/* -*- 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 nsIInputStream;
interface imgIContainer;

[scriptable, uuid(1f19a2ce-cf5c-4a6b-8ba7-63785b45053f)]
interface imgITools : nsISupports
{
    /**
     * decodeImageData
     * Caller provides an input stream and mimetype. We read from the stream
     * and decompress it (according to the specified mime type) and return
     * the resulting imgIContainer. (If the caller already has a container,
     * it can be provided as input to be reused).
     *
     * @param aStream
     *        An input stream for an encoded image file.
     * @param aMimeType
     *        Type of image in the stream.
     * @param aContainer
     *        An imgIContainer holding the decoded image. Specify |null| when
     *        calling to have one created, otherwise specify a container to
     *        be used. It is an error to pass an already-initialized container
     *        as aContainer.
     */
    void decodeImageData(in nsIInputStream aStream,
                         in ACString aMimeType,
                         inout imgIContainer aContainer);

    /**
     * encodeImage
     * Caller provides an image container, and the mime type it should be
     * encoded to. We return an input stream for the encoded image data.
     *
     * @param aContainer
     *        An image container.
     * @param aMimeType
     *        Type of encoded image desired (eg "image/png").
     * @param outputOptions
     *        Encoder-specific output options.
     */
    nsIInputStream encodeImage(in imgIContainer aContainer,
                               in ACString aMimeType,
                               [optional] in AString outputOptions);

    /**
     * encodeScaledImage
     * Caller provides an image container, and the mime type it should be
     * encoded to. We return an input stream for the encoded image data.
     * The encoded image is scaled to the specified dimensions.
     *
     * @param aContainer
     *        An image container.
     * @param aMimeType
     *        Type of encoded image desired (eg "image/png").
     * @param aWidth, aHeight
     *        The size (in pixels) desired for the resulting image.
     * @param outputOptions
     *        Encoder-specific output options.
     */
    nsIInputStream encodeScaledImage(in imgIContainer aContainer,
                                     in ACString aMimeType,
                                     in long aWidth,
                                     in long aHeight,
                                     [optional] in AString outputOptions);
};
