/* -*- 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 "nsIDOMHTMLElement.idl"

%{C++
// for jsval
#include "jsapi.h"
%}

/**
 * The nsIDOMHTMLCanvasElement interface is the interface to a HTML
 * <canvas> element.
 *
 * For more information on this interface, please see
 * http://www.whatwg.org/specs/web-apps/current-work/#graphics
 *
 * @status UNDER_DEVELOPMENT
 */

interface nsIDOMFile;
interface nsIVariant;
interface nsIInputStreamCallback;

[scriptable, uuid(5929542B-C68E-48AB-84F9-D9642DA39720)]
interface nsIDOMHTMLCanvasElement : nsIDOMHTMLElement
{
  attribute unsigned long width;
  attribute unsigned long height;
  attribute boolean mozOpaque;

  nsISupports getContext(in DOMString contextId,
                         [optional] in jsval contextOptions);


  // Valid calls are:
  //  toDataURL();              -- defaults to image/png
  //  toDataURL(type);          -- uses given type
  //  toDataURL(type, params);  -- uses given type, and any valid parameters
  [optional_argc] DOMString toDataURL([optional] in DOMString type,
                                      [optional] in nsIVariant params);

  // Valid calls are
  // mozGetAsFile(name);              -- defaults to image/png
  // mozGetAsFile(name, type);        -- uses given type
  [optional_argc] nsIDOMFile mozGetAsFile(in DOMString name,
                                          [optional] in DOMString type);

  // A Mozilla-only extension to get a canvas context backed by double-buffered
  // shared memory. Only privileged callers can call this.
  nsISupports MozGetIPCContext(in DOMString contextId);

  // A Mozilla-only extension that returns the canvas' image data as a data
  // stream in the desired image format.
  void mozFetchAsStream(in nsIInputStreamCallback callback,
                                        [optional] in DOMString type);
};