/*
 * Copyright: JessMA Open Source (ldcsaa@gmail.com)
 *
 * Author	: Bruce Liang
 * Website	: https://github.com/ldcsaa
 * Project	: https://github.com/ldcsaa/HP-Socket
 * Blog		: http://www.cnblogs.com/ldcsaa
 * Wiki		: http://www.oschina.net/p/hp-socket
 * QQ Group	: 44636872, 75375912
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
 
#pragma once

#include "SocketHelper.h"
#include "./common/GeneralHelper.h"
#include "./common/IODispatcher.h"

#ifdef _UDP_SUPPORT

class CUdpServer : public IUdpServer, private CIOHandler
{
	using CWorkerThread	 = CThread<CUdpServer, VOID, UINT>;
	using CSendQueue	 = CCASSimpleQueue<CONNID>;
	using CSendQueuesPtr = unique_ptr<CSendQueue[]>;
	using CGCThread		 = CGCThreadT<CUdpServer>;

	friend class CGCThreadT<CUdpServer>;

public:
	virtual BOOL Start	(LPCTSTR lpszBindAddress, USHORT usPort);
	virtual BOOL Stop	();
	virtual BOOL Send	(CONNID dwConnID, const BYTE* pBuffer, int iLength, int iOffset = 0);
	virtual BOOL SendPackets	(CONNID dwConnID, const WSABUF pBuffers[], int iCount);
	virtual BOOL PauseReceive	(CONNID dwConnID, BOOL bPause = TRUE);
	virtual BOOL Wait			(DWORD dwMilliseconds = INFINITE) {return m_evWait.WaitFor(dwMilliseconds, WAIT_FOR_STOP_PREDICATE);}
	virtual BOOL			HasStarted					()	{return m_enState == SS_STARTED || m_enState == SS_STARTING;}
	virtual EnServiceState	GetState					()	{return m_enState;}
	virtual BOOL			Disconnect					(CONNID dwConnID, BOOL bForce = TRUE);
	virtual BOOL			DisconnectLongConnections	(DWORD dwPeriod, BOOL bForce = TRUE);
	virtual BOOL			DisconnectSilenceConnections(DWORD dwPeriod, BOOL bForce = TRUE);
	virtual BOOL			GetListenAddress			(TCHAR lpszAddress[], int& iAddressLen, USHORT& usPort);
	virtual BOOL			GetLocalAddress				(CONNID dwConnID, TCHAR lpszAddress[], int& iAddressLen, USHORT& usPort);
	virtual BOOL			GetRemoteAddress			(CONNID dwConnID, TCHAR lpszAddress[], int& iAddressLen, USHORT& usPort);

	virtual BOOL IsConnected			(CONNID dwConnID);
	virtual BOOL IsPauseReceive			(CONNID dwConnID, BOOL& bPaused);
	virtual BOOL GetPendingDataLength	(CONNID dwConnID, int& iPending);
	virtual DWORD GetConnectionCount	();
	virtual BOOL GetAllConnectionIDs	(CONNID pIDs[], DWORD& dwCount);
	virtual BOOL GetConnectPeriod		(CONNID dwConnID, DWORD& dwPeriod);
	virtual BOOL GetSilencePeriod		(CONNID dwConnID, DWORD& dwPeriod);
	virtual EnSocketError GetLastError	()	{return m_enLastError;}
	virtual LPCTSTR GetLastErrorDesc	()	{return ::GetSocketErrorDesc(m_enLastError);}

private:
	virtual BOOL OnBeforeProcessIo(const TDispContext* pContext, PVOID pv, UINT events)			override;
	virtual VOID OnAfterProcessIo(const TDispContext* pContext, PVOID pv, UINT events, BOOL rs)	override;
	virtual VOID OnCommand(const TDispContext* pContext, TDispCommand* pCmd)					override;
	virtual BOOL OnReadyRead(const TDispContext* pContext, PVOID pv, UINT events)				override;
	virtual BOOL OnReadyWrite(const TDispContext* pContext, PVOID pv, UINT events)				override;
	virtual BOOL OnHungUp(const TDispContext* pContext, PVOID pv, UINT events)					override;
	virtual BOOL OnError(const TDispContext* pContext, PVOID pv, UINT events)					override;
	virtual VOID OnDispatchThreadStart(THR_ID tid)												override;
	virtual VOID OnDispatchThreadEnd(THR_ID tid)												override;

public:
	virtual BOOL IsSecure					() {return FALSE;}

	virtual BOOL SetConnectionExtra(CONNID dwConnID, PVOID pExtra);
	virtual BOOL GetConnectionExtra(CONNID dwConnID, PVOID* ppExtra);

	virtual void SetReuseAddressPolicy		(EnReuseAddressPolicy enReusePolicy)	{ENSURE_HAS_STOPPED(); ASSERT(m_enReusePolicy == enReusePolicy);}
	virtual void SetSendPolicy				(EnSendPolicy enSendPolicy)				{ENSURE_HAS_STOPPED(); ASSERT(m_enSendPolicy == enSendPolicy);}
	virtual void SetOnSendSyncPolicy		(EnOnSendSyncPolicy enOnSendSyncPolicy)	{ENSURE_HAS_STOPPED(); ASSERT(m_enOnSendSyncPolicy == enOnSendSyncPolicy);}
	virtual void SetMaxConnectionCount		(DWORD dwMaxConnectionCount)	{ENSURE_HAS_STOPPED(); m_dwMaxConnectionCount		= dwMaxConnectionCount;}
	virtual void SetWorkerThreadCount		(DWORD dwWorkerThreadCount)		{ENSURE_HAS_STOPPED(); m_dwWorkerThreadCount		= dwWorkerThreadCount;}
	virtual void SetFreeSocketObjLockTime	(DWORD dwFreeSocketObjLockTime)	{ENSURE_HAS_STOPPED(); m_dwFreeSocketObjLockTime	= dwFreeSocketObjLockTime;}
	virtual void SetFreeSocketObjPool		(DWORD dwFreeSocketObjPool)		{ENSURE_HAS_STOPPED(); m_dwFreeSocketObjPool		= dwFreeSocketObjPool;}
	virtual void SetFreeBufferObjPool		(DWORD dwFreeBufferObjPool)		{ENSURE_HAS_STOPPED(); m_dwFreeBufferObjPool		= dwFreeBufferObjPool;}
	virtual void SetFreeSocketObjHold		(DWORD dwFreeSocketObjHold)		{ENSURE_HAS_STOPPED(); m_dwFreeSocketObjHold		= dwFreeSocketObjHold;}
	virtual void SetFreeBufferObjHold		(DWORD dwFreeBufferObjHold)		{ENSURE_HAS_STOPPED(); m_dwFreeBufferObjHold		= dwFreeBufferObjHold;}
	virtual void SetMaxDatagramSize			(DWORD dwMaxDatagramSize)		{ENSURE_HAS_STOPPED(); m_dwMaxDatagramSize			= dwMaxDatagramSize;}
	virtual void SetPostReceiveCount		(DWORD dwPostReceiveCount)		{ENSURE_HAS_STOPPED(); m_dwPostReceiveCount			= dwPostReceiveCount;}
	virtual void SetDetectAttempts			(DWORD dwDetectAttempts)		{ENSURE_HAS_STOPPED(); m_dwDetectAttempts			= dwDetectAttempts;}
	virtual void SetDetectInterval			(DWORD dwDetectInterval)		{ENSURE_HAS_STOPPED(); m_dwDetectInterval			= dwDetectInterval;}
	virtual void SetMarkSilence				(BOOL bMarkSilence)				{ENSURE_HAS_STOPPED(); m_bMarkSilence				= bMarkSilence;}
	virtual void SetDualStack				(BOOL bDualStack)				{ENSURE_HAS_STOPPED(); m_bDualStack					= bDualStack;}

	virtual EnReuseAddressPolicy GetReuseAddressPolicy	()	{return m_enReusePolicy;}
	virtual EnSendPolicy GetSendPolicy					()	{return m_enSendPolicy;}
	virtual EnOnSendSyncPolicy GetOnSendSyncPolicy		()	{return m_enOnSendSyncPolicy;}
	virtual DWORD GetMaxConnectionCount		()	{return m_dwMaxConnectionCount;}
	virtual DWORD GetWorkerThreadCount		()	{return m_dwWorkerThreadCount;}
	virtual DWORD GetFreeSocketObjLockTime	()	{return m_dwFreeSocketObjLockTime;}
	virtual DWORD GetFreeSocketObjPool		()	{return m_dwFreeSocketObjPool;}
	virtual DWORD GetFreeBufferObjPool		()	{return m_dwFreeBufferObjPool;}
	virtual DWORD GetFreeSocketObjHold		()	{return m_dwFreeSocketObjHold;}
	virtual DWORD GetFreeBufferObjHold		()	{return m_dwFreeBufferObjHold;}
	virtual DWORD GetMaxDatagramSize		()	{return m_dwMaxDatagramSize;}
	virtual DWORD GetPostReceiveCount		()	{return m_dwPostReceiveCount;}
	virtual DWORD GetDetectAttempts			()	{return m_dwDetectAttempts;}
	virtual DWORD GetDetectInterval			()	{return m_dwDetectInterval;}
	virtual BOOL  IsMarkSilence				()	{return m_bMarkSilence;}
	virtual BOOL IsDualStack				()	{return m_bDualStack;}

protected:
	virtual EnHandleResult FirePrepareListen(SOCKET soListen)
		{return DoFirePrepareListen(soListen);}
	virtual EnHandleResult FireAccept(TUdpSocketObj* pSocketObj)
		{
			EnHandleResult rs		= DoFireAccept(pSocketObj);
			if(rs != HR_ERROR) rs	= FireHandShake(pSocketObj);
			return rs;
		}
	virtual EnHandleResult FireHandShake(TUdpSocketObj* pSocketObj)
		{return DoFireHandShake(pSocketObj);}
	virtual EnHandleResult FireReceive(TUdpSocketObj* pSocketObj, const BYTE* pData, int iLength)
		{return DoFireReceive(pSocketObj, pData, iLength);}
	virtual EnHandleResult FireReceive(TUdpSocketObj* pSocketObj, int iLength)
		{return DoFireReceive(pSocketObj, iLength);}
	virtual EnHandleResult FireSend(TUdpSocketObj* pSocketObj, const BYTE* pData, int iLength)
		{return DoFireSend(pSocketObj, pData, iLength);}
	virtual EnHandleResult FireClose(TUdpSocketObj* pSocketObj, EnSocketOperation enOperation, int iErrorCode)
		{return DoFireClose(pSocketObj, enOperation, iErrorCode);}
	virtual EnHandleResult FireShutdown()
		{return DoFireShutdown();}

	virtual EnHandleResult DoFirePrepareListen(SOCKET soListen)
		{return m_pListener->OnPrepareListen(this, soListen);}
	virtual EnHandleResult DoFireAccept(TUdpSocketObj* pSocketObj)
		{return m_pListener->OnAccept(this, pSocketObj->connID, (UINT_PTR)(&pSocketObj->remoteAddr));}
	virtual EnHandleResult DoFireHandShake(TUdpSocketObj* pSocketObj)
		{return m_pListener->OnHandShake(this, pSocketObj->connID);}
	virtual EnHandleResult DoFireReceive(TUdpSocketObj* pSocketObj, const BYTE* pData, int iLength)
		{return m_pListener->OnReceive(this, pSocketObj->connID, pData, iLength);}
	virtual EnHandleResult DoFireReceive(TUdpSocketObj* pSocketObj, int iLength)
		{return m_pListener->OnReceive(this, pSocketObj->connID, iLength);}
	virtual EnHandleResult DoFireSend(TUdpSocketObj* pSocketObj, const BYTE* pData, int iLength)
		{return m_pListener->OnSend(this, pSocketObj->connID, pData, iLength);}
	virtual EnHandleResult DoFireClose(TUdpSocketObj* pSocketObj, EnSocketOperation enOperation, int iErrorCode)
		{return m_pListener->OnClose(this, pSocketObj->connID, enOperation, iErrorCode);}
	virtual EnHandleResult DoFireShutdown()
		{return m_pListener->OnShutdown(this);}

	void SetLastError(EnSocketError code, LPCSTR func, int ec);
	virtual BOOL CheckParams();
	virtual void PrepareStart();
	virtual void Reset();

	virtual void OnWorkerThreadStart(THR_ID tid)	{}
	virtual void OnWorkerThreadEnd(THR_ID tid)		{}

	virtual void ReleaseGCSocketObj(BOOL bForce = FALSE);

	TUdpSocketObj*	FindSocketObj(CONNID dwConnID);
	int				SendInternal(TUdpSocketObj* pSocketObj, TItemPtr& itPtr);

	BOOL DoSend(TUdpSocketObj* pSocketObj, const BYTE* pBuffer, int iLength, int iOffset = 0);

protected:
	BOOL SetConnectionExtra(TUdpSocketObj* pSocketObj, PVOID pExtra);
	BOOL GetConnectionExtra(TUdpSocketObj* pSocketObj, PVOID* ppExtra);
	BOOL SetConnectionReserved(CONNID dwConnID, PVOID pReserved);
	BOOL GetConnectionReserved(CONNID dwConnID, PVOID* ppReserved);
	BOOL SetConnectionReserved(TUdpSocketObj* pSocketObj, PVOID pReserved);
	BOOL GetConnectionReserved(TUdpSocketObj* pSocketObj, PVOID* ppReserved);
	BOOL SetConnectionReserved2(CONNID dwConnID, PVOID pReserved2);
	BOOL GetConnectionReserved2(CONNID dwConnID, PVOID* ppReserved2);
	BOOL SetConnectionReserved2(TUdpSocketObj* pSocketObj, PVOID pReserved2);
	BOOL GetConnectionReserved2(TUdpSocketObj* pSocketObj, PVOID* ppReserved2);

private:
	BOOL CheckStarting();
	BOOL CheckStoping();
	BOOL CreateListenSocket(LPCTSTR lpszBindAddress, USHORT usPort);
	BOOL CreateWorkerThreads();
	BOOL StartAccept();

	void SendCloseNotify();
	void CloseListenSocket();
	void DisconnectClientSocket();
	void WaitForClientSocketClose();
	void ReleaseClientSocket();
	void ReleaseFreeSocket();
	void ClearSendQueues();
	void WaitForWorkerThreadEnd();

	TUdpSocketObj* GetFreeSocketObj(CONNID dwConnID);
	TUdpSocketObj* CreateSocketObj();
	CONNID FindConnectionID(const HP_SOCKADDR* pAddr);
	void AddFreeSocketObj(TUdpSocketObj* pSocketObj, EnSocketCloseFlag enFlag = SCF_NONE, EnSocketOperation enOperation = SO_UNKNOWN, int iErrorCode = 0, BOOL bNotify = TRUE);
	void DeleteSocketObj(TUdpSocketObj* pSocketObj);
	BOOL InvalidSocketObj(TUdpSocketObj* pSocketObj);
	void AddClientSocketObj(int idx, CONNID dwConnID, TUdpSocketObj* pSocketObj, const HP_SOCKADDR& remoteAddr);
	void CloseClientSocketObj(TUdpSocketObj* pSocketObj, EnSocketCloseFlag enFlag = SCF_NONE, EnSocketOperation enOperation = SO_UNKNOWN, int iErrorCode = 0, BOOL bNotify = TRUE);

	EnHandleResult TriggerFireAccept(TUdpSocketObj* pSocketObj);

private:
	VOID HandleCmdSend		(CONNID dwConnID, int flag);
	VOID HandleCmdDisconnect(CONNID dwConnID, BOOL bForce);
	VOID HandleCmdTimeout	(CONNID dwConnID);

	CONNID HandleAccept		(const TDispContext* pContext, HP_SOCKADDR& addr);
	BOOL HandleReceive		(const TDispContext* pContext, int flag = 0);
	BOOL HandleSend			(const TDispContext* pContext, int flag = 0);
	BOOL HandleClose		(TUdpSocketObj* pSocketObj, EnSocketOperation enOperation, int iErrorCode);
	void HandleZeroBytes	(TUdpSocketObj* pSocketObj);

	BOOL SendItem			(TUdpSocketObj* pSocketObj, TItem* pItem, BOOL& bBlocked);

	void DetectConnection		(PVOID pv);
	BOOL IsNeedDetectConnection	() const {return m_dwDetectAttempts > 0 && m_dwDetectInterval > 0;}

public:
	CUdpServer(IUdpServerListener* pListener)
	: m_pListener				(pListener)
	, m_enLastError				(SE_OK)
	, m_enState					(SS_STOPPED)
	, m_enSendPolicy			(SP_PACK)
	, m_enOnSendSyncPolicy		(OSSP_RECEIVE)
	, m_enReusePolicy			(RAP_ADDR_AND_PORT)
	, m_dwMaxConnectionCount	(DEFAULT_CONNECTION_COUNT)
	, m_dwWorkerThreadCount		(DEFAULT_WORKER_THREAD_COUNT)
	, m_dwFreeSocketObjLockTime	(DEFAULT_FREE_SOCKETOBJ_LOCK_TIME)
	, m_dwFreeSocketObjPool		(DEFAULT_FREE_SOCKETOBJ_POOL)
	, m_dwFreeBufferObjPool		(DEFAULT_FREE_BUFFEROBJ_POOL)
	, m_dwFreeSocketObjHold		(DEFAULT_FREE_SOCKETOBJ_HOLD)
	, m_dwFreeBufferObjHold		(DEFAULT_FREE_BUFFEROBJ_HOLD)
	, m_dwMaxDatagramSize		(DEFAULT_UDP_MAX_DATAGRAM_SIZE)
	, m_dwPostReceiveCount		(DEFAULT_UDP_POST_RECEIVE_COUNT)
	, m_dwDetectAttempts		(DEFAULT_UDP_DETECT_ATTEMPTS)
	, m_dwDetectInterval		(DEFAULT_UDP_DETECT_INTERVAL)
	, m_bMarkSilence			(TRUE)
	, m_bDualStack				(TRUE)
	, m_thGC					(this)
	{
		ASSERT(m_pListener);
	}

	virtual ~CUdpServer()
	{
		ENSURE_STOP();
	}

private:
	EnReuseAddressPolicy m_enReusePolicy;
	EnSendPolicy m_enSendPolicy;
	EnOnSendSyncPolicy m_enOnSendSyncPolicy;
	DWORD m_dwMaxConnectionCount;
	DWORD m_dwWorkerThreadCount;
	DWORD m_dwFreeSocketObjLockTime;
	DWORD m_dwFreeSocketObjPool;
	DWORD m_dwFreeBufferObjPool;
	DWORD m_dwFreeSocketObjHold;
	DWORD m_dwFreeBufferObjHold;
	DWORD m_dwMaxDatagramSize;
	DWORD m_dwPostReceiveCount;
	DWORD m_dwDetectAttempts;
	DWORD m_dwDetectInterval;
	BOOL  m_bMarkSilence;
	BOOL  m_bDualStack;

protected:
	CBufferObjPool			m_bfObjPool;

private:
	CSEM					m_evWait;

	IUdpServerListener*		m_pListener;
	ListenSocketsPtr		m_soListens;
	EnServiceState			m_enState;
	EnSocketError			m_enLastError;

	CReceiveBuffersPtr		m_rcBuffers;

	CPrivateHeap			m_phSocket;

	CSpinGuard				m_csState;

	CGCThread				m_thGC;

	TUdpSocketObjPtrPool	m_bfActiveSockets;

	CSimpleRWLock			m_csClientSocket;
	TSockAddrMap			m_mpClientAddr;

	TUdpSocketObjPtrList	m_lsFreeSocket;
	TUdpSocketObjPtrQueue	m_lsGCSocket;

	CSendQueuesPtr			m_quSends;

	CIODispatcher			m_ioDispatcher;
};

#endif