/*

* 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 CNATFWUNSAFATTRIBUTE_H

#define CNATFWUNSAFATTRIBUTE_H

// INCLUDES

#include <e32base.h>

#include "natfwinternaldefs.h"    //UNIT_TEST

// FORWARD DECLARATIONS

// CLASS DECLARATION

/**

 * An abstract base class for UNSAF attributes.

 */

class CNATFWUNSAFAttribute : public CBase

    {

    public: // Enumerations

        enum TType // Values are from RFC 3489 and TURN-draft

            {

            EMappedAddress = 0x0001,

            EResponseAddress = 0x0002,

            EChangeRequest = 0x0003,

            ESourceAddress = 0x0004,

            EChangedAddress = 0x0005,

            EUsername = 0x0006,

            EPassword = 0x0007,

            EMessageIntegrity = 0x0008,

            EErrorCode = 0x0009,

            EUnknownAttributes = 0x000a,

            EReflectedFrom = 0x000b,

            ELifetime = 0x000d,

            EMagicCookie = 0x000f,

            EBandwidth = 0x0010,

            EDestinationAddress = 0x0011,

            ERemoteAddress = 0x0012,

            EData = 0x0013,

            ERealm = 0x0014,

            ENonce = 0x0015,

            ERelayAddress = 0x0016,

            ERequestedPortProps = 0x0018,

            ERequestedTransport = 0x0019,

            EXorMappedAddress = 0x0020,

            ETimerVal = 0x0021,

            ERequestedIp = 0x0022,

            EConnectStat = 0x0023,

            EPriority = 0x0024,

            EUseCandidate = 0x0025,

            EXorOnly = 0x8021,      //was 0x0021, but clashes with TIMER_VAL

            EServer = 0x8022,

            EAlternateServer = 0x8023,

            EFingerprint = 0x8028,

            EIceControlled = 0x8029,

            EIceControlling = 0x802a

            };

    public: // Constructors and destructor

        /**

        * Destructor, deletes the resources of CNATFWUNSAFAttribute.

        */

        virtual ~CNATFWUNSAFAttribute();

    public: // New pure virtual functions

        /**

        * The type of the UNSAF attribute

        * @return UNSAF attribute type

        */

        virtual CNATFWUNSAFAttribute::TType Type() const = 0;

    public: // New functions

        /**

        * Encodes the UNSAF attribute including its type and length

        * @return The encoded UNSAF attribute. The ownership is

        *         transferred.

        */

        HBufC8* EncodeL() const;

        /**

        * Parses the byte stream for a UNSAF attribute type and length.

        * Leaves if stream does not contain enough data

        * @param aByteStream Stream to parse

        * @param aType OUT: attribute type

        * @param aTotalLength OUT: Total length of the attribute, including

        *    type, length and value elements

        * @leave KErrArgument If the stream doesn't contain enough data

        */

        static void ParseTypeAndLengthL(const TDesC8& aByteStream,

                                        TUint16& aType,

                                        TUint16& aLength);

        /**

        * Checks if the UNSAF attribute indicated by aType is mandatory to

        * understand.

        * @param aType UNSAF attribute type

        * @return ETrue  Attribute is mandatory and must be understood

        *         EFalse Attribute is optional

        */

        static TBool IsMandatory(TUint16 aType);

        /**

        * Checks if the UNSAF attribute indicated by aType is word boundary

        * aligned by definition.

        * @param aType UNSAF attribute type

        * @return ETrue  Attribute is word boundary aligned and must not be

        *                padded out.

        *         EFalse Attribute may need padding out.

        */

        static TBool IsWordBoundaryAligned(TUint16 aType);

    protected: // Enums

        enum TEncodedAttributeOffset

            {

            //Offset to fields inside the encoded attribute

            ETypeOffset = 0,

            ELengthOffset = 2,

            EValueOffset = 4

            };

    protected: // Constructors

        CNATFWUNSAFAttribute();

    protected: // New pure virtual functions

        /**

        * Encodes the UNSAF attribute value.

        * Used from CNATFWUNSAFAttribute::EncodeL.

        * @return The encoded UNSAF attribute value.

        *         The ownership is transferred.

        */

        virtual HBufC8* EncodeValueL() const = 0;

    protected: // New functions

        /**

        * Parses the byte stream and returns the value of length element.

        * @param aByteStream Stream to parse

        * @return Length of value element

        * @leave KErrArgument If the stream doesn't contain enough data

        */

        static TUint16 ParseLengthL(const TDesC8& aByteStream);

    private: // For testing purposes

        UNIT_TEST(CNATFWUNSAFMessageTest)

        UNIT_TEST(CNATFWUNSAFMessageFactoryTest)

        UNIT_TEST(CNATFWUNSAFMappedAddressAttributeTest)

        UNIT_TEST(CNATFWUNSAFMessageIntegrityAttributeTest)

    };

#endif // CNATFWUNSAFATTRIBUTE_H