BGN2/bgn2/inc/Scalar.hpp

#ifndef __SCALAR_HPP
#define __SCALAR_HPP

#include <ostream>
#include <stdlib.h>
#include <sstream>
#include <gmpxx.h>

#include "Bipoint.hpp"
#include "Quadripoint.hpp"

#include "scalar.h"

class Scalar
{
    public:
        Scalar();
        Scalar(const scalar_t& input);
        Scalar(mpz_class input);

        void set(const scalar_t& input);
        void set(mpz_class input);
        void set_random();

        Scalar operator-() const;
        Scalar operator+(const Scalar& b) const;
        Scalar operator-(const Scalar& b) const;
        Scalar operator*(const Scalar& b) const;
        Scalar operator/(const Scalar& b) const;
        Scalar& operator++();
        Scalar operator++(int);
        Scalar& operator--();
        Scalar operator--(int);

        curvepoint_fp_t operator*(const curvepoint_fp_t& b) const;
        twistpoint_fp2_t operator*(const twistpoint_fp2_t& b) const;
        fp12e_t operator*(const fp12e_t& b) const;
        Bipoint<curvepoint_fp_t> operator*(const Bipoint<curvepoint_fp_t>& b) const;
        Bipoint<twistpoint_fp2_t> operator*(const Bipoint<twistpoint_fp2_t>& b) const;
        Quadripoint operator*(const Quadripoint& b) const;

        bool operator==(const Scalar& b) const;
        bool operator!=(const Scalar& b) const;
        
        friend std::ostream& operator<<(std::ostream& os, const Scalar& output);
    
    private:
        class SecretScalar
        {
            SecretScalar();
            SecretScalar(const Scalar& input);
            SecretScalar(mpz_class input);

            // Problem: thanks to the magic of weird typedefs, scalar_t is actually an array, which complicates returning it
            // Solution: make the return value a reference
            // This feels bad, I know, but it will only be used in places where the variable remains in scope for the duration of usage
            const scalar_t& expose() const;

            private:
                void set(mpz_class input);
                scalar_t element;
        };
        SecretScalar to_scalar_t() const;

        static const mpz_class mpz_bn_n("8FB501E34AA387F9AA6FECB86184DC212E8D8E12F82B39241A2EF45B57AC7261", 16);

        mpz_class element;
};

#endif