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

#include "display/display.h"
#include "engine/engine.h"
#include "console/console.h"
#include "display/framebuffer.h"
#include "scene/scenemanager.h"
#include "display/spritebatch.h"
#include "display/mesh/quad.h"
#include "display/screen.h"
#include "ui/ui.h"

display_t DISPLAY;

errorret_t displayInit(void) {
  #if DISPLAY_SDL2
    uint32_t flags = SDL_INIT_VIDEO;
    #if INPUT_GAMEPAD == 1
      flags |= SDL_INIT_GAMECONTROLLER | SDL_INIT_JOYSTICK;
    #endif
    if(SDL_Init(flags) != 0) {
      errorThrow("SDL Failed to Initialize: %s", SDL_GetError());
    }

    // Set OpenGL attributes (Needs to be done now or later?)
    SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);

    // Create window with OpenGL flag.
    DISPLAY.window = SDL_CreateWindow(
      "Dusk",
      SDL_WINDOWPOS_UNDEFINED,
      SDL_WINDOWPOS_UNDEFINED,
      DISPLAY_WINDOW_WIDTH_DEFAULT,
      DISPLAY_WINDOW_HEIGHT_DEFAULT,
      SDL_WINDOW_SHOWN | SDL_WINDOW_RESIZABLE | SDL_WINDOW_ALLOW_HIGHDPI |
      SDL_WINDOW_OPENGL
    );
    if(!DISPLAY.window) {
      errorThrow("SDL_CreateWindow failed: %s", SDL_GetError());
    }

    // Create OpenGL context
    DISPLAY.glContext = SDL_GL_CreateContext(DISPLAY.window);
    if(!DISPLAY.glContext) {
      errorThrow("SDL_GL_CreateContext failed: %s", SDL_GetError());
    }

    SDL_GL_SetSwapInterval(1);
    glDisable(GL_DEPTH_TEST);
    glDisable(GL_CULL_FACE);
    glDisable(GL_LIGHTING);// PSP defaults this on?
    glShadeModel(GL_SMOOTH); // Fixes color on PSP?
    glEnable(GL_BLEND);
    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
    glPixelStorei(GL_PACK_ALIGNMENT, 1);
    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

    glEnableClientState(GL_COLOR_ARRAY);// To confirm: every frame on PSP?
    glEnableClientState(GL_TEXTURE_COORD_ARRAY);
    glEnableClientState(GL_VERTEX_ARRAY);
  #endif

  quadInit();
  frameBufferInitBackbuffer();
  spriteBatchInit();
  screenInit();

  errorOk();
}

errorret_t displayUpdate(void) {
  #if DISPLAY_SDL2
    SDL_Event event;
    while(SDL_PollEvent(&event)) {
      switch(event.type) {
        case SDL_QUIT: {
          ENGINE.running = false;
          break;
        }

        case SDL_WINDOWEVENT: {
          switch(event.window.event) {
            case SDL_WINDOWEVENT_CLOSE: {
              ENGINE.running = false;
              break;
            }
            
            default: {
              break;
            }
          }
        }

        default: {
          break;
        }
      }
    }

    SDL_GL_MakeCurrent(DISPLAY.window, DISPLAY.glContext);
  #endif

  // Reset state
  spriteBatchClear();
  frameBufferBind(NULL);
  
  // Bind screen and render scene
  screenBind();
  frameBufferClear(
    FRAMEBUFFER_CLEAR_COLOR | FRAMEBUFFER_CLEAR_DEPTH,
    COLOR_CORNFLOWER_BLUE
  );
  sceneManagerRender();
  uiRender();

  // Finish up
  spriteBatchFlush();
  screenUnbind();
  screenRender();

  #if DISPLAY_SDL2
    SDL_GL_SwapWindow(DISPLAY.window);
  #endif

  GLenum err;
  while((err = glGetError()) != GL_NO_ERROR) {
    consolePrint("GL Error: %d\n", err);
  }

  // For now, we just return an OK error.
  errorOk();
}

errorret_t displayDispose(void) {
  spriteBatchDispose();
  screenDispose();

  #if DISPLAY_SDL2
    if(DISPLAY.glContext) {
      SDL_GL_DeleteContext(DISPLAY.glContext);
      DISPLAY.glContext = NULL;
    }
    if(DISPLAY.window) {
      SDL_DestroyWindow(DISPLAY.window);
      DISPLAY.window = NULL;
    }
    SDL_Quit();
  #endif

  // For now, we just return an OK error.
  errorOk();
}