/*
 *  ircd-ratbox: A slightly useful ircd.
 *  m_links.c: Shows what servers are currently connected.
 *
 *  Copyright (C) 1990 Jarkko Oikarinen and University of Oulu, Co Center
 *  Copyright (C) 1996-2002 Hybrid Development Team
 *  Copyright (C) 2002-2005 ircd-ratbox development team
 *
 *  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 of the License, 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 *  USA
 *
 */

#include "stdinc.h"
#include "client.h"
#include "match.h"
#include "ircd.h"
#include "numeric.h"
#include "s_serv.h"
#include "send.h"
#include "s_conf.h"
#include "msg.h"
#include "parse.h"
#include "modules.h"
#include "hook.h"
#include "scache.h"

static int m_links(struct Client *, struct Client *, int, const char **);
static int mo_links(struct Client *, struct Client *, int, const char **);
static char * clean_string(char *dest, const unsigned char *src, size_t len);

struct Message links_msgtab = {
    "LINKS", 0, 0, 0, MFLG_SLOW,
    {mg_unreg, {m_links, 0}, {mo_links, 0}, mg_ignore, mg_ignore, {mo_links, 0}}
};

int doing_links_hook;

mapi_clist_av1 links_clist[] = { &links_msgtab, NULL };
mapi_hlist_av1 links_hlist[] = {
    { "doing_links",	&doing_links_hook },
    { NULL, NULL }
};

DECLARE_MODULE_AV1(links, NULL, NULL, links_clist, links_hlist, NULL, "$Revision: 254 $");

/*
 * m_links - LINKS message handler
 *      parv[1] = servername mask
 * or
 *      parv[1] = server to query
 *      parv[2] = servername mask
 */
static int
m_links(struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
{
    if(ConfigServerHide.flatten_links && !IsExemptShide(source_p))
        scache_send_flattened_links(source_p);
    else
        mo_links(client_p, source_p, parc, parv);

    return 0;
}

static int
mo_links(struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
{
    const char *mask = "";
    struct Client *target_p;
    char clean_mask[2 * HOSTLEN + 4];
    hook_data hd;

    rb_dlink_node *ptr;

    if(parc > 2) {
        if(strlen(parv[2]) > HOSTLEN)
            return 0;
        if(hunt_server(client_p, source_p, ":%s LINKS %s :%s", 1, parc, parv)
           != HUNTED_ISME)
            return 0;

        mask = parv[2];
    } else if(parc == 2)
        mask = parv[1];

    if(*mask)		/* only necessary if there is a mask */
        mask = collapse(clean_string
                        (clean_mask, (const unsigned char *) mask, 2 * HOSTLEN));

    hd.client = source_p;
    hd.arg1 = mask;
    hd.arg2 = NULL;

    call_hook(doing_links_hook, &hd);

    RB_DLINK_FOREACH(ptr, global_serv_list.head) {
        target_p = ptr->data;

        if(*mask && !match(mask, target_p->name))
            continue;

        /* We just send the reply, as if theyre here theres either no SHIDE,
         * or theyre an oper..
         */
        sendto_one_numeric(source_p, RPL_LINKS, form_str(RPL_LINKS),
                           target_p->name, target_p->servptr->name,
                           target_p->hopcount,
                           target_p->info[0] ? target_p->info : "(Unknown Location)");
    }

    sendto_one_numeric(source_p, RPL_ENDOFLINKS, form_str(RPL_ENDOFLINKS),
                       EmptyString(mask) ? "*" : mask);

    return 0;
}

static char *
clean_string(char *dest, const unsigned char *src, size_t len)
{
    char *d = dest;
    s_assert(0 != dest);
    s_assert(0 != src);

    if(dest == NULL || src == NULL)
        return NULL;

    while (*src && (len > 1)) {
        if(*src & 0x80) {	/* if high bit is set */
            *d++ = '.';
            --len;
            if(len <= 1)
                break;
        } else if(!IsPrint(*src)) {	/* if NOT printable */
            *d++ = '^';
            --len;
            if(len <= 1)
                break;
            *d++ = 0x40 + *src;	/* turn it into a printable */
        } else
            *d++ = *src;
        ++src;
        --len;
    }
    *d = '\0';
    return dest;
}
