/*

* Copyright (c) 2006-2007 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:   

*

*/

#ifndef CNATFWUNSAFMESSAGEFACTORY_H

#define CNATFWUNSAFMESSAGEFACTORY_H

//  INCLUDES

#include <e32base.h>

#include "natfwunsafmessage.h"

#include "natfwunsaftransactionid.h"

// FORWARD DECLARATIONS

class CAttributeLookupTable;

class CMessageLookupTable;

// CLASS DECLARATION

/**

* Class acts as a factory for NATFWUNSAF requests and responses

* hiding the actual message types from the user

*

*  @lib natfwunsafprotocols.lib

*/

class CNATFWUNSAFMessageFactory : public CBase

    {

    public: // Constructors and destructors

        /**

        * Creates a CNATFWUNSAFMessageFactory instance

        * @return A new instance of CNATFWUNSAFMessageFactory

        */

        IMPORT_C static CNATFWUNSAFMessageFactory* NewL();

        /**

        * Creates a CNATFWUNSAFMessageFactory instance and pushes it to

        * CleanupStack

        * @return A new instance of CNATFWUNSAFMessageFactory

        */

        IMPORT_C static CNATFWUNSAFMessageFactory* NewLC();

        /**

        * Destructor

        */

        IMPORT_C virtual ~CNATFWUNSAFMessageFactory();

    public: // New functions

        /**

        * Parses the UNSAF message length from a UNSAF message

        * (bytes 3 and 4) and returns the parsed length.

        * @param aNATFWUNSAFMessage a UNSAF message

        * @return KErrNotFound if length field cannot be parsed.

        *         Otherwise the value of the length field.

        */

        TInt MessageLength(const TDesC8& aNATFWUNSAFMessage) const;

        /**

        * Parses a UNSAF message including the 20 byte UNSAF

        * message header

        * @param aNATFWUNSAFMessage a UNSAF message

        * @return A new instance of CNATFWUNSAFMessage.

        *         The ownership is transferred.

        */

        IMPORT_C CNATFWUNSAFMessage* DecodeL(

            const TDesC8& aNATFWUNSAFMessage) const;

        /**

        * Creates a UNSAF message instance without any UNSAF

        * attributes

        * @param aType a UNSAF message type

        * @param aTransactionID a NATFWUNSAF transaction ID

        * @return A new instance of CNATFWUNSAFMessage.

        *         The ownership is transferred.

        */

        CNATFWUNSAFMessage* CreateL(const CNATFWUNSAFMessage::TType& aType,

            const TNATFWUNSAFTransactionID& aTransactionID) const;

    private:

        CNATFWUNSAFMessageFactory();

        void ConstructL();

        /**

        * Decodes a UNSAF message header, instantiates a UNSAF message of an

        * appropriate type and pushes it into CleanupStack.

        * @param aNATFWUNSAFMessage Byte stream to decode as a UNSAF message

        * @return A new instance of CNATFWUNSAFMessage.

        * The ownership is transferred.

        */

        CNATFWUNSAFMessage* DecodeHeaderLC(

            const TDesC8& aNATFWUNSAFMessage) const;

    private: // Data

        //NATFWUNSAF codec is only used by the NAT traversal-server,´

        //so TLS need not be used

        //Owned

        CAttributeLookupTable* iAttributeLookupTable;

        //Owned

        CMessageLookupTable* iMessageLookupTable;

    private: // For testing purposes

        __DECLARE_TEST;

    };

#endif // CNATFWUNSAFMESSAGEFACTORY_H