#include <u.h>
#include <libc.h>
#include <draw.h>
#include <thread.h>
#include <mouse.h>
#include <keyboard.h>
enum{RESIZE, MOUSE, KEYBOARD};
Image *bunny;
int state, win, dummy, g0, g1, won[2], played[2];
char *s0 = "I can reveal that there is no bunny behind door x.";
char *s1 = "You may stick with door m or switch to door n. What'll it be?";
Rectangle
doorrect(int n){
	Point p;
	p.x = screen->r.min.x + screen->r.max.x - bunny->r.max.x >> 1;
	if(n < 1)
		p.x = screen->r.min.x + p.x - bunny->r.max.x >> 1;
	if(n > 1)
		p.x = p.x + screen->r.max.x >> 1;
	p.y = screen->r.min.y + screen->r.max.y - bunny->r.max.y >> 1;
	return rectaddpt(bunny->r, p);
}
void
drawdoor(int n){
	Rectangle r;
	r = doorrect(n);
	if(n == win && state == 3){
		draw(screen, r, bunny, nil, ZP);
		return;
	}
	draw(screen, r, display->black, nil, ZP);
	if(n == dummy || state == 2 && n != win)
		return;
	r = insetrect(r, 12);
	draw(screen, r, display->white, nil, ZP);
}
int
indoor(Point p){
	if(ptinrect(p, doorrect(0)))
		return 0;
	if(ptinrect(p, doorrect(1)))
		return 1;
	if(ptinrect(p, doorrect(2)))
		return 2;
	return -1;
}
void
one(int n){
	g0 = n;
	if(n == win)
		dummy = (n + 1 + (lrand() & 1)) % 3;
	else
		for(dummy = 0; dummy == n || dummy == win; dummy++)
			;
	for(g1 = 0; g1 == g0 || g1 == dummy; g1++)
		;
	s0[48] = '1' + dummy;
	s1[24] = '1' + g0;
	s1[44] = '1' + g1;
	state = 1;
}
void
two(int n){
	if(n == win){
		state = 3;
		won[n == g1]++;
	}else
		state = 2;
	played[n == g1]++;
}
void
zero(void){
	state = 0;
	dummy = -1;
	win = nrand(3);
}
void
threadmain(int, char**){
	Keyboardctl *kctl;
	Mousectl *mctl;
	uchar *d;
	Rune ᚱ;
	int i, j;
	Alt a[] = {
		[RESIZE]{nil, nil, CHANRCV},
		[MOUSE]{nil, nil, CHANRCV},
		[KEYBOARD]{nil, &ᚱ, CHANRCV},
		{nil, nil, CHANEND}
	};
	if(initdraw(nil, nil, "Monty Hall") < 0)
		sysfatal("initdraw: %r");
	d = malloc(256 * 320);
	i = open("/lib/bunny.bit", OREAD);
	if(d == nil || i < 0 || (bunny = readimage(display, i, 0)) == nil)
		sysfatal("sad bunny");
	close(i);
	unloadimage(bunny, Rect(24, 5, 152, 165), d, 128 * 160);
	freeimage(bunny);
	bunny = allocimage(display, Rect(0, 0, 256, 320), GREY8, 0, DNofill);
	for(i = 159; i >= 0; i--)
		for(j = 127; j >= 0; j--)
			d[i << 9 | j << 1] =
			d[i << 9 | j << 1 | 1] =
			d[2 * i + 1 << 8 | j << 1] =
			d[2 * i + 1 << 8 | j << 1 | 1] = d[i << 7 | j];
	loadimage(bunny, bunny->r, d, 256 * 320);
	free(d);
	mctl = initmouse(nil, screen);
	kctl = initkeyboard(nil);
	if(mctl == nil || kctl == nil)
		sysfatal("init: %r");
	a[RESIZE].c = mctl->resizec;
	a[MOUSE].c = mctl->c;
	a[MOUSE].v = &mctl->Mouse;
	a[KEYBOARD].c = kctl->c;
	srand(truerand());
	zero();
	sendul(mctl->resizec, 1);
	while(9){
		switch(alt(a)){
		case RESIZE:
			getwindow(display, Refnone);
			break;
		case MOUSE:
			if(mctl->buttons != 1)
				continue;
			i = indoor(mctl->xy);
			while(alt(a) != MOUSE || mctl->buttons)
				;
			switch(state){
			case 0:
				if(i < 0 || i != indoor(mctl->xy))
					continue;
				one(i);
				break;
			case 1:
				if(i < 0 || i == dummy || i != indoor(mctl->xy))
					continue;
				two(i);
				break;
			default:
				zero();
				break;
			}
			break;
		case KEYBOARD:
			switch(ᚱ){
			case Kdel: case 'q':
				print("games played: %d\n", played[0] + played[1]);
				if(played[0])
					print("games won by sticking to your guns: %d / %d (%g%%)\n",
						won[0], played[0], 100.0 * won[0] / played[0]);
				if(played[1])
					print("games won by swapping doors: %d / %d (%g%%)\n",
						won[1], played[1], 100.0 * won[1] / played[1]);
				threadexitsall(nil);
			case '1': case '2': case '3':
				i = ᚱ - '1';
				if(state == 0){
					one(i);
					break;
				}
				if(state == 1){
					two(i);
					break;
				}
			default:
				if(state < 2)
					continue;
				zero();
				break;
			}
		}
		draw(screen, screen->r, display->white, nil, ZP);
		drawdoor(0);
		drawdoor(1);
		drawdoor(2);
		switch(state){
		case 0:
			string(screen, screen->r.min, display->black, ZP, font,
				"Choose the door you think the bunny is behind.");
			break;
		case 1:
			string(screen, screen->r.min, display->black, ZP, font, s0);
			string(screen, Pt(screen->r.min.x, screen->r.min.y + font->height),
				display->black, ZP, font, s1);
			break;
		case 2:
			string(screen, screen->r.min, display->black, ZP, font,
				"Sorry, no bunny there! Press q to quit or any other key to play again.");
			break;
		case 3:
			string(screen, screen->r.min, display->black, ZP, font,
				"Nice! you found the bunny! Press q to quit or any other key to play again.");
			break;
		}
		flushimage(display, 1);
	}
}