#ifndef GEOMETRY_H

#include "color.h"
#include "point.h"
#include <cstdint>
#include <vector>


// STRUCTURES
struct Material
{
    ColorF32 kAmbient;
    ColorF32 kDiffuse;
};

struct Face
{
    unsigned int vertIndex[3];
    ColorU32 color;
};

struct Mesh
{
    inline Mesh(void)
    {
        position.x = 0.0f;
        position.y = 0.0f;
        position.z = 0.0f;

        rotation[0] = 0.0f;
        rotation[1] = 0.0f;
        rotation[2] = 0.0f;

        scale = 1.0f;
    }

    inline void CullBackfaces(Point camPosition)
    {
        culledFaces.clear();

        for (size_t f = 0; f < faces.size(); ++f)
        {
            unsigned int v0 = faces[f].vertIndex[0];
            unsigned int v1 = faces[f].vertIndex[1];
            unsigned int v2 = faces[f].vertIndex[2];

            Vector v01 = vertsTransformed[v1] - vertsTransformed[v0];
            Vector v02 = vertsTransformed[v2] - vertsTransformed[v0];

            Vector normal = Vector::Cross(v01, v02);

            // Invert for Blender-compatibility
            normal = -normal;

            // Eye vector to viewport
            Vector view = camPosition - vertsTransformed[v0];

            float dot = Vector::Dot(normal, view);

            if (dot < EPSILON_E3)
            {
                culledFaces.push_back(faces[f]);
            }
        }
    }

    Point position;
    float rotation[3];
    float scale;
    std::vector<Point> verts;
    std::vector<Point> vertsTransformed;
    std::vector<Face> faces;
    std::vector<Face> culledFaces;
    Material material;
};


// PUBLIC FUNCTIONS
void FillTriangle(
        uint32_t *buffer, int width,
        float *zbuffer, uint32_t color,
        float x0, float y0, float z0,
        float x1, float y1, float z1,
        float x2, float y2, float z2);


#define GEOMETRY_H
#endif