/* is_check for the current king position */
bool Board::is_check(Color c)
{
    Color opponent = get_opponent_color(c);
    int king_pos = BitboardHelper::get_position(board_[c][KING]);

    return
        (is_a_valid_move(king_pos, KING, opponent, false, false)
         || is_a_valid_move(king_pos, QUEEN, opponent, false, false)
         || is_a_valid_move(king_pos, KNIGHTS, opponent, false, false)
         || is_a_valid_move(king_pos, ROOKS, opponent, false, false)
         || is_a_valid_move(king_pos, BISHOPS, opponent, false, false)
         || is_a_valid_move(king_pos, PAWNS, opponent, false, false)
         || is_a_valid_move(king_pos, PAWNS, opponent, false, true)
         || is_a_valid_move(king_pos, PAWNS, opponent, true, false));
}

/* is_check for a given king position (each possible move) */
bool Board::is_check(int king_pos, Color c)
{
    Color opponent = get_opponent_color(c);

    return
        (is_a_valid_move(king_pos, KING, opponent, false, false)
         || is_a_valid_move(king_pos, QUEEN, opponent, false, false)
         || is_a_valid_move(king_pos, KNIGHTS, opponent, false, false)
         || is_a_valid_move(king_pos, ROOKS, opponent, false, false)
         || is_a_valid_move(king_pos, BISHOPS, opponent, false, false)
         || is_a_valid_move(king_pos, PAWNS, opponent, false, false)
         || is_a_valid_move(king_pos, PAWNS, opponent, false, true)
         || is_a_valid_move(king_pos, PAWNS, opponent, true, false));
}

bool Board::is_checkmate(Color c)
{
    if (!is_check(c))
        return false;

    for (int m : BitboardHelper::get_positions(get_king_attacks(
                    BitboardHelper::get_position(board_[c][KING]), c)))
        if (!is_check(m, c))
            return false;

    return true;
}