/*
 *  NeoIRCd: NeoStats Group. Based on Hybird7
 *  hook.c: Provides a generic event hooking interface.
 *
 *  Copyright (C) 2000-2002 Edward Brocklesby, Hybrid 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
 *
 *  $Id: hook.c,v 1.4 2002/09/14 03:58:49 fishwaldo Exp $
 */

/* hooks are used by modules to hook into events called by other parts of
   the code.  modules can also register their own events, and call them
   as appropriate. */

#include "stdinc.h"

#include "tools.h"
#include "list.h"
#include "hook.h"
#include "memory.h"

dlink_list hooks;

static hook *
find_hook(char *name);


void
init_hooks(void)
{
	memset(&hooks, 0, sizeof(hooks));
#ifndef NDEBUG
        hook_add_event("iosend");
        hook_add_event("iorecv");
        hook_add_event("iorecvctrl");
#endif
	hook_add_event("burst_channel");
	hook_add_event("svsalias");
}

static hook *
new_hook(char *name)
{
	hook *h;
	
	h = MyMalloc(sizeof(hook));
        DupString(h->name, name);
	return h;
}

int
hook_add_event(char *name)
{
	dlink_node *node;
	hook *newhook;

	/* if the hook already exists, then don't add it again. */
	if (find_hook(name)) return 0;

	node = make_dlink_node();
	newhook = new_hook(name);
	
	dlinkAdd(newhook, node, &hooks);
	return 0;
}

int
hook_del_event(char *name)
{
	dlink_node *node;
	hook *h;
	
	for (node = hooks.head; node; node = node->next)
	{
		h = node->data;
		
		if (!strcmp(h->name, name)) {
			dlinkDelete(node, &hooks);
			MyFree(h);
			return 0;
		}
	}
	return 0;
}

static hook *
find_hook(char *name)
{
	dlink_node *node;
	hook *h;
	
	for (node = hooks.head; node; node = node->next)
	{
		h = node->data;
		
		if (!strcmp(h->name, name))
			return h;
	}
	return NULL;
}

int 
hook_del_hook(char *event, hookfn *fn)
{
 hook *h;
 dlink_node *node, *nnode;
 h = find_hook(event);
 if (!h)
  return -1;
   
 for (node = h->hooks.head; node; node = nnode)
 {
  nnode = node->next;
  if (fn == node->data)
  {
   dlinkDelete(node, &h->hooks);
   free_dlink_node(node);
  } 
 }
 return 0;
}

int
hook_add_hook(char *event, hookfn *fn)
{
	hook *h;
	dlink_node *node;
	
	h = find_hook(event);
	if (!h) {
		hook_add_event(event);
		h = find_hook(event);
	}
	if (!h) {
		return -1;
	}
	node = make_dlink_node();
	
	dlinkAdd(fn, node, &h->hooks);
	return 0;
}

int
hook_call_event(char *event, void *data)
{
	hook *h;
	dlink_node *node;
	hookfn fn;
	
	h = find_hook(event);
	if (!h)
		return -1;
	for (node = h->hooks.head; node; node = node->next)
	{
		fn = (hookfn)(uintptr_t)node->data;
		if (fn(data) != 0)
			return 0;
	}
	return 0;
}