/*

* Copyright (c) 2005-2009 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: 

* J5 charconv character converter

* converts from EUC_JP to unicode

* based on code in EUCJP_PACKED

*

*/

#include <e32std.h>

#include <charconv.h>

#include <ecom/implementationproxy.h>

#include <convutils.h>

#include "shiftjis.h"

#include "jisbase.h"

#include "jisx0201.h"

#include "jisx0208.h"

#include "jisx0212.h"

const TUint KSingleShift2=0x8e;

const TUint KSingleShift3=0x8f;

#if defined(_DEBUG)

_LIT(KLitPanicText, "EUCJP_PACKED");

enum TPanic

	{

	EPanicNothingToConvert1=1,

	EPanicNothingToConvert2,

	EPanicNothingToConvert3,

	EPanicNothingToConvert4,

	EPanicNothingToConvert5,

	EPanicNothingToConvert6,

	EPanicOddNumberOfBytes1,

	EPanicOddNumberOfBytes2,

	EPanicOddNumberOfBytes3,

	EPanicOddNumberOfBytes4,

	EPanicOddNumberOfBytes5,

	EPanicOddNumberOfBytes6,

	EPanicBadHighBit1,

	EPanicBadHighBit2,

	EPanicBadHighBit3,

	EPanicBadHighBit4,

	EPanicBadHighBit5,

	EPanicBadHighBit6,

	EPanicBadHighBit7,

	EPanicBadPointers1,

	EPanicBadPointers2,

	EPanicBadPointers3,

	EPanicBadPointers4,

	EPanicBadPointers5,

	EPanicBadPointers6,

	EPanicBadPointers7,

	EPanicBadPointers8,

	EPanicBadPointers9,

	EPanicBadPointers10,

	EPanicBadPointers11,

	EPanicBadPointers12,

	EPanicBadPointers13,

	EPanicBadPointers14,

	EPanicBadPointers15,

	EPanicBadPointers16,

	EPanicBadPointers17,

	EPanicBadPointers18,

	EPanicBadPointers19,

	EPanicBadPointers20,

	EPanicBadPointers21,

	EPanicBadPointers22,

	EPanicBadPointers23,

	EPanicBadPointers24,

	EPanicBadPointers25,

	EPanicBadPointers26,

	EPanicBadPointers27,

	EPanicBadPointers28,

	EPanicBadPointers29,

	EPanicBadPointers30,

	EPanicBadPointers31,

	EPanicBadPointers32,

	EPanicBadPointers33,

	EPanicBadPointers34,

	EPanicBadPointers35,

	EPanicBadPointers36,

	EPanicBadCalculation1,

	EPanicBadCalculation2,

	EPanicNumberOfBytesIsNotMultipleOfThree1,

	EPanicNumberOfBytesIsNotMultipleOfThree2,

	EPanicSingleShift2Expected,

	EPanicSingleShift3Expected

	};

LOCAL_C void Panic(TPanic aPanic)

	{

	User::Panic(KLitPanicText, aPanic);

	}

#endif

/**

 @return The number of bytes that can be converted from aDescriptor to JisRoman

 @internalTechnology 

 */

TInt NumberOfBytesAbleToConvertToJisRoman(const TDesC8& aDescriptor)

	{

	const TUint8* pointerToPreviousByte=aDescriptor.Ptr()-1;

	const TUint8* const pointerToLastByte=pointerToPreviousByte+aDescriptor.Length();

	if (pointerToPreviousByte==pointerToLastByte)

		{

		return 0;

		}

	FOREVER

		{

		__ASSERT_DEBUG(pointerToPreviousByte<pointerToLastByte, Panic(EPanicBadPointers14));

		const TUint currentByte=*(pointerToPreviousByte+1);

		if (currentByte&0x80)

			{

			break;

			}

		__ASSERT_DEBUG(pointerToPreviousByte<pointerToLastByte, Panic(EPanicBadPointers15));

		++pointerToPreviousByte;

		__ASSERT_DEBUG(pointerToPreviousByte<=pointerToLastByte, Panic(EPanicBadPointers16));

		if (pointerToPreviousByte>=pointerToLastByte)

			{

			break;

			}

		}

	return (pointerToPreviousByte+1)-aDescriptor.Ptr();

	}

/**

 @return The number of bytes that can be converted from aDescriptor to Jis X208

 @internalTechnology 

 */

 TInt NumberOfBytesAbleToConvertToJisX0208(const TDesC8& aDescriptor)

	{

	const TUint8* pointerToPreviousByte=aDescriptor.Ptr()-1;

	const TUint8* const pointerToLastByte=pointerToPreviousByte+aDescriptor.Length();

	if (pointerToPreviousByte==pointerToLastByte)

		{

		return 0;

		}

	FOREVER

		{

		__ASSERT_DEBUG(pointerToPreviousByte<pointerToLastByte, Panic(EPanicBadPointers17));

		TUint currentByte=*(pointerToPreviousByte+1);

		if (currentByte<0xa0)

			{

			break;

			}

		__ASSERT_DEBUG(pointerToPreviousByte<pointerToLastByte, Panic(EPanicBadPointers18));

		if (pointerToLastByte-pointerToPreviousByte<2)

			{

			break;

			}

		++pointerToPreviousByte;

		currentByte=*(pointerToPreviousByte+1);

		if (currentByte<0xa0)

			{

			return CCnvCharacterSetConverter::EErrorIllFormedInput;

			}

		__ASSERT_DEBUG(pointerToPreviousByte<pointerToLastByte, Panic(EPanicBadPointers19));

		++pointerToPreviousByte;

		__ASSERT_DEBUG(pointerToPreviousByte<=pointerToLastByte, Panic(EPanicBadPointers20));

		if (pointerToPreviousByte>=pointerToLastByte)

			{

			break;

			}

		}

	return (pointerToPreviousByte+1)-aDescriptor.Ptr();

	}

/**

 @return The number of bytes that can be converted from aDescriptor to HalfWidthKatakana

 @internalTechnology 

 */

 TInt NumberOfBytesAbleToConvertToHalfWidthKatakana8(const TDesC8& aDescriptor)

	{

	const TUint8* pointerToPreviousByte=aDescriptor.Ptr()-1;

	const TUint8* const pointerToLastByte=pointerToPreviousByte+aDescriptor.Length();

	if (pointerToPreviousByte==pointerToLastByte)

		{

		return 0;

		}

	FOREVER

		{

		__ASSERT_DEBUG(pointerToPreviousByte<pointerToLastByte, Panic(EPanicBadPointers21));

		TUint currentByte=*(pointerToPreviousByte+1);

		if (currentByte!=KSingleShift2)

			{

			break;

			}

		__ASSERT_DEBUG(pointerToPreviousByte<pointerToLastByte, Panic(EPanicBadPointers22));

		if (pointerToLastByte-pointerToPreviousByte<2)

			{

			break;

			}

		++pointerToPreviousByte;

		currentByte=*(pointerToPreviousByte+1);

		if (currentByte<0xa0)

			{

			return CCnvCharacterSetConverter::EErrorIllFormedInput;

			}

		__ASSERT_DEBUG(pointerToPreviousByte<pointerToLastByte, Panic(EPanicBadPointers23));

		++pointerToPreviousByte;

		__ASSERT_DEBUG(pointerToPreviousByte<=pointerToLastByte, Panic(EPanicBadPointers24));

		if (pointerToPreviousByte>=pointerToLastByte)

			{

			break;

			}

		}

	return (pointerToPreviousByte+1)-aDescriptor.Ptr();

	}

/**

 @return The number of bytes that can be converted from aDescriptor to JISX0212

 @internalTechnology 

 */

TInt NumberOfBytesAbleToConvertToJisX0212(const TDesC8& aDescriptor)

	{

	const TUint8* pointerToPreviousByte=aDescriptor.Ptr()-1;

	const TUint8* const pointerToLastByte=pointerToPreviousByte+aDescriptor.Length();

	if (pointerToPreviousByte==pointerToLastByte)

		{

		return 0;

		}

	FOREVER

		{

		__ASSERT_DEBUG(pointerToPreviousByte<pointerToLastByte, Panic(EPanicBadPointers25));

		TUint currentByte=*(pointerToPreviousByte+1);

		if (currentByte!=KSingleShift3)

			{

			break;

			}

		__ASSERT_DEBUG(pointerToPreviousByte<pointerToLastByte, Panic(EPanicBadPointers26));

		if (pointerToLastByte-pointerToPreviousByte<3)

			{

			break;

			}

		++pointerToPreviousByte;

		currentByte=*(pointerToPreviousByte+1);

		if (currentByte<0xa0)

			{

			return CCnvCharacterSetConverter::EErrorIllFormedInput;

			}

		__ASSERT_DEBUG(pointerToPreviousByte<pointerToLastByte, Panic(EPanicBadPointers27));

		++pointerToPreviousByte;

		currentByte=*(pointerToPreviousByte+1);

		if (currentByte<0xa0)

			{

			return CCnvCharacterSetConverter::EErrorIllFormedInput;

			}

		__ASSERT_DEBUG(pointerToPreviousByte<pointerToLastByte, Panic(EPanicBadPointers28));

		++pointerToPreviousByte;

		__ASSERT_DEBUG(pointerToPreviousByte<=pointerToLastByte, Panic(EPanicBadPointers29));

		if (pointerToPreviousByte>=pointerToLastByte)

			{

			break;

			}

		}

	return (pointerToPreviousByte+1)-aDescriptor.Ptr();

	}

void DummyConvertToIntermediateBufferInPlace(TDes8&)

	{

	}

/**

 Converts to JISX0212

 @internalTechnology 

 */

void ConvertToJisX0212FromEucJpPackedInPlace(TDes8& aDescriptor)

	{

	const TInt descriptorLength=aDescriptor.Length();

	__ASSERT_DEBUG(descriptorLength>0, Panic(EPanicNothingToConvert6));

	__ASSERT_DEBUG(descriptorLength%3==0, Panic(EPanicNumberOfBytesIsNotMultipleOfThree2));

	TUint8* pointerToTargetByte=CONST_CAST(TUint8*, aDescriptor.Ptr());

	const TUint8* pointerToSourceByte=pointerToTargetByte;

	const TUint8* const pointerToLastByte=pointerToSourceByte+(descriptorLength-1);

	FOREVER

		{

		__ASSERT_DEBUG(*pointerToSourceByte==KSingleShift3, Panic(EPanicSingleShift3Expected));

		__ASSERT_DEBUG(pointerToSourceByte<pointerToLastByte, Panic(EPanicBadPointers33));

		++pointerToSourceByte;

		TUint sourceByte=*pointerToSourceByte;

		__ASSERT_DEBUG(sourceByte&0x80, Panic(EPanicBadHighBit6));

		*pointerToTargetByte=STATIC_CAST(TUint8, sourceByte&~0x80);

		__ASSERT_DEBUG(pointerToSourceByte<pointerToLastByte, Panic(EPanicBadPointers34));

		++pointerToSourceByte;

		sourceByte=*pointerToSourceByte;

		__ASSERT_DEBUG(sourceByte&0x80, Panic(EPanicBadHighBit7));

		__ASSERT_DEBUG(pointerToTargetByte<pointerToLastByte, Panic(EPanicBadPointers35));

		++pointerToTargetByte;

		*pointerToTargetByte=STATIC_CAST(TUint8, sourceByte&~0x80);

		__ASSERT_DEBUG(pointerToSourceByte<=pointerToLastByte, Panic(EPanicBadPointers36));

		if (pointerToSourceByte>=pointerToLastByte)

			{

			break;

			}

		++pointerToSourceByte;

		++pointerToTargetByte;

		}

	aDescriptor.SetLength((descriptorLength/3)*2);

	}

/**

 Converts to JISX0208

 @internalTechnology 

 */

void ConvertToJisX0208FromEucJpPackedInPlace(TDes8& aDescriptor)

	{

	const TInt descriptorLength=aDescriptor.Length();

	__ASSERT_DEBUG(descriptorLength>0, Panic(EPanicNothingToConvert4));

	__ASSERT_DEBUG(descriptorLength%2==0, Panic(EPanicOddNumberOfBytes5));

	TUint8* pointerToCurrentByte=CONST_CAST(TUint8*, aDescriptor.Ptr());

	const TUint8* const pointerToLastByte=pointerToCurrentByte+(descriptorLength-1);

	FOREVER

		{

		const TUint currentByte=*pointerToCurrentByte;

		__ASSERT_DEBUG(currentByte&0x80, Panic(EPanicBadHighBit4));

		*pointerToCurrentByte=STATIC_CAST(TUint8, currentByte&~0x80);

		__ASSERT_DEBUG(pointerToCurrentByte<=pointerToLastByte, Panic(EPanicBadPointers30));

		if (pointerToCurrentByte>=pointerToLastByte)

			{

			break;

			}

		++pointerToCurrentByte;

		}

	}

/**

 Converts to Half Width Katakana

 @internalTechnology 

 */

void ConvertToHalfWidthKatakana8FromEucJpPackedInPlace(TDes8& aDescriptor)

	{

	const TInt descriptorLength=aDescriptor.Length();

	__ASSERT_DEBUG(descriptorLength>0, Panic(EPanicNothingToConvert5));

	__ASSERT_DEBUG(descriptorLength%2==0, Panic(EPanicOddNumberOfBytes6));

	TUint8* pointerToTargetByte=CONST_CAST(TUint8*, aDescriptor.Ptr());

	const TUint8* pointerToSourceByte=pointerToTargetByte;

	const TUint8* const pointerToLastByte=pointerToSourceByte+(descriptorLength-1);

	FOREVER

		{

		__ASSERT_DEBUG(*pointerToSourceByte==KSingleShift2, Panic(EPanicSingleShift2Expected));

		__ASSERT_DEBUG(pointerToSourceByte<pointerToLastByte, Panic(EPanicBadPointers31));

		++pointerToSourceByte;

		const TUint sourceByte=*pointerToSourceByte;

		__ASSERT_DEBUG(sourceByte&0x80, Panic(EPanicBadHighBit5));

		*pointerToTargetByte=STATIC_CAST(TUint8, sourceByte);

		__ASSERT_DEBUG(pointerToSourceByte<=pointerToLastByte, Panic(EPanicBadPointers32));

		if (pointerToSourceByte>=pointerToLastByte)

			{

			break;

			}

		++pointerToSourceByte;

		++pointerToTargetByte;

		}

	aDescriptor.SetLength(descriptorLength/2);

	}