/*

* Copyright (c) 2005 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:  Contains an implementation of CBTAudioStreamSenderSBC class.

*

*/

#include "btaudiostreamsendersbc.h"

#include "btaudiostreamerdebug.h" 

const TInt KA2DPMediaPacketHeaderLength = 1; 

const TInt KA2DPMediaPacketHeaderIndex = 0; 

const TInt KRTPHeaderLength = 12; 

// ======== MEMBER FUNCTIONS ========

// ---------------------------------------------------------------------------

// Constructor. 

// ---------------------------------------------------------------------------

//

CBTAudioStreamSenderSBC::CBTAudioStreamSenderSBC(MBTAudioStreamSenderObserver& aObserver, RRtpSession& aSession): 

        CBTAudioStreamSender(aObserver, aSession) 

    {

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::CBTAudioStreamSenderSBC() ->")));

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::CBTAudioStreamSenderSBC() <-")));

    }

// ---------------------------------------------------------------------------

// Factory method.

// ---------------------------------------------------------------------------

//

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

    {

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::NewL() ->")));

    CBTAudioStreamSenderSBC* self = new (ELeave) CBTAudioStreamSenderSBC(aObserver, aSession);

    CleanupStack::PushL(self);

    self->ConstructL();

    CleanupStack::Pop(self);

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::NewL() <-")));

    return self;

    }

// ---------------------------------------------------------------------------

// Destructor. 

// ---------------------------------------------------------------------------

//

CBTAudioStreamSenderSBC::~CBTAudioStreamSenderSBC() 

    {

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::~CBTAudioStreamSenderSBC() ->")));

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::~CBTAudioStreamSenderSBC() <-")));

    }

// ---------------------------------------------------------------------------

// From class CBTAudioStreamSender.

// This method stores the frames to the frame buffer and 

// when we have enough frames. 

// ---------------------------------------------------------------------------

//

TInt CBTAudioStreamSenderSBC::AddHeaderToSendPacket(TPtr8& aPayloadDesC) 

    {

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::AddHeaderToSendPacket() ->")));

    aPayloadDesC[KA2DPMediaPacketHeaderIndex] = iNumOfFramesInSendPacket; 

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::AddHeaderToSendPacket() <-")));

    return KErrNone; 

    }

// ---------------------------------------------------------------------------

// From class CBTAudioStreamSender.

// This method stores the frames to the frame buffer and 

// when we have enough frames. 

// ---------------------------------------------------------------------------

//

TInt CBTAudioStreamSenderSBC::AddBufferToSendPacket(const TDesC8& aBuffer) 

    {

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::AddBufferToSendPacket() ->")));

    // Copy data from the buffer to the outgoing packet. 

    // The return code means how many frames can still fit in the SendPacket. 

    //     - If there's more space, the value > 0. In this case we need more data. 

    //  - If the buffer is full and all data was consumed, the value == 0. In this case the packet must be sent. 

    //     - If the buffer is full and all data didn't fit in it, the value < 0. The packet must be sent and this method called again with the same frame. 

    // Calculate how many frames there's left in the buffer. Note that iFrameLength must always be greater than zero. 

    TInt numOfFramesLeftInBuffer = (aBuffer.Length() / iFrameLength) - iNumOfFramesAlreadyMoved ; 

    // If the whole buffer can fit in packet, move it completely, otherwise move as many frames as can fit. 

    TInt numOfFramesToMove = numOfFramesLeftInBuffer <= iMaxNumOfFrames - iNumOfFramesInSendPacket ? 

                            numOfFramesLeftInBuffer : 

                            iMaxNumOfFrames - iNumOfFramesInSendPacket; 

    // Some traces for seeing what's going on. 

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t Filling sendpacket...")));

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FPrint(_L("[BTAudioStreamer]\t %d frames can fit in packet."), iMaxNumOfFrames));    

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FPrint(_L("[BTAudioStreamer]\t %d frames have already been moved from current buffer to sendpacket."), iNumOfFramesAlreadyMoved));    

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FPrint(_L("[BTAudioStreamer]\t %d frames left to move from current buffer."), numOfFramesLeftInBuffer));    

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FPrint(_L("[BTAudioStreamer]\t %d frames already in current packet."), iNumOfFramesInSendPacket));    

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FPrint(_L("[BTAudioStreamer]\t => Moving %d frames."), numOfFramesToMove));    

    // Move the number of frames calculated above to the packet: 

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FPrint(_L("[BTAudioStreamer]\t replacing sendpacket content from %d, length is %d..."), KA2DPMediaPacketHeaderLength + iNumOfFramesInSendPacket * iFrameLength, numOfFramesToMove * iFrameLength));    

    // Make the ptrNextFrameInBuffer point to the first frame that hasn't been moved. 

    const TUint8 * ptrNextFrameInBuffer = aBuffer.Ptr() + iNumOfFramesAlreadyMoved * iFrameLength; 	

    memcpy((void *)iPtrEndOfPayload, (void *)ptrNextFrameInBuffer, numOfFramesToMove * iFrameLength); 

    iPtrEndOfPayload += numOfFramesToMove * iFrameLength; 

    ptrNextFrameInBuffer += numOfFramesToMove * iFrameLength; 

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FPrint(_L("[BTAudioStreamer]\t %d frames moved from buffer to packet."), numOfFramesToMove));    

    // If we have now moved them all, reset the counter, otherwise update it for the next round. 

    iNumOfFramesAlreadyMoved = numOfFramesLeftInBuffer == numOfFramesToMove ? 0 : iNumOfFramesAlreadyMoved + numOfFramesToMove; 

    // update the information needed for building the header later (in sending phase): 

    iNumOfFramesInSendPacket += numOfFramesToMove; 

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FPrint(_L("[BTAudioStreamer]\t iNumOfFramesInSendPacket incremented, it is now %d"), iNumOfFramesInSendPacket));    

    numOfFramesLeftInBuffer -= numOfFramesToMove; 

    // return the number of frames that will still fit in the packet: 

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FPrint(_L("[BTAudioStreamer]\t returning: %d"), iMaxNumOfFrames - iNumOfFramesInSendPacket - numOfFramesLeftInBuffer));    

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::AddBufferToSendPacket() <-")));

    return (iMaxNumOfFrames - iNumOfFramesInSendPacket - numOfFramesLeftInBuffer); 

    }

// ---------------------------------------------------------------------------

// From class CBTAudioStreamSender.

// This method stores the frames to the frame buffer and 

// when we have enough frames. 

// ---------------------------------------------------------------------------

//

TInt CBTAudioStreamSenderSBC::PacketSendingCompleted(TPtr8& aPayloadDesC) 

    {

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::PacketSendingCompleted() ->")));

    iNumOfFramesInSendPacket = 0; 

    iPtrEndOfPayload = aPayloadDesC.Ptr() + KA2DPMediaPacketHeaderLength; 

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::PacketSendingCompleted() <-")));

    return KErrNone; 

    }

// ---------------------------------------------------------------------------

// From class CBTAudioStreamSender.

// This method sets up the sender and calculates the required packet  

// length according to its own implementation. 

// ---------------------------------------------------------------------------

//

TInt CBTAudioStreamSenderSBC::InitSender(RRtpSendPacket& aSendPacket, TPtr8& aPayloadDesC, const TUint aTargetBitrate) 

    {

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::InitSender() ->")));

    iFrameLength = iNewFrameLength; 

    iMaxNumOfFrames = iSpaceNeededForBuffer / iFrameLength; 

    // Make the descriptor point in the beginning of the send packet. 

    aPayloadDesC.Set(const_cast<TUint8*>(aSendPacket.WritePayload().Ptr()), iSpaceNeededForBuffer, iSpaceNeededForBuffer);

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FPrint(_L("[BTAudioStreamer]\t Descriptor inited, space needed: %d bytes."), iSpaceNeededForBuffer));    

    iPtrEndOfPayload = aPayloadDesC.Ptr() + KA2DPMediaPacketHeaderLength; 

    iNumOfFramesInSendPacket = 0; 

		iTimestampOfFirstFrameInSendPacket = 0; 

		iDurationOfFrame = CalculateFrameDuration(iFrameLength, aTargetBitrate); 

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FPrint(_L("[BTAudioStreamer]\t iDurationOfFrame: %d"), iDurationOfFrame));    

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::InitSender() <-")));

    return KErrNone; 

    }

TInt CBTAudioStreamSenderSBC::CalculatePacketLength(TUint aOutboundMTUSize, const TUint aFrameLength) 

    {

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::CalculatePacketLength() <-")));

		if(aFrameLength > 0) // Must not be zero, and cannot be according to A2DP spec. 

		    {

        iNewFrameLength = aFrameLength; 

				iSpaceNeededForBuffer = ((aOutboundMTUSize - KA2DPMediaPacketHeaderLength - KRTPHeaderLength) / iNewFrameLength) * iNewFrameLength + KA2DPMediaPacketHeaderLength; 

    		BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::CalculatePacketLength() <-")));

        return iSpaceNeededForBuffer; 

        }

    else 

        {

        BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FPrint(_L("[BTAudioStreamer]\t Length parameter is zero!")));    

		    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::CalculatePacketLength() <-")));

        return 0; 

        }

    }

TUint CBTAudioStreamSenderSBC::CalculateFrameDuration(const TUint aFrameLength, const TUint aTargetBitrate) 

    {

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::CalculateFrameInterval() ->")));

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::CalculateFrameInterval() <-")));

    return static_cast<TUint>(static_cast<TReal>(aFrameLength * 8) / static_cast<TReal>(aTargetBitrate)  * 1000000.0); 

    }

TUint CBTAudioStreamSenderSBC::MaxFramesPerPacket()  

    {

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::FramesPerPacket() ->")));

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::FramesPerPacket() <-")));

    return iMaxNumOfFrames; 

    }

void CBTAudioStreamSenderSBC::AdjustTimestamp(TInt64& aTimestamp) 

    {

    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::AdjustTimestamp() ->")));

		// The buffer has been emptied, but there may be space for additional frames in sendpacket. 

		// So keep the current timestamp until the sendpacket becomes full. 

	  if(iNumOfFramesAlreadyMoved == 0) 

			  {

		    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t Buffer became empty.")));

				iTimestampChangeFlag = ETrue; 

			  }

		if(iNumOfFramesInSendPacket == iMaxNumOfFrames) // Adjust the timestamp only when the sendpacket is full. 

				{

				if(iTimestampChangeFlag != EFalse) 

						{

						// When the buffer been emptied earlier, take the new timestamp into use and adjust it by the amount of frames we just moved. 

						iTimestampOfFirstFrameInSendPacket = aTimestamp + iDurationOfFrame * iNumOfFramesAlreadyMoved; 

				    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FPrint(_L("[BTAudioStreamer]\t New timestamp %d (low) is in use."), I64LOW(aTimestamp))); 

				    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FPrint(_L("[BTAudioStreamer]\t New timestamp %d (high) is in use."), I64HIGH(aTimestamp))); 

						iTimestampChangeFlag = EFalse; 

						}

		    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FPrint(_L("[BTAudioStreamer]\t Timestamp is %d (low)"), I64LOW(iTimestampOfFirstFrameInSendPacket)));    

		    BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FPrint(_L("[BTAudioStreamer]\t Timestamp is %d (high)"), I64HIGH(iTimestampOfFirstFrameInSendPacket)));    

				// Use the timestamp first and then do a normal adjustment for the next round. 

				aTimestamp = iTimestampOfFirstFrameInSendPacket; 

		    iTimestampOfFirstFrameInSendPacket = iTimestampOfFirstFrameInSendPacket + iMaxNumOfFrames * iDurationOfFrame; 

				}

	  BT_AUDIO_STREAMER_TRACE_OPT( KPRINTFTRACE, FLOG(_L("[BTAudioStreamer]\t CBTAudioStreamSenderSBC::AdjustTimestamp() <-")));

    }