/*
Copyright (C) 1996-1997 Id Software, Inc.

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

*/
// sys_unix.c -- Unix system driver

#include "quakedef.h"
#include "sys.h"
#include "qargs.h"

#include <stdio.h>
#include <errno.h>
#include <fcntl.h>
#include <stddef.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <sys/param.h>

#ifndef MAP_FAILED
# define MAP_FAILED ((void*)-1)
#endif

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#ifdef HAVE_STRINGS_H
#include <strings.h>
#endif

qboolean			isDedicated;

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

FILE IO

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

#define MAX_HANDLES	64	// 1999-12-23 More PAK files support by Maddes

typedef struct
{
	QFile	*hFile;
	char	*pMap;
	int		nLen;
	int		nPos;
} MEMFILE;

MEMFILE	sys_handles[MAX_HANDLES];

int
findhandle ( void )
{
	int	i;

	for (i=1 ; i<MAX_HANDLES ; i++)
		if (!sys_handles[i].hFile)
			return i;
	Sys_Error ("out of handles");
	return -1;
}

/*
================
filelength
================
*/
int
filelength ( QFile *f )
{
	int		pos;
	int		end;

	pos = Qtell (f);
	Qseek (f, 0, SEEK_END);
	end = Qtell (f);
	Qseek (f, pos, SEEK_SET);

	return end;
}

/* from sys_linux.c */
int
Sys_FileOpenRead ( char *path, int *handle )
{
	int	h;
	struct stat	fileinfo;

	h = open (path, O_RDONLY, 0666);
	*handle = h;
	if (h == -1)
		return -1;

	if (fstat (h,&fileinfo) == -1)
		Sys_Error ("Error fstating %s", path);

	return fileinfo.st_size;
}

int
Sys_FileOpenWrite ( char *path )
{
	QFile	*f;
	int		i;

	i = findhandle ();

	f = Qopen(path, "wb");
	if (!f)
		Sys_Error ("Error opening %s: %s", path,strerror(errno));
	sys_handles[i].hFile = f;
	sys_handles[i].nLen = 0;
	sys_handles[i].nPos = 0;
	sys_handles[i].pMap = NULL;

	return i;
}

void
Sys_FileClose ( int handle )
{
	if (sys_handles[handle].pMap)
		if (munmap( sys_handles[handle].pMap, sys_handles[handle].nLen ) != 0)
			printf( "failed to unmap handle %d\n", handle );

	Qclose (sys_handles[handle].hFile);
	sys_handles[handle].hFile = NULL;
}

void
Sys_FileSeek ( int handle, int position )
{
	if (sys_handles[handle].pMap) {
		sys_handles[handle].nPos = position;
	} else {
		Qseek (sys_handles[handle].hFile, position, SEEK_SET);
	}
}

int
Sys_FileRead ( int handle, void *dest, int count )
{
	if (sys_handles[handle].pMap) {
		int nPos = sys_handles[handle].nPos;
		if (count < 0) count = 0;
		if (nPos + count > sys_handles[handle].nLen)
			count = sys_handles[handle].nLen - nPos;
		memcpy( dest, &sys_handles[handle].pMap[nPos], count );
		sys_handles[handle].nPos = nPos + count;
		return( count );
	} else {
		return Qread (sys_handles[handle].hFile, dest, count);
	}
}

int
Sys_FileWrite ( int handle, void *data, int count )
{
	if (sys_handles[handle].pMap)
		Sys_Error( "Attempted to write to read-only file %d!\n", handle );
	return Qwrite (sys_handles[handle].hFile, data, count);
}

void
Sys_DebugLog ( char *file, char *fmt, ... )
{
	va_list argptr;
	static char data[1024];
	QFile *stream;
	unsigned char *p;
	//int fd;

	va_start(argptr, fmt);
	vsnprintf(data, sizeof(data), fmt, argptr);
	va_end(argptr);
//	fd = open(file, O_WRONLY | O_BINARY | O_CREAT | O_APPEND, 0666);
	stream = Qopen(file, "a");
	for (p = (unsigned char *) data; *p; p++) {
		Qputc(stream, trans_table[*p]);
	}
	Qclose(stream);
/*
	fd = open(file, O_WRONLY | O_CREAT | O_APPEND, 0666);
	write(fd, data, strlen(data));
	close(fd);
*/
}


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

SYSTEM IO

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

void
Sys_MakeCodeWriteable ( unsigned long startaddr, unsigned long length )
{

	int r;
	unsigned long addr;
	int psize = getpagesize();

	addr = (startaddr & ~(psize-1)) - psize;

//	fprintf(stderr, "writable code %lx(%lx)-%lx, length=%lx\n", startaddr,
//			addr, startaddr+length, length);

	r = mprotect((char*)addr, length + startaddr - addr + psize, 7);

	if (r < 0)
		Sys_Error("Protection change failed\n");

}


void
Sys_Error ( char *error, ... )
{
	va_list		argptr;

	printf ("Sys_Error: ");
	va_start (argptr,error);
	vprintf (error,argptr);
	va_end (argptr);
	printf ("\n");
	Host_Shutdown();
	exit (1);
}

void
Sys_Quit ( void )
{
	Host_Shutdown();
	exit (0);
}

char *
Sys_ConsoleInput ( void )
{
	static char		text[256];
	int				len;
	fd_set			readfds;
	int				ready;
	struct timeval	timeout;

	timeout.tv_sec = 0;
	timeout.tv_usec = 0;
	FD_ZERO(&readfds);
	FD_SET(0, &readfds);
	ready = select(1, &readfds, 0, 0, &timeout);

	if (ready>0) {
		len = read (0, text, sizeof(text));
		if (len >= 1) {
			text[len-1] = 0;	// rip off the /n and terminate
			return text;
		}
	}

	return 0;
}

void
Sys_Sleep ( void )
{
}

#if !id386
void
Sys_HighFPPrecision ( void )
{
}

void
Sys_LowFPPrecision ( void )
{
}
#endif

void
Sys_Init( void )
{
#if id386
	Sys_SetFPCW();
#endif
}

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

int
main ( int argc, char **argv )
{
	static quakeparms_t	parms;
	float	oldtime, newtime;

	parms.memsize = 16*1024*1024;
	parms.membase = malloc (parms.memsize);
	parms.basedir = ".";
	parms.cachedir = NULL;

	signal(SIGFPE, SIG_IGN);

	COM_InitArgv (argc, argv);

	parms.argc = com_argc;
	parms.argv = com_argv;

	printf ("Host_Init\n");
	Host_Init (&parms);

	Sys_Init();

	// unroll the simulation loop to give the video side a chance to see _vid_default_mode
	Host_Frame( 0.1 );
	// FIXME - probably should be deleted - this is just an empty function
//	VID_SetDefaultMode();

	oldtime = Sys_DoubleTime();
	while (1)
	{
		newtime = Sys_DoubleTime();
		Host_Frame (newtime - oldtime);
		oldtime = newtime;
	}
	return 0;
}