// Copyright (c) 2001-2009 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:

// File contains internal classes for Ascii To Base64 converison

// and vice-versa.

// 

//

/**

 @file TConvBase64.h

 @internalAll

 @released

*/

#ifndef __TCONVBASE64_H__

#define __TCONVBASE64_H__

#include <e32base.h>

const TInt KMaxB64EncodedCharsPerLine = 60;

// Could be increased to 75 characters for every encoded line if KDecodeLineLength = 675.  

// 60 was chosen to maintain existing behaviour.

const TInt8 KImcvLookUpStartOffset = 43;

const TUint8 KImcvConvEquals = '=';

const TInt8 AsciiToBase64[80]=

	{

    62, -1, -1, -1, 63, 52, 53, 54, 55, 56,

    57, 58, 59, 60, 61, -1, -1, -1, 64, -1,

    -1, -1,  0,  1,  2,  3,  4,  5,  6,  7,

    8,  9, 10, 11, 12, 13, 14, 15, 16, 17,

    18, 19, 20, 21, 22, 23, 24, 25, -1, -1,

    -1, -1, -1, -1, 26, 27, 28, 29, 30, 31,

    32, 33, 34, 35, 36, 37, 38, 39, 40, 41,

    42, 43, 44, 45, 46, 47, 48, 49, 50, 51

    };

const TInt8 Base64ToAscii[65]=

	{

    65, 66, 67, 68, 69, 70, 71, 72, 73, 74,

    75, 76, 77, 78, 79, 80, 81, 82, 83, 84,

    85, 86, 87, 88, 89, 90, 97, 98, 99,100,

    101,102,103,104,105,106,107,108,109,110,

    111,112,113,114,115,116,117,118,119,120,

    121,122, 48, 49, 50, 51, 52, 53, 54, 55,

    56, 57, 43, 47, 61 

    };

/**

Base64 encoding and decoding class, complaint with RFC-3548.

@internalAll

@released

*/    

class TBase64

	{

private:

	/** 

		enum base64 coding defines 

	*/

	enum

	{ 

	/** Padding characters	*/

	EPadChar = 64 

	};

	/** 

	enum for EMaskValues

	*/

	enum EMaskValues

	{ 

	/**	Mask Six bits */

	ESixBitMask = 0x3F, 

	/** Mask Eight bits */

	EEightBitMask = 0xFF 

	};

	/** 

	enum for EMaskShiftValues

	*/

	enum EMaskShiftValues

	{ 

	/** enum for 6 	*/

	ESix = 6,

	/** enum for 4 	*/ 

	EFour = 4, 

	/** enum for 2	*/

	ETwo = 2, 

	/** enum for 0	*/

	EZero = 0 

	};

public:

	IMPORT_C TBase64();

	IMPORT_C TInt Encode( const TDesC8& aSrcString, TDes8& rDestString);

	IMPORT_C TBool Decode( const TDesC8& aSrcString, TDes8& rDestString);

private:

	TInt iShiftStored;

	TInt iMaskShiftStored;	

	};

#endif	// __TCONVBASE64_H__