#include <u.h>
#include <libc.h>
#include <draw.h>
#include <cursor.h>
#include <event.h>
enum{PITS = 14, HALFPITS = PITS >> 1, SEEDS = 4, Eremote = 8,
	MSG = 8, MSGLEN = 128, RAD = 30, GAP = 8, ZZZ = 400};
Image *ground, *pit, *hl[2];
Point o[PITS], compass[4];
Rectangle r[3];
char msg[MSG][MSGLEN], p[2][64];
int b[PITS], t, msgn;
void drawpit(int i, Image *color){
	char buf[4];
	fillellipse(screen, o[i], RAD, RAD, color, ZP);
	snprint(buf, 4, "%d", b[i]);
	string(screen, subpt(o[i], divpt(stringsize(font, buf), 2)), display->black, ZP, font, buf);
}
void drawpointer(void){
	Point tri[3];
	fillpoly(screen, compass, 4, 0, ground, ZP);
	if(t < 0){
		tri[0] = compass[0];
		tri[1] = compass[2];
		if(b[HALFPITS] >= b[0]){
			tri[2] = compass[1];
			fillpoly(screen, tri, 3, 0, hl[0], ZP);
		}
		if(b[0] >= b[HALFPITS]){
			tri[2] = compass[3];
			fillpoly(screen, tri, 3, 0, hl[1], ZP);
		}
	}
	else{
		tri[0] = compass[1];
		tri[1] = compass[3];
		tri[2] = compass[!t << 1];
		fillpoly(screen, tri, 3, 0, hl[t], ZP);
	}
}
void drawlabel(int i){
	draw(screen, r[i], ground, nil, ZP);
	string(screen,
		addpt(r[i].min, Pt(Dx(r[i]) - stringwidth(font, p[i]) >> 1, 0)),
		display->black, ZP, font, p[i]);
}
void drawmsgs(void){
	Point o; int i;
	draw(screen, r[2], display->white, nil, ZP);
	for(o = r[2].min, i = 0; i < MSG; o.y += font->height)
		string(screen, o, display->black, ZP, font, msg[msgn + i++ & MSG - 1]);
}
void eresized(int i){
	if(i && getwindow(display, Refnone) < 0)
		sysfatal("can't reattach to window");
	if((!i || Dy(screen->r) != 6 * (RAD + GAP) + (MSG + 2) * font->height)
	&& (i = open("/dev/wctl", OWRITE)) >= 0){
		fprint(i, "resize -dy %d",
			6 * (RAD + GAP) + (MSG + 2) * font->height + 2 * Borderwidth);
		close(i);
	}
	draw(screen, screen->r, ground, nil, ZP);
	compass[3].x = screen->r.min.x + screen->r.max.x >> 1;
	compass[3].y = screen->r.min.y + 3 * (RAD + GAP) + font->height;
	o[0] = subpt(compass[3], Pt(PITS * RAD + HALFPITS * GAP >> 1, 0));
	o[HALFPITS] = addpt(o[0], Pt(PITS * RAD + HALFPITS * GAP, 0));
	for(i = 1; i < HALFPITS; i++){
		o[i] = addpt(o[0], Pt(i * (2 * RAD + GAP), 2 * RAD + GAP));
		o[HALFPITS + i] = subpt(o[HALFPITS], Pt(i * (2 * RAD + GAP), 2 * RAD + GAP));
	}
	for(i = 0; i < PITS; i++) drawpit(i, pit);
	compass[0] = subpt(compass[3], Pt(0, RAD));	/* north */
	compass[1] = addpt(compass[3], Pt(RAD, 0));	/* east */
	compass[2] = addpt(compass[3], Pt(0, RAD));	/* south */
	compass[3] = subpt(compass[3], Pt(RAD, 0));	/* west */
	drawpointer();
	r[1] = rectaddpt(Rect(0, GAP, Dx(screen->r), GAP + font->height), screen->r.min);
	drawlabel(1);
	r[0] = rectaddpt(r[1], Pt(0, 6 * RAD + 4 * GAP + font->height));
	drawlabel(0);
	r[2] = Rect(r[0].min.x, r[0].max.y + GAP, r[0].max.x, screen->r.max.y);
	drawmsgs();
	flushimage(display, 1);
}
void flash(int n){
	drawpit(n, hl[t]);
	flushimage(display, 1);
	sleep(ZZZ);
	drawpit(n, pit);
}
void sow(int n, int animate){
	int i, mypot, yourpot;
	i = b[n];
	if(animate) flash(n);
	b[n] = 0;
	if(animate) flash(n);
	yourpot = t * HALFPITS;
	mypot = yourpot ^ HALFPITS;
	while(i--){
		n = ++n % PITS;
		n += n == yourpot;
		b[n]++;
		if(animate) flash(n);
	}
	if((n + yourpot) % PITS < HALFPITS && b[n] == 1 && b[PITS - n]){/* capture */
		b[n] = 0;
		b[mypot]++;
		if(animate){
			flash(n);
			flash(mypot);
		}
		b[mypot] += b[PITS - n];	/* capture */
		b[PITS - n] = 0;
		if(animate){
			flash(PITS - n);
			flash(mypot);
		}
	}
	t ^= n != mypot;
	for(i = 1; i < HALFPITS && !b[i]; i++);
	if(i == HALFPITS){	/* game over */
		t = 1;
		for(i++; i < PITS; i++)
			if(b[i]){
				b[0] += b[i];
				b[i] = 0;
				if(animate){
					flash(i);
					flash(0);
				}
			}
		t = -1;
	}
	else{
		for(i = HALFPITS + 1; i < PITS && !b[i]; i++);
		if(i == PITS){	/* game over */
			t = 0;
			for(i = 1; i < HALFPITS; i++)
				if(b[i]){
					b[HALFPITS] += b[i];
					b[i] = 0;
					if(animate){
						flash(i);
						flash(HALFPITS);
					}
				}
			t = -1;
		}
	}
	if(t < 0){
		i = b[HALFPITS] - b[0];
		t = i == 0 ? -3 : i > 0 ? -2 : -1;
	}
	if(animate){
		drawpointer();
		flushimage(display, 1);
	}
}
void chat(void *s, int n){
	if(n >= MSGLEN) n = MSGLEN - 1;
	memmove(msg[msgn], s, n);
	msg[msgn][n] = '\0';
	msgn = msgn + 1 & MSG - 1;
	drawmsgs();
	flushimage(display, 1);
}
int αβ(int d, int α, int β, int *mv){
	int i, j, yourpot, old[PITS], oldt, v;
	yourpot = t * HALFPITS;
	if(t < 0 || d < 1) return b[yourpot ^ HALFPITS] - b[yourpot];
	for(j = 0; j < PITS; j++) old[j] = b[j];
	oldt = t;
	for(i = yourpot + 1; α < β && i >> t < HALFPITS; i++){
		if(!b[i]) continue;
		sow(i, 0);
		v = (t ^ oldt) ? -αβ(d - 1, -β, -α, nil) : αβ(d, α, β, nil);
		for(j = 0; j < PITS; j++) b[j] = old[j];
		t = oldt;
		if(v > α){
			α = v;
			if(mv != nil) *mv = i;
		}
	}
	return α;
}
void main(int argc, char **argv){
	Event e; Cursor busy = {{-1, -1},
		{0xff, 0x80, 0xff, 0x80, 0xff, 0x00, 0xfe, 0x00, 
		 0xff, 0x00, 0xff, 0x80, 0xff, 0xc0, 0xef, 0xe0, 
		 0xc7, 0xf0, 0x03, 0xf0, 0x01, 0xe0, 0x00, 0xc0, 
		 0x03, 0xff, 0x03, 0xff, 0x03, 0xff, 0x03, 0xff},
		{0x00, 0x00, 0x7f, 0x00, 0x7e, 0x00, 0x7c, 0x00, 
		 0x7e, 0x00, 0x7f, 0x00, 0x6f, 0x80, 0x47, 0xc0, 
		 0x03, 0xe0, 0x01, 0xf0, 0x00, 0xe0, 0x00, 0x40, 
		 0x00, 0x00, 0x01, 0xb6, 0x01, 0xb6, 0x00, 0x00}};
	char buf[MSGLEN], moves[HALFPITS + 1], *f, *u, *s; int i, oldt, fd = -1;
	SET(f); ARGBEGIN{
	default:
	 	sysfatal("usage: %s [-9 file] [movetext]", argv0);
	case '9':
		f = EARGF(sysfatal("bad argument to -9"));
		if((fd = open(f, ORDWR)) < 0) sysfatal("open: %r");
	}ARGEND
	if(initdraw(nil, nil, "kalah") < 0) sysfatal("initdraw: %r");
	ground = allocimage(display, Rect(0,0,1,1), screen->chan, 1, DPaleyellow);
	pit = allocimage(display, Rect(0,0,1,1), screen->chan, 1, DYellowgreen);
	hl[0] = allocimage(display, Rect(0,0,1,1), screen->chan, 1, DPalegreygreen);
	hl[1] = allocimage(display, Rect(0,0,1,1), screen->chan, 1, DPalegreen);
	if(ground == nil | pit == nil | hl[0] == nil | hl[1] == nil) sysfatal("allocimage: %r");
	u = getuser();
	einit(Emouse | Ekeyboard);
	srand(truerand());
	new: strcpy(p[0], u); strcpy(p[1], u);
	for(i = 0; i < PITS; i++) b[i] = SEEDS;
	t = b[0] = b[HALFPITS] = 0;
	eresized(0);
	if(fd >= 0){
		s = strchr(f, '\0') - 3;
		if(s >= f && !strcmp(s, "ctl")){
			buf[0] = '2'; buf[1] = '\0';
			do eenter("play first or second? [1/2]", buf, 2, &e.mouse);
				while(*buf != '1' && *buf != '2');
			s = buf + 6;
			if(*buf == '1') s = strecpy(s, buf + MSGLEN, u) + 1;
			*s = '\0';
			if((i = eenter("opponent's user name",
				s, MSGLEN + buf - s - 10, &e.mouse)) <= 0)
					sysfatal("player entry cancelled");
			if(!strcmp(s, u)) sysfatal("Play with yourself in your own time!");
			s += i;
			if(*buf == '2') s = strecpy(s + 1, buf + MSGLEN, u);
			strcpy(buf, "kalah");
			i = write(fd, buf, s - buf);
			close(fd);
			s = strecpy(buf, buf + MSGLEN, f) - 3;
			s = seprint(s, buf + MSGLEN, "%d", i);
			if((fd = open(buf, ORDWR)) < 0) sysfatal("open: %r");
			chat(buf, s - buf);
		}else chat(f, strlen(f));
		if((i = read(fd, buf, MSGLEN - 1)) < 10) sysfatal("not a kalah game?");
		buf[i] = '\0';
		if(strcmp(buf, "kalah")) sysfatal("not a kalah game!");
		strncpy(p[0], buf + 6, 63);
		for(s = buf + 6; *s++ != '\0';);
		if(s - buf >= i) sysfatal("couldn't get player 2 name");
		strncpy(p[1], s, 63);
		strcpy(buf + 3, buf + 6);
		strncpy(s - 4, " vs ", 4);
		while(*s != '\0') s++;
		chat(buf + 3, s - buf - 3);
		if(!strcmp(p[1], u)){
			strcpy(buf, p[0]);
			strcpy(p[0], p[1]);
			strcpy(p[1], buf);
			t = 1;
		}
		while(++s - buf < i && *s != ':')
			if(*s > '0' && *s < '0' + HALFPITS && b[*s - '0' + t * HALFPITS])
				sow(*s - '0' + t * HALFPITS, 0);
		if(s - buf < i){
			if(t >= 0) t = -1;
			if(buf + i > s + 2) chat(s + 2, buf + i - s - 2);
		}
		eresized(0);
		if(t >= 0 && strcmp(p[t], u)) esetcursor(&busy);
		estart(Eremote, fd, MSGLEN);
		strncpy(moves, " ", HALFPITS + 1);
	}
	else chat("new game: click user name to create ai player", 45);
	for(;;){
		if(fd < 0 && !strncmp(p[t], "ai level ", 9)){
			if(ecankbd()){
				chat("ai stopped", 10);
				while(ecankbd()) ekbd();	/* gulp */
				strcpy(p[t], u);
				drawlabel(t);
				esetcursor(nil);
				flushimage(display, 1);
				continue;
			}
			esetcursor(&busy);
			sleep(ZZZ);
			for(fd = 0, i = t * HALFPITS + 1; i >> t < HALFPITS; i++) if(b[i]) fd++;
			for(fd = nrand(fd), i = t * HALFPITS + 1; !b[i] || fd--; i++);
			αβ(p[t][9] - '1', -PITS * SEEDS, PITS * SEEDS, &i);
			sow(i, 1);
			if(t < 0) goto gameover;
			esetcursor(nil);
		}
		else switch(event(&e)){
		case Eremote:
			if(e.n > 1 && e.data[0] == ' '){
				if(e.data[1] == ':'){
					esetcursor(nil);
					if(t >= 0) t = -3;
					if(e.n > 2) chat(e.data + 3, e.n - 3);
					continue;
				}
				if(e.n == strlen(moves) && !memcmp(moves, e.data, e.n)){
					strncpy(moves, " ", HALFPITS + 1);
					continue;
				}
				if(t < 0) continue;
				for(i = 1; i < e.n; i++)
					if(e.data[i] > '0' && e.data[i] < '0' + HALFPITS
					&& b[e.data[i] - '0' + t * HALFPITS])
						sow(e.data[i] - '0' + t * HALFPITS, 1);
				if(t < 0){
					if(t > -3) fprint(fd, " : %s won", p[t & 1]);
					else write(fd, " : draw", 7);
					continue;
				}
				esetcursor(strcmp(p[t], u) ? &busy : nil);
			}
			else chat(e.data, e.n);
			break;
		case Emouse:
			if(!e.mouse.buttons || strcmp(p[t], u) || t < 0) break;
			do eread(Emouse, &e); while(e.mouse.buttons);
			if(fd < 0 && (ptinrect(e.mouse.xy, r[i = 0]) || ptinrect(e.mouse.xy, r[i = 1]))){
				*buf = '\0';
				eenter("ai level ? [0–9]", buf, 2, &e.mouse);
				if(*buf == '0') strcpy(p[i], u);
				else if(*buf >= '1' && *buf <= '9'){
					strcpy(p[i], "ai level x");
					p[i][9] = *buf;
				}
				else continue;
				drawlabel(i);
				s = strecpy(buf, buf + MSGLEN, p[0]);
				s = strecpy(s, buf + MSGLEN, " vs ");
				s = strecpy(s, buf + MSGLEN, p[1]);
				chat(buf, s - buf);
			}
			else for(i = t * HALFPITS + 1; i >> t < HALFPITS; i++)
				if(sqrt((e.mouse.xy.x - o[i].x) * (e.mouse.xy.x - o[i].x)
				+ (e.mouse.xy.y - o[i].y) * (e.mouse.xy.y - o[i].y))
				< RAD && b[i]){
					oldt = t;
					sow(i, 1);
					if(fd >= 0){
						for(s = moves + 1; *s; s++);
						*s = '0' + i - oldt * HALFPITS;
						if(oldt != t)
							write(fd, moves, s - moves + 1);
						esetcursor(strcmp(p[t], u) ? &busy : nil);
					}
					if(t < 0 && fd < 0){gameover:
						esetcursor(nil);
						strcpy(buf, " : ");
						if(t > -3){
							s = strecpy(buf + 3, buf + MSGLEN, p[t & 1]);
							s = strecpy(s, buf + MSGLEN, " won");
						}
						else s = strcpy(buf + 3, "draw") + 4;
						chat(buf + 3, s - buf - 3);
						chat("press any key for a new game or DEL to quit", 43);
						if(ekbd() == 127) exits(nil);
						goto new;
					}
					break;
				}
			break;
		case Ekeyboard:
			switch(e.kbdc){
			case 127: exits(nil);
			case 'n': if(fd < 0) goto new;
			default:
				if(fd >= 0){
					buf[0] = e.kbdc; buf[1] = '\0';
					if((i = eenter("message", buf, MSGLEN, &e.mouse)) < 1) break;
					if(buf[0] == ' ') buf[0] = '_';
					if(!strcmp(buf, "!resign")) fprint(fd, " : %s resigned", u);
					else write(fd, buf, i);
				}
				break;
			}
			break;
		}
	}
}