/*******************************************************************************
 * libretroshare/src/tcponudp: udprelay.cc                                     *
 *                                                                             *
 * libretroshare: retroshare core library                                      *
 *                                                                             *
 * Copyright 2010-2010 by Robert Fernie <retroshare@lunamutt.com>              *
 *                                                                             *
 * This program is free software: you can redistribute it and/or modify        *
 * it under the terms of the GNU Lesser General Public License as              *
 * published by the Free Software Foundation, either version 3 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 Lesser General Public License for more details.                         *
 *                                                                             *
 * You should have received a copy of the GNU Lesser General Public License    *
 * along with this program. If not, see <https://www.gnu.org/licenses/>.       *
 *                                                                             *
 *******************************************************************************/
#include "udprelay.h"
#include <iostream>
#include "util/rstime.h"
#include <util/rsmemory.h>

/*
 * #define DEBUG_UDP_RELAY 		1
 * #define DEBUG_UDP_RELAY_PKTS		1
 * #define DEBUG_UDP_RELAY_ERRORS	1
 */

#define DEBUG_UDP_RELAY_ERRORS	1

#ifdef DEBUG_UDP_RELAY
// DEBUG FUNCTION
#include "util/rsstring.h"
#include <iomanip>
int displayUdpRelayPacketHeader(const void *data, const int size);
#endif

/****************** UDP RELAY STUFF **********/

// This packet size must be able to handle TcpStream Packets.
// At the moment, they can be 1000 + 20 for TcpOnUdp ... + 16 => 1036 minimal size.
// See Notes in tcpstream.h for more info
#define MAX_RELAY_UDP_PACKET_SIZE (1400 + 20 + 16)


UdpRelayReceiver::UdpRelayReceiver(UdpPublisher *pub)
	:UdpSubReceiver(pub), udppeerMtx("UdpSubReceiver"), relayMtx("UdpSubReceiver")
{
	mClassLimit.resize(UDP_RELAY_NUM_CLASS);
	mClassCount.resize(UDP_RELAY_NUM_CLASS);
	mClassBandwidth.resize(UDP_RELAY_NUM_CLASS);


	for(int i = 0; i < UDP_RELAY_NUM_CLASS; i++)
	{
		mClassCount[i] = 0;
		mClassBandwidth[i] = 0;
	}

	setRelayTotal(UDP_RELAY_DEFAULT_COUNT_ALL);
	setRelayClassMax(UDP_RELAY_CLASS_FRIENDS, UDP_RELAY_DEFAULT_FRIEND, UDP_RELAY_DEFAULT_BANDWIDTH);
	setRelayClassMax(UDP_RELAY_CLASS_FOF,     UDP_RELAY_DEFAULT_FOF, UDP_RELAY_DEFAULT_BANDWIDTH);
	setRelayClassMax(UDP_RELAY_CLASS_GENERAL, UDP_RELAY_DEFAULT_GENERAL, UDP_RELAY_DEFAULT_BANDWIDTH);

	/* only allocate this space once */
	mTmpSendPkt = rs_malloc(MAX_RELAY_UDP_PACKET_SIZE);
	mTmpSendSize = MAX_RELAY_UDP_PACKET_SIZE;

	clearDataTransferred();

	return;
}

UdpRelayReceiver::~UdpRelayReceiver()
{
	free(mTmpSendPkt);
}


int     UdpRelayReceiver::addUdpPeer(UdpPeer *peer, UdpRelayAddrSet *endPoints, const struct sockaddr_in *proxyaddr)
{
	struct sockaddr_in realPeerAddr = endPoints->mDestAddr;
	{
		RsStackMutex stack(relayMtx);   /********** LOCK MUTEX *********/
		
		/* check for duplicate */
		std::map<struct sockaddr_in, UdpRelayEnd>::iterator it;
		it = mStreams.find(realPeerAddr);
		bool ok = (it == mStreams.end());
		if (!ok)
		{
#ifdef DEBUG_UDP_RELAY_ERRORS
			std::cerr << "UdpRelayReceiver::addUdpPeer() ERROR Peer already exists!" << std::endl;
#endif
			return 0;
		}
		
		/* setup a peer */
		UdpRelayEnd ure(endPoints, proxyaddr);

#ifdef DEBUG_UDP_RELAY
		std::cerr << "UdpRelayReceiver::addUdpPeer() Installing UdpRelayEnd: " << ure << std::endl;
#endif

		mStreams[realPeerAddr] = ure;
	}
		
	{
		RsStackMutex stack(udppeerMtx);   /********** LOCK MUTEX *********/
		

#ifdef DEBUG_UDP_RELAY
		std::cerr << "UdpRelayReceiver::addUdpPeer() Installing UdpPeer" << std::endl;
#endif
		
		/* just overwrite */
		mPeers[realPeerAddr] = peer;

	}
		
	return 1;
}


int     UdpRelayReceiver::removeUdpPeer(UdpPeer *peer)
{
	bool found = false;
	struct sockaddr_in realPeerAddr;

	/* cleanup UdpPeer, and get reference for data */
	{
		RsStackMutex stack(udppeerMtx);   /********** LOCK MUTEX *********/
		
		std::map<struct sockaddr_in, UdpPeer *>::iterator it;
		for(it = mPeers.begin(); it != mPeers.end(); ++it)
		{
			if (it->second == peer)
			{
				realPeerAddr = it->first;
				mPeers.erase(it);
				found = true;

#ifdef DEBUG_UDP_RELAY
				std::cerr << "UdpRelayReceiver::removeUdpPeer() removing UdpPeer" << std::endl;
#endif
				break;
			}
		}
	}

	if (!found)
	{
#ifdef DEBUG_UDP_RELAY_ERRORS
		std::cerr << "UdpRelayReceiver::removeUdpPeer() Warning: Failed to find UdpPeer" << std::endl;
#endif
		return 0;
	}

	/* now we cleanup the associated data */
	{
		RsStackMutex stack(relayMtx);   /********** LOCK MUTEX *********/
		
		std::map<struct sockaddr_in, UdpRelayEnd>::iterator it;
		it = mStreams.find(realPeerAddr);
		if (it != mStreams.end())
		{
			mStreams.erase(it);
		}
		else
		{
			/* ERROR */	
#ifdef DEBUG_UDP_RELAY_ERRORS
			std::cerr << "UdpRelayReceiver::removeUdpPeer() ERROR failed to find Mapping" << std::endl;
#endif
		}
	}
	return 1;
}

int UdpRelayReceiver::getRelayEnds(std::list<UdpRelayEnd> &relayEnds)
{
        RsStackMutex stack(relayMtx);   /********** LOCK MUTEX *********/

	std::map<struct sockaddr_in, UdpRelayEnd>::iterator rit;
	
	for(rit = mStreams.begin(); rit != mStreams.end(); ++rit)
	{
		relayEnds.push_back(rit->second);
	}
	return 1;


}

int UdpRelayReceiver::getRelayProxies(std::list<UdpRelayProxy> &relayProxies)
{
        RsStackMutex stack(relayMtx);   /********** LOCK MUTEX *********/

	std::map<UdpRelayAddrSet, UdpRelayProxy>::iterator rit;
	
	for(rit = mRelays.begin(); rit != mRelays.end(); ++rit)
	{
		relayProxies.push_back(rit->second);
	}
	return 1;
}

#define RELAY_MAX_BANDWIDTH 1000
#define RELAY_TIMEOUT		30


int UdpRelayReceiver::checkRelays()
{

#ifdef DEBUG_UDP_RELAY
	// As this locks - must be out of the Mutex.
	status(std::cerr);
#endif

        RsStackMutex stack(relayMtx);   /********** LOCK MUTEX *********/

	/* iterate through the Relays */

#ifdef DEBUG_UDP_RELAY
	std::cerr << "UdpRelayReceiver::checkRelays()";
	std::cerr << std::endl;
#endif

	std::list<UdpRelayAddrSet> eraseList;
	std::map<UdpRelayAddrSet, UdpRelayProxy>::iterator rit;
	rstime_t now = time(NULL);

#define BANDWIDTH_FILTER_K	(0.8)
	
	for(rit = mRelays.begin(); rit != mRelays.end(); ++rit)
	{
		/* calc bandwidth */
		//rit->second.mBandwidth = rit->second.mDataSize / (float) (now - rit->second.mLastBandwidthTS);
		// Switch to a Low-Pass Filter to average it out.
		float instantBandwidth = rit->second.mDataSize / (float) (now - rit->second.mLastBandwidthTS);
	
		rit->second.mBandwidth *= (BANDWIDTH_FILTER_K);
		rit->second.mBandwidth += (1.0 - BANDWIDTH_FILTER_K) * instantBandwidth;

		rit->second.mDataSize = 0;
		rit->second.mLastBandwidthTS = now;

#ifdef DEBUG_UDP_RELAY
		std::cerr << "UdpRelayReceiver::checkRelays()";
		std::cerr << "Relay: " << rit->first;
		std::cerr << " using bandwidth: " << rit->second.mBandwidth;
		std::cerr << std::endl;
#endif

		// ONLY A WARNING.
#ifdef DEBUG_UDP_RELAY
		if (instantBandwidth > rit->second.mBandwidthLimit)
		{
			std::cerr << "UdpRelayReceiver::checkRelays() ";
			std::cerr << "Warning instantBandwidth: " << instantBandwidth;
			std::cerr << " Exceeding Limit: " << rit->second.mBandwidthLimit;
			std::cerr << " for Relay: " << rit->first;
			std::cerr << std::endl;
		}
#endif

		if (rit->second.mBandwidth > rit->second.mBandwidthLimit)
		{
#ifdef DEBUG_UDP_RELAY_ERRORS
			std::cerr << "UdpRelayReceiver::checkRelays() ";
			std::cerr << "Dropping Relay due to excessive Bandwidth: " << rit->second.mBandwidth;
			std::cerr << " Exceeding Limit: " << rit->second.mBandwidthLimit;
			std::cerr << " Relay: " << rit->first;
			std::cerr << std::endl;
#endif

			/* if exceeding bandwidth -> drop */
			eraseList.push_back(rit->first);
		}
		else if (now - rit->second.mLastTS > RELAY_TIMEOUT)
		{
#ifdef DEBUG_UDP_RELAY_ERRORS
			/* if haven't transmitted for ages -> drop */
			std::cerr << "UdpRelayReceiver::checkRelays() ";
			std::cerr << "Dropping Relay due to Timeout: " << rit->first;
			std::cerr << std::endl;
#endif
			eraseList.push_back(rit->first);
		}
		else
		{
			/* check the length of the relay - we will drop them after a certain amount of time */
			int lifetime = 0;
			switch(rit->second.mRelayClass)
			{
				default:
			    case UDP_RELAY_CLASS_GENERAL:
					lifetime = UDP_RELAY_LIFETIME_GENERAL;
					break;
			    case UDP_RELAY_CLASS_FOF:
					lifetime = UDP_RELAY_LIFETIME_FOF;
					break;
			    case UDP_RELAY_CLASS_FRIENDS:
					lifetime = UDP_RELAY_LIFETIME_FRIENDS;
					break;
			}
			if (now - rit->second.mStartTS > lifetime)
			{
#ifdef DEBUG_UDP_RELAY
				std::cerr << "UdpRelayReceiver::checkRelays() ";
				std::cerr << "Dropping Relay due to Passing Lifetime Limit: " << lifetime;
				std::cerr << " for class: " << rit->second.mRelayClass;
				std::cerr << " Relay: " << rit->first;
				std::cerr << std::endl;
#endif

				eraseList.push_back(rit->first);
			}
		}
	}

	std::list<UdpRelayAddrSet>::iterator it;
	for(it = eraseList.begin(); it != eraseList.end(); ++it)
	{
		removeUdpRelay_relayLocked(&(*it));
	}

	return 1;
}


int UdpRelayReceiver::removeUdpRelay(UdpRelayAddrSet *addrSet)
{
	RsStackMutex stack(relayMtx);   /********** LOCK MUTEX *********/

#ifdef DEBUG_UDP_RELAY
	std::cerr << "UdpRelayReceiver::removeUdpRelay() :" << *addrSet << std::endl;
#endif

	return removeUdpRelay_relayLocked(addrSet);
}


int UdpRelayReceiver::addUdpRelay(UdpRelayAddrSet *addrSet, int &relayClass, uint32_t &bandwidth)
{
	RsStackMutex stack(relayMtx);   /********** LOCK MUTEX *********/

	/* check for duplicate */
	std::map<UdpRelayAddrSet, UdpRelayProxy>::iterator rit = mRelays.find(*addrSet);
	int ok = (rit == mRelays.end());
	if (!ok)
	{
#ifdef DEBUG_UDP_RELAY_ERRORS
		std::cerr << "UdpRelayReceiver::addUdpRelay() ERROR Peer already exists!" << std::endl;
#endif
		return 0;
	}

	/* will install if there is space! */
	if (installRelayClass_relayLocked(relayClass, bandwidth))
	{
#ifdef DEBUG_UDP_RELAY
		std::cerr << "UdpRelayReceiver::addUdpRelay() adding Relay" << std::endl;
#endif
		/* create UdpRelay */
		UdpRelayProxy udpRelay(addrSet, relayClass, bandwidth);
		UdpRelayAddrSet alt = addrSet->flippedSet();
		UdpRelayProxy altUdpRelay(&alt, relayClass, bandwidth);

		/* must install two (A, B) & (B, A) */
		mRelays[*addrSet] = udpRelay;
		mRelays[alt] = altUdpRelay;

		/* grab bandwidth from one set */
		bandwidth = altUdpRelay.mBandwidthLimit;

		return 1;
	}

#ifdef DEBUG_UDP_RELAY_ERRORS
	std::cerr << "UdpRelayReceiver::addUdpRelay() WARNING Too many Relays!" << std::endl;
#endif
	return 0;
}



int UdpRelayReceiver::removeUdpRelay_relayLocked(UdpRelayAddrSet *addrSet)
{
#ifdef DEBUG_UDP_RELAY
	std::cerr << "UdpRelayReceiver::removeUdpRelay_relayLocked() :" << *addrSet << std::endl;
#endif

	/* find in Relay list */
        std::map<UdpRelayAddrSet, UdpRelayProxy>::iterator rit = mRelays.find(*addrSet);
	if (rit == mRelays.end())
	{
		/* ERROR */
		std::cerr << "UdpRelayReceiver::removeUdpRelay()";
		std::cerr << "ERROR Finding Relay: " << *addrSet;
		std::cerr << std::endl;
	}
	else
	{
		/* lets drop the count here too */
		removeRelayClass_relayLocked(rit->second.mRelayClass);
		mRelays.erase(rit);
	}

	/* rotate around and delete matching set */
	UdpRelayAddrSet alt = addrSet->flippedSet();

	rit = mRelays.find(alt);
	if (rit == mRelays.end())
	{
		std::cerr << "UdpRelayReceiver::removeUdpRelay()";
		std::cerr << "ERROR Finding Alt Relay: " << alt;
		std::cerr << std::endl;
		/* ERROR */
	}
	else
	{
		mRelays.erase(rit);
	}
	return 1;
}

        /* Need some stats, to work out how many relays we are supporting 	
	 * modified the code to allow degrading of class ....
	 * so if you have too many friends, they will fill a FOF spot
	 */
int UdpRelayReceiver::installRelayClass_relayLocked(int &classIdx, uint32_t &bandwidth)
{
	/* check for total number of Relays */
	if (mClassCount[UDP_RELAY_CLASS_ALL] >= mClassLimit[UDP_RELAY_CLASS_ALL])
	{
		std::cerr << "UdpRelayReceiver::installRelayClass() WARNING Too many Relays already";
		std::cerr << std::endl;
		return 0;
	}

	/* check the idx too */
	if ((classIdx < 0) || (classIdx >= UDP_RELAY_NUM_CLASS))
	{
		std::cerr << "UdpRelayReceiver::installRelayClass() ERROR class Idx invalid";
		std::cerr << std::endl;
		return 0;
	}	

	/* now check the specifics of the class */
	while(mClassCount[classIdx] >= mClassLimit[classIdx])
	{
		std::cerr << "UdpRelayReceiver::installRelayClass() WARNING Relay Class Limit Exceeded";
		std::cerr << std::endl;
		std::cerr << "UdpRelayReceiver::installRelayClass() ClassIdx: " << classIdx;
		std::cerr << std::endl;
		std::cerr << "UdpRelayReceiver::installRelayClass() ClassLimit: " << mClassLimit[classIdx];
		std::cerr << std::endl;
		std::cerr << "UdpRelayReceiver::installRelayClass() Degrading Class =>: " << classIdx;
		std::cerr << std::endl;

		classIdx--;
		if (classIdx == 0)
		{
			std::cerr << "UdpRelayReceiver::installRelayClass() No Spaces Left";
			std::cerr << std::endl;

			return 0;
		}
	}

	std::cerr << "UdpRelayReceiver::installRelayClass() Relay Class Ok, Count incremented";
	std::cerr << std::endl;

	/* if we get here we can add one */
	++mClassCount[UDP_RELAY_CLASS_ALL];
	++mClassCount[classIdx];
	bandwidth = mClassBandwidth[classIdx];

	return 1;
}

int UdpRelayReceiver::removeRelayClass_relayLocked(int classIdx)
{
	/* check for total number of Relays */
	if (mClassCount[UDP_RELAY_CLASS_ALL] < 1)
	{
		std::cerr << "UdpRelayReceiver::removeRelayClass() ERROR no relays installed";
		std::cerr << std::endl;
		return 0;
	}

	/* check the idx too */
	if ((classIdx < 0) || (classIdx >= UDP_RELAY_NUM_CLASS))
	{
		std::cerr << "UdpRelayReceiver::removeRelayClass() ERROR class Idx invalid";
		std::cerr << std::endl;
		return 0;
	}	

	/* now check the specifics of the class */
	if (mClassCount[classIdx] < 1)
	{
		std::cerr << "UdpRelayReceiver::removeRelayClass() ERROR no relay of class installed";
		std::cerr << std::endl;

		return 0;
	}

	std::cerr << "UdpRelayReceiver::removeRelayClass() Ok, Count decremented";
	std::cerr << std::endl;

	/* if we get here we can add one */
	mClassCount[UDP_RELAY_CLASS_ALL]--;
	mClassCount[classIdx]--;

	return 1;
}


int UdpRelayReceiver::setRelayTotal(int count)
{
	RsStackMutex stack(relayMtx);   /********** LOCK MUTEX *********/

	mClassLimit[UDP_RELAY_CLASS_ALL] = count;
	mClassLimit[UDP_RELAY_CLASS_GENERAL] 	= (int)  (UDP_RELAY_FRAC_GENERAL * count);
	mClassLimit[UDP_RELAY_CLASS_FOF] 	= (int)  (UDP_RELAY_FRAC_FOF * count);
	mClassLimit[UDP_RELAY_CLASS_FRIENDS] 	= (int)  (UDP_RELAY_FRAC_FRIENDS * count);

	return count;
}


int UdpRelayReceiver::setRelayClassMax(int classIdx, int count, int bandwidth)
{
	RsStackMutex stack(relayMtx);   /********** LOCK MUTEX *********/

	/* check the idx */
	if ((classIdx < 0) || (classIdx >= UDP_RELAY_NUM_CLASS))
	{
		std::cerr << "UdpRelayReceiver::setRelayMaximum() ERROR class Idx invalid";
		std::cerr << std::endl;
		return 0;
	}	

	mClassLimit[classIdx] = count;
	mClassBandwidth[classIdx] = bandwidth;
	return 1;
}


int UdpRelayReceiver::getRelayClassMax(int classIdx)
{
	RsStackMutex stack(relayMtx);   /********** LOCK MUTEX *********/

	/* check the idx */
	if ((classIdx < 0) || (classIdx >= UDP_RELAY_NUM_CLASS))
	{
		std::cerr << "UdpRelayReceiver::getRelayMaximum() ERROR class Idx invalid";
		std::cerr << std::endl;
		return 0;
	}	

	return mClassLimit[classIdx];
}

int UdpRelayReceiver::getRelayClassBandwidth(int classIdx)
{
	RsStackMutex stack(relayMtx);   /********** LOCK MUTEX *********/

	/* check the idx */
	if ((classIdx < 0) || (classIdx >= UDP_RELAY_NUM_CLASS))
	{
		std::cerr << "UdpRelayReceiver::getRelayMaximum() ERROR class Idx invalid";
		std::cerr << std::endl;
		return 0;
	}	

	return mClassBandwidth[classIdx];
}

int UdpRelayReceiver::getRelayCount(int classIdx)
{
	RsStackMutex stack(relayMtx);   /********** LOCK MUTEX *********/

	/* check the idx */
	if ((classIdx < 0) || (classIdx >= UDP_RELAY_NUM_CLASS))
	{
		std::cerr << "UdpRelayReceiver::getRelayCount() ERROR class Idx invalid";
		std::cerr << std::endl;
		return 0;
	}	

	return mClassCount[classIdx];
}


int UdpRelayReceiver::RelayStatus(std::ostream &out)
{
        RsStackMutex stack(relayMtx);   /********** LOCK MUTEX *********/

	/* iterate through the Relays */
	out << "UdpRelayReceiver::RelayStatus()";
	out << std::endl;

	std::map<UdpRelayAddrSet, UdpRelayProxy>::iterator rit;
	for(rit = mRelays.begin(); rit != mRelays.end(); ++rit)
	{
		out << "Relay for: " << rit->first;
		out << std::endl;

		out << "\tClass: " << rit->second.mRelayClass;
		out << "\tBandwidth: " << rit->second.mBandwidth;
		out << "\tDataSize: " << rit->second.mDataSize;
		out << "\tLastBandwidthTS: " << rit->second.mLastBandwidthTS;
		out << std::endl;
	}

	out << "ClassLimits:" << std::endl;
	for(int i = 0; i < UDP_RELAY_NUM_CLASS; i++)
	{
		out << "Limit[" << i << "] = " << mClassLimit[i];
		out << " Count: " << mClassCount[i];
		out << " Bandwidth: " << mClassBandwidth[i];
		out << std::endl;
	}

	return 1;
}
	
int     UdpRelayReceiver::status(std::ostream &out)
{

	out << "UdpRelayReceiver::status()" << std::endl;
	out << "UdpRelayReceiver::Relayed Connections:" << std::endl;

	RelayStatus(out);

	{
		RsStackMutex stack(relayMtx);   /********** LOCK MUTEX *********/

		out << "UdpRelayReceiver::Connections:" << std::endl;

		std::map<struct sockaddr_in, UdpRelayEnd>::iterator pit;
		for(pit = mStreams.begin(); pit != mStreams.end(); ++pit)
		{
			out << "\t" << pit->first << " : " << pit->second;
			out << std::endl;
		}
	}

	UdpPeersStatus(out);

	return 1;
}

int UdpRelayReceiver::UdpPeersStatus(std::ostream &out)
{
        RsStackMutex stack(udppeerMtx);   /********** LOCK MUTEX *********/

	/* iterate through the Relays */
	out << "UdpRelayReceiver::UdpPeersStatus()";
	out << std::endl;

        std::map<struct sockaddr_in, UdpPeer *>::iterator pit;
	for(pit = mPeers.begin(); pit != mPeers.end(); ++pit)
	{
		out << "UdpPeer for: " << pit->first;
		out << " is: " << pit->second;
		out << std::endl;
	}
	return 1;
}


void UdpRelayReceiver::clearDataTransferred()
{
	{
	        RsStackMutex stack(relayMtx);   /********** LOCK MUTEX *********/

		mWriteBytes = 0;
		mRelayBytes = 0;
	}

	{
	        RsStackMutex stack(udppeerMtx);   /********** LOCK MUTEX *********/

		mReadBytes = 0;
	}
}


void UdpRelayReceiver::getDataTransferred(uint32_t &read, uint32_t &write, uint32_t &relay)
{
	{
	        RsStackMutex stack(relayMtx);   /********** LOCK MUTEX *********/

		write = mWriteBytes;
		relay = mRelayBytes;
	}

	{
	        RsStackMutex stack(udppeerMtx);   /********** LOCK MUTEX *********/

		read = mReadBytes;
	}
	clearDataTransferred();
}



#define UDP_RELAY_HEADER_SIZE 16

/* higher level interface */
int UdpRelayReceiver::recvPkt(void *data, int size, struct sockaddr_in &from)
{
	/* remove unused parameter warnings */
	(void) from;

	/* print packet information */
#ifdef DEBUG_UDP_RELAY_PKTS
	std::cerr << "UdpRelayReceiver::recvPkt(" << size << ") from: " << from;
	std::cerr << std::endl;
	displayUdpRelayPacketHeader(data, size);

#endif
 
	if (!isUdpRelayPacket(data, size))
	{
#ifdef DEBUG_UDP_RELAY
		std::cerr << "UdpRelayReceiver::recvPkt() ERROR: is Not RELAY Pkt";
		std::cerr << std::endl;
#endif
		return 0;
	}

	/* decide if we are the relay, or the endpoint */
	UdpRelayAddrSet addrSet;
	if (!extractUdpRelayAddrSet(data, size, addrSet))
	{
#ifdef DEBUG_UDP_RELAY_ERRORS
		std::cerr << "UdpRelayReceiver::recvPkt() ERROR: cannot extract Addresses";
		std::cerr << std::endl;
#endif
		/* fails most basic test, drop */
		return 0; 
	}

	{
	        RsStackMutex stack(relayMtx);   /********** LOCK MUTEX *********/
	
		/* lookup relay first (double entries) */
		std::map<UdpRelayAddrSet, UdpRelayProxy>::iterator rit = mRelays.find(addrSet);
		if (rit != mRelays.end())
		{
			/* we are the relay */
#ifdef DEBUG_UDP_RELAY_PKTS
			std::cerr << "UdpRelayReceiver::recvPkt() We are the Relay. Passing onto: ";
			std::cerr << rit->first.mDestAddr;
			std::cerr << std::endl;
#endif
			/* do accounting */
			rit->second.mLastTS = time(NULL);
			rit->second.mDataSize += size;

			mRelayBytes += size;
	
			mPublisher->sendPkt(data, size, rit->first.mDestAddr, STD_RELAY_TTL);
			return 1;
		}
	}

	/* otherwise we are likely to be the endpoint,
	 * use the peers Address from the header
	 */

	{
	        RsStackMutex stack(udppeerMtx);   /********** LOCK MUTEX *********/

		std::map<struct sockaddr_in, UdpPeer *>::iterator pit = mPeers.find(addrSet.mSrcAddr);
		if (pit != mPeers.end())
		{
			/* we are the end-point */
#ifdef DEBUG_UDP_RELAY_PKTS
			std::cerr << "UdpRelayReceiver::recvPkt() Sending to UdpPeer: ";
			std::cerr << pit->first;
			std::cerr << std::endl;
#endif
			mReadBytes += size;

			/* remove the header */
			void *pktdata = (void *) (((uint8_t *) data) + UDP_RELAY_HEADER_SIZE);
			int   pktsize = size - UDP_RELAY_HEADER_SIZE;
			if (pktsize > 0)
			{
				(pit->second)->recvPkt(pktdata, pktsize);
			}
			else
			{
				/* packet undersized */
//#ifdef DEBUG_UDP_RELAY
				std::cerr << "UdpRelayReceiver::recvPkt() ERROR Packet Undersized";
				std::cerr << std::endl;
//#endif
			}
			return 1;
		}
		/* done */
	}

	/* unknown */
//#ifdef DEBUG_UDP_RELAY
	std::cerr << "UdpRelayReceiver::recvPkt() Peer Unknown!";
	std::cerr << std::endl;
//#endif
	return 0;
}


/* the address here must be the end point!, 
 * it cannot be proxy, as we could be using the same proxy for multiple connections. 
 */
int UdpRelayReceiver::sendPkt(const void *data, int size, const struct sockaddr_in &to, int /*ttl*/)
{
	RsStackMutex stack(relayMtx);   /********** LOCK MUTEX *********/
	
	/* work out who the proxy is */
	std::map<struct sockaddr_in, UdpRelayEnd>::iterator it;
	it = mStreams.find(to);
	if (it == mStreams.end())
	{
//#ifdef DEBUG_UDP_RELAY
		std::cerr << "UdpRelayReceiver::sendPkt() Peer Unknown!";
		std::cerr << std::endl;
//#endif
		return 0;
	}
	
#ifdef DEBUG_UDP_RELAY_PKTS
	std::cerr << "UdpRelayReceiver::sendPkt() to Relay: " << it->second;
	std::cerr << std::endl;
#endif

	mWriteBytes += size;

	/* add a header to packet */
	int finalPktSize = createRelayUdpPacket(data, size, mTmpSendPkt, MAX_RELAY_UDP_PACKET_SIZE, &(it->second));

	/* send the packet on */
	return mPublisher->sendPkt(mTmpSendPkt, finalPktSize, it->second.mProxyAddr, STD_RELAY_TTL);
}

/***** RELAY PACKET FORMAT ****************************
 *
 *
 * [   0    |     1    |     2    |    3     ]
 *
 * [  'R'        'L'        'Y'     Version  ]
 * [     IP         Address      1           ]
 * [  Port       1    ][ IP   Address  2 ....
 * ... IP   Address  2][ Port 2              ]
 * [.... TUNNELLED DATA ....
 *
 *
 *      ... ]
 *
 * 16 Bytes: 4 ID, 6 IP:Port 1, 6 IP:Port 2 
 */

#define UDP_IDENTITY_STRING_V1	"RLY1"
#define UDP_IDENTITY_SIZE_V1	4

int isUdpRelayPacket(const void *data, const int size)
{
	if (size < UDP_RELAY_HEADER_SIZE)
		return 0;
	
	return (0 == strncmp((char *) data, UDP_IDENTITY_STRING_V1, UDP_IDENTITY_SIZE_V1));
}

#ifdef DEBUG_UDP_RELAY

int displayUdpRelayPacketHeader(const void *data, const int size)
{
	int dsize = UDP_RELAY_HEADER_SIZE + 16;
	if (size < dsize)
	{
		dsize = size;
	}

	std::string out;
	for(int i = 0; i < dsize; i++)
	{
		if ((i > 0) && (i % 16 == 0))
		{
			out += "\n";
		}

		rs_sprintf_append(out, "%02x", (uint32_t) ((uint8_t*) data)[i]);
	}

	std::cerr << "displayUdpRelayPacketHeader()" << std::endl;
	std::cerr << out;
	std::cerr << std::endl;

	return 1;
}
#endif


int extractUdpRelayAddrSet(const void *data, const int size, UdpRelayAddrSet &addrSet)
{
	if (size < UDP_RELAY_HEADER_SIZE)
	{
		std::cerr << "createRelayUdpPacket() ERROR invalid size";
		std::cerr << std::endl;
		return 0;
	}

	uint8_t *header = (uint8_t *) data;

	sockaddr_clear(&(addrSet.mSrcAddr));
	sockaddr_clear(&(addrSet.mDestAddr));

	/* as IP:Port are already in network byte order, we can just write them to the dataspace */
	uint32_t ipaddr;
	uint16_t port;

	memcpy(&ipaddr, &(header[4]), 4);	
	memcpy(&port, &(header[8]), 2);	

 	addrSet.mSrcAddr.sin_addr.s_addr = ipaddr;
 	addrSet.mSrcAddr.sin_port = port;

	memcpy(&ipaddr, &(header[10]), 4);	
	memcpy(&port, &(header[14]), 2);	

 	addrSet.mDestAddr.sin_addr.s_addr = ipaddr;
 	addrSet.mDestAddr.sin_port = port;

	return 1;
}


int createRelayUdpPacket(const void *data, const int size, void *newpkt, int newsize, UdpRelayEnd *ure)
{
	int pktsize = size + UDP_RELAY_HEADER_SIZE;
	if (newsize < pktsize)
	{
		std::cerr << "createRelayUdpPacket() ERROR invalid size";
		std::cerr << std::endl;
		std::cerr << "Incoming DataSize: " << size << " + Header: " << UDP_RELAY_HEADER_SIZE;
		std::cerr << " > " << newsize;
		std::cerr << std::endl;
		return 0;
	}
	uint8_t *header = (uint8_t *) newpkt;
	memcpy(header, UDP_IDENTITY_STRING_V1, UDP_IDENTITY_SIZE_V1);

	/* as IP:Port are already in network byte order, we can just write them to the dataspace */
	uint32_t ipaddr = ure->mLocalAddr.sin_addr.s_addr;
	uint16_t port = ure->mLocalAddr.sin_port;

	memcpy(&(header[4]), &ipaddr, 4);	
	memcpy(&(header[8]), &port, 2);	

	ipaddr = ure->mRemoteAddr.sin_addr.s_addr;
	port = ure->mRemoteAddr.sin_port;

	memcpy(&(header[10]), &ipaddr, 4);	
	memcpy(&(header[14]), &port, 2);	

	memcpy(&(header[16]), data, size);

	return pktsize;
}



/******* Small Container Class Helper Functions ****/

UdpRelayAddrSet::UdpRelayAddrSet()
{
	sockaddr_clear(&mSrcAddr);
	sockaddr_clear(&mDestAddr);
}

UdpRelayAddrSet::UdpRelayAddrSet(const sockaddr_in *ownAddr, const sockaddr_in *destAddr)
{
	mSrcAddr = *ownAddr;
	mDestAddr = *destAddr;
}

UdpRelayAddrSet UdpRelayAddrSet::flippedSet()
{	
	UdpRelayAddrSet flipped(&mDestAddr, &mSrcAddr);
	return flipped;
}


int operator<(const UdpRelayAddrSet &a, const UdpRelayAddrSet &b)
{
	if (a.mSrcAddr < b.mSrcAddr)
	{
		return 1;
	}

	if (a.mSrcAddr == b.mSrcAddr)
	{
		if (a.mDestAddr < b.mDestAddr)
		{
			return 1;
		}
	}
	return 0;
}


UdpRelayProxy::UdpRelayProxy()
{
	mBandwidth = 0;
	mDataSize = 0;
	mLastBandwidthTS = 0;
	mLastTS = time(NULL); // Must be set here, otherwise Proxy Timesout before anything can happen!
	mRelayClass = 0;

        mStartTS = time(NULL);
        mBandwidthLimit = 0;
}

UdpRelayProxy::UdpRelayProxy(UdpRelayAddrSet *addrSet, int relayClass, uint32_t bandwidth)
	: mAddrs(*addrSet),
	  mBandwidth(0),
	  mDataSize(0),
	  mLastBandwidthTS(0),
	  mLastTS(time(NULL)),
	  mStartTS(time(NULL)),
      mBandwidthLimit(bandwidth),
      mRelayClass(relayClass)
{
	/* bandwidth fallback */
	if (bandwidth == 0)
	{
		switch(relayClass)
		{
			default:
		    case UDP_RELAY_CLASS_GENERAL:
	        		mBandwidthLimit = RELAY_MAX_BANDWIDTH;
				break;
		    case UDP_RELAY_CLASS_FOF:
	        		mBandwidthLimit = RELAY_MAX_BANDWIDTH;
				break;
		    case UDP_RELAY_CLASS_FRIENDS:
	        		mBandwidthLimit = RELAY_MAX_BANDWIDTH;
				break;
		}
	}
}

UdpRelayEnd::UdpRelayEnd() 
{ 
	sockaddr_clear(&mLocalAddr);
	sockaddr_clear(&mProxyAddr);
	sockaddr_clear(&mRemoteAddr);

}

UdpRelayEnd::UdpRelayEnd(UdpRelayAddrSet *endPoints, const struct sockaddr_in *proxyaddr)
{
	mLocalAddr = endPoints->mSrcAddr;
	mRemoteAddr = endPoints->mDestAddr;
	mProxyAddr = *proxyaddr;
}





std::ostream &operator<<(std::ostream &out, const UdpRelayAddrSet &uras)
{
	out << "<" << uras.mSrcAddr << "," << uras.mDestAddr << ">";
	return out;
}

std::ostream &operator<<(std::ostream &out, const UdpRelayProxy &urp)
{
	rstime_t now = time(NULL);
	out << "UdpRelayProxy for " << urp.mAddrs;
	out << std::endl;
	out << "\tRelayClass: " << urp.mRelayClass;
	out << std::endl;
	out << "\tBandwidth: " << urp.mBandwidth;
	out << std::endl;
	out << "\tDataSize: " << urp.mDataSize;
	out << std::endl;
	out << "\tLastBandwidthTS: " << now - urp.mLastBandwidthTS << " secs ago";
	out << std::endl;
	out << "\tLastTS: " << now - urp.mLastTS << " secs ago";
	out << std::endl;

	return out;
}

std::ostream &operator<<(std::ostream &out, const UdpRelayEnd &ure)
{
	out << "UdpRelayEnd: <" << ure.mLocalAddr << " => " << ure.mProxyAddr << " <= ";
	out << ure.mRemoteAddr << ">";
	return out;
}