/*

* Copyright (c) 2006 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:  This class implements the SBC codec specific data handling. 

*

*/

#ifndef __BTAUDIOSTREAMSENDERSBC_H__

#define __BTAUDIOSTREAMSENDERSBC_H__

#include "btaudiostreamsender.h" 

/**

 *  SBC codec specific implementation of CBTAudioStreamSender base class 

 *

 *  This class wraps the handling of SBC frames and it can place the 

 *  media packet header in place. 

 *  @lib btaudiostreamer.lib

 *  @since S60 v3.1 

 */

NONSHARABLE_CLASS(CBTAudioStreamSenderSBC) : public CBTAudioStreamSender

    {

    public:

    static CBTAudioStreamSenderSBC* NewL(MBTAudioStreamSenderObserver& aObserver, RRtpSession& aSession);

    virtual ~CBTAudioStreamSenderSBC();

    private:

    CBTAudioStreamSenderSBC(MBTAudioStreamSenderObserver& aObserver, RRtpSession& aSession);

    /**

     * From CBTAudioStreamSender.

     * This method places to received buffer into the send packet in SBC specific way. 

     *

     * @since S60 v3.1

     * @param aBuffer contains the SBC frames. 

     */

    virtual TInt AddBufferToSendPacket(const TDesC8& aBuffer); 

    /**

     * From CBTAudioStreamSender.

     * This method places the SBC codec specific media packet header in its place. 

     *

     * @since S60 v3.1

     * @param void. 

     * @return a Symbian OS wide error code. 

     */

    virtual TInt AddHeaderToSendPacket(TPtr8& aPayloadDesC); 

    /**

     * From CBTAudioStreamSender.

     * This method does the cleanup work after the packet has been sent. 

     *

     * @since S60 v3.1

     * @param void. 

     * @return a Symbian OS wide error code. 

     */

    virtual TInt PacketSendingCompleted(TPtr8& aPayloadDesC); 

    /**

     * From CBTAudioStreamSender.

     * This method is used for calculating the required packet length. 

     * It takes the header's into account and tries to fit as many frames 

     * to the packet that can fit to the outgoing MTU. 

     *

     * @since S60 v3.1

     * @param aOutboundMTUSize The MTU size for outgoing L2CAP link. 

     * @param aFrameLength  The length of one SBC frame. 

     */

    virtual TInt CalculatePacketLength(TUint aOutboundMTUSize, TUint aFrameLength); 

    /**

     * From CBTAudioStreamSender.

     * This method prepares the class for sending packets. 

     *

     * @since S60 v3.1

     * @param void. 

     * @return a Symbian OS wide error code. 

     */

    virtual TInt InitSender(RRtpSendPacket& aSendPacket, TPtr8& aPayloadDesC, const TUint aTargetBitrate); 

    /**

     * From CBTAudioStreamSender.

     * This method corrects the timestamp value when incoming buffers can't fit in one sendpacket. 

     *

     * @since S60 v5.0

     * @param void. 

     * @return void.

     */

		virtual void AdjustTimestamp(TInt64 &aTimestamp); 

    /**

     * 

     * This method calculates the playing time of one frame in microseconds. 

     * Information is used also internally for correcting the timestamp values. 

     *

     * @since S60 v5.0

     * @param void. 

     * @return a duration of one frame. 

     */

    virtual TUint CalculateFrameDuration(const TUint aFrameLength, const TUint aTargetBitrate); 

	/**

     * This method returns the maximum number of frames in one outgoing packet.  

     *

     * @since S60 Timebox 9.2

     * @return number of frames in one send packet. 

     */

	virtual TUint MaxFramesPerPacket(); 

    private: 

    /**

     * Stores the corrected timestamp value. 

     */

		TInt64 iTimestampOfFirstFrameInSendPacket; 

    /**

     * Stores the length of one SBC frame. 

     */

    TInt iFrameLength; 

    /**

     * Stores the length of one SBC frame. Used when the frame length changes. 

     */

    TInt iNewFrameLength; 

    /**

     * Stores the duration of one SBC frame in microseconds. Used for correcting the timestamps in long buffers. 

     */

    TInt iDurationOfFrame; 

    /**

     * Used for calculating how many frames can fit in one SendPacket. 

     */

		TInt iSpaceNeededForBuffer; 

    /**

     * Stores the number of frames we have moved from buffer to packet so far. 

     * This variable is needed when the whole buffer can't fit in the current packet. 

     */

    TInt iNumOfFramesAlreadyMoved; 

    /**

     * Stores the maximum number of frames that we can place in one packet. 

     */

    TInt iMaxNumOfFrames; 

    /**

     * This stores the number of frames in send packet. 

     * This information is needed for A2DP media packet header. 

     */

    TInt iNumOfFramesInSendPacket; 

    /**

     * This stores the end position of the SendPacket's payload. 

     */

    const TUint8 *iPtrEndOfPayload; 

    /**

     * This stores the number of frames that haven't been sent yet. It's needed if 

     * there's more incoming frames than can fit in single SendPacket. 

     */

    TInt iNumOfFramesLeftInBuffer; 

    /**

     * This tells if it is time to start using the passed in timestamp as reference. 

     */

		TBool iTimestampChangeFlag; 

    };

#endif // __BTAUDIOSTREAMSENDERSBC_H__