// 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.

 @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);

 	IMPORT_C TInt PortableEncode(const TDesC8& aSrcString, TDes8& aDestString, TInt aLineLength=-1);

 private:

 	TInt iShiftStored;

 	TInt iMaskShiftStored;	

 	};

 #endif	// __TCONVBASE64_H__