/*

* Copyright (c) 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:    Observer class that the client must implement to receive notifications about

*                incoming and outgoing messages. Allows observer to observe and 

*                make modifications to offered messages.

*

*/

#ifndef M_MNCMMESSAGEOBSERVER_H

#define M_MNCMMESSAGEOBSERVER_H

#include <e32base.h>

/**

 *  Observer class that the client must implement to receive notifications about

 *  incoming and outgoing messages. Allows observer to observe and 

 *  make modifications to offered messages

 *

 *  @lib connectionmux.lib

 *  @since S60 v3.2

 */

class MNcmMessageObserver

    {

public:

    /**

     * Called by Connection Multiplexer when incoming message is found.

     * Allows connection observer to observe and make modifications to found

     * message by offering an own copy of content with modification(s).

     *

     * @since   S60 v3.2

     * @param   aStreamId           The ID identifying stream

     * @param   aMessage            Message is a reference to constant message

     * @param   aLocalAddr          A stream local address.

     * @param   aFromAddr           A remote source address. ( From socket )

     * @param   aPeerRemoteAddr     A peer remote address.

     * @return  Pointer to a heap descriptor with new content for message,

     *          otherwise NULL is returned. Ownership of the heap descriptor is

     *          transferred to connection multiplexer ( from observer ).

     */

    virtual HBufC8* IncomingMessageNotify( TUint aStreamId,

        const TDesC8& aMessage, const TInetAddr& aLocalAddr,

        const TInetAddr& aFromAddr, TInetAddr& aPeerRemoteAddr ) = 0;

    /**

     * Called by Connection Multiplexer when outgoing message is found.

     * Allows connection observer to observe and make modifications to found

     * message by offering an own copy of content with modification(s).

     *

     * @since S60 v3.2

     * @param aStreamId             The ID identifying stream

     * @param aConnectionId         The ID identifying connection

     * @param aDestinationAddress   Destination address where the packet

     *                              is being sent to.   

     * @param aMessage              Message is a reference to constant message

     *                              which was found

     * @return pointer to a heap descriptor with new content for message,

     *         otherwise NULL is returned. Ownership of the heap descriptor is

     *         transferred to multiplexer (from observer).

     */

    virtual HBufC8* OutgoingMessageNotify( TUint aStreamId,

        TUint aConnectionId, const TInetAddr& aDestinationAddress,

        const TDesC8& aMessage ) = 0;      

    };

#endif // M_MNCMMESSAGEOBSERVER_H