/**

 * vim: set ts=4 sw=4 tw=99 noet :

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

 * SourceMod

 * Copyright (C) 2004-2009 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>.

 */

#include <string.h>

#include <stdlib.h>

#include "GameConfigs.h"

#include "sm_stringutil.h"

#include "sourcemod.h"

#include "sourcemm_api.h"

#include "HalfLife2.h"

#include "Logger.h"

#include "ShareSys.h"

#include "MemoryUtils.h"

#include "LibrarySys.h"

#include "HandleSys.h"

#include "sm_crc32.h"

#if defined PLATFORM_LINUX

#include <dlfcn.h>

#endif

GameConfigManager g_GameConfigs;

IGameConfig *g_pGameConf = NULL;

static char g_Game[256];

static char g_GameDesc[256] = {'!', '\0'};

static char g_GameName[256] = {'$', '\0'};

#define PSTATE_NONE						0

#define PSTATE_GAMES					1

#define PSTATE_GAMEDEFS					2

#define PSTATE_GAMEDEFS_OFFSETS			3

#define PSTATE_GAMEDEFS_OFFSETS_OFFSET	4

#define PSTATE_GAMEDEFS_KEYS			5

#define PSTATE_GAMEDEFS_SUPPORTED		6

#define PSTATE_GAMEDEFS_SIGNATURES		7

#define PSTATE_GAMEDEFS_SIGNATURES_SIG	8

#define PSTATE_GAMEDEFS_CRC				9

#define PSTATE_GAMEDEFS_CRC_BINARY		10

#define PSTATE_GAMEDEFS_CUSTOM			11

#if defined PLATFORM_WINDOWS

#define PLATFORM_NAME				"windows"

#define PLATFORM_SERVER_BINARY		"server.dll"

#elif defined PLATFORM_LINUX

#define PLATFORM_NAME				"linux"

#define PLATFORM_SERVER_BINARY		"server_i486.so"

#elif defined PLATFORM_APPLE

#define PLATFORM_NAME               "undef"

#define PLATFORM_SERVER_BINARY      "undef.dylib"

#endif

struct TempSigInfo

{

	void Reset()

	{

		library[0] = '\0';

		sig[0] = '\0';

	}

	char sig[512];

	char library[64];

} s_TempSig;

unsigned int s_ServerBinCRC;

bool s_ServerBinCRC_Ok = false;

static bool DoesGameMatch(const char *value)

{

#if defined PLATFORM_WINDOWS

	if (strcasecmp(value, g_Game) == 0 ||

#else

	if (strcmp(value, g_Game) == 0 ||

#endif

		strcmp(value, g_GameDesc) == 0 ||

		strcmp(value, g_GameName) == 0)

	{

		return true;

	}

	return false;

}

static bool DoesEngineMatch(const char *value)

{

#if SOURCE_ENGINE == SE_EPISODEONE

	if (strcmp(value, "original") == 0)

#elif SOURCE_ENGINE == SE_DARKMESSIAH

	if (strcmp(value, "darkmessiah") == 0)

#elif SOURCE_ENGINE == SE_ORANGEBOX

	if (strcmp(value, "orangebox") == 0)

#elif SOURCE_ENGINE == SE_ORANGEBOXVALVE

	if (strcmp(value, "orangebox_valve") == 0)

#elif SOURCE_ENGINE == SE_LEFT4DEAD

	if (strcmp(value, "left4dead") == 0)

#elif SOURCE_ENGINE == SE_LEFT4DEAD2

	if (strcmp(value, "left4dead2") == 0)

#else

#error "Unknown engine type"

#endif

	{

		return true;

	}

	return false;

}

CGameConfig::CGameConfig(const char *file)

{

	strncopy(m_File, file, sizeof(m_File));

	m_pOffsets = sm_trie_create();

	m_pProps = sm_trie_create();

	m_pKeys = sm_trie_create();

	m_pSigs = sm_trie_create();

	m_pStrings = new BaseStringTable(512);

	m_RefCount = 0;

	m_CustomLevel = 0;

	m_CustomHandler = NULL;

}

CGameConfig::~CGameConfig()

{

	sm_trie_destroy(m_pOffsets);

	sm_trie_destroy(m_pProps);

	sm_trie_destroy(m_pKeys);

	sm_trie_destroy(m_pSigs);

	delete m_pStrings;

}

SMCResult CGameConfig::ReadSMC_NewSection(const SMCStates *states, const char *name)

{

	if (m_IgnoreLevel)

	{

		m_IgnoreLevel++;

		return SMCResult_Continue;

	}

	switch (m_ParseState)

	{

	case PSTATE_NONE:

		{

			if (strcmp(name, "Games") == 0)

			{

				m_ParseState = PSTATE_GAMES;

			} else {

				m_IgnoreLevel++;

			}

			break;

		}

	case PSTATE_GAMES:

		{

			if (strcmp(name, "*") == 0 ||

				strcmp(name, "#default") == 0 ||

				DoesGameMatch(name))

			{

				bShouldBeReadingDefault = true;

				m_ParseState = PSTATE_GAMEDEFS;

				strncopy(m_Game, name, sizeof(m_Game));

			} else {

				m_IgnoreLevel++;

			}

			break;

		}

	case PSTATE_GAMEDEFS:

		{

			if (strcmp(name, "Offsets") == 0)

			{

				m_ParseState = PSTATE_GAMEDEFS_OFFSETS;

			}

			else if (strcmp(name, "Keys") == 0)

			{

				m_ParseState = PSTATE_GAMEDEFS_KEYS;

			}

			else if ((strcmp(name, "#supported") == 0) && (strcmp(m_Game, "#default") == 0))

			{

				m_ParseState = PSTATE_GAMEDEFS_SUPPORTED;

				/* Ignore this section unless we get a game. */

				bShouldBeReadingDefault = false;

				had_game = false;

				matched_game = false;

				had_engine = false;

				matched_engine = false;

			}

			else if (strcmp(name, "Signatures") == 0)

			{

				m_ParseState = PSTATE_GAMEDEFS_SIGNATURES;

			}

			else if (strcmp(name, "CRC") == 0)

			{

				m_ParseState = PSTATE_GAMEDEFS_CRC;

				bShouldBeReadingDefault = false;

			}

			else

			{

				ITextListener_SMC **pListen = g_GameConfigs.m_customHandlers.retrieve(name);

				if (pListen != NULL)

				{

					m_CustomLevel = 0;

					m_ParseState = PSTATE_GAMEDEFS_CUSTOM;

					m_CustomHandler = *pListen;

					m_CustomHandler->ReadSMC_ParseStart();

					break;

				}

				m_IgnoreLevel++;

			}

			break;

		}

	case PSTATE_GAMEDEFS_OFFSETS:

		{

			m_Prop[0] = '\0';

			m_Class[0] = '\0';

			strncopy(m_offset, name, sizeof(m_offset));

			m_ParseState = PSTATE_GAMEDEFS_OFFSETS_OFFSET;

			break;

		}

	case PSTATE_GAMEDEFS_SIGNATURES:

		{

			strncopy(m_offset, name, sizeof(m_offset));

			s_TempSig.Reset();

			m_ParseState = PSTATE_GAMEDEFS_SIGNATURES_SIG;

			break;

		}

	case PSTATE_GAMEDEFS_CRC:

		{

			char error[255];

			error[0] = '\0';

			if (strcmp(name, "server") != 0)

			{

				UTIL_Format(error, sizeof(error), "Unrecognized library \"%s\"", name);

			} 

			else if (!s_ServerBinCRC_Ok)

			{

				FILE *fp;

				char path[PLATFORM_MAX_PATH];

				g_SourceMod.BuildPath(Path_Game, path, sizeof(path), "bin/" PLATFORM_SERVER_BINARY);

				if ((fp = fopen(path, "rb")) == NULL)

				{

					UTIL_Format(error, sizeof(error), "Could not open binary: %s", path);

				} else {

					size_t size;

					void *buffer;

					fseek(fp, 0, SEEK_END);

					size = ftell(fp);

					fseek(fp, 0, SEEK_SET);

					buffer = malloc(size);

					fread(buffer, size, 1, fp);

					s_ServerBinCRC = UTIL_CRC32(buffer, size);

					free(buffer);

					s_ServerBinCRC_Ok = true;

					fclose(fp);

				}

			}

			if (error[0] != '\0')

			{

				m_IgnoreLevel = 1;

				g_Logger.LogError("[SM] Error while parsing CRC section for \"%s\" (%s):", m_Game, m_CurFile);

				g_Logger.LogError("[SM] %s", error);

			} else {

				m_ParseState = PSTATE_GAMEDEFS_CRC_BINARY;

			}

			break;

		}

	case PSTATE_GAMEDEFS_CUSTOM:

		{

			m_CustomLevel++;

			return m_CustomHandler->ReadSMC_NewSection(states, name);

			break;

		}

	/* No sub-sections allowed:

	 case PSTATE_GAMEDEFS_OFFSETS_OFFSET:

	 case PSTATE_GAMEDEFS_KEYS:

	 case PSTATE_GAMEDEFS_SUPPORTED:

	 case PSTATE_GAMEDEFS_SIGNATURES_SIG:

	 case PSTATE_GAMEDEFS_CRC_BINARY:

	 */

	default:

		{

			/* If we don't know what we got, start ignoring */

			m_IgnoreLevel++;

			break;

		}

	}

	return SMCResult_Continue;

}

SMCResult CGameConfig::ReadSMC_KeyValue(const SMCStates *states, const char *key, const char *value)

{

	if (m_IgnoreLevel)

	{

		return SMCResult_Continue;

	}

	if (m_ParseState == PSTATE_GAMEDEFS_OFFSETS_OFFSET)

	{

		if (strcmp(key, "class") == 0)

		{

			strncopy(m_Class, value, sizeof(m_Class));

		} else if (strcmp(key, "prop") == 0) {

			strncopy(m_Prop, value, sizeof(m_Prop));

		} else if (strcmp(key, PLATFORM_NAME) == 0) {

			int val = atoi(value);

			sm_trie_replace(m_pOffsets, m_offset, (void *)val);

		}

	} else if (m_ParseState == PSTATE_GAMEDEFS_KEYS) {

		int id = m_pStrings->AddString(value);

		sm_trie_replace(m_pKeys, key, (void *)id);

	} else if (m_ParseState == PSTATE_GAMEDEFS_SUPPORTED) {

		if (strcmp(key, "game") == 0)

		{

			had_game = true;

			if (DoesGameMatch(value))

			{

				matched_game = true;

			}

			if ((!had_engine && matched_game) || (matched_engine && matched_game))

			{

				bShouldBeReadingDefault = true;

			}

		}

		else if (strcmp(key, "engine") == 0)

		{

			had_engine = true;

			if (DoesEngineMatch(value))

			{

				matched_engine = true;

			}

			if ((!had_game && matched_engine) || (matched_game && matched_engine))

			{

				bShouldBeReadingDefault = true;

			}

		}

	} else if (m_ParseState == PSTATE_GAMEDEFS_SIGNATURES_SIG) {

		if (strcmp(key, PLATFORM_NAME) == 0)

		{

			strncopy(s_TempSig.sig, value, sizeof(s_TempSig.sig));

		} else if (strcmp(key, "library") == 0) {

			strncopy(s_TempSig.library, value, sizeof(s_TempSig.library));

		}

	} else if (m_ParseState == PSTATE_GAMEDEFS_CRC_BINARY) {

		if (strcmp(key, PLATFORM_NAME) == 0 

			&& s_ServerBinCRC_Ok

			&& !bShouldBeReadingDefault)

		{

			unsigned int crc = 0;

			sscanf(value, "%08X", &crc);

			if (s_ServerBinCRC == crc)

			{

				bShouldBeReadingDefault = true;

			}

		}

	} else if (m_ParseState == PSTATE_GAMEDEFS_CUSTOM) {

		return m_CustomHandler->ReadSMC_KeyValue(states, key, value);

	}

	return SMCResult_Continue;

}

SMCResult CGameConfig::ReadSMC_LeavingSection(const SMCStates *states)

{

	if (m_IgnoreLevel)

	{

		m_IgnoreLevel--;

		return SMCResult_Continue;

	}

	if (m_CustomLevel)

	{

		m_CustomLevel--;

		m_CustomHandler->ReadSMC_LeavingSection(states);

		return SMCResult_Continue;

	}

	switch (m_ParseState)

	{

	case PSTATE_GAMES:

		{

			m_ParseState = PSTATE_NONE;

			break;

		}

	case PSTATE_GAMEDEFS:

		{

			m_ParseState = PSTATE_GAMES;

			break;

		}

	case PSTATE_GAMEDEFS_CUSTOM:

		{

			m_ParseState = PSTATE_GAMEDEFS;

			m_CustomHandler->ReadSMC_ParseEnd(false, false);

			break;

		}

	case PSTATE_GAMEDEFS_KEYS:

	case PSTATE_GAMEDEFS_OFFSETS:

		{

			m_ParseState = PSTATE_GAMEDEFS;

			break;

		}

	case PSTATE_GAMEDEFS_OFFSETS_OFFSET:

		{

			/* Parse the offset... */

			if (m_Class[0] != '\0'

				&& m_Prop[0] != '\0')

			{

				SendProp *pProp = g_HL2.FindInSendTable(m_Class, m_Prop);

				if (pProp)

				{

					int val = pProp->GetOffset();

					sm_trie_replace(m_pOffsets, m_offset, (void *)val);

					sm_trie_replace(m_pProps, m_offset, pProp);

				} else {

					/* Check if it's a non-default game and no offsets exist */

					if (((strcmp(m_Game, "*") != 0) && strcmp(m_Game, "#default") != 0)

						&& (!sm_trie_retrieve(m_pOffsets, m_offset, NULL)))

					{

						g_Logger.LogError("[SM] Unable to find property %s.%s (file \"%s\") (mod \"%s\")", 

							m_Class,

							m_Prop,

							m_CurFile,

							m_Game);

					}

				}

			}

			m_ParseState = PSTATE_GAMEDEFS_OFFSETS;

			break;

		}

	case PSTATE_GAMEDEFS_CRC:

	case PSTATE_GAMEDEFS_SUPPORTED:

		{

			if (!bShouldBeReadingDefault)

			{

				/* If we shouldn't read the rest of this section, set the ignore level. */

				m_IgnoreLevel = 1;

				m_ParseState = PSTATE_GAMES;

			} else {

				m_ParseState = PSTATE_GAMEDEFS;

			}

			break;

		}

	case PSTATE_GAMEDEFS_CRC_BINARY:

		{

			m_ParseState = PSTATE_GAMEDEFS_CRC;

			break;

		}

	case PSTATE_GAMEDEFS_SIGNATURES:

		{

			m_ParseState = PSTATE_GAMEDEFS;

			break;

		}

	case PSTATE_GAMEDEFS_SIGNATURES_SIG:

		{

			if (s_TempSig.library[0] == '\0')

			{

				/* assume server */

				strncopy(s_TempSig.library, "server", sizeof(s_TempSig.library));

			}

			void *addrInBase = NULL;

			if (strcmp(s_TempSig.library, "server") == 0)

			{

				addrInBase = (void *)g_SMAPI->GetServerFactory(false);

			} else if (strcmp(s_TempSig.library, "engine") == 0) {

				addrInBase = (void *)g_SMAPI->GetEngineFactory(false);

			}

			void *final_addr = NULL;

			if (addrInBase == NULL)

			{

				g_Logger.LogError("[SM] Unrecognized library \"%s\" (gameconf \"%s\")", 

					s_TempSig.library, 

					m_CurFile);

			} else {

#if defined PLATFORM_LINUX

				if (s_TempSig.sig[0] == '@')

				{

					Dl_info info;

					/* GNU only: returns 0 on error, inconsistent! >:[ */

					if (dladdr(addrInBase, &info) != 0)

					{

						void *handle = dlopen(info.dli_fname, RTLD_NOW);

						if (handle)

						{

#if SOURCE_ENGINE == SE_LEFT4DEAD2

							final_addr = g_MemUtils.ResolveSymbol(handle, &s_TempSig.sig[1]);

#else

							final_addr = dlsym(handle, &s_TempSig.sig[1]);

#endif

							dlclose(handle);

						} else {

							g_Logger.LogError("[SM] Unable to load library \"%s\" (gameconf \"%s\")",

								s_TempSig.library,

								m_File);

						}

					} else {

						g_Logger.LogError("[SM] Unable to find library \"%s\" in memory (gameconf \"%s\")",

							s_TempSig.library,

							m_File);

					}

				}

				if (final_addr)

				{

					goto skip_find;

				}

#endif

				/* First, preprocess the signature */

				unsigned char real_sig[511];

				size_t real_bytes;

				size_t length;

				real_bytes = 0;

				length = strlen(s_TempSig.sig);

				real_bytes = UTIL_DecodeHexString(real_sig, sizeof(real_sig), s_TempSig.sig);

				if (real_bytes >= 1)

				{

					final_addr = g_MemUtils.FindPattern(addrInBase, (char*)real_sig, real_bytes);

				}

			}

#if defined PLATFORM_LINUX

skip_find:

#endif

			sm_trie_replace(m_pSigs, m_offset, final_addr);

			m_ParseState = PSTATE_GAMEDEFS_SIGNATURES;

			break;

		}

	}

	return SMCResult_Continue;

}

#define MSTATE_NONE		0

#define MSTATE_MAIN		1

#define MSTATE_FILE		2

class MasterReader : public ITextListener_SMC

{

public:

	virtual void ReadSMC_ParseStart()

	{

		state = MSTATE_NONE;

		ignoreLevel = 0;

	}

	virtual SMCResult ReadSMC_NewSection(const SMCStates *states, const char *name)

	{

		if (ignoreLevel)

		{

			return SMCResult_Continue;

		}

		if (state == MSTATE_NONE)

		{

			if (strcmp(name, "Game Master") == 0)

			{

				state = MSTATE_MAIN;

			}

			else

			{

				ignoreLevel++;

			}

		}

		else if (state == MSTATE_MAIN)

		{

			strncopy(cur_file, name, sizeof(cur_file));