/*
 * Copyright 2022 Frederico de Oliveira Linhares
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "camera.hpp"

#include "vk/camera.hpp"

void
cg_free_camera(mrb_state *mrb, void* obj)
{
  auto ptr = static_cast<std::shared_ptr<VK::Camera>*>(obj);

  ptr->~shared_ptr();
  mrb_free(mrb, ptr);
}

const struct mrb_data_type cg_camera_type = {"CG_Camera", cg_free_camera};

static mrb_value
cg_cCamera_initialize(mrb_state *mrb, mrb_value self)
{
  mrb_float position_x, position_y, position_z,
    rotation_x, rotation_y, rotation_z;
  std::shared_ptr<VK::Camera> *ptr;

  mrb_get_args(
    mrb, "ffffff",
    &position_x, &position_y, &position_z,
    &rotation_x, &rotation_y, &rotation_z);
  ptr = (std::shared_ptr<VK::Camera>*)DATA_PTR(self);
  if(ptr) mrb_free(mrb, ptr);
  ptr = (std::shared_ptr<VK::Camera>*)mrb_malloc(
    mrb, sizeof(std::shared_ptr<VK::Camera>));
  
  new(ptr)std::shared_ptr<VK::Camera>(std::make_shared<VK::Camera>());
  (*ptr)->position = glm::vec3(position_x, position_y, position_z);
  (*ptr)->rotation = glm::vec3(rotation_x, rotation_y, rotation_z);

  mrb_data_init(self, ptr, &cg_camera_type);
  return self;
}

static mrb_value
cg_cCamera_use(mrb_state *mrb, mrb_value self)
{
  std::shared_ptr<VK::Camera> *ptr;

  ptr = (std::shared_ptr<VK::Camera>*)DATA_PTR(self);
  cg_core.vk_graphics_pipeline->camera = (*ptr);

  return self;
}

static mrb_value
cg_cCamera_rotate(mrb_state *mrb, mrb_value self)
{
  mrb_float x, y, z;
  std::shared_ptr<VK::Camera> *ptr;

  mrb_get_args(mrb, "fff", &x, &y, &z);
  ptr = (std::shared_ptr<VK::Camera>*)DATA_PTR(self);

  (*ptr)->rotation.x += x;
  (*ptr)->rotation.y += y;
  (*ptr)->rotation.z += z;

  return self;
}

static mrb_value
cg_cCamera_translate(mrb_state *mrb, mrb_value self)
{
  mrb_float x, y, z;
  std::shared_ptr<VK::Camera> *ptr;

  mrb_get_args(mrb, "fff", &x, &y, &z);
  ptr = (std::shared_ptr<VK::Camera>*)DATA_PTR(self);

  (*ptr)->position.x += x;
  (*ptr)->position.y += y;
  (*ptr)->position.z += z;

  return self;
}

static mrb_value
cg_cCamera_translate_by_rotation(mrb_state *mrb, mrb_value self)
{
  mrb_float x, y, z;
  std::shared_ptr<VK::Camera> *ptr;

  mrb_get_args(mrb, "fff", &x, &y, &z);
  ptr = (std::shared_ptr<VK::Camera>*)DATA_PTR(self);

  glm::mat4 matrix{1.0f};
  matrix = glm::rotate(
    matrix, (*ptr)->rotation.x, glm::vec3{1.0f, 0.0f, 0.0f});
  matrix = glm::rotate(
    matrix, (*ptr)->rotation.y, glm::vec3{0.0f, 1.0f, 0.0f});
  matrix = glm::rotate(
    matrix, (*ptr)->rotation.z, glm::vec3{0.0f, 0.0f, 1.0f});

  glm::vec4 rotated_vector{matrix * glm::vec4{x, y, z, 1.0}};

  (*ptr)->position.x += rotated_vector.x;
  (*ptr)->position.y += rotated_vector.y;
  (*ptr)->position.z += rotated_vector.z;

  return self;
}

void
cg_camera_init(mrb_state *mrb)
{
  struct RClass *cg_m, *cg_cCamera;

  cg_m = mrb_module_get(mrb, "CandyGear");
  cg_cCamera = mrb_define_class_under(mrb, cg_m, "Camera", mrb->object_class);
  MRB_SET_INSTANCE_TT(cg_cCamera, MRB_TT_DATA);
  mrb_define_method(
    mrb, cg_cCamera, "initialize", cg_cCamera_initialize, MRB_ARGS_REQ(6));
  mrb_define_method(mrb, cg_cCamera, "use", cg_cCamera_use, MRB_ARGS_NONE());
  mrb_define_method(
    mrb, cg_cCamera, "rotate", cg_cCamera_rotate, MRB_ARGS_REQ(3));
  mrb_define_method(
    mrb, cg_cCamera, "translate", cg_cCamera_translate, MRB_ARGS_REQ(3));
  mrb_define_method(
    mrb, cg_cCamera, "translate_by_rotation",
    cg_cCamera_translate_by_rotation, MRB_ARGS_REQ(3));
}