base64.hpp

/*
  ANCH Framework: ANother C++ Hack is a C++ framework based on C++11 standard
  Copyright (C) 2012 Vincent Lachenal

  This file is part of ANCH Framework.

  ANCH Framework is free software: you can redistribute it and/or modify
  it under the terms of the GNU Lesser General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.

  ANCH Framework is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public License
  along with ANCH Framework.  If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef _ANCH_CRYPTO_B2T_BASE64_H_
#define _ANCH_CRYPTO_B2T_BASE64_H_

#include <iostream>
#include <sstream>

#include <string.h>

namespace anch {
  namespace crypto {

    class Base64 {
      // Attributes +
    private:
      const static char _alphabet[];

      const static char _padding;
      // Attributes -

      // Constructors +
    private:
      Base64();
      // Constructors -

      // Destructor +
    public:
      virtual ~Base64();
      // Destructor -


      // Encoding methods +
    public:
      template<class CharT, class Traits>
      static void encode(std::basic_istream<CharT,Traits>& data,
                         std::basic_ostream<CharT,Traits>& output)
        noexcept {
        if(data) {
          char buffer[1024];
          while(!data.eof()) {
            data.read(buffer, 1024);
            encode(reinterpret_cast<uint8_t*>(buffer), data.gcount(), output);
          }
        }
      }

      template<class CharT, class Traits>
      static std::string encode(std::basic_istream<CharT,Traits>& data) noexcept {
        std::ostringstream out;
        encode(data, out);
        return out.str();
      }

      template<class CharT, class Traits, class Allocator>
      static void encode(const std::basic_string<CharT,Traits,Allocator>& data,
                         std::basic_ostream<CharT,Traits>& output) noexcept {
        encode(reinterpret_cast<const uint8_t*>(data.data()), data.length(), output);
      }

      template<class CharT, class Traits, class Allocator>
      static std::string encode(const std::basic_string<CharT,Traits,Allocator>& data)
        noexcept {
        std::ostringstream out;
        encode(data, out);
        return out.str();
      }

      template<class CharT, class Traits>
      static void encode(const uint8_t* data, uint64_t length,
                         std::basic_ostream<CharT,Traits>& output)
        noexcept {
        char buffer[5];
        buffer[4] = '\0';
        while(length > 0) {
          uint8_t read = encode(data, length, buffer);
          output << buffer;
          data += read;
          length -= read;
        }
      }

      static std::string encode(const uint8_t* data, uint64_t length) noexcept {
        std::ostringstream out;
        encode(data, length, out);
        return out.str();
      }

    private:
      static uint8_t encode(const uint8_t* data, uint64_t length, char buffer[5]) noexcept;
      // Encoding methods -


      // Decoding methods +
    public:
      template<class CharT, class Traits>
      static void decode(std::istream& data,
                         std::basic_ostream<CharT,Traits>& output)
        noexcept {
        if(data) {
          char buffer[1024];
          while(!data.eof()) {
            data.read(buffer, 1024);
            decode(buffer, data.gcount(), output);
          }
        }
      }

      static std::string decode(std::istream& data) noexcept {
        std::ostringstream out;
        decode(data, out);
        return out.str();
      }

      template<class CharT, class Traits>
      static void decode(const std::string& data,
                         std::basic_ostream<CharT,Traits>& output) noexcept {
        decode(data.data(), data.length(), output);
      }

      static std::string decode(const std::string& data)
        noexcept {
        std::ostringstream out;
        decode(data, out);
        return out.str();
      }

      template<class CharT, class Traits>
      static void decode(const char* data, uint64_t length,
                         std::basic_ostream<CharT,Traits>& output)
        noexcept {
        uint8_t buffer[4];
        buffer[3] = '\0';
        while(length > 0) {
          memset(buffer, '\0', 3);
          decode(data, length, buffer);
          output << buffer;
          data += 4;
          length -= 4;
        }
      }

      static std::string decode(const char* data, uint64_t length)
        noexcept {
        std::ostringstream out;
        decode(data, length, out);
        return out.str();
      }

    private:
      static void decode(const char* data, uint64_t length, uint8_t buffer[4]) noexcept;
      // Decoding methods -

    };

  }
}

#endif // _ANCH_CRYPTO_B2T_BASE64_H_