/*
 *   IRC - Internet Relay Chat, modules/m_join.c
 *
 *   Copyright (C) 2000-2003 TR-IRCD Development
 *
 *   Copyright (C) 1990 Jarkko Oikarinen and
 *                      University of Oulu, Co Center
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2, or (at your option)
 *   any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include "struct.h"
#include "common.h"
#include "sys.h"
#include "numeric.h"
#include "channel.h"
#include "msg.h"
#include "h.h"
#include "s_conf.h"

static char *newCliSJOINFmt = "%T %s";

static struct Message _msgtab[] = {
    {MSG_JOIN, 0, MAXPARA, M_SLOW, 0L,
     m_unregistered, m_join, m_join, m_join, m_ignore}
};

static char *token = TOK1_JOIN;

#ifndef STATIC_MODULES

char *_version = "$Revision: 1.7 $";

void _modinit(void)
{
    mod_add_cmd(_msgtab);
    tok1_msgtab[(u_char) *token].msg = _msgtab;
}

void _moddeinit(void)
{
    mod_del_cmd(_msgtab);
    tok1_msgtab[(u_char) *token].msg = NULL;
}
#else
void m_join_init(void)
{
    mod_add_cmd(_msgtab);
    tok1_msgtab[(u_char) *token].msg = _msgtab;
}
#endif

/*
 * * m_join * parv[0] = sender prefix *       parv[1] = channel *
 * parv[2] = channel password (key) 
 */
int m_join(aClient *cptr, aClient *sptr, int parc, char *parv[])
{
    static char jbuf[BUFSIZE];
    dlink_node *lp;
    aChannel *chptr;
    char *name, *key = NULL;
    int i, flags = 0, chanlen = 0;
    char *p = NULL, *p2 = NULL;
    int newchan = 1;

    int successful_join_count = 0;

    if (!(sptr->user))
	return 0;

    if (parc < 2 || *parv[1] == '\0') {
	send_me_numeric(sptr, ERR_NEEDMOREPARAMS, MSG_JOIN);
	return 0;
    }

    *jbuf = '\0';
    /*
     * * Rebuild list of channels joined to be the actual result of the *
     * JOIN.  Note that "JOIN 0" is the destructive problem.
     */
    for (i = 0, name = strtoken(&p, parv[1], ","); name; name = strtoken(&p, (char *) NULL, ",")) {
	/*
	 * pathological case only on longest channel name. * If not dealt
	 * with here, causes desynced channel ops * since ChannelExists()
	 * doesn't see the same channel * as one being joined. cute bug.
	 * Oct 11 1997, Dianora/comstud
	 */
	if (!check_channelname(sptr, (unsigned char *) name))
	    continue;

	chanlen = strlen(name);
	if (chanlen > CHANNELLEN) {
	    name[CHANNELLEN] = '\0';
	    chanlen = CHANNELLEN;
	}
	if (*name == '&' && !MyConnect(sptr))
	    continue;
	if (*name == '0' && !atoi(name))
	    *jbuf = '\0';
	else if (!IsChannelName(name)) {
	    if (MyClient(sptr))
		send_me_numeric(sptr, ERR_NOSUCHCHANNEL, name);
	    continue;
	}
	if (*jbuf)
	    strncat(jbuf, ",", 1);
	strncat(jbuf, name, chanlen);
    }

    /*
     * (void)strcpy(parv[1], jbuf);
     */

    p = NULL;
    if (parv[2])
	key = strtoken(&p2, parv[2], ",");
    parv[2] = NULL;		/* for m_names call later, parv[parc] * must == NULL */

    for (name = strtoken(&p, jbuf, ","); name;
	 key = (key) ? strtoken(&p2, NULL, ",") : NULL, name = strtoken(&p, NULL, ",")) {

	/*
	 * * JOIN 0 sends out a part for all channels a user * has
	 * joined.
	 */
	if (*name == '0' && !atoi(name)) {
	    if (sptr->user->channel.head == NULL)
		continue;
	    lp = sptr->user->channel.head;
	    while (lp) {
		chptr = lp->data;
		lp = lp->next;
		sendto_channel_butserv(chptr, sptr, TOK1_PART, 0, "");
		remove_user_from_channel(sptr, chptr);
	    }
	    if (ServerOpts.anti_spambot) {
		if (MyConnect(sptr) && !IsAnOper(sptr)) {
		    if (sptr->count_join_part >= GeneralOpts.spam_num) {
			sendto_lev(SPAM_LEV, "User %^C is a possible spambot", sptr);
			sptr->oper_warn_count_down = ServerOpts.oper_spam_countdown;
		    } else {
    int t_delta;

			if ((t_delta =
			     (NOW - sptr->last_part_time)) >
			    ServerOpts.join_leave_count_expire_time) {
    int decrement_count;

			    decrement_count = (t_delta / ServerOpts.join_leave_count_expire_time);
			    if (decrement_count > sptr->count_join_part)
				sptr->count_join_part = 0;
			    else
				sptr->count_join_part -= decrement_count;
			} else {
			    if ((NOW - (sptr->last_join_time)) < GeneralOpts.spam_time)
				sptr->count_join_part++;
			}
			sptr->last_part_time = NOW;
		    }
		}
	    }
	    sendto_match_servs(NULL, sptr, TOK1_JOIN, "0");
	    continue;
	}

	if (MyConnect(sptr)) {
	    if ((sptr->user->joined >= ChannelConf.max_channels_per_user) && 
		(!IsAnOper(sptr) || (sptr->user->joined >= ChannelConf.max_channels_per_user * 3))) {
		send_me_numeric(sptr, ERR_TOOMANYCHANNELS, name);
		if (ServerOpts.anti_spambot && successful_join_count)
		    sptr->last_join_time = NOW;
		return 0;
	    }
	    if (ServerOpts.anti_spambot) {
		successful_join_count++;
		if ((sptr->count_join_part >= GeneralOpts.spam_num)) {
		    if (sptr->oper_warn_count_down > 0)
			sptr->oper_warn_count_down--;
		    else
			sptr->oper_warn_count_down = 0;
		    if (sptr->oper_warn_count_down == 0) {
			sendto_lev(SPAM_LEV, "User %^C trying to join %s is a possible spambot", sptr, name);
			sptr->oper_warn_count_down = ServerOpts.oper_spam_countdown;
		    }
		    return 0;
		    /* Don't actually JOIN anything, but don't let spambot know that */
		}
	    }
	}

	chptr = create_channel(sptr, name, &newchan, 1);
	if (!chptr)
	    continue;

	/*
	 * local client is first to enter previously nonexistent
	 * channel so make them (rightfully) the Channel Operator.
	 */

	flags = newchan ? CHFL_CHANOP : 0;
        if (GeneralOpts.split)
            flags = 0;

	if (MyConnect(sptr) && (i = can_join(sptr, chptr, key))) {
	    if (i == -2)
		continue;
	    send_me_numeric(sptr, i, chptr->chname);
	    if (ServerOpts.anti_spambot && (successful_join_count > 0))
		successful_join_count--;
	    continue;
	}
	if (IsMember(sptr, chptr))
	    continue;

	/*
	 * only complain when the user can join the channel, 
	 * the channel is being created by this user,
	 * and this user is not allowed to be an op. - lucas 
	 */

	if (!add_user_to_channel(chptr, sptr, flags))
	    continue;

	if (!(*chptr->chname == '&')) {

	    if (MyClient(sptr) && flags == CHFL_CHANOP) {
		char *cmodes_sm = NULL;
		chptr->tsval = timeofday;
		if (ChannelConf.default_extended_topic_limitation)
		    cmodes_sm = "+Tn";
		else
		    cmodes_sm = "+tn";

		/*
		 * we keep channel "creations" to the server sjoin format,
		 * so we can bounce modes and stuff if our ts is older. 
		 */

		sendto_serv_butone(cptr, &me, TOK1_SJOIN, "%T %H %s :@%s",
				       chptr, chptr, cmodes_sm, parv[0]);
		sendto_service(SERVICE_SEE_JOINS, 0, sptr, chptr, TOK1_JOIN, "");
	    } else if (MyClient(sptr)) {
		sendto_serv_butone(cptr, sptr, TOK1_SJOIN, newCliSJOINFmt, chptr, chptr->chname);
		sendto_service(SERVICE_SEE_JOINS, 0, sptr, chptr, TOK1_JOIN, "");
	    } else {
		sendto_match_servs(chptr, cptr, TOK1_JOIN, ":%H", chptr);
	    }
	}

	/*
	 * notify all other users on the new channel
	 */
	sendto_channel_butserv_short(chptr, sptr, TOK1_JOIN);

	if (flags == CHFL_CHANOP) {
	    char *cmodes_sm = NULL;
            
	    if (ChannelConf.default_extended_topic_limitation)
                cmodes_sm = "+Tn";
            else
                cmodes_sm = "+tn";
	    sendto_channel_butserv(chptr, &me, TOK1_MODE, 0, "%s", cmodes_sm);
	    /*
	     * In the past, we used to send MODE_TOPICLIMIT here. This is
	     * now changed. MODE_EXTOPIC leads into, that no user in the 
	     * channel, who is not +u or +a cannot set the topic. Being
	     * an op does not do anything.
	     * This behavior was required, since some people were joining
	     * channels and setting a new topic, before ChanServ was able
	     * to set the mode, since Services uses MergeChannelModes feature
	     * to set as many modes as possible in a single line, and this
	     * requires a delay.
	     *
	     * -TimeMr14C
	     */
	    chptr->mode.mode |= MODE_NOPRIVMSGS;
	    chptr->mode.mode |= (ChannelConf.default_extended_topic_limitation ? MODE_EXTOPIC : MODE_TOPICLIMIT);
	}
	if (MyClient(sptr)) {
	    del_invite(sptr, chptr);
	    if (chptr->topic[0] != '\0') {
		send_me_numeric(sptr, RPL_TOPIC, chptr->chname, chptr->topic);
		send_me_numeric(sptr, RPL_TOPICWHOTIME, chptr->chname,
				IsChanHideOps(chptr) ? chptr->chname : chptr->
				topic_nick, chptr->topic_time);
	    }
	    send_names(sptr, chptr);
	}
    }

    if (ServerOpts.anti_spambot)
	if (MyConnect(sptr) && successful_join_count)
	    sptr->last_join_time = NOW;
    return 0;
}