/*
	quakeio.c

	(description)

	Copyright (C) 1996-1997  Id Software, Inc.
	Copyright (C) 1999,2000  contributors of the QuakeForge project
	Please see the file "AUTHORS" for a list of contributors

	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

*/
static const char rcsid[] = 
	"$Id$";

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#ifdef HAVE_ZLIB
# include <zlib.h>
#endif
#ifdef HAVE_STRING_H
# include <string.h>
#endif
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif
#ifdef HAVE_IO_H
# include <io.h>
#else
# include <pwd.h>
#endif
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#ifdef _MSC_VER
# define _POSIX_
#endif

#include <limits.h>
#include <stdarg.h>
#include <stdlib.h>

#include "QF/dstring.h"
#include "QF/qendian.h"
#include "QF/quakefs.h"
#include "QF/quakeio.h"

#ifdef WIN32
# ifndef __BORLANDC__
#  define setmode _setmode
#  define O_BINARY _O_BINARY
# endif
#endif

struct QFile_s {
	FILE *file;
#ifdef HAVE_ZLIB
	gzFile *gzfile;
#endif
	off_t size;
};


void
Qexpand_squiggle (const char *path, char *dest)
{
	char       *home;

#ifndef _WIN32
	struct passwd *pwd_ent;
#endif

	if (strncmp (path, "~/", 2) != 0) {
		strcpy (dest, path);
		return;
	}

#ifdef _WIN32
	// LordHavoc: first check HOME to duplicate previous version behavior
	// (also handy if someone wants it elsewhere than their windows directory)
	home = getenv ("HOME");
	if (!home || !home[0])
		home = getenv ("WINDIR");
#else
	if ((pwd_ent = getpwuid (getuid ()))) {
		home = pwd_ent->pw_dir;
	} else
		home = getenv ("HOME");
#endif

	if (home) {
		strcpy (dest, home);
		strncat (dest, path + 1, MAX_OSPATH - strlen (dest));
		// skip leading ~
	} else
		strcpy (dest, path);
}

int
Qrename (const char *old, const char *new)
{
	char        e_old[PATH_MAX];
	char        e_new[PATH_MAX];

	Qexpand_squiggle (old, e_old);
	Qexpand_squiggle (new, e_new);
	return rename (e_old, e_new);
}

int
Qfilesize (QFile *file)
{
	return file->size;
}

QFile *
Qopen (const char *path, const char *mode)
{
	QFile      *file;
	char        m[80], *p;
	int         reading = 0;
	int         zip = 0;
	int         size = -1;
	char        e_path[PATH_MAX];

	Qexpand_squiggle (path, e_path);
	path = e_path;

	for (p = m; *mode && p - m < (sizeof (m) - 1); mode++) {
		if (*mode == 'z') {
			zip = 1;
			continue;
		}
		if (*mode == 'r') {
			reading = 1;
		}
#ifndef HAVE_ZLIB
		if (strchr ("0123456789fh", *mode)) {
			continue;
		}
#endif
		*p++ = *mode;
	}
	*p = 0;

	if (reading) {
		int         fd = open (path, O_RDONLY);
		if (fd != -1) {
			size = lseek (fd, 0, SEEK_END);
			lseek (fd, 0, SEEK_SET);
#ifdef HAVE_ZLIB
			if (zip) {
				byte        id[2];

				read (fd, id, 2);
				if (id[0] == 0x1f && id[1] == 0x8b) {
					lseek (fd, -4, SEEK_END);
					read (fd, &size, 4);
					size = LittleLong (size);
				}
				lseek (fd, 0, SEEK_SET);
			}
#endif
			close (fd);
		}
	}

	file = calloc (sizeof (*file), 1);
	if (!file)
		return 0;
	file->size = size;
#ifdef HAVE_ZLIB
	if (zip) {
		file->gzfile = gzopen (path, m);
		if (!file->gzfile) {
			free (file);
			return 0;
		}
	} else
#endif
	{
		file->file = fopen (path, m);
		if (!file->file) {
			free (file);
			return 0;
		}
	}
	return file;
}

QFile *
Qdopen (int fd, const char *mode)
{
	QFile      *file;
	char        m[80], *p;
	int         zip = 0;

	for (p = m; *mode && p - m < (sizeof (m) - 1); mode++) {
		if (*mode == 'z') {
			zip = 1;
			continue;
		}
		*p++ = *mode;
	}

	*p = 0;

	file = calloc (sizeof (*file), 1);
	if (!file)
		return 0;
#ifdef HAVE_ZLIB
	if (zip) {
		file->gzfile = gzdopen (fd, m);
		if (!file->gzfile) {
			free (file);
			return 0;
		}
	} else
#endif
	{
		file->file = fdopen (fd, m);
		if (!file->file) {
			free (file);
			return 0;
		}
	}
#ifdef WIN32
	if (file->file)
		setmode (_fileno (file->file), O_BINARY);
#endif
	return file;
}

void
Qclose (QFile *file)
{
	if (file->file)
		fclose (file->file);
#ifdef HAVE_ZLIB
	else
		gzclose (file->gzfile);
#endif
	free (file);
}

int
Qread (QFile *file, void *buf, int count)
{
	if (file->file)
		return fread (buf, 1, count, file->file);
#ifdef HAVE_ZLIB
	else
		return gzread (file->gzfile, buf, count);
#else
	return -1;
#endif
}

int
Qwrite (QFile *file, const void *buf, int count)
{
	if (file->file)
		return fwrite (buf, 1, count, file->file);
#ifdef HAVE_ZLIB
	else
		return gzwrite (file->gzfile, (const voidp)buf, count);
#else
	return -1;
#endif
}

int
Qprintf (QFile *file, const char *fmt, ...)
{
	va_list     args;
	int         ret = -1;

	va_start (args, fmt);
	if (file->file)
		ret = vfprintf (file->file, fmt, args);
#ifdef HAVE_ZLIB
	else {
		static dstring_t *buf;

		if (!buf)
			buf = dstring_new ();

		va_start (args, fmt);
		dvsprintf (buf, fmt, args);
		va_end (args);
		ret = strlen (buf->str);
		if (ret > 0)
			ret = gzwrite (file->gzfile, buf, (unsigned) ret);
	}
#endif
	va_end (args);
	return ret;
}

int
Qputs (QFile *file, const char *buf)
{
	if (file->file)
		return fputs (buf, file->file);
#ifdef HAVE_ZLIB
	else
		return gzputs (file->gzfile, buf);
#else
	return 0;
#endif
}

char *
Qgets (QFile *file, char *buf, int count)
{
	if (file->file)
		return fgets (buf, count, file->file);
#ifdef HAVE_ZLIB
	else
		return gzgets (file->gzfile, buf, count);
#else
	return 0;
#endif
}

int
Qgetc (QFile *file)
{
	if (file->file)
		return fgetc (file->file);
#ifdef HAVE_ZLIB
	else
		return gzgetc (file->gzfile);
#else
	return -1;
#endif
}

int
Qputc (QFile *file, int c)
{
	if (file->file)
		return fputc (c, file->file);
#ifdef HAVE_ZLIB
	else
		return gzputc (file->gzfile, c);
#else
	return -1;
#endif
}

int
Qseek (QFile *file, long offset, int whence)
{
	if (file->file)
		return fseek (file->file, offset, whence);
#ifdef HAVE_ZLIB
	else
		return gzseek (file->gzfile, offset, whence);
#else
	return -1;
#endif
}

long
Qtell (QFile *file)
{
	if (file->file)
		return ftell (file->file);
#ifdef HAVE_ZLIB
	else
		return gztell (file->gzfile);
#else
	return -1;
#endif
}

int
Qflush (QFile *file)
{
	if (file->file)
		return fflush (file->file);
#ifdef HAVE_ZLIB
	else
		return gzflush (file->gzfile, Z_SYNC_FLUSH);
#else
	return -1;
#endif
}

int
Qeof (QFile *file)
{
	if (file->file)
		return feof (file->file);
#ifdef HAVE_ZLIB
	else
		return gzeof (file->gzfile);
#else
	return -1;
#endif
}

/*
	Qgetline

	Dynamic length version of Qgets. DO NOT free the buffer.
*/
const char *
Qgetline (QFile *file)
{
	static int  size = 256;
	static char *buf = 0;
	int         len;

	if (!buf) {
		buf = malloc (size);
		if (!buf)
			return 0;
	}

	if (!Qgets (file, buf, size))
		return 0;

	len = strlen (buf);
	while (buf[len - 1] != '\n') {
		char       *t = realloc (buf, size + 256);

		if (!t)
			return 0;
		buf = t;
		size += 256;
		if (!Qgets (file, buf + len, size - len))
			break;
		len = strlen (buf);
	}
	return buf;
}

int
Qgetpos (QFile *file, fpos_t * pos)
{
#ifdef HAVE_FPOS_T_STRUCT
	pos->__pos = Qtell (file);
	return pos->__pos == -1 ? -1 : 0;
#else
	*pos = Qtell (file);
	return *pos == -1 ? -1 : 0;
#endif
}

int
Qsetpos (QFile *file, fpos_t * pos)
{
#ifdef HAVE_FPOS_T_STRUCT
	return Qseek (file, pos->__pos, 0);
#else
	return Qseek (file, *pos, 0);
#endif
}