castling.hpp

#pragma once
 
#include <cstdint>
 
struct Castling {
    enum : std::uint8_t {
        W_KING_SIDE  = 0b0001,
        W_QUEEN_SIDE = 0b0010,
        B_KING_SIDE  = 0b0100,
        B_QUEEN_SIDE = 0b1000,
 
        KING_SIDE  = W_KING_SIDE | B_KING_SIDE,    // 0b0101
        QUEEN_SIDE = W_QUEEN_SIDE | B_QUEEN_SIDE,  // 0b1010
        W_SIDE     = W_KING_SIDE | W_QUEEN_SIDE,   // 0b0011
        B_SIDE     = B_KING_SIDE | B_QUEEN_SIDE,   // 0b1100
        ANY        = W_SIDE | B_SIDE,              // 0b1111
 
        NONE = 0b0000,
 
        MASK = 0b1111,
        SIZE = 4,
        NB   = 4
    };
 
    constexpr Castling(uint8_t value) : m_value(value) {}
 
    [[nodiscard]] static constexpr uint8_t none() { return NONE; }
 
    [[nodiscard]] static constexpr uint8_t number() { return NB; }
    [[nodiscard]] static constexpr uint8_t mask() { return MASK; }
    [[nodiscard]] static constexpr uint8_t size() { return SIZE; }
 
    constexpr operator uint8_t() const { return m_value; }
 
   private:
    uint8_t m_value;
};