/*

* Copyright (c) 1998-2009 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: 

* Header for the classes that import and export plain text into and out of ETEXT.

*

*/

#ifndef __TXTPLAIN__

#define __TXTPLAIN__ 1

#include <e32std.h>

#include <s32mem.h>

#include <txtetext.h>

#include "TxtWriter.h"

class CCnvCharacterSetConverter;

class TPlainTextIOState;

NONSHARABLE_CLASS(CPlainTextConverter) : public CBase

/**

@internalComponent

*/

	{

	public:

	static CPlainTextConverter* NewLC();

	~CPlainTextConverter();

	void PrepareToConvertL(TPlainTextIOState& aState,const TDesC8* aSample);

	enum

		{

		EConversionBufferSize = 1024

		};

	CCnvCharacterSetConverter* iConverter;	// use this converter to translate input or output

	TUint8* iConversionBuffer;				// the buffer used by iConverter for non-Unicode text

	TInt iConversionBufferLength;			// current number of characters in the conversion buffer

	};

class TPlainTextIOState

/**

@internalComponent

*/

	{

	public:

	TPlainTextIOState(const CPlainText::TImportExportParam& aParam,CPlainText::TImportExportResult& aResult,

					  RWriteStream& aOutput,RReadStream& aInput);

	TBool Finished() const

		{ return iResult.iOutputChars >= iParam.iMaxOutputChars || iResult.iInputChars >= iParam.iMaxInputChars; }

	TText ReadRawCharL();

	void WriteRawCharL(TText aChar);

	const CPlainText::TImportExportParam& iParam;

	CPlainText::TImportExportResult& iResult;

	RWriteStream& iOutput;

	RReadStream& iInput;

	CPlainTextConverter* iConverter;// if non-null, use CHARCONV, via this object, to convert a

									// foreign encoding to or from Unicode

	TBool iSwapInput;				// input needs to be byte-swapped

	TBool iCheckByteOrder;			// flip iSwapInput if the next input character is 0xFFFE (byte-swapped byte order mark)

	};

class TPlainTextWriter: public TPlainTextIOState

/**

@internalComponent

*/

	{

	public:

	static void TranslateL(const CPlainText::TImportExportParam& aParam,CPlainText::TImportExportResult& aResult,

						   RWriteStream& aOutput,RReadStream& aInput);

	private:

	TPlainTextWriter(const CPlainText::TImportExportParam& aParam,CPlainText::TImportExportResult& aResult,

					 RWriteStream& aOutput,RReadStream& aInput);

	void TranslateHelperL();

	enum

		{

		EDefaultLineBufferSize = CPlainTextConverter::EConversionBufferSize * 2

		};

	void TranslateToEofL();

	void FlushL();

	void WriteCharL(TText aChar);

	void WriteNewLineL();

	void WriteAndConvertL(const TText* aText,TInt aLength);

	RBufReadStream iBufReadStream;	// a stream over the input buffer

	TInt iMaxLineLength;			// wrap lines automatically if they exceed this length

	TInt iLineLength;				// length of the current line

	TText* iLineBuffer;				// if non-null, this buffer contains the current line, or Unicode text

									// to be converted to a foreign encoding

	TInt iMaxLineBufferLength;		// maximum number of characters in iLineBuffer

	};

/**

@internalComponent

*/

NONSHARABLE_CLASS(TPlainTextReader) : public TPlainTextIOState, public MOutputChar

	{

	public:

	static void TranslateL(const CPlainText::TImportExportParam& aParam,CPlainText::TImportExportResult& aResult,

						   RWriteStream& aOutput,RReadStream& aInput);

	private:

	TPlainTextReader(const CPlainText::TImportExportParam& aParam,CPlainText::TImportExportResult& aResult,

					 RWriteStream& aOutput,RReadStream& aInput);

	void TranslateHelperL(TSLBTransaltor& aSLBTranslator);

	enum

		{

		EInputBufferSize = CPlainTextConverter::EConversionBufferSize * 2

		};

	void TranslateToEofL(TSLBTransaltor& aSLBTranslator);

	TText ReadAndConvertL();

	virtual void OutputCharL(TText aChar);

	TText* iInputBuffer;				// if non-null, this buffer contains Unicode text

										// converted from a foreign encoding

	TInt iInputLength;					// number of characters currently stored in iInputBuffer

	TInt iInputPos;						// current position in iInputBuffer;

	TInt iConversionState;				// state used by iConverter when converting to Unicode

	};

#endif // __TXTPLAIN__