/* See LICENSE file for license details. */
#include <ctype.h>
#include <errno.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>

static char *host = "irc.oftc.net";
static char *port = "ircd";
static char *password;
static char nick[32];
static char bufin[4096];
static char bufout[4096];
static time_t trespond;
static FILE *srv;

#include "util.c"

static void
pout(char *channel, char *fmt, ...) {
    static char timestr[18];
    time_t t;
    va_list ap;

    va_start(ap, fmt);
    vsnprintf(bufout, sizeof bufout, fmt, ap);
    va_end(ap);
    t = time(NULL);
    strftime(timestr, sizeof timestr, "%D %R", localtime(&t));
    fprintf(stdout, "%s: %s  %s\n", channel, timestr, bufout);
}

static void
sout(char *fmt, ...) {
    va_list ap;

    va_start(ap, fmt);
    vsnprintf(bufout, sizeof bufout, fmt, ap);
    va_end(ap);
    fprintf(srv, "%s\r\n", bufout);
}

static void
parsein(char *s) {
    if(s[0] == '\0')
        return;
    skip(s, '\n');
    sout("%s", s);
    pout(nick, "> %s", s);
}

static void
parsesrv(char *cmd) {
    char *usr, *par, *txt;

    usr = host;
    if(!cmd || !*cmd)
        return;
    if(cmd[0] == ':') {
        usr = cmd + 1;
        cmd = skip(usr, ' ');
        if(cmd[0] == '\0')
            return;
        skip(usr, '!');
    }
    skip(cmd, '\r');
    par = skip(cmd, ' ');
    txt = skip(par, ':');
    trim(par);
    if(!strcmp("PONG", cmd))
        return;
    if(!strcmp("PRIVMSG", cmd))
        pout(par, "<%s> %s", usr, txt);
    else if(!strcmp("PING", cmd))
        sout("PONG %s", txt);
    else {
        pout(usr, ">< %s (%s): %s", cmd, par, txt);
        if(!strcmp("NICK", cmd) && !strcmp(usr, nick))
            strlcpy(nick, txt, sizeof nick);
    }
}

int
main(int argc, char *argv[]) {
    int i, c;
    struct timeval tv;
    const char *user = getenv("USER");
    fd_set rd;

    strlcpy(nick, user ? user : "unknown", sizeof nick);
    for(i = 1; i < argc; i++) {
        c = argv[i][1];
        if(argv[i][0] != '-' || argv[i][2])
            c = -1;
        switch(c) {
        case 'h':
            if(++i < argc) host = argv[i];
            break;
        case 'p':
            if(++i < argc) port = argv[i];
            break;
        case 'n':
            if(++i < argc) strlcpy(nick, argv[i], sizeof nick);
            break;
        case 'k':
            if(++i < argc) password = argv[i];
            break;
        case 'v':
            eprint("sic-"VERSION", © 2005-2009 Kris Maglione, Anselm R. Garbe, Nico Golde\n");
        default:
            eprint("usage: sic [-h host] [-p port] [-n nick] [-k keyword] [-v]\n");
        }
    }
    /* init */
    i = dial(host, port);
    srv = fdopen(i, "r+");
    /* login */
    if(password)
        sout("PASS %s", password);
    sout("NICK %s", nick);
    sout("USER %s localhost %s :%s", nick, host, nick);
    fflush(srv);
    setbuf(stdout, NULL);
    setbuf(srv, NULL);
    for(;;) { /* main loop */
        FD_ZERO(&rd);
        FD_SET(0, &rd);
        FD_SET(fileno(srv), &rd);
        tv.tv_sec = 120;
        tv.tv_usec = 0;
        i = select(fileno(srv) + 1, &rd, 0, 0, &tv);
        if(i < 0) {
            if(errno == EINTR)
                continue;
            eprint("sic: error on select():");
        }
        else if(i == 0) {
            if(time(NULL) - trespond >= 300)
                eprint("sic shutting down: parse timeout\n");
            sout("PING %s", host);
            continue;
        }
        if(FD_ISSET(fileno(srv), &rd)) {
            if(fgets(bufin, sizeof bufin, srv) == NULL)
                eprint("sic: remote host closed connection\n");
            parsesrv(bufin);
            trespond = time(NULL);
        }
        if(FD_ISSET(0, &rd)) {
            if(fgets(bufin, sizeof bufin, stdin) == NULL)
                eprint("sic: broken pipe\n");
            parsein(bufin);
        }
    }
    return 0;
}