/* 
	cmdlib.c

	Command library

	Copyright (C) 1996-1997 id Software, Inc.
	Copyright (C) 2001 Jeff Teunissen <deek@dusknet.dhs.org>

	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 2 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, write to:

		Free Software Foundation, Inc.
		59 Temple Place - Suite 330
		Boston, MA  02111-1307, USA

	$Id$
*/

#include <sys/types.h>
#include <sys/stat.h>

#ifdef __unix__
# ifdef NeXT
#  include <libc.h>
# endif
# include <unistd.h>
#endif

#ifdef WIN32
#include <direct.h>
#endif

#include <QF/sys.h>

#include "cmdlib.h"

#define PATHSEPERATOR   '/'

// set these before calling CheckParm
int 		myargc;
char		**myargv;

char		com_token[1024];
qboolean	com_eof;
qboolean	archive;
char		archivedir[1024];

/*
	Error

	For abnormal program terminations
*/ 
void
Error (char *error, ...) 
{
	va_list argptr;
	
	printf ("************ ERROR ************\n");
	
	va_start (argptr, error);
	vprintf (error, argptr);
	va_end (argptr);
	printf ("\n");
	exit (1);
} 


/*

qdir will hold the path up to the quake directory, including the slash

  f:\quake\
  /raid/quake/

gamedir will hold qdir + the game directory (id1, id2, etc)

*/
char	qdir[1024];
char	gamedir[1024];

void
SetQdirFromPath (char *path)
{
	char	temp[1024];
	char	*c;

	if (!(path[0] == '/' || path[0] == '\\' || path[1] == ':')) {	// partial path
		Q_getwd (temp);
		strcat (temp, path);
		path = temp;
	}

	// search for "quake" in path
	for (c = path; *c; c++) {
		if (!Q_strncasecmp (c, "quake", 5)) {
			strncpy (qdir, path, c + 6 - path);
			printf ("qdir: %s\n", qdir);
			c += 6;
			while (*c) {
				if (*c == '/' || *c == '\\') {
					strncpy (gamedir, path, c + 1 - path);
					printf ("gamedir: %s\n", gamedir);
					return;
				}
				c++;
			}

			Error ("No gamedir in %s", path);
			return;
		}
	}

	Error ("SeetQdirFromPath: no 'quake' in %s", path);
}

char *
ExpandPath (char *path)
{
	static char full[1024];

	if (!qdir)
		Error ("ExpandPath called without qdir set");

	if (path[0] == '/' || path[0] == '\\' || path[1] == ':')
		return path;

	sprintf (full, "%s%s", qdir, path);
	return full;
}

char *
ExpandPathAndArchive (char *path) 
{
	char	*expanded;
	char	archivename[1024];

	expanded = ExpandPath (path);
	
	if (archive) {
		sprintf (archivename, "%s/%s", archivedir, path);
		CopyFile (expanded, archivename);
	}
	return expanded;
}

/*
	I_FloatTime
*/
double
I_FloatTime (void)
{
	time_t	t;

	time (&t);

	return t;
#if 0
	// more precise, less portable
	struct timeval tp;
	struct timezone tzp;
	static int  secbase;

	gettimeofday (&tp, &tzp);

	if (!secbase) {
		secbase = tp.tv_sec;
		return tp.tv_usec / 1000000.0;
	}

	return (tp.tv_sec - secbase) + tp.tv_usec / 1000000.0;
#endif
}

void
Q_getwd (char *out)
{
#ifdef WIN32
	_getcwd (out, 256);
	strcat (out, "\\");
#else
	getcwd (out, 256);
#endif
}

void
Q_mkdir (char *path)
{
#ifdef WIN32
	if (_mkdir (path) != -1)
		return;
#else
	if (mkdir (path, 0777) != -1)
		return;
#endif
	if (errno != EEXIST)
		Error ("mkdir %s: %s", path, strerror (errno));
}

/*
	FileTime

	returns -1 if not present
*/
int
FileTime (char *path)
{
	struct stat buf;

	if (stat (path, &buf) == -1)
		return -1;

	return buf.st_mtime;
}



/*
	COM_Parse

	Parse a token out of a string
*/
char *
COM_Parse (char *data)
{
	int 	c;
	int 	len = 0;

	com_token[0] = 0;

	if (!data)
		return NULL;

	// skip whitespace
skipwhite:
	while ((c = *data) <= ' ') {
		if (c == 0) {
			com_eof = true;
			return NULL;				// end of file;
		}
		data++;
	}

	// skip // comments
	if (c == '/' && data[1] == '/') {
		while (*data && *data != '\n')
			data++;
		goto skipwhite;
	}

	// handle quoted strings specially
	if (c == '\"') {
		data++;
		do {
			c = *data++;
			if (c == '\"') {
				com_token[len] = 0;
				return data;
			}
			com_token[len] = c;
			len++;
		} while (1);
	}

	// parse single characters
	if (c == '{' || c == '}' || c == ')' || c == '(' || c == '\'' || c == ':') {
		com_token[len] = c;
		len++;
		com_token[len] = 0;
		return data + 1;
	}

	// parse a regular word
	do {
		com_token[len] = c;
		data++;
		len++;
		c = *data;
		if (c == '{' || c == '}' || c == ')' || c == '(' || c == '\''
			|| c == ':')
			break;
	} while (c > 32);

	com_token[len] = 0;
	return data;
}


int
Q_strncasecmp (char *s1, char *s2, int n)
{
	int         c1, c2;

	while (1) {
		c1 = *s1++;
		c2 = *s2++;

		if (!n--)
			return 0;					// strings are equal until end point

		if (c1 != c2) {
			if (c1 >= 'a' && c1 <= 'z')
				c1 -= ('a' - 'A');
			if (c2 >= 'a' && c2 <= 'z')
				c2 -= ('a' - 'A');
			if (c1 != c2)
				return -1;				// strings not equal
		}
		if (!c1)
			return 0;					// strings are equal
	}

	return -1;
}

int
Q_strcasecmp (char *s1, char *s2)
{
	return Q_strncasecmp (s1, s2, 99999);
}


char *
strupr (char *start)
{
	char	*in;

	in = start;
	while (*in) {
		*in = toupper (*in);
		in++;
	}
	return start;
}

char *
strlower (char *start)
{
	char	*in;

	in = start;
	while (*in) {
		*in = tolower (*in);
		in++;
	}
	return start;
}


/*
=============================================================================

						MISC FUNCTIONS

=============================================================================
*/


/*
	CheckParm

	Checks for the given parameter in the program's command line arguments
	Returns the argument number (1 to argc-1) or 0 if not present
*/
int
CheckParm (char *check)
{
	int 	i;

	for (i = 1; i < myargc; i++) {
		if (!Q_strcasecmp (check, myargv[i]))
			return i;
	}

	return 0;
}



/*
	filelength
*/
int
filelength (FILE *f)
{
	int 	pos;
	int 	end;

	pos = ftell (f);
	fseek (f, 0, SEEK_END);
	end = ftell (f);
	fseek (f, pos, SEEK_SET);

	return end;
}


FILE *
SafeOpenWrite (char *filename)
{
	FILE	*f;

	f = fopen (filename, "wb");

	if (!f)
		Error ("Error opening %s: %s", filename, strerror (errno));

	return f;
}

FILE *
SafeOpenRead (char *filename)
{
	FILE       *f;

	f = fopen (filename, "rb");

	if (!f)
		Error ("Error opening %s: %s", filename, strerror (errno));

	return f;
}


void
SafeRead (FILE *f, void *buffer, int count)
{
	if (fread (buffer, 1, count, f) != (size_t) count)
		Error ("File read failure");
}


void
SafeWrite (FILE *f, void *buffer, int count)
{
	if (fwrite (buffer, 1, count, f) != (size_t) count)
		Error ("File read failure");
}


/*
	LoadFile
*/
int
LoadFile (char *filename, void **bufferptr)
{
	FILE	*f;
	int 	length;
	void	*buffer;

	f = SafeOpenRead (filename);
	length = filelength (f);
	buffer = malloc (length + 1);
	((char *) buffer)[length] = 0;
	SafeRead (f, buffer, length);
	fclose (f);

	*bufferptr = buffer;
	return length;
}


/*
	SaveFile
*/
void
SaveFile (char *filename, void *buffer, int count)
{
	FILE	*f;

	f = SafeOpenWrite (filename);
	SafeWrite (f, buffer, count);
	fclose (f);
}


/*
	DefaultExtension

	Append an extension if the path doesn't have one.
	The extension passed should include . at the beginning.
*/
void
DefaultExtension (char *path, char *extension)
{
	char	*src;

	src = path + strlen (path) - 1;

	while (*src != PATHSEPERATOR && src != path) {
		if (*src == '.')
			return;						// it has an extension
		src--;
	}

	strcat (path, extension);
}


void
DefaultPath (char *path, char *basepath)
{
	char	temp[128];

	if (path[0] == PATHSEPERATOR)
		return;							// absolute path location
	strcpy (temp, path);
	strcpy (path, basepath);
	strcat (path, temp);
}


void
StripFilename (char *path)
{
	int 	length;

	length = strlen (path) - 1;
	while (length > 0 && path[length] != PATHSEPERATOR)
		length--;
	path[length] = 0;
}

void
StripExtension (char *path)
{
	int 	length;

	length = strlen (path) - 1;
	while (length > 0 && path[length] != '.') {
		length--;
		if (path[length] == PATHSEPERATOR)	// no extension
			return;
	}
	if (length)
		path[length] = 0;
}


/*
====================
Extract file parts
====================
*/
void
ExtractFilePath (char *path, char *dest)
{
	char	*src;

	src = path + strlen (path) - 1;

	// back up until a / or the start
	while (src != path && *(src - 1) != PATHSEPERATOR)
		src--;

	memcpy (dest, path, src - path);
	dest[src - path] = 0;
}

void
ExtractFileBase (char *path, char *dest)
{
	char	*src;

	src = path + strlen (path) - 1;

	// back up until a / or the start
	while (src != path && *(src - 1) != PATHSEPERATOR)
		src--;

	while (*src && *src != '.') {
		*dest++ = *src++;
	}
	*dest = 0;
}

void
ExtractFileExtension (char *path, char *dest)
{
	char	*src;

	src = path + strlen (path) - 1;

	// back up until a . or the start
	while (src != path && *(src - 1) != '.')
		src--;
	if (src == path) {
		*dest = 0;						// no extension
		return;
	}

	strcpy (dest, src);
}


/*
	ParseNum / ParseHex
*/
int
ParseHex (char *hex)
{
	char	*str;
	int 	num;

	num = 0;
	str = hex;

	while (*str) {
		num <<= 4;
		if (*str >= '0' && *str <= '9')
			num += *str - '0';
		else if (*str >= 'a' && *str <= 'f')
			num += 10 + *str - 'a';
		else if (*str >= 'A' && *str <= 'F')
			num += 10 + *str - 'A';
		else
			Error ("Bad hex number: %s", hex);
		str++;
	}

	return num;
}


int
ParseNum (char *str)
{
	if (str[0] == '$')
		return ParseHex (str + 1);
	if (str[0] == '0' && str[1] == 'x')
		return ParseHex (str + 2);
	return atol (str);
}

/*
============================================================================

					BYTE ORDER FUNCTIONS

============================================================================
*/

#ifdef WORDS_BIGENDIAN

short
LittleShort (short l)
{
	byte        b1, b2;

	b1 = l & 255;
	b2 = (l >> 8) & 255;

	return (b1 << 8) + b2;
}

short
BigShort (short l)
{
	return l;
}

int
LittleLong (int l)
{
	byte        b1, b2, b3, b4;

	b1 = l & 255;
	b2 = (l >> 8) & 255;
	b3 = (l >> 16) & 255;
	b4 = (l >> 24) & 255;

	return ((int) b1 << 24) + ((int) b2 << 16) + ((int) b3 << 8) + b4;
}

int
BigLong (int l)
{
	return l;
}


float
LittleFloat (float l)
{
	union {
		byte	b[4];
		float	f;
	} in, out;

	in.f = l;
	out.b[0] = in.b[3];
	out.b[1] = in.b[2];
	out.b[2] = in.b[1];
	out.b[3] = in.b[0];

	return out.f;
}

float
BigFloat (float l)
{
	return l;
}

#else


short
BigShort (short l)
{
	byte	b1, b2;

	b1 = l & 255;
	b2 = (l >> 8) & 255;

	return (b1 << 8) + b2;
}

short
LittleShort (short l)
{
	return l;
}


int
BigLong (int l)
{
	byte	b1, b2, b3, b4;

	b1 = l & 255;
	b2 = (l >> 8) & 255;
	b3 = (l >> 16) & 255;
	b4 = (l >> 24) & 255;

	return ((int) b1 << 24) + ((int) b2 << 16) + ((int) b3 << 8) + b4;
}

int
LittleLong (int l)
{
	return l;
}

float
BigFloat (float l)
{
	union {
		byte	b[4];
		float	f;
	} in, out;

	in.f = l;
	out.b[0] = in.b[3];
	out.b[1] = in.b[2];
	out.b[2] = in.b[1];
	out.b[3] = in.b[0];

	return out.f;
}

float
LittleFloat (float l)
{
	return l;
}


#endif


//=======================================================
	

// FIXME: byte swap?
	
// this is a 16 bit, non-reflected CRC using the polynomial 0x1021
// and the initial and final xor values shown below...  in other words, the
// CCITT standard CRC used by XMODEM
	
#define CRC_INIT_VALUE	0xffff
#define CRC_XOR_VALUE	0x0000
static unsigned short crctable[256] = {
	0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7, 0x8108,
	0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef, 0x1231, 0x0210,
	0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6, 0x9339, 0x8318, 0xb37b,
	0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de, 0x2462, 0x3443, 0x0420, 0x1401,
	0x64e6, 0x74c7, 0x44a4, 0x5485, 0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee,
	0xf5cf, 0xc5ac, 0xd58d, 0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6,
	0x5695, 0x46b4, 0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d,
	0xc7bc, 0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823,
	0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b, 0x5af5,
	0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12, 0xdbfd, 0xcbdc,
	0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a, 0x6ca6, 0x7c87, 0x4ce4,
	0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41, 0xedae, 0xfd8f, 0xcdec, 0xddcd,
	0xad2a, 0xbd0b, 0x8d68, 0x9d49, 0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13,
	0x2e32, 0x1e51, 0x0e70, 0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a,
	0x9f59, 0x8f78, 0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e,
	0xe16f, 0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
	0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e, 0x02b1,
	0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256, 0xb5ea, 0xa5cb,
	0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d, 0x34e2, 0x24c3, 0x14a0,
	0x0481, 0x7466, 0x6447, 0x5424, 0x4405, 0xa7db, 0xb7fa, 0x8799, 0x97b8,
	0xe75f, 0xf77e, 0xc71d, 0xd73c, 0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657,
	0x7676, 0x4615, 0x5634, 0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9,
	0xb98a, 0xa9ab, 0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882,
	0x28a3, 0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
	0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92, 0xfd2e,
	0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9, 0x7c26, 0x6c07,
	0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1, 0xef1f, 0xff3e, 0xcf5d,
	0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8, 0x6e17, 0x7e36, 0x4e55, 0x5e74,
	0x2e93, 0x3eb2, 0x0ed1, 0x1ef0
};

void
CRC_Init (unsigned short *crcvalue) 
{
	*crcvalue = CRC_INIT_VALUE;
} 

void
CRC_ProcessByte (unsigned short *crcvalue, byte data) 
{
	*crcvalue = (*crcvalue << 8) ^ crctable[(*crcvalue >> 8) ^ data];
} 

unsigned short
CRC_Value (unsigned short crcvalue) 
{
	return crcvalue ^ CRC_XOR_VALUE;
}


//=============================================================================
	
/*
	CreatePath

	Create a path.
*/ 
void
CreatePath (char *path) 
{
	char	*ofs, c;

	for (ofs = path + 1; *ofs; ofs++) {

		c = *ofs;
		if (c == '/' || c == '\\') {	// create the directory
			*ofs = 0;
			Q_mkdir (path);
			*ofs = c;
		}
	}
}


/*
	CopyFile

	Used to archive source files
*/ 
void
CopyFile (char *from, char *to) 
{
	void	*buffer;
	int 	length;

	length = LoadFile (from, &buffer);
	CreatePath (to);
	SaveFile (to, buffer, length);
	free (buffer);
}