/*
* $Id: ft_routing.c,v 1.4 2004/09/04 21:46:24 hexwab Exp $
 *
 * Copyright (C) 2004 giFT project (gift.sourceforge.net)
 *
 * 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.
 */

#include "ft_openft.h"
#include "ft_bloom.h"
#include "ft_netorg.h"
#include "ft_routing.h"

SyncFilter md5_filter = { NULL, NULL };

static timer_id sync_timer;

static BOOL sync_filters (SyncFilter *f);

BOOL ft_routing_init (void)
{
	md5_filter.filter = ft_bloom_new (MD5_FILTER_BITS, MD5_FILTER_HASHES,
				    16 << 3, TRUE);

	if (!md5_filter.filter)
		return FALSE;

	md5_filter.sync = ft_bloom_clone (md5_filter.filter);

	if (!md5_filter.sync)
		return FALSE;

	sync_timer = timer_add (FILTER_SYNC_INTERVAL,
				(TimerCallback)sync_filters, &md5_filter);

	if (!sync_timer)
		return FALSE;

	return TRUE;
}

BOOL ft_routing_free (void)
{
	timer_remove (sync_timer);
  
	ft_bloom_free (md5_filter.filter);
	ft_bloom_free (md5_filter.sync);

	return TRUE;
}

static BOOL sync_filter (FTNode *node, FTPacket *pkt)
{
	/* TODO */
	return FALSE;
}

/* Sends updated routing information to all peers. */
static BOOL sync_filters (SyncFilter *f)
{
	FTPacket *pkt;

	if (!(pkt = ft_packet_new (FT_FILTER_SYNC, 0)))
		return FALSE;

	ft_bloom_diff (f->filter, f->sync);

	if (!ft_bloom_empty (f->sync))
	{
		int n;

		ft_packet_put_ustr (pkt, f->sync->table, 1 << (f->sync->bits-3));
		
		n = ft_netorg_foreach (FT_NODE_SEARCH, FT_NODE_CONNECTED, 0,
                           FT_NETORG_FOREACH(sync_filter), pkt);

		FT->DBGFN (FT, "sent routing update to %d peers (density %f)",
			   n, ft_bloom_density (f->sync));
	}

	ft_bloom_free (f->sync);
	
	f->sync = ft_bloom_clone (f->filter);

	ft_packet_free (pkt);

	return TRUE;
}