we try to download the feed, make sure we aren't already processing the feed    // by looking up the url in our feed cache    if (FeedCache.getFeed(this.url))    {      if (this.downloadCallback)        this.downloadCallback.downloaded(this, kNewsBlogFeedIsBusy);      return ; // don't do anything, the feed is already in use    }    this.request = Components.classes["@mozilla.org/xmlextras/xmlhttprequest;1"]                   .createInstance(Components.interfaces.nsIXMLHttpRequest);    this.request.onprogress = this.onProgress; // must be set before calling .open    this.request.open("GET", this.url, true);    var lastModified = this.lastModified;    if (lastModified)      this.request.setRequestHeader("If-Modified-Since", lastModified);    this.request.overrideMimeType("text/xml");    this.request.onload = this.onDownloaded;    this.request.onerror = this.onDownloadError;    FeedCache.putFeed(this);    this.request.send(null);  },   onDownloaded: function(aEvent)   {    var request = aEvent.target;    var url = request.channel.originalURI.spec;    debug(url + " downloaded");    var feed = FeedCache.getFeed(url);    if (!feed)      throw("error after downloading " + url + ": couldn't retrieve feed from request");    // if the request has a Last-Modified header on it, then go ahead and remember    // that as a property on the feed so we can use it when making future requests.        var lastModifiedHeader = request.getResponseHeader('Last-Modified');    if (lastModifiedHeader)      this.lastModified = lastModifiedHeader;    feed.parse(); // parse will asynchronously call the download callback when it is done  },     onProgress: function(aEvent)   {    var request = aEvent.target;    var url = request.channel.originalURI.spec;    var feed = FeedCache.getFeed(url);    if (feed.downloadCallback)      feed.downloadCallback.onProgress(feed, aEvent.position, aEvent.totalSize);  },  onDownloadError: function(aEvent)   {    var request = aEvent.target;    var url = request.channel.originalURI.spec;    var feed = FeedCache.getFeed(url);    if (feed.downloadCallback)     {      // if the http status code is a 304, then the feed has not been modified since we last downloaded it.      var error = kNewsBlogRequestFailure;      try      {        if (request.status == 304)          error = kNewsBlogNoNewItems;      } catch (ex) {}      feed.downloadCallback.downloaded(feed, error);    }        FeedCache.removeFeed(url);  },  onParseError: function(aFeed)   {    if (aFeed && aFeed.downloadCallback)    {      if (aFeed.downloadCallback)        aFeed.downloadCallback.downloaded(aFeed, aFeed.request && aFeed.request.status == 304 ? kNewsBlogNoNewItems : kNewsBlogInvalidFeed);      FeedCache.removeFeed(aFeed.url);    }  },  get url()  {    var ds = getSubscriptionsDS(this.server);    var url = ds.GetTarget(this.resource, DC_IDENTIFIER, true);    if (url)