// Copyright (c) 2002-2009 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:

//

#include "MmfUtilities.h"

#include "mmfutilitiespriv.h"

#include "mmf/utils/rateconvert.h"

const TInt KMaxInt16Bit = 65536 ; //Maximum for a 16bit int

EXPORT_C CMMFChannelAndSampleRateConverterFactory::~CMMFChannelAndSampleRateConverterFactory()

	{

	delete iConverter;

	}

EXPORT_C CMMFChannelAndSampleRateConverter* CMMFChannelAndSampleRateConverterFactory::CreateConverterL(TInt aFromRate,TInt aFromChannels,

													   TInt aToRate,TInt aToChannels)

	{

	if(aFromRate<0 || aFromChannels<0 || aToRate<0 || aToChannels<0)

		{

		User::Leave(KErrArgument);

		}

	iFromRate=aFromRate;

	iToRate=aToRate;

	iFromChannels=aFromChannels;

	iToChannels=aToChannels;

	return CreateConverterL();

	}

EXPORT_C CMMFChannelAndSampleRateConverter* CMMFChannelAndSampleRateConverterFactory::CreateConverterL()

	{

	if (iConverter

		&&(iFromRate==iConverter->iFromRate)

		&&(iToRate==iConverter->iToRate)

		&&(iFromChannels==iConverter->iFromChannels)

		&&(iToChannels==iConverter->iToChannels))

		return iConverter;

	delete iConverter;

	iConverter=NULL;

	iConverter = CMMFForwardingChannelAndSampleRateConverter::NewL(iFromRate, iFromChannels, iToRate, iToChannels);

	return iConverter;

	}

// SetRates kept for BC reasons - populates publically visible properties

void CMMFChannelAndSampleRateConverter::SetRates(TInt aFromRate,TInt aFromChannels,

											 TInt aToRate,TInt aToChannels)

	{

	iFromRate=aFromRate;

	iToRate=aToRate;

	iFromChannels=aFromChannels;

	iToChannels=aToChannels;

	iRatio = (TReal)aFromRate / (TReal)aToRate;

	TInt quotient = (TInt)iRatio;

	TReal remainder = iRatio - (TReal)quotient;

	iFraction = quotient * KMaxInt16Bit + (TInt32)(remainder * KMaxInt16Bit);

	Reset();

	}

//

// Forwarding converter - adapt to the implementation in audioutils.

//

CMMFForwardingChannelAndSampleRateConverter* CMMFForwardingChannelAndSampleRateConverter::NewL(TInt aFromRate,

																							   TInt aFromChannels,

										    			      								   TInt aToRate,

										    			      								   TInt aToChannels)

	{

	CMMFForwardingChannelAndSampleRateConverter* self = new (ELeave) CMMFForwardingChannelAndSampleRateConverter;

	CleanupStack::PushL(self);

	self->ConstructL(aFromRate,aFromChannels,aToRate,aToChannels);

	CleanupStack::Pop(self);

	return self;

	}

CMMFForwardingChannelAndSampleRateConverter::CMMFForwardingChannelAndSampleRateConverter()

	{

	}

void CMMFForwardingChannelAndSampleRateConverter::ConstructL(TInt aFromRate,

															 TInt aFromChannels,

										    			     TInt aToRate,

										    			     TInt aToChannels)

	{

	SetRates(aFromRate, aFromChannels, aToRate, aToChannels); 

		// delib called before iRealConverter created. Reset() will be no-op.

		// this is preserved solely to keep BC with original API that exposes too much

	iRealConverter = CChannelAndSampleRateConverter::CreateL(aFromRate,aFromChannels,aToRate,aToChannels);

	}

CMMFForwardingChannelAndSampleRateConverter::~CMMFForwardingChannelAndSampleRateConverter()

	{

	delete iRealConverter;

	}

TInt CMMFForwardingChannelAndSampleRateConverter::Convert(const CMMFDataBuffer& aSrcBuffer, CMMFDataBuffer& aDstBuffer)

	{

	TInt ignore = iRealConverter->Convert(aSrcBuffer.Data(), aDstBuffer.Data());

	// CChannelAndSampleRateConverter returns the source length converted

	// while the old API wants the destination generated, so change. 

	TInt result = aDstBuffer.Data().Length(); 

	return result;

	}

void CMMFForwardingChannelAndSampleRateConverter::Reset()

	{

	// need to check iRealConverter created. Won't be true during construction

	if (iRealConverter)

		{

		iRealConverter->Reset();

		}

	}

TUint CMMFForwardingChannelAndSampleRateConverter::MaxConvertBufferSize(TUint aSrcBufferSize)

	{

	return TUint(iRealConverter->MaxConvertBufferSize(aSrcBufferSize));

	}

//

// Old derivatives of CMMFChannelAndSampleRateConverter. These were previously returned by

// CreateConverterL(). Kept for BC, but no longer used by main code.

//

TInt CMMFStereoToStereoRateConverter::Convert(const CMMFDataBuffer& aSrcBuffer, CMMFDataBuffer& aDstBuffer)

	{

	TInt32* aSrc = (TInt32*)aSrcBuffer.Data().Ptr();

	TInt32* aDst = (TInt32*)aDstBuffer.Data().Ptr();

	TUint aSamples = aSrcBuffer.Data().Length()/4;

	TInt32* src = aSrc;

	TInt32* dst = aDst;

	TInt32* limit=src+aSamples;

	// add left over from last buffer

	TUint index = iIndex;

	src = aSrc + (index>>16);

	while(src<limit)

		{

		*dst++ = *src;

		index += iFraction;

		src = aSrc + (index>>16);

		}

	// get amount by which index exceeded end of buffer

	// so that we can add it back to start of next buffer

	iIndex = index - (aSamples << 16);

	// return sample byte count and setup output buffer

	TInt length = (dst-(TInt32*)aDst)*4;	//dealing with 32bit values so multiply by 4 for bytes

	aDstBuffer.Data().SetLength(length); //adjust length of destination buffer

	return (length);

	}	

TInt CMMFMonoToStereoRateConverter::Convert(const CMMFDataBuffer& aSrcBuffer, CMMFDataBuffer& aDstBuffer)

	{

	TInt16* aSrc = (TInt16*)aSrcBuffer.Data().Ptr();

	TInt16* aDst = (TInt16*)aDstBuffer.Data().Ptr();

	TUint aSamples = aSrcBuffer.Data().Length()/2;

	TInt16* src = aSrc;

	TInt16* dst = aDst;

	TInt16* limit=aSrc+aSamples;

	// add left over from last buffer

	TUint index = iIndex;

	src = aSrc + (index>>16);

	while(src<limit)

		{

		*dst++ = *src;

		*dst++ = *src;

		index += iFraction;

		src = aSrc + (index>>16);

		}

	// get amount by which index exceeded end of buffer

	// so that we can add it back to start of next buffer

	iIndex = index - (aSamples << 16);

	// return sample byte count and setup output buffer

	TInt length = (dst-aDst) * 2;		// size in bytes

	aDstBuffer.Data().SetLength(length); //adjust length of destination buffer

	return (length);

	}	

TUint CMMFMonoToStereoRateConverter::MaxConvertBufferSize(TUint aSrcBufferSize)

	{

	return aSrcBufferSize*2;

	}

TInt CMMFMonoToMonoRateConverter::Convert(const CMMFDataBuffer& aSrcBuffer, CMMFDataBuffer& aDstBuffer)

	{

	TInt16* aSrc = (TInt16*)aSrcBuffer.Data().Ptr();

	TInt16* aDst = (TInt16*)aDstBuffer.Data().Ptr();

	TUint aSamples = aSrcBuffer.Data().Length()/2;

	TInt16* src = aSrc;

	TInt16* dst = aDst;

	TInt16* limit=aSrc+aSamples; //*2 ???

	// add left over from last buffer

	TUint index = iIndex;

	src = aSrc + (index>>16);

	while(src<limit)

		{

  		*dst++ = *src;

		index += iFraction;

		src = aSrc + (index>>16);

		}

	// get amount by which index exceeded end of buffer

	// so that we can add it back to start of next buffer

	iIndex = index - (aSamples << 16);

	// return sample byte count and setup output buffer

	TInt length = (dst-aDst)*2;			// size in bytes

	aDstBuffer.Data().SetLength(length); //adjust length of destination buffer

	return (length);

	}	

//This method takes the left and right sample of interleaved PCM and sums it, then divides by 2

TInt CMMFStereoToMonoRateConverter::Convert(const CMMFDataBuffer& aSrcBuffer, CMMFDataBuffer& aDstBuffer)

	{

	TInt16* aSrc = (TInt16*)aSrcBuffer.Data().Ptr();

	TInt16* aDst = (TInt16*)aDstBuffer.Data().Ptr();

	TUint aSamples = aSrcBuffer.Data().Length()/4;

	TInt16* src = aSrc;

	TInt16* limit=aSrc+aSamples*2;	//because 1 sample = two TInt16s

	// add left over from last buffer

	TUint index = iIndex;

	src = aSrc + (index>>16)*2;

	TInt length = 0;

	while(src<limit)

		{

		*aDst++ = (TInt16)((src[0] + (src[1])) / 2);

		index += iFraction;

		src = aSrc + (index>>16)*2;

		length++;

		}

	// get amount by which index exceeded end of buffer

	// so that we can add it back to start of next buffer

	iIndex = index - (aSamples << 16);

	// return sample byte count and setup output buffer

	aDstBuffer.Data().SetLength(length * 2); //adjust length of destination buffer

	return (length);

	}

TUint CMMFStereoToMonoRateConverter::MaxConvertBufferSize(TUint aSrcBufferSize)

	{

	TUint size = aSrcBufferSize/2;

	size += aSrcBufferSize & 1; //avoid round down error

	return size;

	}

//This method takes the left and right sample of interleaved PCM and sums it, then divides by 2

TInt CMMFStereoToMonoConverter::Convert(const CMMFDataBuffer& aSrcBuffer, CMMFDataBuffer& aDstBuffer)

	{

	TInt16* aSrc = (TInt16*)aSrcBuffer.Data().Ptr();

	TInt16* aDst = (TInt16*)aDstBuffer.Data().Ptr();

	TUint aSamples = aSrcBuffer.Data().Length()/4;

	for (TUint i=0;i<aSamples;i++)

		{

		*aDst++ = (TInt16)((aSrc[0] + (aSrc[1])) / 2);

		aSrc+=2;

		}

	aDstBuffer.Data().SetLength(aSamples*2); //adjust length of destination buffer

	return aSamples*2;

	}	

TUint CMMFStereoToMonoConverter::MaxConvertBufferSize(TUint aSrcBufferSize)

	{

	TUint size = aSrcBufferSize/2;

	size += aSrcBufferSize & 1; //avoid round down error

	return size;

	}

TInt CMMFMonoToStereoConverter::Convert(const CMMFDataBuffer& aSrcBuffer, CMMFDataBuffer& aDstBuffer)

	{

	TInt16* aSrc = (TInt16*)aSrcBuffer.Data().Ptr();

	TInt16* aDst = (TInt16*)aDstBuffer.Data().Ptr();

	TUint aSamples = aSrcBuffer.Data().Length()/2;

	for (TUint i=0;i<aSamples;i++)

		{

		*aDst++ = *aSrc;

		*aDst++ = *aSrc++;

		}

	aDstBuffer.Data().SetLength(aSamples*4); //adjust length of destination buffer

	return aSamples*4;

	}	

TUint CMMFMonoToStereoConverter::MaxConvertBufferSize(TUint aSrcBufferSize)

	{

	return aSrcBufferSize*2;

	}