// lexer.h

// 

// Copyright (c) 2006 - 2010 Accenture. All rights reserved.

// This component and the accompanying materials are made available

// under the terms of the "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:

// Accenture - Initial contribution

//

#ifndef __LEXER_H__

#define __LEXER_H__

#include <e32base.h>

#include <fshell/iocli.h>

class CLex;

class CReservedLookup;

class TToken

	{

public:

	enum TType

		{

		ENull,

		EString,

		EPipe,

		EDoublePipe,

		ERedirectStdinFromFile,

		ERedirectStdoutToFile,

		ERedirectStdoutToFileAppend,

		ERedirectStdoutToStderr,

		ERedirectStderrToFile,

		ERedirectStderrToFileAppend,

		ERedirectStderrToStdout,

		EAmpersand,

		EDoubleAmpersand,

		EAmpersandPipe,

		ENewLine,

		ESemicolon,

		EVariable

		};

public:

	TToken();

	TToken(TType aType, const TDesC& aToken, TInt aPos);

	TToken& operator=(const TToken& aToken);

	TType Type() const;

	TInt Position() const;

	const TDesC& String() const;

private:

	TType iType;

	TPtrC iToken;

	TInt iPos;

	};

class CLexer : public CBase

	{

public:

	enum TBehaviour

		{

		EHandleSingleQuotes	= 0x00000001,	///< Causes text within single quotes to be reported as a single TToken::EString type token.

		EHandleDoubleQuotes	= 0x00000002,	///< Causes text within double quotes to be reported as a single TToken::EString type token.

		EHandleComments		= 0x00000004	///< Causes text following a '#' until the end of the line to be discarded.

		};

public:

	static CLexer* NewL();

	static CLexer* NewL(TUint aBehaviour);

	static CLexer* NewLC();

	static CLexer* NewLC(TUint aBehaviour);

	~CLexer();

	void DefineTokenTypeL(TToken::TType aTokenType, const TDesC& aString);

	void Set(const TDesC& aDes, const TChar& aEscapeChar);

	void Set(RIoReadHandle& aHandle, const TChar& aEscapeChar);

	void Purge();

	void SkipToEnd();

	TToken NextTokenL();

	TInt CurrentOffset() const;

	TBool MoreL();

	const TUint16* Ptr() const;

private:

	CLexer(TUint aBehaviour);

	void ConstructL();

	void SkipSingleQuotedCharsL();

	void SkipDoubleQuotedCharsL();

	void SkipCommentL();

	void SkipWhiteSpaceL();

private:

	TUint iBehaviour;

	TChar iEscapeChar;

	CLex* iLex;

	CReservedLookup* iReservedLookup;

	};

#endif // __LEXER_H__