#ifndef MATERIAL_H
#define MATERIAL_H

#include "hittable.h"
#include "vec3.h"
#include "texture.h"

struct hit_record;

class Material {
public:
  virtual bool scatter(const Ray& r_in, const hit_record& rec, Color& attenuation, Ray& scattered) const = 0;
  virtual Color emitted(double u, double v, const Point3& p) const { return Color(0, 0, 0); }
};

class Lambertian : public Material {
public:
  Lambertian(std::shared_ptr<Texture> a) : albedo(a) {}

  virtual bool scatter(const Ray& r_in, const hit_record& rec, Color& attenuation, Ray& scattered) const;

private:
  std::shared_ptr<Texture> albedo;
};

class Metal : public Material {
public:
  Metal(const Color& a, double f) : albedo(a), fuzz(f < 1 ? f : 1) {}

  virtual bool scatter(const Ray& r_in, const hit_record& rec, Color& attenuation, Ray& scattered) const;
private:
  Color albedo;
  double fuzz;
};

double schlick(double cosine, double ref_idx);

class Dielectric : public Material {
public:
  Dielectric(double ri) : ref_idx(ri) {}
  virtual bool scatter(const Ray& r_in, const hit_record& rec, Color& attenuation, Ray& scattered) const;
private:
  double ref_idx;
};

class Diffuse_light : public Material {
  public:
    Diffuse_light(std::shared_ptr<Texture> a) : emit(a) {}

    virtual bool scatter(const Ray& r_in, const hit_record& rec, Color& attenuation, Ray& scattered) const {
        return false;
    }

    virtual Color emitted(double u, double v, const Point3& p) const { return emit->value(u, v, p); }

  private:
    std::shared_ptr<Texture> emit;
};

#endif // MATERIAL_H