#include <assert.h>
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>

#include "drm.h"
#include "egl.h"

/**
 * When Linux detects a GPU it loads modprobes the device driver
 * to provide two character-devices to control it. Udev (or whatever
 * hotplugging framework) will create them as:
 *    /dev/dri/card0
 *    /dev/dri/controlID64
 * We only need the first one. We simply hardcode its path though
 * libudev would be the way to do real hotplugging. 
 *
 * This helper opens the DRM device which is given as 'node'. The
 * new fd is stored in 'out' on success. On failure a negative err
 * code is returned.
 *
 * After openning the file, we check for the DRM_CAP_DUMB_BUFFER
 * capability. If the driver supports this capability, we can
 * create simple memory-mapped buffers without any driver-dependent
 * code, as want to avoid any vendor specifics.
 */

struct egl egl;
static const struct gbm *gbm;
static const struct drm *drm;

extern void run_gl_example();// XX move to header.

int main()
{
	const char * card = "/dev/dri/card0";

	drm = init_drm_runner(card);
	if (!drm) {
		fprintf(stderr, "failed to initialize DRM\n");
		exit(1);
	}

	gbm = init_gbm(drm->fd, drm->mode->hdisplay, drm->mode->vdisplay);
	if (!gbm) {
		printf("failed to initialize GBM\n");
		exit(1);
	}

	init_egl(&egl, gbm);

	/* ...... */
	/* draw here?? */
	setup_egl_draw_loop(&egl, run_gl_example);
	drm->run(gbm, &egl); // main render loop
	/* ...... */

	/* cleanups */
	deinit_egl(&egl);
	deinit_gbm(gbm);
	deinit_drm(drm);

	return 0;
}