#include <SDL.h>
#include <SDL_image.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdint.h>
#include <errno.h>
#include <string.h>
#include "kiss.h"

char *title = "SDL 08 - Geometry Rendering";
SDL_Window *window;
SDL_Renderer *renderer;

int
init_sdl(void)
{
   int status = -1;
   int x = SDL_WINDOWPOS_UNDEFINED;
   int y = SDL_WINDOWPOS_UNDEFINED;
   int width = 800;
   int height = 600;
   int flags = 0;       // SDL_WINDOW_FULLSCREEN_DESKTOP

   SDL_INIT(SDL_INIT_VIDEO);
   IMG_INIT(IMG_INIT_PNG);
   window = SDL_CREATEWINDOW(title, x, y, width, height, flags);
   renderer = SDL_CREATERENDERER(window, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
   status = 0;
error:
   return status;
}

#define INIT_SDL(...) SDL_ZERO(init_sdl, __VA_ARGS__)

void
close_sdl(void)
{
   SDL_DestroyRenderer(renderer);
   SDL_DestroyWindow(window);
   IMG_Quit();
   SDL_Quit();
}

int a = 0;

int
draw(void)
{
   int status = -1;
   int w, h;
   int i;
   SDL_GetWindowSize(window, &w, &h);
   SDL_SetRenderDrawColor(renderer, 0x00, 0x00, 0x00, 0xFF);
   SDL_RENDERCLEAR(renderer);
   SDL_SetRenderDrawColor(renderer, 0xFF, 0x00, 0x00, 0xFF);
   SDL_RENDERFILLRECT(renderer, &(SDL_Rect){w / 4, h / 4, w / 2, h / 2});
   SDL_SetRenderDrawColor(renderer, 0x00, 0xFF, 0x00, 0xFF);
   SDL_RENDERDRAWRECT(renderer, &(SDL_Rect){w / 6, h / 6, w * 2 / 3, h * 2 / 3});
   SDL_SetRenderDrawColor(renderer, 0x00, 0x00, 0xFF, 0xFF);
   SDL_RENDERDRAWLINE(renderer, 0, a % h, w, h - a % h);
   SDL_SetRenderDrawColor(renderer, 0xFF, 0xFF, 0x00, 0xFF);
   for (i = 0; i < h; i += 4)
     {
        SDL_RENDERDRAWPOINT(renderer, a % w, i);
     }
   SDL_RenderPresent(renderer);
   status = 0;
error:
   return status;
}

#define DRAW(...) SDL_ZERO(draw, __VA_ARGS__)

int
main(void)
{
   int exit_status = EXIT_FAILURE;
   bool quit = 0;
   SDL_Event e;

   INIT_SDL();

   while (!quit)
     {
        if (SDL_PollEvent(&e))
          if (e.type == SDL_QUIT)
            quit = 1;
        DRAW();
        a += 1;
     }

   exit_status = EXIT_SUCCESS;
error:
   close_sdl();
   exit(exit_status);
}