/*

* Copyright (c) 2003-2009 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:

* Name          : SdpKeyField.h

* Part of       : SDP Codec

* Interface     : SDK API, SDP Codec API

* Version       : 1.0

*

*/

#ifndef CSDPKEYFIELD_H

#define CSDPKEYFIELD_H

//  INCLUDES

#include <e32base.h>

#include <stringpool.h>

// FORWARD DECLARATIONS

class RReadStream;

class RWriteStream;

// CLASS DECLARATION

/**

 *  @publishedAll

 *  @released

 *

 *	This class encapsulates the encryption key field of 

 *  the Session Description Protocol.

 * 

 *	The normative reference for correct formatting and values is

 *	draft-ietf-mmusic-sdp-new-14 unless specified otherwise in

 *  member documentation. The implementation supports this normative

 *  reference, but does not enforce it fully. 

 *

 *  @lib sdpcodec.lib

 */

class CSdpKeyField : public CBase

	{

    public: // Constructors and destructor

        /**

         *	Constructs a new encryption key field.

		 *	

         *	@param aFieldValue A string containing a correctly 

         *         formatted field value terminated by a CRLF.

         *	@return a new instance.

         */

		IMPORT_C static CSdpKeyField* DecodeL(const TDesC8& aFieldValue);

        /**

         *	Constructs a new encryption key field and adds the pointer to 

         *  the cleanup stack.

		 *	

         *	@param aFieldValue A string containing a correctly 

         *              formatted field value terminated by a CRLF.

         *	@return a new instance.

         *  @leave  In error case function leaves.

         */

		IMPORT_C static CSdpKeyField* DecodeLC(const TDesC8& aFieldValue);

        /**

         *	Constructs a new encryption key field.

		 *	

         *	@param aMethod Encryption method from the pre-defined 

         *         SDP string table. User defined values are not accepted.

		 *  @param aEncryptionKey A valid encryption key value 

         *         or an empty descriptor to omit the key part.

         *	@return a new instance.

         */

		IMPORT_C static CSdpKeyField* NewL(RStringF aMethod,

											const TDesC8& aEncryptionKey);

        /**

         *	Constructs a new encryption key field and adds the pointer to 

         *  the cleanup stack.

		 *	

         *	@param aMethod Encryption method from the pre-defined 

         *         SDP string table. User defined values are not accepted.

		 *  @param aEncryptionKey A valid encryption key value 

         *         or an empty descriptor to omit the key part.

         *	@return a new instance.

         */

		IMPORT_C static CSdpKeyField* NewLC(RStringF aMethod,

											const TDesC8& aEncryptionKey);

		/**

		 *	Deletes the resources held by the instance.

		 */

		IMPORT_C ~CSdpKeyField();

    public: // New functions

		/**

		 *	Writes the instance as a complete SDP field encoded as UTF-8

		 *	and formatted as defined in draft-ietf-mmusic-sdp-new-14.

         *

		 *	@param aStream Stream used for output. On return 

         *         the stream includes correctly formatted key field.

		 */

		IMPORT_C void EncodeL(RWriteStream& aStream) const;

		/**

		 *	Creates a new instance that is equal to the target.

		 *

		 *	@return a new instance.

		 */

		IMPORT_C CSdpKeyField * CloneL() const;

		/**	

		 *	Compares this instance to another for equality.

		 *

		 *	@param aObj The instance to compare to.

		 *	@return ETrue if equal, EFalse if not.

		 */

		IMPORT_C TBool operator == (const CSdpKeyField& aObj) const;

		/**

		 *	Gets the encryption method.

		 *

		 *	@return The method.

		 */

		IMPORT_C RStringF Method() const;

		/**

		 *	Gets the encryption key.

		 *

		 *	@return The key or an empty descriptor if there is no key part.

		 */

		IMPORT_C const TDesC8& EncryptionKey() const;

		/**

		 *	Sets the encryption method and key.

		 *

         *	@param aMethod Encryption method from the pre-defined 

         *         SDP string table. User defined values are not accepted.

		 *  @param aEncryptionKey A valid encryption key value 

         *         or an empty descriptor to omit the key part.

		 */

		IMPORT_C void SetL(RStringF aMethod,

						   const TDesC8& aEncryptionKey);

    public:

    	/**

         *  Externalizes the object to stream

         *

         *  @param aStream Stream where the object's state will be stored

         */

		void ExternalizeL(RWriteStream& aStream) const;

		/**

         *  Creates object from the stream data

         *

         *  @param aStream Stream where the object's state will be read        

         *  @return Initialized object

         */

		static CSdpKeyField* InternalizeL(RReadStream& aStream);

	private:

		CSdpKeyField();

		void ConstructL(const TDesC8& aText);

		void ConstructL(RStringF aMethod, const TDesC8& aEncryptionKey);

        void DoInternalizeL(RReadStream& aStream);

        void SetMethodAndKeyL(RStringF aMethod, 

                              const TDesC8& aEncryptionKey,

                              TBool aAllowEmptyKeyValue);

        void SetMethodClearAndKeyL(RStringF aMethod, const TDesC8& aEncryptionKey);

        void SetMethodBase64AndKeyL(RStringF aMethod, const TDesC8& aText);

        void SetMethodUriAndKeyL(RStringF aMethod, const TDesC8& aText);

        void SetMethodPromptL(RStringF aMethod, const TDesC8& aText);

        RArray<TPtrC8> GetElementsFromLineL( TLex8& aLexer);

    private: // Data

		RStringF iMethod;

        TBool iMethodOpen;

		HBufC8* iEncryptionKey;

        RStringPool iStringPool;

		void __DbgTestInvariant() const;

	};

#endif // CSDPKEYFIELD_H