/* ***** 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 Session Store component.
 *
 * The Initial Developer of the Original Code is
 * Mozilla Corporation
 * Portions created by the Initial Developer are Copyright (C) 2010
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Mark Finkle <mfinkle@mozilla.com>
 *
 * 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 ***** */

#include "nsISupports.idl"

interface nsIDOMWindow;
interface nsIDOMNode;

/**
 * nsISessionStore keeps track of the current browsing state.
 *
 * The nsISessionStore API operates mostly on browser windows and the browser
 * tabs contained in them.
 */

[scriptable, uuid(766a09c1-d21b-4bf8-9fe3-8b34b716251a)]
interface nsISessionStore : nsISupports
{
  /**
   * Get the current browsing state.
   * @returns a JSON string representing the session state.
   */
  AString getBrowserState();

  /**
   * Get the number of restore-able tabs for a browser window
   */
  unsigned long getClosedTabCount(in nsIDOMWindow aWindow);

  /**
   * Get closed tab data
   *
   * @param aWindow is the browser window for which to get closed tab data
   * @returns a JSON string representing the list of closed tabs.
   */
  AString getClosedTabData(in nsIDOMWindow aWindow);

  /**
   * @param aWindow is the browser window to reopen a closed tab in.
   * @param aIndex  is the index of the tab to be restored (FIFO ordered).
   * @returns a reference to the reopened tab.
   */
  nsIDOMNode undoCloseTab(in nsIDOMWindow aWindow, in unsigned long aIndex);

  /**
   * @param aWindow is the browser window associated with the closed tab.
   * @param aIndex  is the index of the closed tab to be removed (FIFO ordered).
   */
  nsIDOMNode forgetClosedTab(in nsIDOMWindow aWindow, in unsigned long aIndex);

  /**
   * @param aTab is the browser tab to get the value for.
   * @param aKey is the value's name.
   * 
   * @returns A string value or an empty string if none is set.
   */
  AString getTabValue(in nsIDOMNode aTab, in AString aKey);

  /**
   * @param aTab         is the browser tab to set the value for.
   * @param aKey         is the value's name.
   * @param aStringValue is the value itself (use JSON.stringify/parse before setting JS objects).
   */
  void setTabValue(in nsIDOMNode aTab, in AString aKey, in AString aStringValue);

  /**
   * @param aTab is the browser tab to get the value for.
   * @param aKey is the value's name.
   */
  void deleteTabValue(in nsIDOMNode aTab, in AString aKey);

  /**
   * @returns A boolean indicating we should restore previous browser session
   */
  boolean shouldRestore();

  /**
   * Restores the previous browser session using a fast, lightweight strategy
   * @param aBringToFront should a restored tab be brought to the foreground?
   */
  void restoreLastSession(in boolean aBringToFront);
};