/* GPU example: the application owns context binding, drawing and swap pacing. */
#include <yasl/yasl.h>
#include <yasl/gl.h>
#include <stdio.h>
#include <math.h>
#include <string.h>

typedef void (*clear_color_fn)(float, float, float, float);
typedef void (*clear_fn)(unsigned);
typedef void (*viewport_fn)(int, int, int, int);

int main(int argc, char **argv)
{
    bool smoke = argc == 2 && !strcmp(argv[1], "--smoke-test");
    yasl_surface *s = yasl_gl_surface_create("YASL OpenGL", 800, 600, 0, NULL, NULL);
    if (!s || !yasl_gl_make_current(s)) {
        const char *error;
        yasl_get_error(&error);
        fprintf(stderr, "%s\n", error);
        yasl_shutdown();
        return 1;
    }
    clear_color_fn clear_color = (clear_color_fn)yasl_gl_get_proc_address("glClearColor");
    clear_fn clear = (clear_fn)yasl_gl_get_proc_address("glClear");
    viewport_fn viewport = (viewport_fn)yasl_gl_get_proc_address("glViewport");
    if (!clear_color || !clear || !viewport) {
        yasl_shutdown();
        return 1;
    }
    yasl_gl_swap_interval(s, 1);
    int result = 0, frames = 0;
    for (bool running = true; running;) {
        yasl_event e;
        int n;
        while ((n = yasl_wait_event(&e, 0)) > 0) {
            if (e.type == YASL_EVENT_CLOSE || e.type == YASL_EVENT_QUIT ||
                (e.type == YASL_EVENT_KEY && e.key.key == YASL_KEY_ESCAPE)) running = false;
            if (e.type == YASL_EVENT_DISPLAY_LOST) { result = 1; running = false; }
        }
        if (n < 0) { result = 1; break; }
        int w, h;
        yasl_surface_get_framebuffer_size(s, &w, &h);
        viewport(0, 0, w, h);
        double t = yasl_time_ns() / 1e9;
        clear_color((float)(0.3 + 0.2 * sin(t)), 0.2f, 0.4f, 1);
        clear(0x00004000u);
        if (!yasl_gl_swap_buffers(s)) { result = 1; break; }
        if (smoke && ++frames == 3) break;
    }
    yasl_gl_make_current(NULL);
    yasl_shutdown();
    return result;
}