/* standard lib imports */
#include <stdio.h>
#include <stdlib.h>

/* Xorg imports */
#include <X11/Xlib.h>
#include <X11/extensions/Xrandr.h>

/* This doesn't really do anything but allows the same output as the DisplayModeLister */
#define BIT_DEPTH_MULTI -1

/* 
 * xrandr-lsmodes -- binary to prove that the XRandr calls Java makes to list available display
 * modes are working ok.
 *
 * Screen mode listing code located in Java 7 / Icedtea 
 * http://icedtea.classpath.org/hg/openjdk/file/ce9dde984c21/j2se/src/solaris/native/sun/awt/awt_GraphicsEnv.c
 * function: Java_sun_awt_X11GraphicsDevice_enumDisplayModes(...)
 */

int main(/* int argc, char *argv[] */)
{
	Display *display;
	int screen_num;
	XRRScreenConfiguration *config;
	XRRScreenSize *sizes;
	int nsizes, i;
	
	char *display_name = getenv("DISPLAY"); /* address of X display */
	
	display = XOpenDisplay(display_name);
	if (NULL == display) {
		fprintf(stderr, "Cannot connection to X server %s\n", display_name);
		exit(-1);
	}
	screen_num = DefaultScreen(display);
	
	config = XRRGetScreenInfo(display, RootWindow(display, screen_num));
	if (NULL == config) {
		fprintf(stderr, "Could not retrieve screen configuration\n");
		exit(-1);
	}
	
	sizes = XRRConfigSizes(config, &nsizes);
	if (NULL == sizes) {
		fprintf(stderr, "Could not retrieve list of sizes\n");
		exit(-1);
	}
	
	for (i = 0; i < nsizes; ++i) {
		int nrates, j;
		XRRScreenSize size = sizes[i];
		short *rates = XRRConfigRates(config, i, &nrates);
		
		for (j = 0; j < nrates; ++j) {
			printf("%3d: %4d x%4d @ %dHz %dbit\n", 
					i+1, size.width, size.height, 
					rates[j], BIT_DEPTH_MULTI);
		}
	}

	XRRFreeScreenConfigInfo(config);
	XCloseDisplay(display);
	
	return 0;
}