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* Software License Agreement (BSD License)
*
*  Copyright (c) 2010, LABUST, UNIZG-FER
*  All rights reserved.
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*     notice, this list of conditions and the following disclaimer.
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*     disclaimer in the documentation and/or other materials provided
*     with the distribution.
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#include <labust/xml/Base64Decoder.hpp>

#include <iostream>
#include <vector>

namespace labust
{
    namespace xml
    {
        std::vector<char> Base64_decode(std::string const& encoded_string)
        {
		static const std::string base64_chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
            int in_len = encoded_string.size();
            int i = 0;
            int j = 0;
            int in_ = 0;
            unsigned char char_array_4[4], char_array_3[3];
				std::vector<char> decoded;

            while (in_len-- && (encoded_string[in_] != '=') && is_base64(encoded_string[in_]))
            {
                char_array_4[i++] = encoded_string[in_];
                in_++;
                if (i == 4)
                {
                    for (i = 0; i < 4; i++)
                        char_array_4[i] = base64_chars.find(char_array_4[i]);

                    char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
                    char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
                    char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];

                    for (i = 0; (i < 3); i++)
                    {
			decoded.push_back(char_array_3[i]);                     
                    }
                    i = 0;
                }
            }

            if (i)
            {
                for (j = i; j < 4; j++)
                    char_array_4[j] = 0;

                for (j = 0; j < 4; j++)
                    char_array_4[j] = base64_chars.find(char_array_4[j]);

                char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
                char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
                char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];

                for (j = 0; (j < i - 1); j++)
                {
                    decoded.push_back(char_array_3[j]);
                }
            }
            return decoded;
        }
    }
}

