/*

* 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:    Session observer class, implemented by plugin client.

*

*/

#ifndef NSPSESSIONOBSERVER_H

#define NSPSESSIONOBSERVER_H

#include <e32def.h>

class CSdpDocument;

/**

 * Error limit which can be used to signal situations where Nat failed in

 * asynchronous prosessing, and resume of normal SIP signaling is expected.

 * All errors below this limit are considered as non-fatal, and normal SIP

 * session is maintained without informing MCE Client.

 */

const TInt KNatNonFatalErrorLimit = -11000;

/**

 *  Session observer, implemented by plugin client to receive async calls.

 *

 *  @lib natfwsdpprovider.dll

 *  @since S60 3.2

 */

class MNSPSessionObserver

    {

public: // New functions

    /**

     * Callback for signaling that session is initialized, and ready for use.

     */

    virtual void Initialized( TUint aSessionId ) = 0;

    /**

     * Callback for signaling that Offer is modified to point NAT.

     *

     * @param   aSessionId       Session unique identier.

     * @param   aOffer           Modified Offer, ownership transferred.

     */

    virtual void OfferReady( TUint aSessionId, CSdpDocument* aOffer ) = 0;

    /**

     * Callback for signaling that Answer is modified to point NAT.

     *

     * @param   aSessionId       Session unique identier.

     * @param   aAnswer          Modified Answer, ownership transferred.

     */

    virtual void AnswerReady( TUint aSessionId, CSdpDocument* aAnswer ) = 0;

    /**

     * Callback for signaling that NAT negotiation has resulted

     * a different result than original SDP A/O. Hence updated SDP content

     * must be sent. Only Controlling agent receives this callback.

     *

     * @param   aSessionId       Session unique identier.

     * @param   aOffer           Last SDP document, but with modified content.

     *                           Ownership transferred.

     */

    virtual void UpdateSdp( TUint aSessionId, CSdpDocument* aOffer ) = 0;

    /**

     * Session errors. Session which is identified by aSessionId is deleted.

     *

     * @param   aSessionId       Session unique identier.

     * @param   aError           System wide error code.

     */

    virtual void ErrorOccurred( TUint aSessionId, TInt aError ) = 0;

    /**

     * Session media related ICMP error occured.

     *

     * @param   aSessionId       Session unique identier.

     * @param   aError           ICMP error code.

     */

    virtual void IcmpErrorOccurred( TUint aSessionId, TInt aError ) = 0;

    };

#endif // NSPSESSIONOBSERVER_H

// end of file