#ifndef HITTABLE_H
#define HITTABLE_H

#include <memory>

#include "ray.h"
#include "material.h"
#include "aabb.h"

class Material;

struct hit_record {
  Point3 p;
  Vec3 normal;
  std::shared_ptr<Material> mat_ptr;
  double t;
  double u;
  double v;
  bool front_face;

  inline void set_face_normal(const Ray& r, const Vec3& outward_normal) {
    front_face = dot(r.direction(), outward_normal) < 0;
    normal = front_face ? outward_normal : -outward_normal;
  }
};

class Hittable {
public:
  virtual bool hit(const Ray &r, double tmin, double tmax, hit_record &rec) const = 0;
  virtual bool bounding_box(double t0, double t1, Aabb& output_box) const = 0;
};

class Flip_face : public Hittable {
  public:
    Flip_face(std::shared_ptr<Hittable> p) : ptr(p) {}

  virtual bool hit(const Ray &r, double tmin, double tmax, hit_record &rec) const;

  virtual bool bounding_box(double t0, double t1, Aabb& output_box) const {
      return ptr->bounding_box(t0, t1, output_box);
  }

  private:
    std::shared_ptr<Hittable> ptr;
};

class Translate : public Hittable {
  public:
    Translate(std::shared_ptr<Hittable> p, const Vec3& displacement) : ptr(p), offset(displacement) {}

    virtual bool hit(const Ray &r, double tmin, double tmax, hit_record &rec) const;
    virtual bool bounding_box(double t0, double t1, Aabb& output_box) const;

  private:
    std::shared_ptr<Hittable> ptr;
    Vec3 offset;
};

class Rotate_y : public Hittable {
  public:
    Rotate_y(std::shared_ptr<Hittable> p, double angle);

    virtual bool hit(const Ray& r, double tmin, double tmax, hit_record& rec) const;
    virtual bool bounding_box(double t0, double t1, Aabb& output_box) const {
        output_box = bbox;
        return hasbox;
    }

  private:
    std::shared_ptr<Hittable> ptr;
    double sin_theta;
    double cos_theta;
    bool hasbox;
    Aabb bbox;
};

#endif // HITTABLE_H