#include <stdio.h>

 #include <unistd.h>

 #include <dlfcn.h>

 #include <fcntl.h>

 #include <math.h>

 #include "gdc.h"

 #include "GameConfigs.h"

 #include "MemoryUtils.h"

 MemoryUtils mu;

 char *game = NULL;

 char *engine = NULL;

 char *game_binary = NULL;

 char *engine_binary = NULL;

 char *wgame_binary = NULL;

 char *wengine_binary = NULL;

 int main(int argc, char **argv)

 {

 	char *gamedata = NULL;

 	bool debug = false;

 	opterr = 0;

 	int opt;

 	while ((opt = getopt(argc, argv, "b:de:f:g:x:w:y:")) != -1)

 		switch (opt)

 		{

 			case 'd':

 				debug = true;

 				break;

 			case 'g':

 				game = optarg;

 				break;

 			case 'e':

 				engine = optarg;

 				break;

 			case 'f':

 				gamedata = optarg;

 				break;

 			case 'b':

 				game_binary = optarg;

 				break;

 			case 'x':

 				engine_binary = optarg;

 				break;

 			case 'w':

 				wgame_binary = optarg;

 				break;

 			case 'y':

 				wengine_binary = optarg;

 				break;

 			case '?':

 				printf("Usage: ./gdc -g <game> -e <engine name> -f <gamedata file> -b <game binary> -x <engine binary> -w <win game binary> -y <win engine binary>\n");

 				return 0;

 			default:

 				printf("WHAT\n");

 				return 0;

 		}

 	if (!game || !engine || !gamedata || !game_binary || !engine_binary || !wgame_binary || !wengine_binary)

 	{

 		printf("Usage: ./gdc -g <game> -e <engine name> -f <gamedata file> -b <game binary> -x <engine binary> -w <win game binary> -y <win engine binary>\n");

 		return 0;

 	}

 	printf("Game: %s\n", game);

 	if (debug)

 	{

 		printf("Engine: %s\nGame binary: %s\nEngine binary: %s\nWin game binary: %s\nWin engine binary: %s\n",

 			engine, game_binary, engine_binary, wgame_binary, wengine_binary

 			);

 	}

 	printf("Gamedata: %s\n\n", gamedata);

 	void *ghandle;

 	ghandle = dlopen(game_binary, RTLD_LAZY);

 	if (!ghandle)

 	{

 		printf("Couldn't open %s (%s)\n", game_binary, dlerror());

 			return 0;

 	}

 	void *ehandle;

 	ehandle = dlopen(engine_binary, RTLD_LAZY);

 	if (!ehandle)

 	{

 		printf("Couldn't open %s (%s)\n", engine_binary, dlerror());

 			return 0;

 	}

 	int wgfile = open(wgame_binary, O_RDONLY);

 	if (wgfile == -1)

 	{

 		printf("Couldn't open %s\n", wgame_binary);

 		return 0;

 	}

 	int wefile = open(wengine_binary, O_RDONLY);

 	if (wefile == -1)

 	{

 		printf("Couldn't open %s\n", wengine_binary);

 		return 0;

 	}

 	CGameConfig gc;

 	char err[512];

 	if (!gc.EnterFile(gamedata, err, sizeof(err)))

 	{

 		printf("%s: %s\n", gamedata, err);

 		return 0;

 	}

 	CGameConfig symbols;

 	if (!symbols.EnterFile("symbols.txt", err, sizeof(err)))

 	{

 		printf("symbols.txt: %s\n", err);

 		return 0;

 	}

 	const char *vtsym = symbols.GetKeyValue("vtsym");

 	if (!vtsym)

 	{

 		printf("Couldn't find vtsym\n");

 		return 0;

 	}

 	void **vt = (void**) mu.ResolveSymbol(ghandle, vtsym);

 	if (!vt)

 	{

 		printf("Couldn't find vtable %s\n", vtsym);

 		dlclose(ghandle);

 		dlclose(ehandle);

 		close(wgfile);

 		close(wefile);

 		return 0;

 	}

 	for (list<Offset>::iterator it = gc.m_Offsets.begin(); it != gc.m_Offsets.end(); it++)

 	{

 		if (debug)

 		{

 			printf("DEBUG %s - l: %d w: %d\n", it->name, it->lin, it->win);

 		}

 		const char *symbol = symbols.GetKeyValue(it->name);

 		if (symbol)

 		{

 			int newOffset;

 			char symvt[128];

 			strcpy(symvt, it->name);

 			strcat(symvt, "_vt");

 			const char *newvtsym = symbols.GetKeyValue(symvt);

 			if (newvtsym && newvtsym[0])

 			{

 				void **newvt = (void**) mu.ResolveSymbol(ghandle, newvtsym);

 			        if (!newvt)

 				{

 					printf("O: %-22s - can't find, skipping\n", symvt);

 					continue;

 				}

 				newOffset = findVFunc(ghandle, newvt, symbol);

 			}

 			else

 			{

 				newOffset = findVFunc(ghandle, vt, symbol);

 			}

 			if (newOffset == it->lin)

 			{

 				printf("O: %-22s - GOOD.    current [ w: %3d, l: %3d ].\n", it->name, it->win, it->lin);

 			}

 			else

 			{

 				printf("O: %-22s - CHANGED. old [ w: %3d, l: %3d ]. new [ w: %3d, l: %3d ].\n",

 					it->name,

 					it->win, it->lin,

 					newOffset - (it->lin - it->win), newOffset

 					);

 			}

 		}

 		else // !symbol

 		{

 			printf("O: %-22s - no Linux symbol, skipping\n", it->name);

 		}

 	}

 	printf("\nWindows offsets are (semi-)wild guesses!\n\n");

 	for (list<Sig>::iterator it = gc.m_Sigs.begin(); it != gc.m_Sigs.end(); it++)

 	{

 		if (debug)

 		{

 			printf("DEBUG %s - %s - l: %s\n", it->name, it->lib == Server ? "server" : "engine", it->lin);

 		}

 		const char *linSymbol = it->lin;

 		const char *winSymbol = it->win;

 		bool hasLinux   = (linSymbol && linSymbol[0]);

 		bool hasWindows = (winSymbol && winSymbol[0]);

 		if (!hasLinux && !hasWindows)

 		{

 			printf("S: %-22s - hasn't linux nor windows data, skipping\n", it->name);

 			continue;

 		}

 		int  winFile;

 		void *linHandle;

 		if (it->lib == Server)

 		{

 			winFile   = wgfile;

 			linHandle = ghandle;

 		}

 		else if (it->lib == Engine)

 		{

 			winFile   = wefile;

 			linHandle = ehandle;

 		}

 		else

 		{

 			printf("S: %-22s - isn't from server nor engine, skipping\n", it->name);

 			continue;

 		}

 		bool foundLinux   = (!hasLinux   || checkSigStringL(linHandle, linSymbol));

 		bool foundWindows = (!hasWindows || checkSigStringW(winFile,   winSymbol));

 		// Prepare for ternery ABUSE

 		if (foundLinux && foundWindows)

 		{

 			// too much clutter to print current data if it matches anyway, unlike with offsets

 			/*

 			printf("%-22s (%s) - GOOD. current:\n\t[w:%s]\n\t[l:%s]\n",

 				it->name,

 				(it->lib == Server) ? "server" : "engine",

 				winSymbol ? winSymbol : "",

 				linSymbol ? linSymbol : ""

 				);

 			*/

 			printf("S: %-22s (%s) - GOOD.\n",

 				it->name,

 				(it->lib == Server) ? "server" : "engine"

 				);

 		}

 		else

 		{

 			// extra \n at end is intentional to add buffer after possibly long sigs

 			printf("S: %-22s (%s) - w: %s - l: %s\n%s%s%s%s%s%s%s%s\n",

 					it->name,

 					(it->lib == Server) ? "server" : "engine",

 					hasWindows ? (foundWindows ? "GOOD" : "CHANGED") : "UNKNOWN",

 					hasLinux   ? (foundLinux   ? "GOOD" : "CHANGED") : "UNKNOWN",

 					hasWindows ? "\tcurrent - w: " : "",

 					(hasWindows && foundWindows) ? "    (found) \"" : (hasWindows ? "(NOT found) \"" : ""),

 					(hasWindows && winSymbol)  ? winSymbol : "",

 					hasWindows ? "\"\n" : "",

 					hasLinux ? "\tcurrent - l: " : "",

 					(hasLinux && foundLinux) ? "    (found) \"" : (hasLinux ? "(NOT found) \"" : ""),

 					(hasLinux && linSymbol)  ? linSymbol : "",

 					hasLinux ? "\"\n" : ""

 					);

 		}

 		//  j/k, no way that anyone could have been prepared for that

 	}

 	return 0;

 }

 bool checkSigStringW(int file, const char* symbol)

 {

 	void *addr = NULL;

 	bool isAt = (symbol[0] == '@');

 	// we can't support this on windows from here

 	if (isAt)

 		return false;

 	unsigned char real_sig[511];

 	size_t real_bytes = UTIL_DecodeHexString(real_sig, sizeof(real_sig), symbol);

 	if (real_bytes >= 1)

 	{

 		addr = mu.FindPatternInFile(file, (char*)real_sig, real_bytes);

 	}

 	if (addr)

 		return true;

 	return false;

 }

 bool checkSigStringL(void *handle, const char* symbol)

 {

 	void *addr = NULL;

 	bool isAt = (symbol[0] == '@');

 	if (isAt)

 	{

 		addr = mu.ResolveSymbol(handle, symbol + 1);

 	}

 	else

 	{

 		unsigned char real_sig[511];

 		size_t real_bytes = UTIL_DecodeHexString(real_sig, sizeof(real_sig), symbol);

 		if (real_bytes >= 1)

 		{

 			addr = mu.FindPattern(handle, (char*)real_sig, real_bytes);

 		}

 	}

 	if (addr)

 		return true;

 	return false;

 }

 /* 

    takes a mangled member function symbol and returns the position where the function name and parameters start

    01234567890123456789012345678

    _ZN9CTFPlayer12ForceRespawnEv

                 ^13            ^28

 */

 void findFuncPos(const char *sym, int &func, int &params)

 {

 	int i = 0;

 	while ((sym[i] < '0') || (sym[i] > '9')) i++;

 	int classLen = atoi(sym + i);

 	func = i + (int)ceil(log10(classLen)) + classLen;

 	int funcLen = atoi(sym + func);

 	params = func + (int)ceil(log10(funcLen)) + funcLen;

 }

 int findVFunc(void *handle, void **vt, const char *symbol)

 {

 	int offset = 1;

 	int funcPos, paramPos;

 	findFuncPos(symbol, funcPos, paramPos);

 	for (int i = 0; i < 1000; i++)

 	{

 		void *pFunc = vt[i];

 		const char *s;

 		if (!(s = mu.ResolveAddr(handle, pFunc)))

 			continue;

 		if ((i > 1) && (strncmp(s, "_ZTI", 4) == 0))

 			break;

 		int tempFuncPos, tempParamPos;

 		findFuncPos(s, tempFuncPos, tempParamPos);

 		if (strcmp(s + tempFuncPos, symbol + funcPos) == 0)

 		{

 			offset = i;

 			break;

 		}

 	}

 	return offset - 2;

 }

 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);

 }

 size_t UTIL_Format(char *buffer, size_t maxlength, const char *fmt, ...)

 {

 	va_list ap;

 	va_start(ap, fmt);

 	size_t len = vsnprintf(buffer, maxlength, fmt, ap);

 	va_end(ap);

 	if (len >= maxlength)

 	{

 		buffer[maxlength - 1] = '\0';

 		return (maxlength - 1);

 	}

 	else

 	{

 		return len;

 	}

 }

 size_t UTIL_DecodeHexString(unsigned char *buffer, size_t maxlength, const char *hexstr)

 {

 	size_t written = 0;

 	size_t length = strlen(hexstr);

 	for (size_t i = 0; i < length; i++)

 	{

 		if (written >= maxlength)

 			break;

 		buffer[written++] = hexstr[i];

 		if (hexstr[i] == '\\' && hexstr[i + 1] == 'x')

 		{

 			if (i + 3 >= length)

 				continue;

 			/* Get the hex part. */

 			char s_byte[3];

 			int r_byte;

 			s_byte[0] = hexstr[i + 2];

 			s_byte[1] = hexstr[i + 3];

 			s_byte[2] = '\0';

 			/* Read it as an integer */

 			sscanf(s_byte, "%x", &r_byte);

 			/* Save the value */

 			buffer[written - 1] = r_byte;

 			/* Adjust index */

 			i += 3;

 		}

 	}

 	return written;

 }