/**

  * vim: set ts=4 :

  * =============================================================================

  * SourceMod SQLite Extension

  * Copyright (C) 2004-2008 AlliedModders LLC.  All rights reserved.

  * =============================================================================

  *

  * This program is free software; you can redistribute it and/or modify it under

  * the terms of the GNU General Public License, version 3.0, as published by the

  * Free Software Foundation.

  * 

  * 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/>.

  *

  * As a special exception, AlliedModders LLC gives you permission to link the

  * code of this program (as well as its derivative works) to "Half-Life 2," the

  * "Source Engine," the "SourcePawn JIT," and any Game MODs that run on software

  * by the Valve Corporation.  You must obey the GNU General Public License in

  * all respects for all other code used.  Additionally, AlliedModders LLC grants

  * this exception to all derivative works.  AlliedModders LLC defines further

  * exceptions, found in LICENSE.txt (as of this writing, version JULY-31-2007),

  * or <http://www.sourcemod.net/license.php>.

  *

  * Version: $Id$

  */

 #include <sm_platform.h>

 #include "extension.h"

 #include "SqDriver.h"

 #include "SqDatabase.h"

 SqDriver g_SqDriver;

 unsigned int strncopy(char *dest, const char *src, size_t count)

 {

 	if (!count)

 	{

 		return 0;

 	}

 	char *start = dest;

 	while ((*src) && (--count))

 	{

 		*dest++ = *src++;

 	}

 	*dest = '\0';

 	return (dest - start);

 }

 int busy_handler(void *unused1, int unused2)

 {

 #if defined PLATFORM_WINDOWS

 	Sleep(100);

 #elif defined PLATFORM_LINUX

 	usleep(100000);

 #endif

 	return 1;

 }

 SqDriver::SqDriver()

 {

 	m_Handle = BAD_HANDLE;

 	m_pOpenLock = NULL;

 	m_bThreadSafe = false;

 }

 void SqDriver::Initialize()

 {

 	m_pOpenLock = threader->MakeMutex();

 	InitializeThreadSafety();

 }

 void SqDriver::Shutdown()

 {

 	if (m_pOpenLock)

 	{

 		m_pOpenLock->DestroyThis();

 	}

 	if (m_bThreadSafe)

 	{

 		sqlite3_enable_shared_cache(0);

 	}

 }

 bool SqDriver::IsThreadSafe()

 {

 	return true;

 }

 bool SqDriver::InitializeThreadSafety()

 {

 	if (m_bThreadSafe)

 	{

 		return true;

 	}

 	if (sqlite3_threadsafe() == 0)

 	{

 		return false;

 	}

 	if (sqlite3_enable_shared_cache(1) != SQLITE_OK)

 	{

 		return false;

 	}

 	m_bThreadSafe = true;

 	return true;

 }

 void SqDriver::ShutdownThreadSafety()

 {

 	return;

 }

 IdentityToken_t *SqDriver::GetIdentity()

 {

 	return myself->GetIdentity();

 }

 const char *SqDriver::GetProductName()

 {

 	return "SQLite";

 }

 const char *SqDriver::GetIdentifier()

 {

 	return "sqlite";

 }

 Handle_t SqDriver::GetHandle()

 {

 	if (m_Handle == BAD_HANDLE)

 	{

 		m_Handle = dbi->CreateHandle(DBHandle_Driver, this, myself->GetIdentity());

 	}

 	return m_Handle;

 }

 inline bool IsPathSepChar(char c)

 {

 #if defined PLATFORM_WINDOWS

 	return (c == '\\' || c == '/');

 #elif defined PLATFORM_LINUX

 	return (c == '/');

 #endif

 }

 IDatabase *SqDriver::Connect(const DatabaseInfo *info, bool persistent, char *error, size_t maxlength)

 {

 	/* We wrap most of the open process in a mutex just to be safe */

 	m_pOpenLock->Lock();

 	/* Format our path */

 	char path[PLATFORM_MAX_PATH];

 	size_t len = libsys->PathFormat(path, sizeof(path), "sqlite/%s", info->database);

 	/* Chop any filename off */

 	for (size_t i = len-1;

 		 i >= 0 && i <= len-1;

 		 i--)

 	{

 		if (IsPathSepChar(path[i]))

 		{

 			path[i] = '\0';

 			break;

 		}

 	}

 	/* Test the full path */

 	char fullpath[PLATFORM_MAX_PATH];

 	g_pSM->BuildPath(Path_SM, fullpath, sizeof(fullpath), "data/%s", path);

 	if (!libsys->IsPathDirectory(fullpath))

 	{

 		/* Make sure the data folder exists */

 		len = g_pSM->BuildPath(Path_SM, fullpath, sizeof(fullpath), "data");

 		if (!libsys->IsPathDirectory(fullpath))

 		{

 			if (!libsys->CreateFolder(fullpath))

 			{

 				strncopy(error, "Could not create or open \"data\" folder\"", maxlength);

 				m_pOpenLock->Unlock();

 				return NULL;

 			}

 		}

 		/* The data folder exists - create each subdir as needed! */

 		char *cur_ptr = path;

 		do

 		{

 			/* Find the next suitable path */

 			char *next_ptr = cur_ptr;

 			while (*next_ptr != '\0')

 			{

 				if (IsPathSepChar(*next_ptr))

 				{

 					*next_ptr = '\0';

 					next_ptr++;

 					break;

 				}

 				next_ptr++;

 			}

 			if (*next_ptr == '\0')

 			{

 				next_ptr = NULL;

 			}

 			len += libsys->PathFormat(&fullpath[len], sizeof(fullpath)-len, "/%s", cur_ptr);

 			if (!libsys->IsPathDirectory(fullpath) && !libsys->CreateFolder(fullpath))

 			{

 				break;

 			}

 			cur_ptr = next_ptr;

 		} while (cur_ptr);

 	}

 	/* Build the FINAL path. */

 	g_pSM->BuildPath(Path_SM, fullpath, sizeof(fullpath), "data/sqlite/%s.sq3", info->database);

 	/* If we're requesting a persistent connection, see if something is already open */

 	if (persistent)

 	{

 		/* See if anything in the cache matches */

 		List<SqDbInfo>::iterator iter;

 		for (iter = m_Cache.begin(); iter != m_Cache.end(); iter++)

 		{

 			if ((*iter).path.compare(fullpath) == 0)

 			{

 				(*iter).db->IncReferenceCount();

 				m_pOpenLock->Unlock();

 				return (*iter).db;

 			}

 		}

 	}

 	/* Try to open a new connection */

 	sqlite3 *sql;

 	int err = sqlite3_open(fullpath, &sql);

 	if (err != SQLITE_OK)

 	{

 		strncopy(error, sqlite3_errmsg(sql), maxlength);

 		sqlite3_close(sql);

 		m_pOpenLock->Unlock();

 		return NULL;

 	}

 	sqlite3_busy_handler(sql, busy_handler, NULL);

 	SqDatabase *pdb = new SqDatabase(sql, persistent);

 	if (persistent)

 	{

 		SqDbInfo pinfo;

 		pinfo.path = fullpath;

 		pinfo.db = pdb;

 		m_Cache.push_back(pinfo);

 	}

 	m_pOpenLock->Unlock();

 	return pdb;

 }

 void SqDriver::RemovePersistent(IDatabase *pdb)

 {

 	List<SqDbInfo>::iterator iter;

 	for (iter = m_Cache.begin(); iter != m_Cache.end(); iter++)

 	{

 		if ((*iter).db == pdb)

 		{

 			iter = m_Cache.erase(iter);

 			return;

 		}

 	}

 }