#include <u.h>
#include <libc.h>
#include <draw.h>
#include <event.h>
int x = 15, y = 10, c = 4, score, total;
ulong rgb[] = {DRed, DGreen, DBlue, DYellow, DCyan, DMagenta, 0x777777FF, DWhite};
Image **hue;
char *a;
void
eresized(int i)
{
	Point o;
	if(i && getwindow(display, Refnone) < 0)
		sysfatal("can't reattach to window");
	if((!i || Dx(screen->r) != x * 48 || Dy(screen->r) != y * 48)
	&& (i = open("/dev/wctl", OWRITE)) >= 0){
		fprint(i, "resize -dx %d -dy %d",
			x * 48 + 2 * Borderwidth,
			y * 48 + 2 * Borderwidth);
		close(i);
	}
	draw(screen, screen->r, display->black, nil, ZP);
	o = Pt(screen->r.min.x + 24, screen->r.max.y - 24);
	for(i = 0; i < x * y;){
		if(a[i] >= 0) fillellipse(screen, o, 20, 20, hue[a[i]], ZP);
		if(++i % y) o.y -= 48;
		else o = Pt(o.x + 48, screen->r.max.y - 24);
	}
}
void
flood(int i, int t){
	a[i] = -2;
	if((i + 1) % y && a[i + 1] == t) flood(i + 1, t);
	if(i + y < x * y && a[i + y] == t) flood(i + y, t);
	if(i % y && a[i - 1] == t) flood(i - 1, t);
	if(i >= y && a[i - y] == t) flood(i - y, t);
}
void
usage(void){
	sysfatal("usage: %s [-c colours] [-x width] [-y height]", argv0);
}
void
main(int argc, char **argv){
	Mouse m;
	int i, j;
	ARGBEGIN{
	default:
		usage();
	case 'c':
		c = atoi(EARGF(usage()));
		if(c < 2) sysfatal("%d colours not enough!", x);
		break;
	case 'x':
		x = atoi(EARGF(usage()));
		if(x < 2) sysfatal("width %d too small!", x);
		break;
	case 'y':
		y = atoi(EARGF(usage()));
		if(y < 2) sysfatal("height %d too small!", y);
		break;
	}ARGEND
	if((hue = calloc(c, sizeof(Image*))) == nil) sysfatal("calloc: %r");
	if((a = malloc(x * y)) == nil) sysfatal("malloc: %r");
	srand(truerand());
	for(i = 0; i < x * y; i++) a[i] = nrand(c);
	if(initdraw(nil, nil, argv0) < 0) sysfatal("initdraw: %r");
	for(i = 0; i < c; i++)
		if((hue[i] = allocimage(display, Rect(0,0,1,1), screen->chan, 1, rgb[i])) == nil)
			sysfatal("allocimage: %r");
	einit(Emouse);
	eresized(0);
	for(;;){
		m = emouse();
		if(m.buttons){
			do m = emouse(); while(m.buttons);
			i = (m.xy.x - screen->r.min.x) / 48 * y + (screen->r.max.y - m.xy.y) / 48 ;
			if(ptinrect(m.xy, screen->r) && a[i] != -1
			&& ((i + 1) % y && a[i + 1] == a[i] || i + y < x * y && a[i + y] == a[i]
			|| i % y && a[i - 1] == a[i] || i >= y && a[i - y] == a[i])){
				score = 0;
				flood(i, a[i]);
				for(i = x * y - 1; i >= 0; i--)
					if(a[i] == -2){
						score++;
						for(j = i; (j + 1) % y; j++) a[j] = a[j + 1];
						a[j] = -1;
					}
				total += score * (score - 1);
				for(i = (x - 2) * y; i >= 0; i -= y)
					if(a[i] == -1){
						for(j = i; j < x * y - y; j++) a[j] = a[j + y];
						while(j < x * y) a[j++] = -1;
					}
				for(i = 0; i < x * y; i++)
					if(a[i] >= 0
					&& ((i + 1) % y && a[i + 1] == a[i]
					|| i + y < x * y && a[i + y] == a[i]
					|| i % y && a[i - 1] == a[i]
					|| i >= y && a[i - y] == a[i])) break;
				if(i == x * y){
					fprint(1, "Dimensions: %d x %d\nColours: %d\nScore: %d\n", x, y, c, total);
					exits(nil);
				}
				eresized(0);
			}
		}
	}
}