/*

* Copyright (c) 2005-2009 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:

*

*/

#ifndef BTGPSNMEABUFFER_H

#define BTGPSNMEABUFFER_H

//  INCLUDES

#include <e32base.h>

// CONSTANTS

// Constants for NMEA buffer index, mean NMEA message

// has not been received by the client;

const TInt KBTGPSNmeaIndexNotSet = -1;

// MACROS

// DATA TYPES

// FUNCTION PROTOTYPES

// FORWARD DECLARATIONS

// CLASS DECLARATION

/**

*  This class is used to send messages to connected BT device. 

*  It doesn't garentee the message can be received from connected

*  BT device. The message are buffered if necessary to prevent

*  jams on BT connection.

*  

*/

class CBTGPSNmeaBuffer: public CBase

    {

    public: 

        /**

        * Two-phase construction.

        * @param aSize The size of NMEA buffer

        */

        static CBTGPSNmeaBuffer * NewL(TInt aSize);

        /**

        * Destructor

        */

        virtual ~CBTGPSNmeaBuffer();

        /**

        * Add NMEA sentences to buffer

        */

        void AddSentences(const TDesC8& aNmea);

        /**

        * Read NMEA sentences from buffer. 

        * After the sentence is rturned, aBeginning

        * is updated to the new position. When

        * the reading reaches the end, aBeginning

        * will be set as KBTGPSNmeaIndexNotSet.

        * @return KErrNone if nmea sentences are successfully

        * retrieved. Otherwise, the end of the buffer

        * is met.

        */

        TInt ReadSentences(

            TDes8& aDest, 

            TInt& aBeginning) const;

        /**

        * Return current index

        */

        TInt CurrentIndex() const;

        /**

        * Reset the buffer

        */

        void ResetBuffer();

    private:

        /**

        * Second phase of the construction

        */

        void ConstructL(TInt aSize);

        /**

        * Private constructor

        */

        CBTGPSNmeaBuffer();

    private:

        //NMEA buffer

        TUint8* iBuffer;

        //Size of the buffer

        TInt iSize;

        //End of the FIFO buffer

        TInt iBottom;

    };

#endif

// End of File