// 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;

 	}