/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 *
 * ***** 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 mozilla.org code.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 2001
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Stuart Parmenter <pavlov@netscape.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 imgIDecoderObserver;
interface imgIRequest;

interface nsIChannel;
interface nsILoadGroup;
interface nsIStreamListener;
interface nsIURI;

interface nsISimpleEnumerator;

#include "nsIRequest.idl" // for nsLoadFlags

/**
 * imgILoader interface
 *
 * @author Stuart Parmenter <pavlov@netscape.com>
 * @version 0.3
 * @see imagelib2
 */
[scriptable, uuid(a32826ff-9e56-4425-a811-97a8dba64ff5)]
interface imgILoader : nsISupports
{
  /**
   * Start the load and decode of an image.
   * @param aURI the URI to load
   * @param aInitialDocumentURI the URI that 'initiated' the load -- used for 3rd party cookie blocking
   * @param aReferrerURI the 'referring' URI
   * @param aLoadGroup Loadgroup to put the image load into
   * @param aObserver the observer
   * @param aCX some random data
   * @param aLoadFlags Load flags for the request
   * @param aCacheKey cache key to use for a load if the original
   *                  image came from a request that had post data
   * @param aRequest A newly created, unused imgIRequest object or NULL for one to
                     be created for you.


   * libpr0n does NOT keep a strong ref to the observer; this prevents
   * reference cycles.  This means that callers of loadImage should
   * make sure to Cancel() the resulting request before the observer
   * goes away.
   */
  imgIRequest loadImage(in nsIURI aURI,
                        in nsIURI aInitialDocumentURL,
                        in nsIURI aReferrerURI,
                        in nsILoadGroup aLoadGroup,
                        in imgIDecoderObserver aObserver,
                        in nsISupports aCX,
                        in nsLoadFlags aLoadFlags,
                        in nsISupports cacheKey,
                        in imgIRequest aRequest);

  /**
   * Start the load and decode of an image.
   * @param aChannel the channel to load the image from.  This must
   *                 already be opened before ths method is called, and there
   *                 must have been no OnDataAvailable calls for it yet.   
   * @param aObserver the observer
   * @param cx some random data
   * @param aListener [out]
   *        A listener that should receive the data. Can be null, in which
   *        case imagelib has found a cached image and is not interested in
   *        the data. The caller needs not cancel the channel in this case.
   *
   * libpr0n does NOT keep a strong ref to the observer; this prevents
   * reference cycles.  This means that callers of loadImageWithChannel should
   * make sure to Cancel() the resulting request before the observer goes away.
   */
  imgIRequest loadImageWithChannel(in nsIChannel aChannel, in imgIDecoderObserver aObserver, in nsISupports cx, out nsIStreamListener aListener);

  /**
   * Checks if a decoder for the an image with the given mime type is available
   * @param mimeType The type to find a decoder for
   * @return true if a decoder is available, false otherwise
   */
  boolean supportImageWithMimeType(in string mimeType);
};
