/*
 *  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) 2016-2017, 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.
 */

/// \file
/// \brief A simple TCP based server allowing sends and receives.  Can be connected by any TCP client, including telnet.
///


#include "NativeFeatureIncludes.h"
#if _RAKNET_SUPPORT_TCPInterface==1

#ifndef __SIMPLE_TCP_SERVER
#define __SIMPLE_TCP_SERVER

#include "memoryoverride.h"
#include "DS_List.h"
#include "types.h"
#include "Export.h"
#include "thread.h"
#include "DS_Queue.h"
#include "SimpleMutex.h"
#include "defines.h"
#include "SocketIncludes.h"
#include "DS_ByteQueue.h"
#include "DS_ThreadsafeAllocatingQueue.h"
#include "LocklessTypes.h"
#include "PluginInterface2.h"

#if OPEN_SSL_CLIENT_SUPPORT==1
#include <openssl/crypto.h>
#include <openssl/x509.h>
#include <openssl/pem.h>
#include <openssl/ssl.h>
#include <openssl/err.h>
#endif

namespace SLNet
{
/// Forward declarations
struct RemoteClient;

/// \internal
/// \brief As the name says, a simple multithreaded TCP server.  Used by TelnetTransport
class RAK_DLL_EXPORT TCPInterface
{
public:
	// GetInstance() and DestroyInstance(instance*)
	STATIC_FACTORY_DECLARATIONS(TCPInterface)

	TCPInterface();
	virtual ~TCPInterface();

	// TODO - add socketdescriptor
	/// Starts the TCP server on the indicated port
	/// \param[in] port Which port to listen on.
	/// \param[in] maxIncomingConnections Max incoming connections we will accept
	/// \param[in] maxConnections Max total connections, which should be >= maxIncomingConnections
	/// \param[in] threadPriority Passed to the thread creation routine. Use THREAD_PRIORITY_NORMAL for Windows. For Linux based systems, you MUST pass something reasonable based on the thread priorities for your application.
	/// \param[in] socketFamily IP version: For IPV4, use AF_INET (default). For IPV6, use AF_INET6. To autoselect, use AF_UNSPEC.
	bool Start(unsigned short port, unsigned short maxIncomingConnections, unsigned short maxConnections=0, int _threadPriority=-99999, unsigned short socketFamily=AF_INET, const char *bindAddress=0);

	/// Stops the TCP server
	void Stop(void);

	/// Connect to the specified host on the specified port
	SystemAddress Connect(const char* host, unsigned short remotePort, bool block=true, unsigned short socketFamily=AF_INET, const char *bindAddress=0);

#if OPEN_SSL_CLIENT_SUPPORT==1
	/// Start SSL on an existing connection, notified with HasCompletedConnectionAttempt
	void StartSSLClient(SystemAddress systemAddress);

	/// Was SSL started on this socket?
	bool IsSSLActive(SystemAddress systemAddress);
#endif

	/// Sends a byte stream
	virtual void Send( const char *data, unsigned int length, const SystemAddress &systemAddress, bool broadcast );

	// Sends a concatenated list of byte streams
	virtual bool SendList( const char **data, const unsigned int  *lengths, const int numParameters, const SystemAddress &systemAddress, bool broadcast );

	// Get how many bytes are waiting to be sent. If too many, you may want to skip sending
	unsigned int GetOutgoingDataBufferSize(SystemAddress systemAddress) const;

	/// Returns if Receive() will return data
	/// Do not use on PacketizedTCP
	virtual bool ReceiveHasPackets( void );

	/// Returns data received
	virtual Packet* Receive( void );

	/// Disconnects a player/address
	void CloseConnection( SystemAddress systemAddress );

	/// Deallocates a packet returned by Receive
	void DeallocatePacket( Packet *packet );

	/// Fills the array remoteSystems with the SystemAddress of all the systems we are connected to
	/// \param[out] remoteSystems An array of SystemAddress structures to be filled with the SystemAddresss of the systems we are connected to. Pass 0 to remoteSystems to only get the number of systems we are connected to
	/// \param[in, out] numberOfSystems As input, the size of remoteSystems array.  As output, the number of elements put into the array 
	void GetConnectionList( SystemAddress *remoteSystems, unsigned short *numberOfSystems ) const;

	/// Returns just the number of connections we have
	unsigned short GetConnectionCount(void) const;

	/// Has a previous call to connect succeeded?
	/// \return UNASSIGNED_SYSTEM_ADDRESS = no. Anything else means yes.
	SystemAddress HasCompletedConnectionAttempt(void);

	/// Has a previous call to connect failed?
	/// \return UNASSIGNED_SYSTEM_ADDRESS = no. Anything else means yes.
	SystemAddress HasFailedConnectionAttempt(void);

	/// Queued events of new incoming connections
	SystemAddress HasNewIncomingConnection(void);

	/// Queued events of lost connections
	SystemAddress HasLostConnection(void);

	/// Return an allocated but empty packet, for custom use
	Packet* AllocatePacket(unsigned dataSize);

	// Push a packet back to the queue
	virtual void PushBackPacket( Packet *packet, bool pushAtHead );

	/// Returns if Start() was called successfully
	bool WasStarted(void) const;

	void AttachPlugin( PluginInterface2 *plugin );
	void DetachPlugin( PluginInterface2 *plugin );
protected:

	Packet* ReceiveInt( void );

#if defined(WINDOWS_STORE_RT)
	bool CreateListenSocket_WinStore8(unsigned short port, unsigned short maxIncomingConnections, unsigned short socketFamily, const char *hostAddress);
#else
	bool CreateListenSocket(unsigned short port, unsigned short maxIncomingConnections, unsigned short socketFamily, const char *hostAddress);
#endif

	// Plugins
	DataStructures::List<PluginInterface2*> messageHandlerList;

	SLNet::LocklessUint32_t isStarted, threadRunning;
	__TCPSOCKET__ listenSocket;

	DataStructures::Queue<Packet*> headPush, tailPush;
	RemoteClient* remoteClients;
	unsigned short remoteClientsLength;

	// Assuming remoteClients is only used by one thread!
	// DataStructures::List<RemoteClient*> remoteClients;
	// Use this thread-safe queue to add to remoteClients
	// DataStructures::Queue<RemoteClient*> remoteClientsInsertionQueue;
	// SimpleMutex remoteClientsInsertionQueueMutex;

	/*
	struct OutgoingMessage
	{
		unsigned char* data;
		SystemAddress systemAddress;
		bool broadcast;
		unsigned int length;
	};
	*/
//	DataStructures::SingleProducerConsumer<OutgoingMessage> outgoingMessages;
//	DataStructures::SingleProducerConsumer<Packet> incomingMessages;
//	DataStructures::SingleProducerConsumer<SystemAddress> newIncomingConnections, lostConnections, requestedCloseConnections;
//	DataStructures::SingleProducerConsumer<RemoteClient*> newRemoteClients;
//	DataStructures::ThreadsafeAllocatingQueue<OutgoingMessage> outgoingMessages;
	DataStructures::ThreadsafeAllocatingQueue<Packet> incomingMessages;
	DataStructures::ThreadsafeAllocatingQueue<SystemAddress> newIncomingConnections, lostConnections, requestedCloseConnections;
	DataStructures::ThreadsafeAllocatingQueue<RemoteClient*> newRemoteClients;
	SimpleMutex completedConnectionAttemptMutex, failedConnectionAttemptMutex;
	DataStructures::Queue<SystemAddress> completedConnectionAttempts, failedConnectionAttempts;

	int threadPriority;

	DataStructures::List<__TCPSOCKET__> blockingSocketList;
	SimpleMutex blockingSocketListMutex;





	friend RAK_THREAD_DECLARATION(UpdateTCPInterfaceLoop);
	friend RAK_THREAD_DECLARATION(ConnectionAttemptLoop);

//	void DeleteRemoteClient(RemoteClient *remoteClient, fd_set *exceptionFD);
//	void InsertRemoteClient(RemoteClient* remoteClient);
	__TCPSOCKET__ SocketConnect(const char* host, unsigned short remotePort, unsigned short socketFamily, const char *bindAddress);

	struct ThisPtrPlusSysAddr
	{
		TCPInterface *tcpInterface;
		SystemAddress systemAddress;
		bool useSSL;
		char bindAddress[64];
		unsigned short socketFamily;
	};

#if OPEN_SSL_CLIENT_SUPPORT==1
	SSL_CTX* ctx;
	SSL_METHOD *meth;
	DataStructures::ThreadsafeAllocatingQueue<SystemAddress> startSSL;
	DataStructures::List<SystemAddress> activeSSLConnections;
	SimpleMutex sharedSslMutex;
#endif
};

/// Stores information about a remote client.
struct RemoteClient
{
	RemoteClient() {
#if OPEN_SSL_CLIENT_SUPPORT==1
		ssl=0;
#endif
		isActive=false;
#if !defined(WINDOWS_STORE_RT)
		socket=0;
#endif
	}
	__TCPSOCKET__ socket;
	SystemAddress systemAddress;
	DataStructures::ByteQueue outgoingData;
	bool isActive;
	SimpleMutex outgoingDataMutex;
	SimpleMutex isActiveMutex;

#if OPEN_SSL_CLIENT_SUPPORT==1
	SSL*     ssl;
	bool InitSSL(SSL_CTX* ctx, SSL_METHOD *meth);
	void DisconnectSSL(void);
	void FreeSSL(void);
	int Send(const char *data, unsigned int length);
	int Recv(char *data, const int dataSize);
#else
	int Send(const char *data, unsigned int length);
	int Recv(char *data, const int dataSize);
#endif
	void Reset(void)
	{
		outgoingDataMutex.Lock();
		outgoingData.Clear(_FILE_AND_LINE_);
		outgoingDataMutex.Unlock();
	}
	void SetActive(bool a);
	void SendOrBuffer(const char **data, const unsigned int *lengths, const int numParameters);
};

} // namespace SLNet

#endif

#endif // _RAKNET_SUPPORT_*