/*
 * Codec.hpp
 *
 *  Created on: 21 пїЅпїЅпїЅ. 2019 пїЅ.
 *      Author: krugliy
 */

#ifndef SOURCE_COMMON_CODEC_HPP_
#define SOURCE_COMMON_CODEC_HPP_


#include <type_traits>

#if __cplusplus > 199711L
namespace std {
    namespace tr1 {

using std::enable_if;
using std::is_unsigned;

    }
}
#endif

namespace codec {

struct BinDecoder {
    template<typename T,
            class = typename std::tr1::enable_if<std::tr1::is_unsigned<T>::value>::type
    >
    T operator()( T bin, unsigned short most_signed_bit_pos  ) {
        return bin & ((1ull << most_signed_bit_pos) - 1);
    }
};

struct InverseBinDecoder {
    template<typename T,
            class = typename std::tr1::enable_if<std::tr1::is_unsigned<T>::value>::type
    >
    T operator()( T bin, unsigned short most_signed_bit_pos  ) {
        return ~bin & ((1ull << most_signed_bit_pos) - 1);
    }
};

//!пїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅ пїЅ пїЅпїЅпїЅ пїЅпїЅпїЅпїЅ.
struct GrayCodeCoder {

    template<typename T,
            class = typename std::tr1::enable_if<std::tr1::is_unsigned<T>::value>::type
    >
    T operator()( T bin ) {
        return bin ^ (bin >> 1);
    }

};

//!пїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅ пїЅпїЅ пїЅпїЅпїЅпїЅ пїЅпїЅпїЅпїЅ.
struct GrayCodeDecoder {

    template<typename T,
            class = typename std::tr1::enable_if<std::tr1::is_unsigned<T>::value>::type
    >
    T operator()( T gray_code, unsigned short most_signed_bit_pos ) {

        T raw_code = 0;
        for( ; gray_code; gray_code >>= 1 )
            raw_code ^= gray_code;

        return raw_code;
        //return (~raw_code) & ((1ull << most_signed_bit_pos) - 1); //пїЅпїЅпїЅпїЅ пїЅпїЅпїЅпїЅпїЅ

    }

};

//!пїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅ пїЅпїЅ пїЅпїЅпїЅпїЅ пїЅпїЅпїЅпїЅ пїЅ пїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅ пїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅ пїЅпїЅпїЅпїЅпїЅ.
struct InverseGrayCodeDecoder : private GrayCodeDecoder {

    //!most_signed_bit_pos - пїЅпїЅпїЅпїЅпїЅпїЅпїЅ пїЅпїЅпїЅпїЅпїЅпїЅпїЅпїЅ пїЅпїЅпїЅпїЅ пїЅ пїЅпїЅпїЅпїЅ. пїЅпїЅпїЅпїЅ пїЅпїЅпїЅ n-пїЅпїЅпїЅпїЅпїЅпїЅ, most_signed_bit_pos = n - 1
    template<typename T,
            class = typename std::tr1::enable_if<std::tr1::is_unsigned<T>::value>::type
    >
    T operator()( T gray_code, unsigned short most_signed_bit_pos ) {
        return GrayCodeDecoder::operator()( gray_code ^ (1 << most_signed_bit_pos), most_signed_bit_pos );
    }

};

}

#endif /* SOURCE_COMMON_CODEC_HPP_ */