/**
 * Copyright (c) 2025 Dominic Masters
 * 
 * This software is released under the MIT License.
 * https://opensource.org/licenses/MIT
 */

#include "camera.h"
#include "display/display.h"
#include "assert/assert.h"
#include "scene/node.h"
#include "display/framebuffer/framebuffer.h"

camera_t CAMERA_DATA[ECS_ENTITY_COUNT_MAX] = { 0 };
ecscomponent_t CAMERA_COMPONENT = ecsComponentInit(
  CAMERA_DATA,
  ((ecscomponentcallbacks_t){
    .init = NULL,
    .entityAdd = cameraEntityAdded
  })
);

ecsid_t CAMERA_MAIN = -1;

void cameraEntityAdded(const ecsid_t id) {
  if(CAMERA_MAIN == -1) CAMERA_MAIN = id;

  camera_t *cam = cameraGet(id);
  cam->type = CAMERA_TYPE_PERSPECTIVE;
  cam->perspective.fov = glm_rad(90.0f);
  cam->nearClip = 0.1f;
  cam->farClip = 1000.0f;
  cam->clearColor = COLOR_CORNFLOWER_BLUE;
}

void cameraPush(const ecsid_t id) {
  assertTrue(cameraHas(id), "Not a camera component");

  camera_t *cam = cameraGet(id);

  mat4 projection, view;
  nodeMatrixGet(id, view);

  switch(cam->type) {
    case CAMERA_TYPE_ORTHOGRAPHIC:
      glm_ortho(
        cam->orthographic.left,
        cam->orthographic.right,
        cam->orthographic.bottom,
        cam->orthographic.top,
        cam->nearClip,
        cam->farClip,
        projection
      );
      break;

    case CAMERA_TYPE_PERSPECTIVE:
      glm_perspective(
        cam->perspective.fov,
        (
          (float_t)frameBufferGetWidth(FRAMEBUFFER_BOUND) /
          (float_t)frameBufferGetHeight(FRAMEBUFFER_BOUND)
        ),
        cam->nearClip,
        cam->farClip,
        projection
      );
  }

  #if DUSK_DISPLAY_SDL2
    mat4 pv;
    glm_mat4_mul(projection, view, pv);

    glPushMatrix();
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    glLoadMatrixf((const GLfloat*)pv);

    glClearColor(
      cam->clearColor.r / 255.0f,
      cam->clearColor.g / 255.0f,
      cam->clearColor.b / 255.0f,
      cam->clearColor.a / 255.0f
    );
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
  #endif
}

void cameraPop(void) {
  #if DUSK_DISPLAY_SDL2
    glPopMatrix();
  #endif
}