// 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:

//

#include "mmfpcmS16PcmS8HwDevice.h"

/**

 *

 *	Returns the created hw device for passing audio through audio.

 *  for the wins implementation this would always be pcm16 although

 *  this is effectively a null hw device that will pass any datatype through

 *	@return	"CMMFPcm16ToPcmU16BEHwDevice"

 *

 */

CMMFPcmS16ToPcmS8HwDevice* CMMFPcmS16ToPcmS8HwDevice::NewL()

	{

    CMMFPcmS16ToPcmS8HwDevice* self = new (ELeave) CMMFPcmS16ToPcmS8HwDevice();

	CleanupStack::PushL(self);

	self->ConstructL();

	CleanupStack::Pop(self);

	return self;

	}

/**

*

* ~CMMFPcmS16ToPcmS8HwDevice

*/

CMMFPcmS16ToPcmS8HwDevice::~CMMFPcmS16ToPcmS8HwDevice()

	{

	}

/**

*

* ConstructL

*

*/

void CMMFPcmS16ToPcmS8HwDevice::ConstructL()

	{

	iCodec = new (ELeave) CMMFPcmS16ToPcmS8Codec();

	}

/**

*

* Codec

* @return 'CMMFSwCodec&'

*

*/

CMMFSwCodec& CMMFPcmS16ToPcmS8HwDevice::Codec()

	{

	return *iCodec;

	}

/**

*

* ProcessL

* @param aSrc

* @param aDst

* @param aSamples

*

*/

CMMFSwCodec::TCodecProcessResult CMMFPcmS16ToPcmS8Codec::ProcessL(const CMMFBuffer& aSrc, CMMFBuffer& aDst)

	{

	TCodecProcessResult result;

	result.iCodecProcessStatus = TCodecProcessResult::EProcessComplete;

	//convert from generic CMMFBuffer to CMMFDataBuffer

	const CMMFDataBuffer* src = STATIC_CAST(const CMMFDataBuffer*, &aSrc);

	CMMFDataBuffer* dst = STATIC_CAST(CMMFDataBuffer*, &aDst);

	//[Check Preconditions]

	if( !CheckPreconditions( src, dst ))

		{

		//[ precondition violation ]

		User::Leave( KErrArgument );

		}

	//we need to cast away CONST even on the source, as the TClass needs a TUint8*

	TUint8* pSrc = CONST_CAST(TUint8*,src->Data().Ptr());

	TUint8* pDst = CONST_CAST(TUint8*,dst->Data().Ptr());

	TInt srcUse = src->Data().Length();

	TInt noSamples = srcUse/2;

	//compress TWO bytes (16-bit PCM word) into a to 1 byte sample

	iAudioPcmS16ToPcmS8.Convert(pSrc, pDst, noSamples );

	result.iCodecProcessStatus = TCodecProcessResult::EProcessComplete;

	result.iSrcBytesProcessed  = srcUse;

	result.iDstBytesAdded      = srcUse/2;

	dst->Data().SetLength(result.iDstBytesAdded);

	//[ post conditions

    // srcbytes/2 == destbytes added

	// pos src == 0

	// pos dest == 0 ]

	__ASSERT_DEBUG( (src->Position() == 0), TMmfAudioCodecPanicsNameSpace::Panic( 	TMmfAudioCodecPanicsNameSpace::EPostConditionViolation ));

	__ASSERT_DEBUG( (dst->Position() == 0), TMmfAudioCodecPanicsNameSpace::Panic( 	TMmfAudioCodecPanicsNameSpace::EPostConditionViolation ));

	__ASSERT_DEBUG( src->Data().Length()/2 == dst->Data().Length(), TMmfAudioCodecPanicsNameSpace::Panic( 	TMmfAudioCodecPanicsNameSpace::EPostConditionViolation ));

	return result;

	}

/**

*

* Preconditions

* This methos tests the preconditions of the ProcessL method

* @return TBool ETrue for sucess and EFalse for failure of the preconditions

*

**/

TBool CMMFPcmS16ToPcmS8Codec::CheckPreconditions( const CMMFDataBuffer* aSrcBuffer, CMMFDataBuffer* aDestBuffer )

	{

	TBool result = EFalse;

	if(! aSrcBuffer )

		{

		return result;

		}

	if( ! aDestBuffer )

		{

		return result;

		}

	// Check position of src and dest are 0

	if( aSrcBuffer->Position() )

		{

		return result;

		}

	// Check position of src and dest are 0

	if( aDestBuffer->Position() )

		{

		return result;

		}

	// check there are sufficient bytes in the output to consume the input

	if( ( aSrcBuffer->Data().Length()/2 > aDestBuffer->Data().MaxLength() ) &&

		( aSrcBuffer->Data().Length() % 2 == 0 ) ) // must have pcm16 samples on input

		{

		return result;

		}

	result = ETrue;  // preconditions have been satisfied

	return result;

	}