/*==LICENSE==*

CyanWorlds.com Engine - MMOG client, server and tools
Copyright (C) 2011 Cyan Worlds, Inc.

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 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 General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.

Additional permissions under GNU GPL version 3 section 7

If you modify this Program, or any covered work, by linking or
combining it with any of RAD Game Tools Bink SDK, Autodesk 3ds Max SDK,
NVIDIA PhysX SDK, Microsoft DirectX SDK, OpenSSL library, Independent
JPEG Group JPEG library, Microsoft Windows Media SDK, or Apple QuickTime SDK
(or a modified version of those libraries),
containing parts covered by the terms of the Bink SDK EULA, 3ds Max EULA,
PhysX SDK EULA, DirectX SDK EULA, OpenSSL and SSLeay licenses, IJG
JPEG Library README, Windows Media SDK EULA, or QuickTime SDK EULA, the
licensors of this Program grant you additional
permission to convey the resulting work. Corresponding Source for a
non-source form of such a combination shall include the source code for
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work.

You can contact Cyan Worlds, Inc. by email legal@cyan.com
 or by snail mail at:
      Cyan Worlds, Inc.
      14617 N Newport Hwy
      Mead, WA   99021

*==LICENSE==*/
/*****************************************************************************
*
*   $/Plasma20/Sources/Plasma/NucleusLib/pnOraLib/pnOraLib.cpp
*   
***/

#include "Pch.h"
#pragma hdrstop


//#define ORACONN_TRACKING
//#define ORASTMT_TRACKING

#ifdef ORACONN_TRACKING
#pragma message("pnOraLib: Compiling with ORACONN_TRACKING")
#endif
#ifdef ORASTMT_TRACKING
#pragma message("pnOraLib: Compiling with ORASTMT_TRACKING")
#endif


/*****************************************************************************
*
*   Private
*
***/

struct OraInitData {
	unsigned	OraStmtCacheSize;
	wchar		OraUsername[128]; 
	wchar		OraPassword[128]; 
	wchar		OraConnectString[256];
	
	OraInitData(
		unsigned	stmtCacheSize, 
		const wchar username[], 
		const wchar password[], 
		const wchar connectString[] 
	);
};

struct OraEnv {
	occi::Environment *				occiEnv;
	occi::StatelessConnectionPool *	occiPool;
};

struct OraConnPool {
	bool				needReinit;
	long				perf[kOcciNumPerf];
	CCritSect			critsect;
	OraEnv				oraEnv;
	OraInitData *		data;

	void Initialize_CS ();
	void Shutdown_CS ();
	void ReInitialize_CS ();	
	
	void Initialize (
		const wchar username[], 
		const wchar password[], 
		const wchar connectString[],
		unsigned	stmtCacheSize
	);
	void Shutdown ();
	OraConn * GetConn (const wchar tag[]);
	void FreeConn (OraConn *& conn);
	
	long GetPerf (long index);
};


/*****************************************************************************
*
*   Private Data
*
***/

static const unsigned kDefaultConnTimeoutSecs	= 60 * 30;		// half-hour
static const unsigned kDefaultConnsPerEnv		= 10;

enum {
	kPerfOraConnCount,
	kPerfOraStmtCount,
	kNumPerf
};

static OraConnPool	s_connPool;
static long			s_perf[kNumPerf];


/*****************************************************************************
*
*   Local functions
*
***/

/*****************************************************************************
*
*   OraInitData
*
***/

//============================================================================
OraInitData::OraInitData (
	unsigned	stmtCacheSize, 
	const wchar username[], 
	const wchar password[], 
	const wchar connectString[] 
) {
	OraStmtCacheSize = stmtCacheSize;
	StrCopy(OraUsername, username, arrsize(OraUsername));
	StrCopy(OraPassword, password, arrsize(OraPassword));
	StrCopy(OraConnectString, connectString, arrsize(OraConnectString));
}


/*****************************************************************************
*
*   OraConnPool
*
***/

//============================================================================
void OraConnPool::ReInitialize_CS () {

	Shutdown_CS();
	Initialize_CS();
	
	needReinit = false;
}

//============================================================================
void OraConnPool::Initialize_CS () {

	ASSERT(data);
	
	try {
		const unsigned threads = AsyncThreadTaskGetThreadCount();
		const unsigned maxConns = threads;
		const unsigned minConns = 0;
		const unsigned incConns = max(1, maxConns - 1);
		
		// Some memory allocated by createEnvironment is leaked,
		// so we disable memory tracking while calling it.
		MemPushDisableTracking();
		oraEnv.occiEnv = occi::Environment::createEnvironment(
			"OCCIUTF16",
			"OCCIUTF16",
			occi::Environment::THREADED_MUTEXED,
			nil
		);
		MemPopDisableTracking();

		// Create the connection pool		
		oraEnv.occiPool = oraEnv.occiEnv->createStatelessConnectionPool(
			data->OraUsername,
			data->OraPassword,
			data->OraConnectString,
			maxConns,
			minConns,
			incConns,
			occi::StatelessConnectionPool::HOMOGENEOUS
		);
		
		// Turn on statement caching
		oraEnv.occiPool->setStmtCacheSize(data->OraStmtCacheSize);
		oraEnv.occiPool->setTimeOut(kDefaultConnTimeoutSecs);
		// If no connections are available, block until one becomes available
		oraEnv.occiPool->setBusyOption(occi::StatelessConnectionPool::WAIT);
	}
	catch (exception & e) {
		OraLogError(L"OraConnPool::Initialize", e);
		ErrorFatal(__LINE__, __FILE__, "Failed to initialize occi connection pool");
	}
}

//============================================================================
void OraConnPool::Shutdown_CS () {

	if (oraEnv.occiEnv) {
		try {
			// If we aren't connected to oracle, then closing the connection
			// pool causes oracle to make a pure virtual function call when
			// closing the environment.
			if (!needReinit)
				oraEnv.occiEnv->terminateStatelessConnectionPool(oraEnv.occiPool, occi::StatelessConnectionPool::SPD_FORCE);
			occi::Environment::terminateEnvironment(oraEnv.occiEnv);
		}
		catch (exception & e) {
			OraLogError(L"OraConnPool::Shutdown", e);
		}
		oraEnv.occiEnv = nil;
		oraEnv.occiPool = nil;
	}
}

//============================================================================
void OraConnPool::Initialize (
	const wchar username[], 
	const wchar password[], 
	const wchar connectString[],
	unsigned	stmtCacheSize
) {
	data = NEW(OraInitData)(stmtCacheSize, username, password, connectString);

	critsect.Enter();
	{
		Initialize_CS();
	}
	critsect.Leave();
}

//============================================================================
void OraConnPool::Shutdown () {

	critsect.Enter();
	{
		Shutdown_CS();
	}
	critsect.Leave();

	DEL(data);
}

//============================================================================
OraConn * OraConnPool::GetConn (const wchar tag[]) {

	OraConn * oraConn = NEWZERO(OraConn);
	if (tag)
		StrCopy(oraConn->tag, tag, arrsize(oraConn->tag));

	critsect.Enter();
	for (;;) try {
		if (needReinit) {
			if (GetPerf(kOcciPerfBusyConns))
				// Wait for all connections to be freed by the app
				// before environment reinitialization.
				break;

			ReInitialize_CS();
		}
			
		if (!oraEnv.occiEnv)
			break;
			
		if (nil != (oraConn->occiConn = oraEnv.occiPool->getConnection()))
			oraConn->oraEnv = &oraEnv;

		break;
	}
	catch (exception & e) {
		OraLogError(L"OraConnPool::GetConn", e);
		oraConn = nil; 
        break;  
	}
	critsect.Leave();

	for (;;) {	
		if (!oraConn || !oraConn->occiConn) {
			DEL(oraConn);
			oraConn = nil;
			LogMsg(kLogError, L"OraConnPool::GetConn: Failed to aquire a database connection");
			break;
		}

		const unsigned connCount = AtomicAdd(&s_perf[kPerfOraConnCount], 1) + 1;
		ref(connCount);

	#ifdef ORACONN_TRACKING
		LogMsg(kLogPerf, L"OraGetConn: %u, %p, %s", connCount, oraConn, oraConn->tag);
	#endif
	
		break;
	}
		
	return oraConn;
}

//============================================================================
void OraConnPool::FreeConn (OraConn *& oraConn) {

	if (oraConn) try {
		occi::Connection * occiConn = oraConn->occiConn;
		occi::StatelessConnectionPool * occiPool = oraConn->oraEnv->occiPool;
		
		const unsigned connCount = AtomicAdd(&s_perf[kPerfOraConnCount], -1) - 1;
		ref(connCount);

#ifdef ORACONN_TRACKING
		LogMsg(kLogPerf, L"OraFreeConn: %u, %p, %s", connCount, oraConn, oraConn->tag);
#endif

		DEL(oraConn);

		try {
			occiConn->commit();
		}
		catch (exception & e) {
			OraLogError(L"OraConnPool::FreeConn [commit]", e);
			needReinit = true;
		}

		occiPool->releaseConnection(occiConn);
	}
	catch (exception & e) {
		OraLogError(L"OraConnPool::FreeConn [release]", e);
	}

	oraConn = nil;
}

//============================================================================
long OraConnPool::GetPerf (long index) {

	if (!oraEnv.occiEnv)
		return 0;
	if (!oraEnv.occiPool)
		return 0;

	switch (index) {
		case kOcciPerfOpenConns: return oraEnv.occiPool->getOpenConnections();
		case kOcciPerfBusyConns: return oraEnv.occiPool->getBusyConnections();
		DEFAULT_FATAL(index);
	}
}


/*****************************************************************************
*
*   Exports
*
***/

//============================================================================
void OraLogError (const wchar sql[], const exception & e) {

	wchar buffer[1024];
	const char * tmp = e.what();
	
	// Some exceptions we catch are actually unicode strings in a char buffer, but others aren't.
	if (tmp[0] && !tmp[1]) {
		const wchar * wtmp = (const wchar *)tmp;
		StrCopy(buffer, wtmp, arrsize(buffer));
	}
	else {
		StrToUnicode(buffer, tmp, arrsize(buffer));
	}
	LogMsg(kLogError, L"%s, %s", sql, buffer);
}

//============================================================================
void OraGetShaDigest (
	occi::Statement *	oraStmt,
	unsigned			index,
	ShaDigest *			digest
) {
	occi::Bytes bytes = oraStmt->getBytes(index);
	const unsigned length = bytes.length();
	ASSERT(length == msizeof(ShaDigest, data));
	bytes.getBytes((byte *)digest->data, length);
}

//============================================================================
void OraSetShaDigest (
	occi::Statement *		oraStmt,
	unsigned				index,
	const ShaDigest &		digest
) {
	occi::Bytes bytes((byte *)&digest, sizeof(digest));
	oraStmt->setBytes(index, bytes);
}

//============================================================================
void OraBindString (
	occi::Statement *	oraStmt,
	unsigned			index,
	wchar *				buffer,
	unsigned			chars,
	ub2 *				length,
	sb2 *				indicator
) {
	oraStmt->setDataBuffer(
		index,
		buffer,
		occi::OCCI_SQLT_STR,
		chars * sizeof(buffer[0]),
		length,
		indicator
	);
}

//============================================================================
void OraBindString (
	occi::ResultSet *	rs,
	unsigned			index,
	wchar *				buffer,
	unsigned			chars,
	ub2 *				length,
	sb2 *				indicator
) {
	rs->setDataBuffer(
		index,
		buffer,
		occi::OCCI_SQLT_STR,
		chars * sizeof(buffer[0]),
		length,
		indicator
	);
}

//============================================================================
void OraGetUuid (
	occi::Statement *	oraStmt,
	unsigned			index,
	Uuid *				uuid
) {
	occi::Bytes bytes = oraStmt->getBytes(index);
	if (const unsigned length = bytes.length()) {
		ASSERT(length == msizeof(Uuid, data));
		byte * buf = ALLOCA(byte, length);
		bytes.getBytes(buf, length);
		GuidFromHex(buf, length, uuid);
	}
	else {
		GuidClear(uuid);
	}
}

//============================================================================
void OraSetUuid (
	occi::Statement *	oraStmt,
	unsigned			index,
	const Uuid &		uuid
) {
	occi::Bytes bytes((byte *)&uuid, sizeof(uuid));
	oraStmt->setBytes(index, bytes);
}

//============================================================================
OraConn * OraGetConn (const wchar tag[]) {
	
	// grabs a cached connection if available, otherwise creates a new one on-the-fly
	return s_connPool.GetConn(tag);
}

//============================================================================
void OraFreeConn (OraConn *& oraConn) {

	s_connPool.FreeConn(oraConn);
}

//============================================================================
occi::Statement * OraGetStmt (
	OraConn *		oraConn,
	const wchar		sql[]
) {
	occi::Statement * oraStmt = nil;
	try {
		// grabs a matching cached statement if available, otherwise creates a new one
		oraStmt = oraConn->occiConn->createStatement(sql);
		// auto-commit causes an exception to be thrown when writing blobs: "ORA-01002: fetch out of sequence"
		oraStmt->setAutoCommit(false);

		const unsigned stmtCount = AtomicAdd(&s_perf[kPerfOraStmtCount], 1) + 1;
		ref(stmtCount);
		
		#ifdef ORASTMT_TRACKING
		LogMsg(kLogPerf, L"OraGetStmt: %u, %p, %s", stmtCount, oraStmt, sql);
		#endif
	}
	catch (exception & e) {
		OraLogError(L"OraGetStmt", e);
	}
	return oraStmt;
}

//============================================================================
 void OraFreeStmt (occi::Statement *& oraStmt) {
	if (oraStmt) {
		try {
			// caches the statement
			oraStmt->getConnection()->terminateStatement(oraStmt);

			const unsigned stmtCount = AtomicAdd(&s_perf[kPerfOraStmtCount], -1) - 1;
			ref(stmtCount);

			#ifdef ORASTMT_TRACKING
			LogMsg(kLogPerf, L"OraFreeStmt: %u, %p", stmtCount, oraStmt);
			#endif
		}
		catch (exception & e) {
			OraLogError(L"OraFreeStmt", e);
		}
		oraStmt = nil;
	}
}

//============================================================================
void OraInitialize (	
	const wchar username[], 
	const wchar password[], 
	const wchar connectString[],
	unsigned	stmtCacheSize
) {
	// Connect to the database
	s_connPool.Initialize(
		username,
		password,
		connectString,
		stmtCacheSize
	);
}

//============================================================================
void OraShutdown () {

}

//============================================================================
void OraDestroy () {
	s_connPool.Shutdown();
}

//============================================================================
long OraLibGetOcciPerf (unsigned index) {
	return s_connPool.GetPerf(index);
}