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 /* -*- Mode: javascript; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

 /* 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/. */

 /*

  * The behavior implemented by gDownloadLastDir is documented here.

  *

  * In normal browsing sessions, gDownloadLastDir uses the browser.download.lastDir

  * preference to store the last used download directory. The first time the user

  * switches into the private browsing mode, the last download directory is

  * preserved to the pref value, but if the user switches to another directory

  * during the private browsing mode, that directory is not stored in the pref,

  * and will be merely kept in memory.  When leaving the private browsing mode,

  * this in-memory value will be discarded, and the last download directory

  * will be reverted to the pref value.

  *

  * Both the pref and the in-memory value will be cleared when clearing the

  * browsing history.  This effectively changes the last download directory

  * to the default download directory on each platform.

  *

  * If passed a URI, the last used directory is also stored with that URI in the

  * content preferences database. This can be disabled by setting the pref

  * browser.download.lastDir.savePerSite to false.

  */

 const LAST_DIR_PREF = "browser.download.lastDir";

 const SAVE_PER_SITE_PREF = LAST_DIR_PREF + ".savePerSite";

 const nsIFile = Components.interfaces.nsIFile;

 this.EXPORTED_SYMBOLS = [ "DownloadLastDir" ];

 Components.utils.import("resource://gre/modules/Services.jsm");

 Components.utils.import("resource://gre/modules/PrivateBrowsingUtils.jsm");

 let observer = {

   QueryInterface: function (aIID) {

     if (aIID.equals(Components.interfaces.nsIObserver) ||

         aIID.equals(Components.interfaces.nsISupports) ||

         aIID.equals(Components.interfaces.nsISupportsWeakReference))

       return this;

     throw Components.results.NS_NOINTERFACE;

   },

   observe: function (aSubject, aTopic, aData) {

     switch (aTopic) {

       case "last-pb-context-exited":

         gDownloadLastDirFile = null;

         break;

       case "browser:purge-session-history":

         gDownloadLastDirFile = null;

         if (Services.prefs.prefHasUserValue(LAST_DIR_PREF))

           Services.prefs.clearUserPref(LAST_DIR_PREF);

         // Ensure that purging session history causes both the session-only PB cache

         // and persistent prefs to be cleared.

         let cps2 = Components.classes["@mozilla.org/content-pref/service;1"].

                      getService(Components.interfaces.nsIContentPrefService2);

         cps2.removeByName(LAST_DIR_PREF, {usePrivateBrowsing: false});

         cps2.removeByName(LAST_DIR_PREF, {usePrivateBrowsing: true});

         break;

     }

   }

 };

 let os = Components.classes["@mozilla.org/observer-service;1"]

                    .getService(Components.interfaces.nsIObserverService);

 os.addObserver(observer, "last-pb-context-exited", true);

 os.addObserver(observer, "browser:purge-session-history", true);

 function readLastDirPref() {

   try {

     return Services.prefs.getComplexValue(LAST_DIR_PREF, nsIFile);

   }

   catch (e) {

     return null;

   }

 }

 function isContentPrefEnabled() {

   try {

     return Services.prefs.getBoolPref(SAVE_PER_SITE_PREF);

   }

   catch (e) {

     return true;

   }

 }

 let gDownloadLastDirFile = readLastDirPref();

 this.DownloadLastDir = function DownloadLastDir(aWindow) {

   this.window = aWindow;

 }

 DownloadLastDir.prototype = {

   isPrivate: function DownloadLastDir_isPrivate() {

     return PrivateBrowsingUtils.isWindowPrivate(this.window);

   },

   // compat shims

   get file() this._getLastFile(),

   set file(val) { this.setFile(null, val); },

   cleanupPrivateFile: function () {

     gDownloadLastDirFile = null;

   },

   // This function is now deprecated as it uses the sync nsIContentPrefService

   // interface. New consumers should use the getFileAsync function.

   getFile: function (aURI) {

     let Deprecated = Components.utils.import("resource://gre/modules/Deprecated.jsm", {}).Deprecated;

     Deprecated.warning("DownloadLastDir.getFile is deprecated. Please use getFileAsync instead.",

                        "https://developer.mozilla.org/en-US/docs/Mozilla/JavaScript_code_modules/DownloadLastDir.jsm",

                        Components.stack.caller);

     if (aURI && isContentPrefEnabled()) {

       let loadContext = this.window

                             .QueryInterface(Components.interfaces.nsIInterfaceRequestor)

                             .getInterface(Components.interfaces.nsIWebNavigation)

                             .QueryInterface(Components.interfaces.nsILoadContext);

       let lastDir = Services.contentPrefs.getPref(aURI, LAST_DIR_PREF, loadContext);

       if (lastDir) {

         var lastDirFile = Components.classes["@mozilla.org/file/local;1"]

                                     .createInstance(Components.interfaces.nsIFile);

         lastDirFile.initWithPath(lastDir);

         return lastDirFile;

       }

     }

     return this._getLastFile();

   },

   _getLastFile: function () {

     if (gDownloadLastDirFile && !gDownloadLastDirFile.exists())

       gDownloadLastDirFile = null;

     if (this.isPrivate()) {

       if (!gDownloadLastDirFile)

         gDownloadLastDirFile = readLastDirPref();

       return gDownloadLastDirFile;

     }

     return readLastDirPref();

   },

   getFileAsync: function(aURI, aCallback) {

     let plainPrefFile = this._getLastFile();

     if (!aURI || !isContentPrefEnabled()) {

       Services.tm.mainThread.dispatch(function() aCallback(plainPrefFile),

                                       Components.interfaces.nsIThread.DISPATCH_NORMAL);

       return;

     }

     let uri = aURI instanceof Components.interfaces.nsIURI ? aURI.spec : aURI;

     let cps2 = Components.classes["@mozilla.org/content-pref/service;1"]

                          .getService(Components.interfaces.nsIContentPrefService2);

     let loadContext = this.window

                           .QueryInterface(Components.interfaces.nsIInterfaceRequestor)

                           .getInterface(Components.interfaces.nsIWebNavigation)

                           .QueryInterface(Components.interfaces.nsILoadContext);

     let result = null;

     cps2.getByDomainAndName(uri, LAST_DIR_PREF, loadContext, {

       handleResult: function(aResult) result = aResult,

       handleCompletion: function(aReason) {

         let file = plainPrefFile;

         if (aReason == Components.interfaces.nsIContentPrefCallback2.COMPLETE_OK &&

            result instanceof Components.interfaces.nsIContentPref) {

           file = Components.classes["@mozilla.org/file/local;1"]

                            .createInstance(Components.interfaces.nsIFile);

           file.initWithPath(result.value);

         }

         aCallback(file);

       }

     });

   },

   setFile: function (aURI, aFile) {

     if (aURI && isContentPrefEnabled()) {

       let uri = aURI instanceof Components.interfaces.nsIURI ? aURI.spec : aURI;

       let cps2 = Components.classes["@mozilla.org/content-pref/service;1"]

                            .getService(Components.interfaces.nsIContentPrefService2);

       let loadContext = this.window

                             .QueryInterface(Components.interfaces.nsIInterfaceRequestor)

                             .getInterface(Components.interfaces.nsIWebNavigation)

                             .QueryInterface(Components.interfaces.nsILoadContext);

       if (aFile instanceof Components.interfaces.nsIFile)

         cps2.set(uri, LAST_DIR_PREF, aFile.path, loadContext);

       else

         cps2.removeByDomainAndName(uri, LAST_DIR_PREF, loadContext);

     }

     if (this.isPrivate()) {

       if (aFile instanceof Components.interfaces.nsIFile)

         gDownloadLastDirFile = aFile.clone();

       else

         gDownloadLastDirFile = null;

     } else {

       if (aFile instanceof Components.interfaces.nsIFile)

         Services.prefs.setComplexValue(LAST_DIR_PREF, nsIFile, aFile);

       else if (Services.prefs.prefHasUserValue(LAST_DIR_PREF))

         Services.prefs.clearUserPref(LAST_DIR_PREF);

     }

   }

 };