#include "camera.h"
Camera::Camera() {
  this->width = Window::width;
  this->height = Window::height;

  this->field_of_view = glm::radians(80.0f);

  this->projection_matrix = glm::perspective(
    this->field_of_view, 
    (float)this->width / (float)this->height, 
    0.1f, 
    1000.0f
  );

  Window::current_window->register_resize_callback((void(*)(void*, int, int))&Camera::update_projection_matrix, this);
}

void Camera::update_projection_matrix(int width, int height) {
  this->width = width;
  this->height = height;

  this->projection_matrix = glm::perspective(
    this->field_of_view, 
    (float)this->width / (float)this->height, 
    0.1f, 
    1000.0f
  );
}

glm::mat4 Camera::get_projection_matrix() {
  return this->projection_matrix;
}

glm::mat4 Camera::get_view_matrix() {
  glm::mat4 r1Matrix = glm::rotate(-this->rotation.x, glm::vec3(1, 0, 0));
  glm::mat4 r2Matrix = glm::rotate(-this->rotation.y, glm::vec3(0, 1, 0));
  glm::mat4 r3Matrix = glm::rotate(-this->rotation.z, glm::vec3(0, 0, 1));
  glm::mat4 tMatrix = glm::translate(glm::mat4(1.0f), -this->position);
  return r1Matrix * r2Matrix * r3Matrix * tMatrix;
}

glm::vec3 Camera::get_position() {
  return this->position;
}
void Camera::set_position(glm::vec3 position) {
  this->position = position;
}
void Camera::change_position_by(glm::vec3 position) {
  this->position += position;
}

glm::vec3 Camera::get_rotation() {
  return this->rotation;
}
void Camera::set_rotation(glm::vec3 rotation) {
  this->rotation = rotation;
}
void Camera::change_rotation_by(glm::vec3 rotation) {
  this->rotation += rotation;
}

void Camera::move_by(glm::vec3 position) {
  glm::vec3 forward(
    glm::cos(-this->rotation.x) * glm::sin(this->rotation.y),
    glm::sin(-this->rotation.x),
    glm::cos(-this->rotation.x) * glm::cos(this->rotation.y)
  );

  glm::vec3 right(
    glm::sin(this->rotation.y + 1.57f),
    0,
    glm::cos(this->rotation.y + 1.57f)
  );

  glm::vec3 up = -glm::cross(right, forward);

  this->position += right * position.x;
  this->position += up * position.y;
  this->position += forward * position.z;
}