// gcc example/c/gl_sdl2.c build/src/gl.c -Ibuild/include `sdl2-config --libs --cflags` -ldl
#include <stdlib.h>
#include <stdio.h>

#include <glad/gl.h>
#include <SDL.h>
#include <SDL_opengl.h>


const GLuint WIDTH = 800, HEIGHT = 600;

int main(void) {
    // code without checking for errors
    SDL_Init(SDL_INIT_VIDEO);

    SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 2);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);

    SDL_Window *window = SDL_CreateWindow(
        "[glad] GL with SDL",
        SDL_WINDOWPOS_CENTERED,
        SDL_WINDOWPOS_CENTERED,
        WIDTH, HEIGHT,
        SDL_WINDOW_OPENGL | SDL_WINDOW_SHOWN
    );

    SDL_GLContext context = SDL_GL_CreateContext(window);

    int version = gladLoadGL((GLADloadfunc) SDL_GL_GetProcAddress);
    printf("GL %d.%d\n", GLAD_VERSION_MAJOR(version), GLAD_VERSION_MINOR(version));

    int exit = 0;
    while(!exit) {
        SDL_Event event;
        while (SDL_PollEvent(&event)) {
            switch(event.type) {
                case SDL_QUIT:
                    exit = 1;
                    break;
                case SDL_KEYUP:
                    if (event.key.keysym.sym == SDLK_ESCAPE) {
                        exit = 1;
                    }
                    break;
                default:
                    break;
            }
        }

        glClearColor(0.7f, 0.9f, 0.1f, 1.0f);
        glClear(GL_COLOR_BUFFER_BIT);

        SDL_GL_SwapWindow(window);
        SDL_Delay(1);
    }

    SDL_GL_DeleteContext(context);
    SDL_DestroyWindow(window);
    SDL_Quit();

    return 0;
}