#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <unistd.h>
#include <assert.h>
#include <string.h>
#include <fcntl.h>

#include "mm_help.h"

int readline (int fd, char * buf, int len)
{
	int ret, off=0;
	while (len > 1) {
		ret = read (fd, buf+off, len-1);
		if (ret < 0) {
			perror ("read");
			exit (1);
		}
		if (ret == 0) {
			fprintf (stderr, "Unexpected EOF\n");
			exit (1);
		}
		len -= ret;
		off += ret;
		if (buf[off-1] == '\n') {
			buf[off] = 0;
			assert (off >= 2 && buf[off-2] == '\r');
			// fprintf (stderr, "READ: %s", buf);
			return 1;
		}
	}
	(*buf) = 0;
	return 0;
}

void writeline (int fd, char * buf)
{
	int len = strlen (buf);
	int ret;
	// fprintf (stderr, "WRITE: %s", buf);
	assert (len >= 2 && buf[len-1] == '\n' && buf[len-2] == '\r');
	while (len) {
		ret = write (fd, buf, len);
		if (ret < 0) {
			perror ("write");
			exit (1);
		}
		buf += ret;
		len -= ret;
	}
}

int readreply (int fd, char * buf, int len)
{
	int reply = -1, off = -1;
	if (!readline (fd, buf, len)) {
		fprintf (stderr, "Bad or incomplete line\n");
		exit (1);
	}
	sscanf (buf, "%d %n", &reply, &off);
	if (reply < 100 || reply > 500 || off != 4) {
		fprintf (stderr, "Reply code missing or out of range\n");
		exit (1);
	}
	return reply;
}

void parse_hello (char * buf, int * maxc, int * maxl)
{
	int off=-1;
	sscanf (buf, "MMSERVER colmax=%d lenmax=%d\r\n%n", maxc, maxl, &off);
	if (off < 0 || buf[off]) {
		fprintf (stderr, "Badly formatted reply\n");
		exit (1);
	}
	if ((*maxc) < 2 || (*maxl) < 2) {
		fprintf (stderr, "Bad maximum colour/length\n");
		exit (1);
	}
}

void parse_bw (char * buf, int *b, int * w)
{
	int off = -1;
	sscanf (buf, "Blacks=%d Whites=%d\r\n%n", b, w, &off);
	if (off < 0 || buf[off]) {
		fprintf (stderr, "Badly formatted reply\n");
		exit (1);
	}
	if ((*b) < 0 || (*w) < 0) {
		fprintf (stderr, "Bad guess return from server\n");
		exit (1);
	}
}

void reset(int * p)
{
	int ret;
	static char buf[1000];
	writeline (p[1], "RESET\r\n");
	ret = readreply (p[0], buf, 1000);
	assert (ret == 203);
}

void doit (int * p, int c, int l)
{
	int ng, done;
	static char buf[1000];
	struct guess * guesses = NULL;
	guesses = get_guesses (c, l, 0);
	if (!guesses) {
		fprintf (stderr, "Too many posibilities for col=%d len=%d\n", c, l);
		reset (p);
		return;
	}
	ng = 0;
	done = 0;
	while (1) {
		int ret, b, w;
		struct guess *g;
		assert (guesses);
		sprintf (buf, "GUESS %s\r\n", guesses->g);
		writeline (p[1], buf);
		ng ++;
		ret = readreply (p[0], buf, 1000);
		if (ret == 205) {
			done = 1;
			break;
		}
		if (ret != 206) {
			fprintf (stderr, "Strange reply. Resetting\n");
			break;
		}
		parse_bw (buf+4, &b, &w);
		g = guesses;
		while (g->next) {
			int tb, tw;
			bw (guesses->g, g->next->g, &tb, &tw);
			if (tb != b || tw != w) {
				struct guess * tmp = g->next;
				g->next = tmp->next;
				free (tmp);
			} else {
				g = g->next;
			}
		}
		g = guesses;
		guesses = g->next;
		free (g);
	}
	while (guesses) {
		struct guess * g;
		g = guesses;
		guesses = g->next;
		free (g);
	}
	if (done) {
		printf ("Solved cols=%d len=%d after %d guesses\n", c, l, ng);
	}
}

int main ()
{
	static char buf[1000];
	int ret;
	int maxc, maxl;
	int l, c;
	int p[2];
	p[0] = open ("p2", O_RDONLY);
	if (p[0] < 0) {
		perror ("open");
		exit (1);
	}
	p[1] = open ("p1", O_WRONLY);
	if (p[1] < 0)  {
		perror ("open");
		exit (1);
	}
	ret = readreply (p[0], buf, 1000);
	assert (ret == 200);
	parse_hello (buf+4, &maxc, &maxl);
	for (l=3; l<10; l++) {
		for (c=3; c<10; c++) {
			sprintf (buf, "game FREE %d %d\r\n", c, l);
			writeline (p[1], buf);
			ret = readreply (p[0], buf, 1000);
			switch (ret) {
			case 500:
			case 501:
				fprintf (stderr, "col=%d len=%d not supported\n", c, l);
				break;
			case 201:
				doit (p,c,l);
				break;
			default:
				fprintf (stderr, "Ooops. Resetting connection\n");
				reset (p);
				break;
			}
		}
	}
	writeline (p[1], "quit\r\n");
	ret = readreply (p[0], buf, 1000);
	assert (ret == 207);
	return 0;
}