/* -*- Mode: C++; 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/. */

#include "nsISupports.idl"

interface nsIDOMElement;
interface nsILocalFile;

[scriptable, uuid(bb477da4-dddf-4106-a562-f06c85c7f9a8)]
interface nsIShellService : nsISupports
{
  /**
   * Determines whether or not Firefox is the "Default Browser."
   * This is simply whether or not Firefox is registered to handle 
   * http links. 
   * 
   * @param aStartupCheck true if this is the check being performed
   *                      by the first browser window at startup, 
   *                      false otherwise. 
   */
  boolean isDefaultBrowser(in boolean aStartupCheck);

  /**
   * Registers Firefox as the "Default Browser."
   *
   * @param aClaimAllTypes Register Firefox as the handler for 
   *                       additional protocols (ftp, chrome etc)
   *                       and web documents (.html, .xhtml etc).
   * @param aForAllUsers   Whether or not Firefox should attempt
   *                       to become the default browser for all
   *                       users on a multi-user system. 
   */
  void setDefaultBrowser(in boolean aClaimAllTypes, in boolean aForAllUsers);

  /** 
   * Used to determine whether or not to show a "Set Default Browser"
   * query dialog. This attribute is true if the application is starting
   * up and "browser.shell.checkDefaultBrowser" is true, otherwise it
   * is false.
   */
  attribute boolean shouldCheckDefaultBrowser;

  /**
   * Used to determine whether or not to offer "Set as desktop background"
   * functionality. Even if shell service is available it is not
   * guaranteed that it is able to set the background for every desktop
   * which is especially true for Linux with its many different desktop
   * environments.
   */
  readonly attribute boolean canSetDesktopBackground;

  /** 
   * Flags for positioning/sizing of the Desktop Background image.
   */
  const long BACKGROUND_TILE      = 1;
  const long BACKGROUND_STRETCH   = 2;
  const long BACKGROUND_CENTER    = 3;
  const long BACKGROUND_FILL      = 4;
  const long BACKGROUND_FIT       = 5;

    /**
     * Sets the desktop background image using either the HTML <IMG> 
     * element supplied or the background image of the element supplied.
     *
     * @param aImageElement Either a HTML <IMG> element or an element with
     *                      a background image from which to source the
     *                      background image. 
     * @param aPosition     How to place the image on the desktop
     */
  void setDesktopBackground(in nsIDOMElement aElement, in long aPosition);

  /**
   * Constants identifying applications that can be opened with
   * openApplication.
   */
  const long APPLICATION_MAIL        = 0;
  const long APPLICATION_NEWS        = 1;

  /**
   * Opens the application specified. If more than one application of the
   * given type is available on the system, the default or "preferred"
   * application is used. 
   */
  void openApplication(in long aApplication);

  /** 
   * The desktop background color, visible when no background image is 
   * used, or if the background image is centered and does not fill the 
   * entire screen. A rgb value, where (r << 16 | g << 8 | b)
   */
  attribute unsigned long desktopBackgroundColor;

  /**
   * Opens an application with a specific URI to load.
   * @param   application
   *          The application file (or bundle directory, on OS X)
   * @param   uri
   *          The uri to be loaded by the application
   */
  void openApplicationWithURI(in nsILocalFile aApplication, in ACString aURI);

  /**
   * The default system handler for web feeds
   */
  readonly attribute nsILocalFile defaultFeedReader;
};
