/*

* Copyright (c) 2002-2004 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:  ?Description

*

*/

// INCLUDE FILES

#include <e32std.h>

#include "Base64.h"

// LOCAL CONSTANTS AND MACROS

LOCAL_C const TUint8* const KBase64Chars =

    _S8("ABCDEFGHIJKLMNOPQRSTUVWXYZ"

    "abcdefghijklmnopqrstuvwxyz"

    "0123456789+/");

// LOCAL FUNCTION PROTOTYPES

LOCAL_C TUint8 FindBase64Char(

    TUint aChar);

// ============================= LOCAL FUNCTIONS ===============================

// -----------------------------------------------------------------------------

// ?function_name ?description.

// ?description

// Returns: ?value_1: ?description

//          ?value_n: ?description_line1

//                    ?description_line2

// -----------------------------------------------------------------------------

//

LOCAL_C TUint8 FindBase64Char(

    TUint aChar)

    {

    TUint8 i;

    for (i = 0; i < 64; i++)

        {

        if (aChar == KBase64Chars[i]) break;

        }

    return i;

    }

// ========================== OTHER EXPORTED FUNCTIONS =========================

// -----------------------------------------------------------------------------

// ?function_name implements...

// ?implementation_description.

// Returns: ?value_1: ?description

//          ?value_n: ?description

//                    ?description

// -----------------------------------------------------------------------------

//

EXPORT_C HBufC8* Base64EncodeL(

    const TDesC8& aInput)

    {

    HBufC8* ret;

    TInt i = 0;

    TInt j = 0;

    TUint8 charArray3[3];

    TUint8 charArray4[4];

    TInt l = 0;

    ret = HBufC8::NewL((aInput.Length() * 4 + 1) / 3);

    TPtr8 des = ret->Des();

    while (l < aInput.Length())

        {

        charArray3[i++] = aInput[l];

        l++;

        if (i == 3)

            {

            charArray4[0] = static_cast<TUint8>((charArray3[0] & 0xfc) >> 2);

            charArray4[1] = static_cast<TUint8>(

                ((charArray3[0] & 0x03) << 4) + ((charArray3[1] & 0xf0) >> 4));

            charArray4[2] = static_cast<TUint8>(

                ((charArray3[1] & 0x0f) << 2) + ((charArray3[2] & 0xc0) >> 6));

            charArray4[3] = static_cast<TUint8>(charArray3[2] & 0x3f);

            for (i = 0; i <4; i++)

                {

                des.Append(KBase64Chars[charArray4[i]]);

                }

            i = 0;

            }

        }

    if (i != 0)

        {

        for (j = i; j < 3; j++)

            {

            charArray3[j] = '\0';

            }

        charArray4[0] = static_cast<TUint8>((charArray3[0] & 0xfc) >> 2);

        charArray4[1] = static_cast<TUint8>(

            ((charArray3[0] & 0x03) << 4) +((charArray3[1] & 0xf0) >> 4));

        charArray4[2] = static_cast<TUint8>(

            ((charArray3[1] & 0x0f) << 2) +((charArray3[2] & 0xc0) >> 6));

        charArray4[3] = static_cast<TUint8>(charArray3[2] & 0x3f);

        for (j = 0; j < i + 1; j++)

            {

            des.Append(KBase64Chars[charArray4[j]]);

            }

        while ((i++ < 3))

            {

            des.Append('=');

            }

        }

    return ret;

    }

// -----------------------------------------------------------------------------

// ?function_name implements...

// ?implementation_description.

// Returns: ?value_1: ?description

//          ?value_n: ?description

//                    ?description

// -----------------------------------------------------------------------------

//

EXPORT_C HBufC8* Base64DecodeL(

    const TDesC8& aInput)

    {

    TInt len = aInput.Length();

    TInt i = 0;

    TInt j = 0;

    TInt in = 0;

    TUint8 charArray4[4], charArray3[3];

    HBufC8* ret;

    ret = HBufC8::NewL((aInput.Length() * 3 + 1) / 4);

    TPtr8 des = ret->Des();

    while (len-- && aInput[in] != '=')

        {

        if (FindBase64Char(aInput[in]) < 64)

            {

            charArray4[i++] = aInput[in]; in++;

            }

        else

            {

            in++;

            }

        if (i == 4)

            {

            for (i = 0; i < 4; i++)

                {

                charArray4[i] = FindBase64Char(charArray4[i]);

                }

            charArray3[0] = static_cast<TUint8>(

                (charArray4[0] << 2) + ((charArray4[1] & 0x30) >> 4));

            charArray3[1] = static_cast<TUint8>(

                ((charArray4[1] & 0xf) << 4) + ((charArray4[2] & 0x3c) >> 2));

            charArray3[2] = static_cast<TUint8>(

            ((charArray4[2] & 0x3) << 6) + charArray4[3]);

            for (i = 0; i < 3; i++)

                {

                des.Append(charArray3[i]);

                }

            i = 0;

            }

        }

    if (i != 0)

        {

        for (j = i; j < 4; j++)

            {

            charArray4[j] = 0;

            }

        for (j = 0; j < 4; j++)

            {

            charArray4[j] = FindBase64Char(charArray4[j]);

            }

        charArray3[0] = static_cast<TUint8>(

            (charArray4[0] << 2) + ((charArray4[1] & 0x30) >> 4));

        charArray3[1] = static_cast<TUint8>(

            ((charArray4[1] & 0xf) << 4) + ((charArray4[2] & 0x3c) >> 2));

        charArray3[2] = static_cast<TUint8>(

            ((charArray4[2] & 0x3) << 6) + charArray4[3]);

        for (j = 0; j < i - 1; j++)

            {

            des.Append(charArray3[j]);

            }

        }

    return ret;

    }

//  End of File