/*

* 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:  Plugin interface implementation, class description.

*

*/

#ifndef NSPINTERFACE_H

#define NSPINTERFACE_H

#include "nspplugin.h"

#include "nsputdefinitions.h"

class CNSPController;

/**

 *  NAT FW Sdp plugin interface implementation.

 *

 *  This class implements 'CNSPPlugin' ECOM interface.

 *

 *  @lib natfwsdpprovider.dll

 *  @since S60 3.2

 */

class CNSPInterface : public CNSPPlugin

    {

public: // Constructors and destructor

    /**

     * A two-phase constructor.

     */

    static CNSPInterface* NewL();

    /**

     * Destructor.

     */

    virtual ~CNSPInterface();

private: // Constructors and destructor

    CNSPInterface();

    void ConstructL();

public: // From CNSPPlugin

    /**

     * Creates session object, and returns a handle to that object.

     * Client of the class uses services via this handle.

     *

     * @since       S60 3.2

     * @param       aSessionObserver    Observer for created session, 

     *                                  for async callbacks.

     * @param       aIapId              Internet access point identifier, unique.

     * @param       aProtocol           Used transport protocol, values are:

     *                                  1 = TCP

     *                                  2 = UDP

     * @return      Session identifier, via this handle session is used.

     */

    TUint NewSessionL( MNSPSessionObserver& aSessionObserver,

            TUint32 aIapId, const TDesC8& aDomain, TUint aProtocol );

    /**

     * With this call NAT FW session is terminated.

     *

     * @since       S60 3.2

     * @param       aSessionId          Session unique identier.

     */

    void CloseSessionL( TUint aSessionId );

    /**

     * Sets the value of a session parameter.

     * 

     * @param       aSessionId          The ID identifying session.

     * @param       aParamKey           identifies the parameter.

     * @param       aParamValue         value of the parameter.

     * @return      KErrNotFound if the key is not found or

     *              other system wide error code on failure.

     */

    TInt SetSessionParam( TUint aSessionId, TNSPSessionParamKey aParamKey,

            TUint aParamValue );

    /**

     * Gets the value of a session parameter.

     * 

     * @param       aSessionId          The ID identifying session.

     * @param       aParamKey           identifies the parameter.

     * @return      value of the parameter or

     *              KErrNotFound if the value is not available or

     *              other system wide error code on failure.

     */

    TInt GetSessionParam( TUint aSessionId, TNSPSessionParamKey aParamKey );

    /**

     * Initial NAT FW specific SDP content added in here.

     *

     * @since       S60 3.2

     * @param       aSessionId          Session unique identier.

     * @param       aOffer              Sdp offer document

     */

    TNatReturnStatus CreateOfferL( TUint aSessionId, CSdpDocument*& aOffer );

    /**

     * NAT FW specific SDP content is added to both Offer and Answer.

     *

     * @since       S60 3.2

     * @param       aSessionId          Session unique identier.

     * @param       aOffer              Sdp offer document

     * @param       aAnswer             Sdp answer document

     */

    TNatReturnStatus ResolveL( TUint aSessionId,

            CSdpDocument*& aOffer, CSdpDocument*& aAnswer );

    /**

     * Answer to initial Answer interpred in here.

     *

     * @since       S60 3.2

     * @param       aSessionId          Session unique identier.

     * @param       aAnswer             Sdp answer document.

     */

    TNatReturnStatus DecodeAnswerL( TUint aSessionId, CSdpDocument*& aAnswer );

    /**

     * Offer can be updated while ResolveL is still ongoing, i.e.

     * OfferReady callback is not yet received.

     *

     * @since       S60 3.2

     * @param       aSessionId          Session unique identier.

     * @param       aOffer              Sdp offer document.

     */

    void UpdateL( TUint aSessionId, CSdpDocument*& aOffer );

    /**

     * Empty INVITE, with certain NAT protocols, can be interpret as request

     * to restart connection checks. This method must be called if such

     * a message is received.

     *

     * @since       S60 3.2

     * @param       aSessionId          Session unique identier.

     * @return      NAT status, if async signaling expected.

     */

    TNatReturnStatus RestartL( TUint aSessionId );

private: // data

    /**

     * Controller object, which is used to find sessions and check Sdp.

     * Own.

     */

    CNSPController* iController;

    /**

     * Definitions for unit testing.

     */

    NSP_UT_DEFINITIONS

    };

#endif // NSPINTERFACE_H

// end of file