/* 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/. */

#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(da9ffc70-d444-47d4-b4ab-df3fb0fd24d0)]
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 JS array of closed tabs.
   */
  jsval getClosedTabs(in nsIDOMWindow aWindow);

  /**
   * @param aWindow is the browser window to reopen a closed tab in.
   * @param aCloseTabData is the data of the tab to be restored.
   * @returns a reference to the reopened tab.
   */
  nsIDOMNode undoCloseTab(in nsIDOMWindow aWindow, in jsval aCloseTabData);

  /**
   * @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);

  /**
   * Whether the "Undo close tab" message should be shown or not after a tab has been closed.
   */
 readonly attribute boolean canUndoLastCloseTab;

  /**
   * @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 jsval 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 jsval 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 jsval aTab, in AString aKey);

  /**
   * Restores the passed tab if it is currently zombified and set to be delay loaded.
   * @param aTab The browser tab to be restored.
   */
  void restoreZombieTab(in jsval aTab);

  /**
   * Removes a window from the current session history. Data from this window
   * won't be saved when its closed.
   * @param aWindow The window to remove
   */
  void removeWindow(in nsIDOMWindow aWindow);

  /**
   * Set the load state of the session store. Use only for testing.
   * @param aState The target load state.
   */
  void setLoadState(in long aState);
};
