/*
 *  Original work: Copyright (c) 2014, Oculus VR, Inc.
 *  All rights reserved.
 *
 *  This source code is licensed under the BSD-style license found in the
 *  RakNet License.txt file in the licenses directory of this source tree. An additional grant 
 *  of patent rights can be found in the RakNet Patents.txt file in the same directory.
 *
 *
 *  Modified work: Copyright (c) 2016-2020, SLikeSoft UG (haftungsbeschränkt)
 *
 *  This source code was modified by SLikeSoft. Modifications are licensed under the MIT-style
 *  license found in the license.txt file in the root directory of this source tree.
 */

#include "slikenet/UDPForwarder.h"

#if _RAKNET_SUPPORT_UDPForwarder==1

#include "slikenet/GetTime.h"
#include "slikenet/MTUSize.h"
#include "slikenet/SocketLayer.h"
#include "slikenet/WSAStartupSingleton.h"
#include "slikenet/sleep.h"
#include "slikenet/DS_OrderedList.h"
#include "slikenet/LinuxStrings.h"
#include "slikenet/SocketDefines.h"
#include "slikenet/VitaIncludes.h"
#include "errno.h"

#ifdef _WIN32
#include <tchar.h>
#else
#ifndef _T
#define _T(x) (x)
#endif
#include <sys/types.h>  // used for getaddrinfo()
#include <sys/socket.h> // used for getaddrinfo()
#include <netdb.h>      // used for getaddrinfo()
#endif

#ifndef INVALID_SOCKET
#define INVALID_SOCKET -1
#endif

using namespace SLNet;
static const unsigned short DEFAULT_MAX_FORWARD_ENTRIES=64;

namespace SLNet
{
	RAK_THREAD_DECLARATION(UpdateUDPForwarderGlobal);
}

UDPForwarder::ForwardEntry::ForwardEntry()
{
	socket=INVALID_SOCKET;
	timeLastDatagramForwarded= SLNet::GetTimeMS();
	addr1Confirmed=UNASSIGNED_SYSTEM_ADDRESS;
	addr2Confirmed=UNASSIGNED_SYSTEM_ADDRESS;
}
UDPForwarder::ForwardEntry::~ForwardEntry() {
	if (socket!=INVALID_SOCKET)
		closesocket__(socket);
}

UDPForwarder::UDPForwarder()
{
#ifdef _WIN32
	WSAStartupSingleton::AddRef();
#endif

	maxForwardEntries=DEFAULT_MAX_FORWARD_ENTRIES;
	nextInputId=0;
	startForwardingInput.SetPageSize(sizeof(StartForwardingInputStruct)*16);
	stopForwardingCommands.SetPageSize(sizeof(StopForwardingStruct)*16);
}
UDPForwarder::~UDPForwarder()
{
	Shutdown();

#ifdef _WIN32
	WSAStartupSingleton::Deref();
#endif
}
void UDPForwarder::Startup(void)
{
	if (isRunning.GetValue()>0)
		return;

	isRunning.Increment();

	int errorCode;



	errorCode = SLNet::RakThread::Create(UpdateUDPForwarderGlobal, this);

	if ( errorCode != 0 )
	{
		RakAssert(0);
		return;
	}

	while (threadRunning.GetValue()==0)
		RakSleep(30);
}
void UDPForwarder::Shutdown(void)
{
	if (isRunning.GetValue()==0)
		return;
	isRunning.Decrement();

	while (threadRunning.GetValue()>0)
		RakSleep(30);

	unsigned int j;
	for (j=0; j < forwardListNotUpdated.Size(); j++)
		SLNet::OP_DELETE(forwardListNotUpdated[j],_FILE_AND_LINE_);
	forwardListNotUpdated.Clear(false, _FILE_AND_LINE_);
}
void UDPForwarder::SetMaxForwardEntries(unsigned short maxEntries)
{
	RakAssert(maxEntries>0 && maxEntries<65535/2);
	maxForwardEntries=maxEntries;
}
int UDPForwarder::GetMaxForwardEntries(void) const
{
	return maxForwardEntries;
}
int UDPForwarder::GetUsedForwardEntries(void) const
{
	return (int) forwardListNotUpdated.Size();
}
UDPForwarderResult UDPForwarder::StartForwarding(SystemAddress source, SystemAddress destination, SLNet::TimeMS timeoutOnNoDataMS, const char *forceHostAddress, unsigned short socketFamily,
								  unsigned short *forwardingPort, __UDPSOCKET__ *forwardingSocket)
{
	// Invalid parameters?
	if (timeoutOnNoDataMS == 0 || timeoutOnNoDataMS > UDP_FORWARDER_MAXIMUM_TIMEOUT || source==UNASSIGNED_SYSTEM_ADDRESS || destination==UNASSIGNED_SYSTEM_ADDRESS)
		return UDPFORWARDER_INVALID_PARAMETERS;

	if (isRunning.GetValue()==0)
		return UDPFORWARDER_NOT_RUNNING;

	(void) socketFamily;

	unsigned int inputId = nextInputId++;

	StartForwardingInputStruct *sfis;
	sfis = startForwardingInput.Allocate(_FILE_AND_LINE_);
	sfis->source=source;
	sfis->destination=destination;
	sfis->timeoutOnNoDataMS=timeoutOnNoDataMS;
	RakAssert(timeoutOnNoDataMS!=0);
	if (forceHostAddress && forceHostAddress[0])
		sfis->forceHostAddress=forceHostAddress;
	sfis->socketFamily=socketFamily;
	sfis->inputId=inputId;
	startForwardingInput.Push(sfis);

	for(;;)
	{
		RakSleep(0);
		startForwardingOutputMutex.Lock();
		for (unsigned int i=0; i < startForwardingOutput.Size(); i++)
		{
			if (startForwardingOutput[i].inputId==inputId)
			{
				if (startForwardingOutput[i].result==UDPFORWARDER_SUCCESS)
				{
					if (forwardingPort)
						*forwardingPort = startForwardingOutput[i].forwardingPort;
					if (forwardingSocket)
						*forwardingSocket = startForwardingOutput[i].forwardingSocket;
				}
				UDPForwarderResult res = startForwardingOutput[i].result;
				startForwardingOutput.RemoveAtIndex(i);
				startForwardingOutputMutex.Unlock();
				return res;
			}
		}
		startForwardingOutputMutex.Unlock();
	}
}
void UDPForwarder::StopForwarding(SystemAddress source, SystemAddress destination)
{
	StopForwardingStruct *sfs;
	sfs = stopForwardingCommands.Allocate(_FILE_AND_LINE_);
	sfs->destination=destination;
	sfs->source=source;
	stopForwardingCommands.Push(sfs);
}
void UDPForwarder::RecvFrom(SLNet::TimeMS curTime, ForwardEntry *forwardEntry)
{
#ifndef __native_client__
	char data[ MAXIMUM_MTU_SIZE ];

#if RAKNET_SUPPORT_IPV6==1
	sockaddr_storage their_addr;
	memset(&their_addr,0,sizeof(their_addr));
	sockaddr* sockAddrPtr;
	socklen_t sockLen;
	socklen_t* socketlenPtr=(socklen_t*) &sockLen;
	sockaddr_in *sockAddrIn;
	sockaddr_in6 *sockAddrIn6;
	sockLen=sizeof(their_addr);
	sockAddrPtr=(sockaddr*) &their_addr;
#else
	sockaddr_in sockAddrIn;
	memset(&sockAddrIn,0,sizeof(sockaddr_in));
	socklen_t len2;
	len2 = sizeof( sockAddrIn );
	sockAddrIn.sin_family = AF_INET;
#endif

#if defined(__GNUC__)
	#if defined(MSG_DONTWAIT)
		const int flag=MSG_DONTWAIT;
	#else
		const int flag=0x40;
	#endif
#else
	const int flag=0;
#endif

	int receivedDataLen, len=0;
	//unsigned short portnum=0;

#if RAKNET_SUPPORT_IPV6==1
	receivedDataLen = recvfrom__( forwardEntry->socket, data, MAXIMUM_MTU_SIZE, flag, sockAddrPtr, socketlenPtr );
#else
	receivedDataLen = recvfrom__( forwardEntry->socket, data, MAXIMUM_MTU_SIZE, flag, ( sockaddr* ) & sockAddrIn, ( socklen_t* ) & len2 );
#endif

	if (receivedDataLen<0)
	{
#if defined(_WIN32) && defined(_DEBUG) && !defined(WINDOWS_PHONE_8) && !defined(WINDOWS_STORE_RT)
		DWORD dwIOError = WSAGetLastError();

		if (dwIOError!=WSAECONNRESET && dwIOError!=WSAEINTR && dwIOError!=WSAETIMEDOUT && dwIOError!=WSAEWOULDBLOCK)
		{
			LPTSTR messageBuffer;
			FormatMessage( FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
				nullptr, dwIOError, MAKELANGID( LANG_NEUTRAL, SUBLANG_DEFAULT ),  // Default language
				( LPTSTR ) & messageBuffer, 0, nullptr);
			// something has gone wrong here...
			RAKNET_DEBUG_TPRINTF( _T("recvfrom failed:Error code - %lu\n%s"), dwIOError, messageBuffer );

			//Free the buffer.
			LocalFree( messageBuffer );
		}
#else
		if (errno!=EAGAIN
			&& errno!=0
#if defined(__GNUC__)
			&& errno!=EWOULDBLOCK
#endif
			)
		{
			printf("errno=%i\n", errno);
		}
#endif

		
	}

	if (receivedDataLen<=0)
		return;

	SystemAddress receivedAddr;
#if RAKNET_SUPPORT_IPV6==1
	if (their_addr.ss_family==AF_INET)
	{
		sockAddrIn=(sockaddr_in *)&their_addr;
		sockAddrIn6=0;
		memcpy(&receivedAddr.address.addr4,sockAddrIn,sizeof(sockaddr_in));
	}
	else
	{
		sockAddrIn=0;
		sockAddrIn6=(sockaddr_in6 *)&their_addr;
		memcpy(&receivedAddr.address.addr6,sockAddrIn6,sizeof(sockaddr_in6));
	}
#else
	memcpy(&receivedAddr.address.addr4,&sockAddrIn,sizeof(sockaddr_in));
#endif
	//portnum=receivedAddr.GetPort();

	SystemAddress forwardTarget;

	bool confirmed1 = forwardEntry->addr1Confirmed!=UNASSIGNED_SYSTEM_ADDRESS;
	bool confirmed2 = forwardEntry->addr2Confirmed!=UNASSIGNED_SYSTEM_ADDRESS;
	bool matchConfirmed1 =
		confirmed1 &&
		forwardEntry->addr1Confirmed==receivedAddr;
	bool matchConfirmed2 =
		confirmed2 &&
		forwardEntry->addr2Confirmed==receivedAddr;
	bool matchUnconfirmed1 = forwardEntry->addr1Unconfirmed.EqualsExcludingPort(receivedAddr);
	bool matchUnconfirmed2 = forwardEntry->addr2Unconfirmed.EqualsExcludingPort(receivedAddr);

	if (matchConfirmed1==true || (matchConfirmed2==false && confirmed1==false && matchUnconfirmed1==true))
	{
		// Forward to addr2
		if (forwardEntry->addr1Confirmed==UNASSIGNED_SYSTEM_ADDRESS)
		{
			forwardEntry->addr1Confirmed=receivedAddr;
		}
		if (forwardEntry->addr2Confirmed!=UNASSIGNED_SYSTEM_ADDRESS)
			forwardTarget=forwardEntry->addr2Confirmed;
		else
			forwardTarget=forwardEntry->addr2Unconfirmed;
	}
	else if (matchConfirmed2==true || (confirmed2==false && matchUnconfirmed2==true))
	{
		// Forward to addr1
		if (forwardEntry->addr2Confirmed==UNASSIGNED_SYSTEM_ADDRESS)
		{
			forwardEntry->addr2Confirmed=receivedAddr;
		}
		if (forwardEntry->addr1Confirmed!=UNASSIGNED_SYSTEM_ADDRESS)
			forwardTarget=forwardEntry->addr1Confirmed;
		else
			forwardTarget=forwardEntry->addr1Unconfirmed;
	}
	else
	{
		return;
	}

	// Forward to dest
	len=0;
// 	sockaddr_in saOut;
// 	saOut.sin_port = forwardTarget.GetPortNetworkOrder(); // User port
// 	saOut.sin_addr.s_addr = forwardTarget.address.addr4.sin_addr.s_addr;
// 	saOut.sin_family = AF_INET;
	do
	{



#if RAKNET_SUPPORT_IPV6==1
		if (forwardTarget.address.addr4.sin_family==AF_INET)
		{
			do
			{
				len = sendto__( forwardEntry->socket, data, receivedDataLen, 0, ( const sockaddr* ) & forwardTarget.address.addr4, sizeof( sockaddr_in ) );
			}
			while ( len == 0 );
		}
		else
		{
			do
			{
				len = sendto__( forwardEntry->socket, data, receivedDataLen, 0, ( const sockaddr* ) & forwardTarget.address.addr6, sizeof( sockaddr_in6 ) );
			}
			while ( len == 0 );
		}
#else
		do
		{
			len = sendto__( forwardEntry->socket, data, receivedDataLen, 0, ( const sockaddr* ) & forwardTarget.address.addr4, sizeof( sockaddr_in ) );
		}
		while ( len == 0 );
#endif






























	}
	while ( len == 0 );

	forwardEntry->timeLastDatagramForwarded=curTime;
#endif  // __native_client__
}
void UDPForwarder::UpdateUDPForwarder(void)
{
	/*
#if !defined(SN_TARGET_PSP2)
	timeval tv;
	tv.tv_sec=0;
	tv.tv_usec=0;
#endif
	*/

	SLNet::TimeMS curTime = SLNet::GetTimeMS();

	StartForwardingInputStruct *sfis;
	StartForwardingOutputStruct sfos;
	sfos.forwardingSocket=INVALID_SOCKET;
	sfos.forwardingPort=0;
	sfos.inputId=0;
	sfos.result=UDPFORWARDER_RESULT_COUNT;

	for(;;)
	{
		sfis = startForwardingInput.Pop();
		if (sfis==0)
			break;

		if (GetUsedForwardEntries()>maxForwardEntries)
		{
			sfos.result=UDPFORWARDER_NO_SOCKETS;
		}
		else
		{
			sfos.result=UDPFORWARDER_RESULT_COUNT;

			for (unsigned int i=0; i < forwardListNotUpdated.Size(); i++)
			{
				if (
					(forwardListNotUpdated[i]->addr1Unconfirmed==sfis->source &&
					forwardListNotUpdated[i]->addr2Unconfirmed==sfis->destination)
					||
					(forwardListNotUpdated[i]->addr1Unconfirmed==sfis->destination &&
					forwardListNotUpdated[i]->addr2Unconfirmed==sfis->source)
					)
				{
					ForwardEntry *fe = forwardListNotUpdated[i];
					sfos.forwardingPort = SocketLayer::GetLocalPort ( fe->socket );
					sfos.forwardingSocket=fe->socket;
					sfos.result=UDPFORWARDER_FORWARDING_ALREADY_EXISTS;
					break;
				}
			}

			if (sfos.result==UDPFORWARDER_RESULT_COUNT)
			{
				int sock_opt;
				sockaddr_in listenerSocketAddress;
				listenerSocketAddress.sin_port = 0;
				ForwardEntry *fe = SLNet::OP_NEW<UDPForwarder::ForwardEntry>(_FILE_AND_LINE_);
				fe->addr1Unconfirmed=sfis->source;
				fe->addr2Unconfirmed=sfis->destination;
				fe->timeoutOnNoDataMS=sfis->timeoutOnNoDataMS;

#if RAKNET_SUPPORT_IPV6!=1
				fe->socket = socket__( AF_INET, SOCK_DGRAM, 0 );
				listenerSocketAddress.sin_family = AF_INET;
				if (sfis->forceHostAddress.IsEmpty()==false)
				{




					inet_pton(AF_INET, sfis->forceHostAddress.C_String(), &listenerSocketAddress.sin_addr.s_addr);

				}
				else
				{
					listenerSocketAddress.sin_addr.s_addr = INADDR_ANY;
				}
				int ret = bind__( fe->socket, ( struct sockaddr * ) & listenerSocketAddress, sizeof( listenerSocketAddress ) );
				if (ret==-1)
				{
					SLNet::OP_DELETE(fe,_FILE_AND_LINE_);
					sfos.result=UDPFORWARDER_BIND_FAILED;
				}
				else
				{
					sfos.result=UDPFORWARDER_SUCCESS;
				}

#else // RAKNET_SUPPORT_IPV6==1
				struct addrinfo hints;
				memset(&hints, 0, sizeof (addrinfo)); // make sure the struct is empty
				hints.ai_family = sfis->socketFamily;
				hints.ai_socktype = SOCK_DGRAM; // UDP sockets
				hints.ai_flags = AI_PASSIVE;     // fill in my IP for me
				struct addrinfo *servinfo=0, *aip;  // will point to the results

				if (sfis->forceHostAddress.IsEmpty() || sfis->forceHostAddress=="UNASSIGNED_SYSTEM_ADDRESS")
					getaddrinfo(0, "0", &hints, &servinfo);
				else
					getaddrinfo(sfis->forceHostAddress.C_String(), "0", &hints, &servinfo);

				for (aip = servinfo; aip != nullptr; aip = aip->ai_next)
				{
					// Open socket. The address type depends on what
					// getaddrinfo() gave us.
					fe->socket = socket__(aip->ai_family, aip->ai_socktype, aip->ai_protocol);
					if (fe->socket != INVALID_SOCKET)
					{
						int ret = bind__( fe->socket, aip->ai_addr, (int) aip->ai_addrlen );
						if (ret>=0)
						{
							break;
						}
						else
						{
							closesocket__(fe->socket);
							fe->socket=INVALID_SOCKET;
						}
					}
				}

				if (fe->socket==INVALID_SOCKET)
					sfos.result=UDPFORWARDER_BIND_FAILED;
				else
					sfos.result=UDPFORWARDER_SUCCESS;
#endif  // RAKNET_SUPPORT_IPV6==1

				if (sfos.result==UDPFORWARDER_SUCCESS)
				{
					sfos.forwardingPort = SocketLayer::GetLocalPort ( fe->socket );
					sfos.forwardingSocket=fe->socket;

					sock_opt=1024*256;
					setsockopt__(fe->socket, SOL_SOCKET, SO_RCVBUF, ( char * ) & sock_opt, sizeof ( sock_opt ) );
					sock_opt=0;
					setsockopt__(fe->socket, SOL_SOCKET, SO_LINGER, ( char * ) & sock_opt, sizeof ( sock_opt ) );
#ifdef _WIN32
					unsigned long nonblocking = 1;
					ioctlsocket__( fe->socket, FIONBIO, &nonblocking );



#else
					fcntl( fe->socket, F_SETFL, O_NONBLOCK );
#endif

					forwardListNotUpdated.Insert(fe,_FILE_AND_LINE_);
				}
			}
		}

		// Push result
		sfos.inputId=sfis->inputId;
		startForwardingOutputMutex.Lock();
		startForwardingOutput.Push(sfos,_FILE_AND_LINE_);
		startForwardingOutputMutex.Unlock();

		startForwardingInput.Deallocate(sfis, _FILE_AND_LINE_);
	}

	StopForwardingStruct *sfs;

	for(;;)
	{
		sfs = stopForwardingCommands.Pop();
		if (sfs==0)
			break;

		ForwardEntry *fe;
		for (unsigned int i=0; i < forwardListNotUpdated.Size(); i++)
		{
			if (
				(forwardListNotUpdated[i]->addr1Unconfirmed==sfs->source &&
				forwardListNotUpdated[i]->addr2Unconfirmed==sfs->destination)
				||
				(forwardListNotUpdated[i]->addr1Unconfirmed==sfs->destination &&
				forwardListNotUpdated[i]->addr2Unconfirmed==sfs->source)
				)
			{
				fe = forwardListNotUpdated[i];
				forwardListNotUpdated.RemoveAtIndexFast(i);
				SLNet::OP_DELETE(fe, _FILE_AND_LINE_);
				break;
			}
		}

		stopForwardingCommands.Deallocate(sfs, _FILE_AND_LINE_);
	}

	unsigned int i;

	i=0;
	while (i < forwardListNotUpdated.Size())
	{
		if (curTime > forwardListNotUpdated[i]->timeLastDatagramForwarded && // Account for timestamp wrap
			curTime > forwardListNotUpdated[i]->timeLastDatagramForwarded+forwardListNotUpdated[i]->timeoutOnNoDataMS)
		{
			SLNet::OP_DELETE(forwardListNotUpdated[i],_FILE_AND_LINE_);
			forwardListNotUpdated.RemoveAtIndex(i);
		}
		else
			i++;
	}

	ForwardEntry *forwardEntry;
	for (i=0; i < forwardListNotUpdated.Size(); i++)
	{
		forwardEntry = forwardListNotUpdated[i];
		RecvFrom(curTime, forwardEntry);
	}
}

namespace SLNet {
RAK_THREAD_DECLARATION(UpdateUDPForwarderGlobal)
{



	UDPForwarder * udpForwarder = ( UDPForwarder * ) arguments;


	udpForwarder->threadRunning.Increment();
	while (udpForwarder->isRunning.GetValue()>0)
	{
		udpForwarder->UpdateUDPForwarder();

		// 12/1/2010 Do not change from 0
		// See http://www.jenkinssoftware.com/forum/index.php?topic=4033.0;topicseen
		// Avoid 100% reported CPU usage
		if (udpForwarder->forwardListNotUpdated.Size()==0)
			RakSleep(30);
		else
			RakSleep(0);
	}
	udpForwarder->threadRunning.Decrement();
	



	return 0;


}

} // namespace SLNet

#endif // #if _RAKNET_SUPPORT_FileOperations==1