#include <u.h>
#include <libc.h>
#include <auth.h>
#include "chat.h"

// XXX - make these parameters?
extern int debug;
extern char servername[128];

#define RLEN 1024
#define TIMEOUT (60*1000)

int chat(int ifd, int ofd, char *chatfile)
{
	int chatfd, lineno, nb;
	char *script, *p, *s, response[RLEN];
	Dir *dir;
	UserPasswd *up;

	if ((chatfd = open(chatfile, OREAD)) < 0)
		sysfatal("cannot open %s: %r", chatfile);

	if ((dir = dirfstat(chatfd)) == nil)
		sysfatal("cannot fstat %s: %r",chatfile);

	script = (char *)malloc(dir->length + 1);
	assert(script);

	if ((nb = read(chatfd, script, dir->length)) < 0)
		sysfatal("cannot read chatfile %s: %r", chatfile);
	assert(nb == dir->length);
	script[dir->length] = '\0';
	free(dir);
	close(chatfd);

	p = script;
	lineno = 0;
	while (1) {
		char *_args[3];

		if ((s = strchr(p, '\n')) == nil)
			break;
		*s++ = '\0';
	
		lineno++;

		if (*p == '#') {
			p = s; 
			continue;
		}

		if (tokenize(p, _args, 3) != 2)
			sysfatal("invalid line %d (line expected: 'send' 'expect')", 
					lineno);

		if (strcmp(_args[0], "USER") == 0) {
			up = getuserpass();
			_args[0] = up->user;
		}
		else if (strcmp(_args[0], "PASSWD") == 0) {
			up = getuserpass();
			_args[0] = up->passwd;
		}
		else if (strcmp(_args[0], "SERVER") == 0) {
			_args[0] = servername;
		}
		else if (strcmp(_args[0], "CRNL") == 0) {
			_args[0] = "\r\n";
		}
		else if (strcmp(_args[0], "CR") == 0) {
			_args[0] = "\r";
		}
		else if (strcmp(_args[0], "NL") == 0) {
			_args[0] = "\n";
		}
		else if (strcmp(_args[0], "PAUSE") == 0) {
			sleep(5000);
			_args[0] = "";
		}

		if (debug)
			fprint(2, "sending “%s”, expecting “%s”\n", _args[0], _args[1]);

		if ((nb = write(ofd, _args[0], strlen(_args[0]))) < 0)
			sysfatal("cannot write %ss: %r", _args[0]);
		assert(nb == strlen(_args[0]));

		if (strlen(_args[1]) > 0) {
			char *rp = response;
			char *ep = response+sizeof(response)-1;
			int found = 0;

			alarm(TIMEOUT);
			while ((nb = read(ifd, rp, 1)) >= 0 && rp < ep) {
				if (debug)
					fprint(2, "response %02x %c\n", *rp, *rp);
				rp += nb;
				*rp = 0;
				found = cistrstr(response, _args[1]) != nil;
				if (found) {
					if (debug) fprint(2, "found “%s”\n", response);
					break;
				}
			}
			alarm(0);
			if (nb < 0)
				sysfatal("cannot read response from: %r");
			if (nb == 0)
				sysfatal("eof on input?\n");
			if (!found)
				sysfatal("expected %s, got %s\n", _args[1], response);
		}
		p = s;
	}
	free(script);
	return 1;
}