#include <stdbool.h>
#include <stdio.h>

#include "world.h"
#include "runner.h"

static bool world_test_0(const char ** scenario)
{
  *scenario = "Creating a world";

  struct world w = world();

  return
    w.object_count == 0 &&
    tuple_equal(w.light.intensity, tuple(0.0f, 0.0f, 0.0f, 0.0f));
}

static bool world_test_1(const char ** scenario)
{
  *scenario = "The default world";

  struct light light = point_light(point(-10.0f, 10.0f, -10.0f), color(1.0f, 1.0f, 1.0f));
  struct sphere s1 = sphere();
  s1.material.color = color(0.8f, 1.0f, 0.6f);
  s1.material.diffuse = 0.7f;
  s1.material.specular = 0.2f;
  struct sphere s2 = sphere();
  s2.transform = scaling(0.5f, 0.5f, 0.5f);
  struct world w = world_default();
  return
    tuple_equal(w.light.position, light.position) &&
    tuple_equal(w.light.intensity, light.intensity) &&
    w.object_count == 2 &&
    tuple_equal(w.objects[0].material.color, s1.material.color) &&
    float_equal(w.objects[0].material.diffuse, s1.material.diffuse) &&
    float_equal(w.objects[0].material.specular, s1.material.specular) &&
    mat4x4_equal(&w.objects[1].transform, &s2.transform);
}

static bool world_test_2(const char ** scenario)
{
  *scenario = "Intersect a world with a ray";

  struct world w = world_default();

  struct ray r = ray(point(0.0f, 0.0f, -5.0f), vector(0.0f, 0.0f, 1.0f));
  struct intersections xs;
  world_intersect(&w, r, &xs);

  return
    xs.count == 4 &&
    float_equal(xs.i[0].t, 4.0f) &&
    float_equal(xs.i[1].t, 4.5f) &&
    float_equal(xs.i[2].t, 5.5f) &&
    float_equal(xs.i[3].t, 6.0f);
}

static bool world_test_3(const char ** scenario)
{
  *scenario = "Shading an intersection";

  struct world w = world_default();
  struct ray r = ray(point(0.0f, 0.0f, -5.0f), vector(0.0f, 0.0f, 1.0f));
  struct sphere * shape = &w.objects[0];
  struct intersection i = intersection(4.0f, shape);
  struct computations comps = prepare_computations(i, r);
  struct tuple c = world_shade_hit(&w, &comps);

  return tuple_equal(c, color(0.38066, 0.47583, 0.2855));
}

static bool world_test_4(const char ** scenario)
{
  *scenario = "Shading an intersection from the inside";

  struct world w = world_default();
  w.light = point_light(point(0.0f, 0.25f, 0.0f), color(1.0f, 1.0f, 1.0f));
  struct ray r = ray(point(0.0f, 0.0f, 0.0f), vector(0.0f, 0.0f, 1.0f));
  struct sphere * shape = &w.objects[1];
  struct intersection i = intersection(0.5f, shape);
  struct computations comps = prepare_computations(i, r);
  struct tuple c = world_shade_hit(&w, &comps);

  return tuple_equal(c, color(0.90498, 0.90498, 0.90498));
}

static bool world_test_5(const char ** scenario)
{
  *scenario = "The color when a ray misses";

  struct world w = world_default();
  struct ray r = ray(point(0.0f, 0.0f, -5.0f), vector(0.0f, 1.0f, 0.0f));
  struct tuple c = world_color_at(&w, r);

  return tuple_equal(c, color(0.0f, 0.0f, 0.0f));
}

static bool world_test_6(const char ** scenario)
{
  *scenario = "The color when a ray hits";

  struct world w = world_default();
  struct ray r = ray(point(0.0f, 0.0f, -5.0f), vector(0.0f, 0.0f, 1.0f));
  struct tuple c = world_color_at(&w, r);

  return tuple_equal(c, color(0.38066f, 0.47583f, 0.2855f));
}

static bool world_test_7(const char ** scenario)
{
  *scenario = "The color with an intersection behind the ray";

  struct world w = world_default();
  struct sphere * outer = &w.objects[0];
  outer->material.ambient = 1.0f;
  struct sphere * inner = &w.objects[1];
  inner->material.ambient = 1.0f;
  struct ray r = ray(point(0.0f, 0.0f, 0.75f), vector(0.0f, 0.0f, -1.0f));
  struct tuple c = world_color_at(&w, r);

  return tuple_equal(c, inner->material.color);
}

static bool world_test_8(const char ** scenario)
{
  *scenario = "There is no shadow when nothing is collinear with point and light";

  struct world w = world_default();
  struct tuple p = point(0.0f, 10.0f, 0.0f);

  return world_is_shadowed(&w, p) == false;
}

static bool world_test_9(const char ** scenario)
{
  *scenario = "The shadow when an object is between the point and the light";

  struct world w = world_default();
  struct tuple p = point(10.0f, -10.0f, 10.0f);

  return world_is_shadowed(&w, p) == true;
}

static bool world_test_10(const char ** scenario)
{
  *scenario = "There is no shadow when an object is behind the light";

  struct world w = world_default();
  struct tuple p = point(-20.0f, 20.0f, -20.0f);

  return world_is_shadowed(&w, p) == false;
}

static bool world_test_11(const char ** scenario)
{
  *scenario = "There is not shadow when an object is behind the point";

  struct world w = world_default();
  struct tuple p = point(-2.0f, 2.0f, -2.0f);

  return world_is_shadowed(&w, p) == false;
}

static bool world_test_12(const char ** scenario)
{
  *scenario = "shade_hit() is given an intersection in shadow";

  struct world w = world();
  w.light = point_light(point(0.0f, 0.0f, -10.0f), color(1.0f, 1.0f, 1.0f));
  struct sphere s1 = sphere();
  w.objects[0] = s1;
  struct sphere s2 = sphere();
  s2.transform = translation(0.0f, 0.0f, 10.0f);
  w.objects[1] = s2;
  w.object_count = 2;
  struct ray r = ray(point(0.0f, 0.0f, 5.0f), vector(0.0f, 0.0f, 1.0f));
  struct intersection i = intersection(4.0f, &s2);
  struct computations comps = prepare_computations(i, r);
  struct tuple c = world_shade_hit(&w, &comps);

  return tuple_equal(c, color(0.1f, 0.1f, 0.1f));
}

test_t world_tests[] = {
  world_test_0,
  world_test_1,
  world_test_2,
  world_test_3,
  world_test_4,
  world_test_5,
  world_test_6,
  world_test_7,
  world_test_8,
  world_test_9,
  world_test_10,
  world_test_11,
  world_test_12,
};

RUNNER(world_tests)