#pragma once

#include "Common.hpp"

namespace Math::MVP {

template<typename T = Real>
Matrix<4, 4, T> model(Vector<3> position, Vector<3> size, Rotation angles) {
    auto transformation = Matrix<4, 4, T>::transformation(position);
    auto scale = Matrix<4, 4, T>::scale(size);
    auto rotation = Matrix<4, 4, T>::rotation(angles);

    return transformation * rotation * scale;
}

template<typename T = Real>
Matrix<4, 4, T> view(Vector<3> position, Rotation angles) {
    auto rotation = Matrix<4, 4, T>::rotation(angles);
    auto transformation = Matrix<4, 4, T>::transformation(-position);

    return rotation * transformation;
}

template<typename T = Real>
Matrix<4, 4, T> perspective_projection(Real aspect, Real fov, Real near, Real far) {
    auto fov_radians = radians(fov);

    Real x_scale = 1.0 / (tan(fov_radians / 2.0) * aspect);
    Real y_scale = 1.0 / tan(fov_radians / 2.0);

    Real frustum_length = far - near;
    Real z_near = -(far + near) / frustum_length;
    Real z_far = -(2 * far * near) / frustum_length;

    Matrix<4, 4, T> projection{
        x_scale, 0.0f,    0.0f,   0.0f,
        0.0f,    y_scale, 0.0f,   0.0f,
        0.0f,    0.0f,    z_near, z_far,
        0.0f,    0.0f,    -1.0f,   0.0f,
    };

    return projection;
}

template<typename T = Real>
Matrix<4, 4, T> orthographic_projection(Real width, Real height, Real near, Real far) {
    Real x_scale = 2.0f / width;
    Real y_scale = 2.0f / -height;

    Real frustum_length = far - near;
    Real z_near = -(far + near) / frustum_length;
    Real z_far = -2 / frustum_length;

    Matrix<4, 4, T> projection{
        x_scale, 0.0f,    0.0f,   -1.0f,
        0.0f,    y_scale, 0.0f,   1.0f,
        0.0f,    0.0f,    z_near, z_far,
        0.0f,    0.0f,    0.0f,   1.0f,
    };

    return projection;
}

}