#pragma once

#include <array>

namespace fesa::elements {

using Vector12 = std::array<double, 12>;
using Matrix12 = std::array<double, 144>;
using Vector3 = std::array<double, 3>;

struct EulerBeam3DSection {
    double young_modulus;
    double shear_modulus;
    double area;
    double torsion_constant;
    double second_moment_y;
    double second_moment_z;
};

struct EulerBeam3DGeometry {
    Vector3 node1;
    Vector3 node2;
    Vector3 orientation;
};

Matrix12 euler_beam_3d_local_stiffness(double length, const EulerBeam3DSection& section);

Vector12 euler_beam_3d_local_end_forces(double length,
                                        const EulerBeam3DSection& section,
                                        const Vector12& local_displacements);

Matrix12 euler_beam_3d_global_stiffness(const EulerBeam3DGeometry& geometry,
                                        const EulerBeam3DSection& section);

Vector12 euler_beam_3d_global_end_forces(const EulerBeam3DGeometry& geometry,
                                         const EulerBeam3DSection& section,
                                         const Vector12& global_displacements);

} // namespace fesa::elements