/* -*- Mode: IDL; 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 "nsIArray.idl"
#include "nsISupports.idl"
#include "nsIDragSession.idl"
#include "nsIScriptableRegion.idl"
#include "nsIContentPolicy.idl"

interface nsIDOMNode;
interface nsIDOMDragEvent;
interface nsIDOMDataTransfer;
interface nsISelection;

%{C++
#include "mozilla/EventForwards.h"

namespace mozilla {
namespace dom {
class ContentParent;
} // namespace dom
} // namespace mozilla
%}

[ptr] native ContentParentPtr(mozilla::dom::ContentParent);
native EventMessage(mozilla::EventMessage);

[scriptable, uuid(ebd6b3a2-af16-43af-a698-3091a087dd62), builtinclass]
interface nsIDragService : nsISupports
{
  const long DRAGDROP_ACTION_NONE = 0;
  const long DRAGDROP_ACTION_COPY = 1;
  const long DRAGDROP_ACTION_MOVE = 2;
  const long DRAGDROP_ACTION_LINK = 4;
  const long DRAGDROP_ACTION_UNINITIALIZED = 64;

  /**
    * Starts a modal drag session with an array of transaferables.
    *
    * Note: This method is deprecated for non-native code.
    *
    * @param  aPrincipalURISpec - the URI of the triggering principal of the
    *            drag, or an empty string if it's from browser chrome or OS
    * @param  aTransferables - an array of transferables to be dragged
    * @param  aRegion - a region containing rectangles for cursor feedback, 
    *            in window coordinates.
    * @param  aActionType - specified which of copy/move/link are allowed
    * @param  aContentPolicyType - the contentPolicyType that will be
    *           passed to the loadInfo when creating a new channel
    *           (defaults to TYPE_OTHER)
    */
  void invokeDragSession (in nsIDOMNode aDOMNode,
                          in AUTF8String aPrincipalURISpec,
                          in nsIArray aTransferables, 
                          in nsIScriptableRegion aRegion,
                          in unsigned long aActionType,
                          [optional] in nsContentPolicyType aContentPolicyType);

  /**
   * Starts a modal drag session using an image. The first four arguments are
   * the same as invokeDragSession.
   *
   * Note: This method is deprecated for non-native code.
   *
   * A custom image may be specified using the aImage argument. If this is
   * supplied, the aImageX and aImageY arguments specify the offset within
   * the image where the cursor would be positioned. That is, when the image
   * is drawn, it is offset up and left the amount so that the cursor appears
   * at that location within the image.
   *
   * If aImage is null, aImageX and aImageY are not used and the image is instead
   * determined from the source node aDOMNode, and the offset calculated so that
   * the initial location for the image appears in the same screen position as
   * where the element is located. The node must be within a document.
   *
   * Currently, supported images are all DOM nodes. If this is an HTML <image> or
   * <canvas>, the drag image is taken from the image data. If the element is in
   * a document, it will be rendered at its displayed size, othewise, it will be
   * rendered at its real size. For other types of elements, the element is
   * rendered into an offscreen buffer in the same manner as it is currently
   * displayed. The document selection is hidden while drawing.
   *
   * The aDragEvent must be supplied as the current screen coordinates of the
   * event are needed to calculate the image location.
   */
  void invokeDragSessionWithImage(in nsIDOMNode aDOMNode,
                                  in AUTF8String aPrincipalURISpec,
                                  in nsIArray aTransferableArray,
                                  in nsIScriptableRegion aRegion,
                                  in unsigned long aActionType,
                                  in nsIDOMNode aImage,
                                  in long aImageX,
                                  in long aImageY,
                                  in nsIDOMDragEvent aDragEvent,
                                  in nsIDOMDataTransfer aDataTransfer);

  /**
   * Start a modal drag session using the selection as the drag image.
   * The aDragEvent must be supplied as the current screen coordinates of the
   * event are needed to calculate the image location.
   *
   * Note: This method is deprecated for non-native code.
   */
  void invokeDragSessionWithSelection(in nsISelection aSelection,
                                      in AUTF8String aPrincipalURISpec,
                                      in nsIArray aTransferableArray,
                                      in unsigned long aActionType,
                                      in nsIDOMDragEvent aDragEvent,
                                      in nsIDOMDataTransfer aDataTransfer);

  /**
    * Returns the current Drag Session  
    */
  nsIDragSession getCurrentSession ( ) ;

  /**
    * Tells the Drag Service to start a drag session. This is called when
    * an external drag occurs
    */
  void startDragSession ( ) ;

  /**
    * Tells the Drag Service to end a drag session. This is called when
    * an external drag occurs
    *
    * If aDoneDrag is true, the drag has finished, otherwise the drag has
    * just left the window.
    */
  void endDragSession(in boolean aDoneDrag,
                      [optional] in unsigned long aKeyModifiers);

  /**
   * Fire a drag event at the source of the drag
   */
  [noscript] void fireDragEventAtSource(in EventMessage aEventMessage,
                                        in unsigned long aKeyModifiers);

  /**
   * Increase/decrease dragging suppress level by one.
   * If level is greater than one, dragging is disabled.
   */
  void suppress();
  void unsuppress();

  /**
    * aX and aY are in LayoutDevice pixels.
    */
  [noscript] void dragMoved(in long aX, in long aY);

  [notxpcom, nostdcall] boolean maybeAddChildProcess(in ContentParentPtr aChild);
};


%{ C++

%}