/*
 * ctcp.c:handles the client-to-client protocol(ctcp). 
 *
 * Written By Michael Sandrof 
 * Copyright(c) 1990, 1995 Michael Sandroff and others
 * See the COPYRIGHT file, or do a HELP IRCII COPYRIGHT 
 *
 * Serious cleanup by jfn (August 1996)
 */

#if 0
static	char	rcsid[] = "@(#)$Id: ctcp.c,v 1.16 1994/07/23 15:07:27 mrg Exp $";
#endif

#include "irc.h"
#include "irc_std.h"

#include <pwd.h>

#ifdef HAVE_UNAME
# include <sys/utsname.h>
#endif

#ifdef HAVE_STDARG_H
#include <stdarg.h>
#endif

#include "crypt.h"
#include "ctcp.h"
#include "dcc.h"
#include "edit.h"
#include "hook.h"
#include "ignore.h"
#include "ircaux.h"
#include "lastlog.h"
#include "names.h"
#include "output.h"
#include "parse.h"
#include "server.h"
#include "status.h"
#include "vars.h"
#include "window.h"
#include "if.h"

#define CTCP_SPECIAL	0	/* Limited, quiet, noreply, not expanded */
#define CTCP_REPLY	1	/* Sends a reply (not significant) */
#define CTCP_INLINE	2	/* Expands to an inline value */
#define CTCP_NOLIMIT	4	/* Limit of one per privmsg. */
#define CTCP_TELLUSER	8	/* Tell the user about it. */

static	void 	split_CTCP _((char *, char *, char *));

/*
 * ctcp_entry: the format for each ctcp function.   note that the function
 * described takes 4 parameters, a pointer to the ctcp entry, who the message
 * was from, who the message was to (nickname, channel, etc), and the rest of
 * the ctcp message.  it can return null, or it can return a malloced string
 * that will be inserted into the oringal message at the point of the ctcp.
 * if null is returned, nothing is added to the original message
 */

struct _CtcpEntry;
typedef char *(*CTCP_Handler) _((struct _CtcpEntry *, char *, char *, char *));
typedef	struct _CtcpEntry
{
	char		*name;  /* name of ctcp datatag */
	int		id;	/* index of this ctcp command */
	int		flag;	/* Action modifiers */
	char		*desc;  /* description returned by ctcp clientinfo */
	CTCP_Handler 	func;	/* function that does the dirty deed */
	CTCP_Handler 	repl;	/* Function that is called for reply */
}	CtcpEntry;

/* forward declarations for the built in CTCP functions */
static	char	*do_sed 	_((CtcpEntry *, char *, char *, char *));
static	char	*do_version 	_((CtcpEntry *, char *, char *, char *));
static	char	*do_clientinfo 	_((CtcpEntry *, char *, char *, char *));
static	char	*do_ping 	_((CtcpEntry *, char *, char *, char *));
static	char	*do_echo 	_((CtcpEntry *, char *, char *, char *));
static	char	*do_userinfo 	_((CtcpEntry *, char *, char *, char *));
static	char	*do_finger 	_((CtcpEntry *, char *, char *, char *));
static	char	*do_time 	_((CtcpEntry *, char *, char *, char *));
static	char	*do_atmosphere 	_((CtcpEntry *, char *, char *, char *));
static	char	*do_dcc 	_((CtcpEntry *, char *, char *, char *));
static	char	*do_utc 	_((CtcpEntry *, char *, char *, char *));
static	char	*do_dcc_reply 	_((CtcpEntry *, char *, char *, char *));
static	char	*do_ping_reply 	_((CtcpEntry *, char *, char *, char *));


static CtcpEntry ctcp_cmd[] =
{
	{ "SED",	CTCP_SED, 	CTCP_INLINE | CTCP_NOLIMIT,
		"contains simple_encrypted_data",
		do_sed, 	do_sed },
	{ "UTC",	CTCP_UTC, 	CTCP_INLINE | CTCP_NOLIMIT,
		"substitutes the local timezone",
		do_utc, 	do_utc },
	{ "ACTION",	CTCP_ACTION, 	CTCP_SPECIAL,
		"contains action descriptions for atmosphere",
		do_atmosphere, 	NULL },
	{ "DCC",	CTCP_DCC, 	CTCP_SPECIAL,
		"requests a direct_client_connection",
		do_dcc, 	do_dcc_reply },
	{ "VERSION",	CTCP_VERSION,	CTCP_REPLY | CTCP_TELLUSER,
		"shows client type, version and environment",
		do_version, 	NULL },
	{ "CLIENTINFO",	CTCP_CLIENTINFO,CTCP_REPLY | CTCP_TELLUSER,
		"gives information about available CTCP commands",
		do_clientinfo, 	NULL },
	{ "USERINFO",	CTCP_USERINFO, 	CTCP_REPLY | CTCP_TELLUSER,
		"returns user settable information",
		do_userinfo, 	NULL },
	{ "ERRMSG",	CTCP_ERRMSG, 	CTCP_REPLY | CTCP_TELLUSER,
		"returns error messages",
		do_echo, 	NULL },
	{ "FINGER",	CTCP_FINGER, 	CTCP_REPLY | CTCP_TELLUSER,
		"shows real name, login name and idle time of user", 
		do_finger, 	NULL },
	{ "TIME",	CTCP_TIME, 	CTCP_REPLY | CTCP_TELLUSER,
		"tells you the time on the user's host",
		do_time, 	NULL },
	{ "PING", 	CTCP_PING, 	CTCP_REPLY | CTCP_TELLUSER,
		"returns the arguments it receives",
		do_ping, 	do_ping_reply },
	{ "ECHO", 	CTCP_ECHO, 	CTCP_REPLY | CTCP_TELLUSER,
		"returns the arguments it receives",
		do_echo, 	NULL },
	{ NULL,		CTCP_CUSTOM,	CTCP_REPLY | CTCP_TELLUSER,
		NULL,
		NULL, NULL }
};

static char	*ctcp_type[] =
{
	"PRIVMSG",
	"NOTICE"
};

/* This is set to one if we parsed an SED */
int     sed = 0;

/*
 * in_ctcp_flag is set to true when IRCII is handling a CTCP request.  This
 * is used by the ctcp() sending function to force NOTICEs to be used in any
 * CTCP REPLY 
 */
int	in_ctcp_flag = 0;

#ifdef __STDC__
#define CTCP_HANDLER(x) \
	static char * x (CtcpEntry *ctcp, char *from, char *to, char *cmd)
#else
#define CTCP_HANDLER(x) 			\
	static char *x (ctcp, from, to, cmd)	\
	CtcpEntry   *ctcp;			\
	char	    *from, *to, *cmd;
#endif



/**************************** CTCP PARSERS ****************************/

/********** INLINE EXPANSION CTCPS ***************/
/*
 * do_sed: Performs the Simple Encrypted Data trasfer for ctcp.  Returns in a
 * malloc string the decryped message (if a key is set for that user) or the
 * text "[ENCRYPTED MESSAGE]" 
 */
CTCP_HANDLER(do_sed)
{
	char	*key = NULL,
		*crypt_who;
	char	*ret = NULL, *ret2 = NULL;

	if (my_stricmp(to, get_server_nickname(from_server)))
		crypt_who = to;
	else
		crypt_who = from;

	if ((key = is_crypted(crypt_who)))
		ret = decrypt_msg(cmd, key);

	if (!key || !ret)
		malloc_strcpy(&ret2, "[ENCRYPTED MESSAGE]");
	else
	{
		/* 
		 * There might be a CTCP message in there,
		 * so we see if we can find it.
		 */
		ret2 = m_strdup(do_ctcp(from, to, ret));
		sed = 1;
	}

	new_free(&ret);
	return ret2;
}

CTCP_HANDLER(do_utc)
{
	if (!cmd || !*cmd)
		return m_strdup(empty_string);

	return m_strdup(my_ctime(atol(cmd)));
}


/*
 * do_atmosphere: does the CTCP ACTION command --- done by lynX
 * Changed this to make the default look less offensive to people
 * who don't like it and added a /on ACTION. This is more in keeping
 * with the design philosophy behind IRCII
 */
CTCP_HANDLER(do_atmosphere)
{
	int old;

	if (!cmd || !*cmd)
		return NULL;

	old = set_lastlog_msg_level(LOG_ACTION);
	if (is_channel(to))
	{
		message_from(to, LOG_ACTION);
		if (do_hook(ACTION_LIST, "%s %s %s", from, to, cmd))
		{
			if (is_current_channel(to, 0))
				put_it("* %s %s", from, cmd);
			else
				put_it("* %s:%s %s", from, to, cmd);
		}
	}
	else
	{
		message_from(from, LOG_ACTION);
		if (do_hook(ACTION_LIST, "%s %s %s", from, to, cmd))
			put_it("*> %s %s", from, cmd);
	}

	message_from(NULL, LOG_CRAP);
	set_lastlog_msg_level(old);
	return NULL;
}

/*
 * do_dcc: Records data on an incoming DCC offer. Makes sure it's a
 *	user->user CTCP, as channel DCCs don't make any sense whatsoever
 */
CTCP_HANDLER(do_dcc)
{
	char	*type;
	char	*description;
	char	*inetaddr;
	char	*port;
	char	*size;
	char	*extra_flags;

	if (my_stricmp(to, get_server_nickname(from_server)))
		return NULL;

	if     (!(type = next_arg(cmd, &cmd)) ||
		!(description = next_arg(cmd, &cmd)) ||
		!(inetaddr = next_arg(cmd, &cmd)) ||
		!(port = next_arg(cmd, &cmd)))
			return NULL;

	size = next_arg(cmd, &cmd);
	extra_flags = next_arg(cmd, &cmd);

	register_dcc_offer(from, type, description, inetaddr, port, size, extra_flags);
	return NULL;
}



/*************** REPLY-GENERATING CTCPS *****************/

/*
 * do_clientinfo: performs the CLIENTINFO CTCP.  If cmd is empty, returns the
 * list of all CTCPs currently recognized by IRCII.  If an arg is supplied,
 * it returns specific information on that CTCP.  If a matching CTCP is not
 * found, an ERRMSG ctcp is returned 
 */
CTCP_HANDLER(do_clientinfo)
{
	int	i;

	if (cmd && *cmd)
	{
		for (i = 0; i < NUMBER_OF_CTCPS; i++)
		{
			if (my_stricmp(cmd, ctcp_cmd[i].name) == 0)
			{
				send_ctcp(CTCP_NOTICE, from, CTCP_CLIENTINFO, 
					"%s %s", 
					ctcp_cmd[i].name, ctcp_cmd[i].desc);
				return NULL;
			}
		}
		send_ctcp(CTCP_NOTICE, from, CTCP_ERRMSG,
				"%s: %s is not a valid function",
				ctcp_cmd[CTCP_CLIENTINFO].name, cmd);
	}
	else
	{
		char buffer[BIG_BUFFER_SIZE + 1];
		*buffer = '\0';

		for (i = 0; i < NUMBER_OF_CTCPS; i++)
		{
			strmcat(buffer, ctcp_cmd[i].name, BIG_BUFFER_SIZE);
			strmcat(buffer, " ", BIG_BUFFER_SIZE);
		}
		send_ctcp(CTCP_NOTICE, from, CTCP_CLIENTINFO,
			"%s :Use CLIENTINFO <COMMAND> to get more specific information", 
			buffer);
	}
	return NULL;
}

/* do_version: does the CTCP VERSION command */
CTCP_HANDLER(do_version)
{
	char	*tmp;

	/*
	 * The old way seemed lame to me... let's show system name and
	 * release information as well.  This will surely help out
	 * experts/gurus answer newbie questions.  -- Jake [WinterHawk] Khuon
	 *
	 * For the paranoid, UNAME_HACK hides the gory details of your OS.
	 */
#if defined(HAVE_UNAME) && !defined(UNAME_HACK)
	struct utsname un;
	char	*the_unix,
		*the_version;

	if (uname(&un) < 0)
	{
		the_version = empty_string;
		the_unix = "unknown";
	}
	else
	{
		the_version = un.release;
		the_unix = un.sysname;
	}

	send_ctcp(CTCP_NOTICE, from, CTCP_VERSION, 
			"ircII %s %s %s - %s", 
			irc_version, the_unix, the_version,
#else
	send_ctcp(CTCP_NOTICE, from, CTCP_VERSION, 
			"ircII %s *IX - %s", 
			irc_version,
#endif
			(tmp = get_string_var(CLIENTINFO_VAR)) ? tmp : IRCII_COMMENT);

	return NULL;
}

/* do_time: does the CTCP TIME command --- done by Veggen */
CTCP_HANDLER(do_time)
{
	send_ctcp(CTCP_NOTICE, from, CTCP_TIME, 
			"%s", my_ctime(time(NULL)));
	return NULL;
}

/* do_userinfo: does the CTCP USERINFO command */
CTCP_HANDLER(do_userinfo)
{
	send_ctcp(CTCP_NOTICE, from, CTCP_USERINFO,
			"%s", get_string_var(USERINFO_VAR));
	return NULL;
}

/*
 * do_echo: does the CTCP ECHO command. Does not send an error if the
 * CTCP was sent to a channel.
 */
CTCP_HANDLER(do_echo)
{
	if (!is_channel(to))
		send_ctcp(CTCP_NOTICE, from, CTCP_ECHO, "%s", cmd);
	return NULL;
}

CTCP_HANDLER(do_ping)
{
	send_ctcp(CTCP_NOTICE, from, CTCP_PING, "%s", cmd ? cmd : empty_string);
	return NULL;
}


/* 
 * Does the CTCP FINGER reply 
 */
CTCP_HANDLER(do_finger)
{
	struct	passwd	*pwd;
	time_t	diff;
	char	*tmp;
	char	*ctcpuser,
		*ctcpfinger;

	diff = time(NULL) - idle_time;

	if (!(pwd = getpwuid(getuid())))
		return NULL;

#ifndef GECOS_DELIMITER
#define GECOS_DELIMITER ','
#endif

	if ((tmp = index(pwd->pw_gecos, GECOS_DELIMITER)) != NULL)
		*tmp = '\0';

/* 
 * Three options for handling CTCP replies
 *  + Fascist Bastard Way -- normal, non-hackable fashion
 *  + Winterhawk way (default) -- allows hacking through IRCUSER and
 *	IRCFINGER environment variables
 *  + hop way -- returns a blank always
 */
#if defined(HOP)
	send_ctcp(CTCP_NOTICE, from, CTCP_FINGER, empty_string);
#else
# if !defined(I_DONT_TRUST_MY_USERS)
	/* 
	 * It would be pretty pointless to allow for customisable
	 * usernames if they can track via IRCNAME from the
	 * /etc/passwd file...  We therefore need to either disable
	 * CTCP_FINGER or also make it customisable.  Let's do the
	 * latter because it invokes less suspicion in the long run
	 *				-- Jake [WinterHawk] Khuon
	 */
	if ((ctcpuser = getenv("IRCUSER"))) 
		strmcpy(pwd->pw_name, ctcpuser, NAME_LEN);
	if ((ctcpfinger = getenv("IRCFINGER"))) 
		strmcpy(pwd->pw_gecos, ctcpfinger, NAME_LEN);
# endif
	send_ctcp(CTCP_NOTICE, from, CTCP_FINGER, 
		"%s (%s@%s) Idle %ld second%s", 
		pwd->pw_gecos, pwd->pw_name, hostname, diff, plural(diff));
#endif
	return NULL;
}


/* 
 * If we recieve a CTCP DCC REJECT in a notice, then we want to remove
 * the offending DCC request
 */
CTCP_HANDLER(do_dcc_reply)
{
	char *subcmd = NULL;
	char *type = NULL;

	if (is_channel(to))
		return NULL;

	if (cmd && *cmd)
		subcmd = next_arg(cmd, &cmd);
	if (cmd && *cmd)
		type = next_arg(cmd, &cmd);

	if (subcmd && type && !strcmp(subcmd, "REJECT"))
		dcc_reject (from, type, cmd);

	return NULL;
}


/*
 * Handles CTCP PING replies.
 */
CTCP_HANDLER(do_ping_reply)
{
	char *sec, *usec = NULL;
	struct timeval t;
	time_t tsec = 0, tusec = 0;

	if (!cmd || !*cmd)
		return NULL;		/* This is a fake -- cant happen. */

	gettimeofday(&t, NULL);

	/* We've already checked 'cmd' here, so its safe. */
	sec = cmd;
	tsec = t.tv_sec - atoi(sec);

	if ((usec = index(sec, ' ')))
	{
		*usec++ = 0;
		tusec = t.tv_usec - atoi(usec);
	}

	/*
	 * 'cmd', a variable passed in from do_notice_ctcp()
	 * points to a buffer which is MUCH larger than the
	 * string 'cmd' points at.  So this is safe, even
	 * if it looks "unsafe".
	 */
	sprintf(cmd, "%f seconds", (float)(tsec + (tusec / 1000000.0)));
	return NULL;
}


/************************************************************************/
/*
 * do_ctcp: a re-entrant form of a CTCP parser.  The old one was lame,
 * so i took a hatchet to it so it didnt suck.
 *
 * XXXX - important!  The third argument -- 'str', is expected to be
 * 'BIG_BUFFER_SIZE + 1' or larger.  If it isnt, chaos will probably 
 * ensue if you get spammed with lots of CTCP UTC requests.
 *
 * UTC requests can be at minimum 5 bytes, and the expansion is always 24.
 * That means you can cram (510 - strlen("PRIVMSG x :") / 5) UTCs (100)
 * into a privmsg.  That means itll expand to 2400 characters.  We silently
 * limit the number of valid CTCPs to 4.  Anything more than that we dont
 * even bother with. (4 * 24 + 11 -> 106), which is less than
 * IRCD_BUFFER_SIZE, which gives us plenty of safety.
 *
 * XXXX - The normal way of implementation required two copies -- once into a
 * temporary buffer, once back into the original buffer -- for the best case
 * scenario.  This is horrendously inefficient, since most privmsgs dont
 * contain any CTCPs.  So we check to see if there are any CTCPs in the
 * message before we bother doing anything.  THIS IS AN INELEGANT HACK!
 * But the call to word_count() is less expensive than even one copy to 
 * strcpy() since they both evaluate *each* character, and word_count()
 * doesnt have to do a write unless the character is present.  So it is 
 * definitely worth the cost to save CPU time for 99% of the PRIVMSGs.
 */
#ifdef __STDC__
extern 	char *do_ctcp (char *from, char *to, char *str)
#else
extern	char *do_ctcp (from, to, str)
	char *from, *to, *str;
#endif
{
	int 	flag;
	int	lastlog_level;
	char 	local_ctcp_buffer [BIG_BUFFER_SIZE + 1],
		the_ctcp          [IRCD_BUFFER_SIZE + 1],
		last              [IRCD_BUFFER_SIZE + 1];
	char	*ctcp_command,
		*ctcp_argument;
	int	i;
	char	*ptr = NULL;
	int	allow_ctcp_reply = 1;
static	time_t	last_ctcp_parsed = 0;

	int delim_char = charcount(str, CTCP_DELIM_CHAR);

	if (delim_char < 2)
		return str;		/* No CTCPs. */
	if (delim_char > 8)
		allow_ctcp_reply = 0;	/* Historical limit of 4 CTCPs */

	flag = check_ignore_channel(from, FromUserHost, to, IGNORE_CTCPS);
	if (!in_ctcp_flag)
		in_ctcp_flag = 1;
	strmcpy(local_ctcp_buffer, str, IRCD_BUFFER_SIZE);

	for (;;strmcat(local_ctcp_buffer, last, BIG_BUFFER_SIZE))
	{
		split_CTCP(local_ctcp_buffer, the_ctcp, last);

		if (!*the_ctcp)
			break;		/* all done! */

		/*
		 * Apply some integrety rules:
		 * -- If we've already replied to a CTCP, ignore it.
		 * -- If user is ignoring sender, ignore it.
		 * -- If we're being flooded, ignore it.
		 * -- If CTCP was a global msg, ignore it.
		 */

		/*
		 * Yes, this intentionally ignores "unlimited" CTCPs like
		 * UTC and SED.  Ultimately, we have to make sure that
		 * CTCP expansions dont overrun any buffers that might
		 * contain this string down the road.  So by allowing up to
		 * 4 CTCPs, we know we cant overflow -- but if we have more
		 * than 40, it might overflow, and its probably a spam, so
		 * no need to shed tears over ignoring them.  Also makes
		 * the sanity checking much simpler.
		 */
		if (!allow_ctcp_reply)
			continue;

		/*
		 * Check to see if the user is ignoring person.
		 */
		if (flag == IGNORED)
		{
			if (x_debug)
				yell("CTCP from [%s] ignored", from);

			allow_ctcp_reply = 0;
			continue;
		}

		/*
		 * Check for CTCP flooding
		 */
		if (get_int_var(NO_CTCP_FLOOD_VAR))
		{
			if (time(NULL) - last_ctcp_parsed < 2)
			{
				/*
				 * This extends the flood protection until
				 * we dont get a CTCP for 2 seconds.
				 */
				last_ctcp_parsed = time(NULL);
				allow_ctcp_reply = 0;
				if (x_debug)
					say("CTCP flood from [%s] ignored", from);
				continue;
			}
		}

		/*
		 * Check for global message
		 */
		if (*to == '$' || (*to == '#' && !lookup_channel(to, from_server, 0)))
		{
			allow_ctcp_reply = 0;
			continue;
		}


		/*
		 * Now its ok to parse the CTCP.  
		 * First we remove the argument.
		 */
		ctcp_command = the_ctcp;
		ctcp_argument = index(the_ctcp, ' ');
		if (ctcp_argument)
			*ctcp_argument++ = 0;
		else
			ctcp_argument = empty_string;


		/*
		 * Then we look for the correct CTCP.
		 */
		for (i = 0; i < NUMBER_OF_CTCPS; i++)
			if (!strcmp(ctcp_command, ctcp_cmd[i].name))
				break;

		/*
		 * We didnt find it?
		 */
		if (i == NUMBER_OF_CTCPS)
		{
			/*
			 * Offer it to the user.
			 * Maybe they know what to do with it.
			 */
			if (do_hook(CTCP_LIST, "%s %s %s %s", from, to, ctcp_command, ctcp_argument))
			{
				if (get_int_var(VERBOSE_CTCP_VAR))
					say("Unknown CTCP %s from %s to %s: %s%s",
						ctcp_command, from, to, *ctcp_argument ? ": " :
						empty_string, ctcp_argument);
			}
			time(&last_ctcp_parsed);
			allow_ctcp_reply = 0;
			continue;
		}

		/* 
		 * We did find it.  Acknowledge it.
		 */
		ptr = ctcp_cmd[i].func(ctcp_cmd + i, from, to, ctcp_argument);

		/*
		 * If this isnt an 'unlimited' CTCP, set up flood protection.
		 *
		 * No, this wont allow users to flood any more than they
		 * would normally.  The UTC/SED gets converted into a 
		 * regular privmsg body, which is flagged via FLOOD_PUBLIC.
		 */
		if (!(ctcp_cmd[i].flag & CTCP_NOLIMIT))
		{
			time(&last_ctcp_parsed);
			allow_ctcp_reply = 0;
		}


		/*
		 * We've only gotten to this point if its a valid CTCP
		 * query and we decided to parse it.
		 */

		/*
		 * If its an ``INLINE'' CTCP, we paste it back in.
		 */
		if (ctcp_cmd[i].flag & CTCP_INLINE)
			strmcat(local_ctcp_buffer, ptr, BIG_BUFFER_SIZE);

		/* 
		 * If its ``INTERESTING'', tell the user.
		 * Note that this isnt mutex with ``INLINE'' in theory,
		 * even though it is in practice.  Dont use 'else' here.
		 */
		if (ctcp_cmd[i].flag & CTCP_TELLUSER)
		{
			if (do_hook(CTCP_LIST, "%s %s %s %s", from, to, ctcp_command, ctcp_argument))
			{
				/* Set up the window level/logging */
				lastlog_level = set_lastlog_msg_level(LOG_CTCP);
				message_from(NULL, LOG_CTCP);

				if (get_int_var(VERBOSE_CTCP_VAR))
				if (!my_stricmp(to, get_server_nickname(from_server)))
					say("CTCP %s from %s%s%s", 
						ctcp_command, from, 
						ctcp_argument && *ctcp_argument ? ": " : empty_string, 
						ctcp_argument && *ctcp_argument ? ctcp_argument : empty_string);
				else
					say("CTCP %s from %s to %s%s%s",
						ctcp_command, from, to, 
						ctcp_argument && *ctcp_argument ? ": " : empty_string, 
						ctcp_argument && *ctcp_argument ? ctcp_argument : empty_string);

				/* Reset the window level/logging */
				set_lastlog_msg_level(lastlog_level);
			}
		}

		new_free(&ptr);
	}

	if (in_ctcp_flag == 1)
		in_ctcp_flag = 0;

	return strcpy(str, local_ctcp_buffer);
}



/*
 * do_notice_ctcp: a re-entrant form of a CTCP reply parser.
 * See the implementation notes in do_ctcp().
 */
#ifdef __STDC__
extern 	char *do_notice_ctcp (char *from, char *to, char *str)
#else
extern	char *do_notice_ctcp (from, to, str)
	char *from, *to, *str;
#endif
{
	int 	flag;
	int	lastlog_level;
	char 	local_ctcp_buffer [BIG_BUFFER_SIZE + 1],
		the_ctcp          [IRCD_BUFFER_SIZE + 1],
		last              [IRCD_BUFFER_SIZE + 1];
	char	*ctcp_command,
		*ctcp_argument;
	int	i;
	char	*ptr;
	int	allow_ctcp_reply = 1;

	int delim_char = charcount(str, CTCP_DELIM_CHAR);

	if (delim_char < 2)
		return str;		/* No CTCPs. */
	if (delim_char > 8)
		allow_ctcp_reply = 0;	/* Ignore all the CTCPs. */

	flag = check_ignore_channel(from, FromUserHost, to, IGNORE_CTCPS);
	if (!in_ctcp_flag)
		in_ctcp_flag = -1;
	strmcpy(local_ctcp_buffer, str, IRCD_BUFFER_SIZE);

	for (;;strmcat(local_ctcp_buffer, last, BIG_BUFFER_SIZE))
	{
		split_CTCP(local_ctcp_buffer, the_ctcp, last);
		if (!*the_ctcp)
			break;		/* all done! */

		/*
		 * Apply sanity rules
		 */

		if (!allow_ctcp_reply)
			continue;

		if (flag == IGNORED)
		{
			if (x_debug)
				yell("CTCP REPLY from [%s] ignored", from);
			allow_ctcp_reply = 0;
			continue;
		}

		/* Global messages -- just drop the CTCP */
		if (*to == '$' || (*to == '#' && !lookup_channel(to, from_server, 0)))
		{
			allow_ctcp_reply = 0;
			continue;
		}


		/*
		 * Parse CTCP message
		 */

		ctcp_command = the_ctcp;
		ctcp_argument = index(the_ctcp, ' ');
		if (ctcp_argument)
			*ctcp_argument++ = 0;
		else
			ctcp_argument = empty_string;


		/* 
		 * Find the correct CTCP and run it.
		 */

		for (i = 0; i < NUMBER_OF_CTCPS; i++)
			if (!strcmp(ctcp_command, ctcp_cmd[i].name))
				break;

		/* 
		 * If its a built in CTCP command, check to see if its
		 * got a reply handler, call if appropriate.
		 */
		if (i < NUMBER_OF_CTCPS && ctcp_cmd[i].repl)
		{
			if ((ptr = ctcp_cmd[i].repl(ctcp_cmd + i, from, to, ctcp_argument)))
			{
				strmcat(local_ctcp_buffer, ptr, BIG_BUFFER_SIZE);
				new_free(&ptr);
				continue;
			}
		}

		/* Toss it at the user.  */
		if (do_hook(CTCP_REPLY_LIST, "%s %s %s", from, ctcp_command, ctcp_argument))
		{
			/* Set up the window level/logging */
			lastlog_level = set_lastlog_msg_level(LOG_CTCP);
			message_from(NULL, LOG_CTCP);

			say("CTCP %s reply from %s: %s", ctcp_command, from, ctcp_argument);

			/* Reset the window level/logging */
			set_lastlog_msg_level(lastlog_level);
		}

		if (!(ctcp_cmd[i].flag & CTCP_NOLIMIT))
			allow_ctcp_reply = 0;
	}

	if (in_ctcp_flag == -1)
		in_ctcp_flag = 0;

	return strcpy(str, local_ctcp_buffer);
}



/* in_ctcp: simply returns the value of the ctcp flag */
extern int	in_ctcp _((void)) { return (in_ctcp_flag); }



/*
 * This is no longer directly sends information to its target.
 * As part of a larger attempt to consolidate all data transmission
 * into send_text, this function was modified so as to use send_text().
 * This function can send both direct CTCP requests, as well as the
 * appropriate CTCP replies.  By its use of send_text(), it can send
 * CTCPs to DCC CHAT and irc nickname peers, and handles encryption
 * transparantly.  This greatly reduces the logic, complexity, and
 * possibility for error in this function.
 */
#if defined(__STDC__) && defined(HAVE_STDARG_H)
extern	void	send_ctcp(int type, char *to, int datatag, char *format, ...)
#else
extern	void	send_ctcp(type, to, datatag, format, arg0, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9)
	int	type, datatag;
	char 	*to, *format,
     		*arg0, *arg1, *arg2, *arg3, *arg4, 
		*arg5, *arg6, *arg7, *arg8, *arg9;
#endif
{
	char putbuf [BIG_BUFFER_SIZE + 1],
	     putbuf2[BIG_BUFFER_SIZE + 1];

	if (in_on_who)
		return;

	if (format)
	{
#if defined(__STDC__) && defined(HAVE_STDARG_H)
		va_list args;
		va_start(args, format);
		vsprintf(putbuf, format, args);
		va_end(args);
#else
		sprintf(putbuf, format, arg0, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9);
#endif

		sprintf(putbuf2, "%c%s %s%c", CTCP_DELIM_CHAR, ctcp_cmd[datatag].name, putbuf, CTCP_DELIM_CHAR);
	}
	else
		sprintf(putbuf2, "%c%s%c", CTCP_DELIM_CHAR, ctcp_cmd[datatag].name, CTCP_DELIM_CHAR);


	send_text(to, putbuf2, ctcp_type[type], 0);
}


/*
 * quote_it: This quotes the given string making it sendable via irc.  A
 * pointer to the length of the data is required and the data need not be
 * null terminated (it can contain nulls).  Returned is a malloced, null
 * terminated string.   
 */
#ifdef __STDC__
extern 	char	*ctcp_quote_it (char *str, int len)
#else
extern 	char	*ctcp_quote_it(str, len)
	char	*str;
	int	len;
#endif
{
	char	buffer[BIG_BUFFER_SIZE + 1];
	char	*ptr;
	int	i;

	ptr = buffer;
	for (i = 0; i < len; i++)
	{
		switch (str[i])
		{
			case CTCP_DELIM_CHAR:	*ptr++ = CTCP_QUOTE_CHAR;
						*ptr++ = 'a';
						break;
			case '\n':		*ptr++ = CTCP_QUOTE_CHAR;
						*ptr++ = 'n';
						break;
			case '\r':		*ptr++ = CTCP_QUOTE_CHAR;
						*ptr++ = 'r';
						break;
			case CTCP_QUOTE_CHAR:	*ptr++ = CTCP_QUOTE_CHAR;
						*ptr++ = CTCP_QUOTE_CHAR;
						break;
			case '\0':		*ptr++ = CTCP_QUOTE_CHAR;
						*ptr++ = '0';
						break;
			default:		*ptr++ = str[i];
						break;
		}
	}
	*ptr = '\0';
	return m_strdup(buffer);
}

/*
 * ctcp_unquote_it: This takes a null terminated string that had previously
 * been quoted using ctcp_quote_it and unquotes it.  Returned is a malloced
 * space pointing to the unquoted string.  NOTE: a trailing null is added for
 * convenied, but the returned data may contain nulls!.  The len is modified
 * to contain the size of the data returned. 
 */
#ifdef __STDC__
extern	char	*ctcp_unquote_it (char *str, int *len)
#else
extern	char	*ctcp_unquote_it(str, len)
	char	*str;
	int	*len;
#endif
{
	char	*buffer;
	char	*ptr;
	char	c;
	int	i,
		new_size = 0;

	buffer = (char *) new_malloc(sizeof(char) * *len);
	ptr = buffer;
	i = 0;
	while (i < *len)
	{
		if ((c = str[i++]) == CTCP_QUOTE_CHAR)
		{
			switch (c = str[i++])
			{
				case CTCP_QUOTE_CHAR:
					*ptr++ = CTCP_QUOTE_CHAR;
					break;
				case 'a':
					*ptr++ = CTCP_DELIM_CHAR;
					break;
				case 'n':
					*ptr++ = '\n';
					break;
				case 'r':
					*ptr++ = '\r';
					break;
				case '0':
					*ptr++ = '\0';
					break;
				default:
					*ptr++ = c;
					break;
			}
		}
		else
			*ptr++ = c;
		new_size++;
	}
	*ptr = '\0';
	*len = new_size;
	return (buffer);
}

#ifdef __STDC__
extern int get_ctcp_val (char *str)
#else
extern int get_ctcp_val (str)
char *str;
#endif
{
	int i;

	for (i = 0; i < NUMBER_OF_CTCPS; i++)
		if (!strcmp(str, ctcp_cmd[i].name))
			return i;

	/*
	 * This is *dangerous*, but it works.  The only place that
	 * calls this function is edit.c:ctcp(), and it immediately
	 * calls send_ctcp().  So the pointer that is being passed
	 * to us is globally allocated at a level higher then ctcp().
	 * so it wont be bogus until some time after ctcp() returns,
	 * but at that point, we dont care any more.
	 */
	ctcp_cmd[CTCP_CUSTOM].name = str;
	return CTCP_CUSTOM;
}



/*
 * XXXX -- some may call this a hack, but if youve got a better
 * way to handle this job, id love to use it.
 */
void split_CTCP(char *raw_message, char *ctcp_dest, char *after_ctcp)
{
	char *ctcp_start, *ctcp_end;

	*ctcp_dest = *after_ctcp = 0;
	ctcp_start = index(raw_message, CTCP_DELIM_CHAR);
	if (!ctcp_start)
		return;		/* No CTCPs present. */

	*ctcp_start++ = 0;
	ctcp_end = index(ctcp_start, CTCP_DELIM_CHAR);
	if (!ctcp_end)
	{
		*--ctcp_start = CTCP_DELIM_CHAR;
		return;		/* Thats _not_ a CTCP. */
	}

	*ctcp_end++ = 0;
	strmcpy(ctcp_dest, ctcp_start, IRCD_BUFFER_SIZE);
	strmcpy(after_ctcp, ctcp_end, IRCD_BUFFER_SIZE);

	return;		/* All done! */
}