/*

* Copyright (c) 2005-2007 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description:   Data sink API for chunked receiving of large messages

*

*/

#ifndef MMMSCODECDATASINK_H

#define MMMSCODECDATASINK_H

#include <e32base.h>

/**

 *  Defines the interface for chunked data supply

 *

 *  When MMS messages are sent in chunks this provides the interface

 *  that can be called to get next encoded data chunk

 *

 *  @since v3.1

 */

class MMmsCodecDataSink

    {

public:

    /**

     * Gives the next data part to be decoded.

     * Decoding is synchronous. When the code returns, data can be released.

     *

     * @since v3.1

     * @param aBuffer flat buffer containing the data to be decoded.

     * @param aPosition start of data to be decoded.

     *     Decoding will start from aPosition.

     *     At return aPosition will point to the data that has not been

     *     decoded yet (in case data ends with an incomplete header) or

     *     past the end of data if everything has been decoded.

     *     The caller can discard the beginning of data up to aPosition.

     *     If there is data left in the buffer it must be shifted to the

     *     beginning of buffer and new data appended to the end to allow

     *     an incomplete header to be decoded at next round.

     * @param aLastChunk ETrue if the data chunk in the buffer is the last one.

     * @return error code, KErrNone if decoding succeeds

     *     If returns some other error, transaction must be cancelled.

     */

    virtual TInt NextDataPart(

        CBufFlat& aBuffer,

        TInt& aPosition,

        TBool aLastDataChunk ) = 0;

    /**

     * Release data sink and free any resources

     * This function must be called after last data chunk has been processed

     * This function must also be called if the process is terminated by an error

     *

     * @since v3.1

     */

    virtual void RelaseDataSink() = 0;    

    /**

     * Reset data sink.

     * Delete all attachments from current message.

     * Reset MMS headers

     * Start message decoding from the beginning

     * 

     * This function must be called if transaction is interrupted and restarted

     *

     * @since v3.1

     */

    virtual void ResetDataSink() = 0;    

    };

#endif // MMMSCODECDATASINK_H