/*
 * cfgfile.c -- misc reads from the config file
 *
 * Copyright (C) 2008-2012  O.Sezer <sezero@users.sourceforge.net>
 *
 * 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.,
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include "q_defs.h"


static fshandle_t               *cfg_file;

/*
===================
CFG_ReadCvars

used for doing early reads from config.cfg searching the list
of given cvar names for the user-set values. a temporary
solution until we merge a better cvar system.
the num_vars argument must be the exact number of strings in the
array, otherwise I have nothing against going out of bounds.
===================
*/
void CFG_ReadCvars(const char **vars, int32_t num_vars)
{
	char    buff[1024], *tmp;
	int32_t                 i, j;

	if(!cfg_file || num_vars < 1)
		return;

	j = 0;

	do
	{
		i = 0;
		memset(buff, 0, sizeof(buff));
		// we expect a line in the format that Cvar_WriteVariables
		// writes to the config file. although I'm trying to be as
		// much cautious as possible, if the user screws it up by
		// editing it, it's his fault.
		if(FS_fgets(buff, sizeof(buff), cfg_file))
		{
			// remove end-of-line characters
			while(buff[i])
			{
				if(buff[i] == '\r' || buff[i] == '\n')
					buff[i] = '\0';
				// while we're here, replace tabs with spaces
				if(buff[i] == '\t')
					buff[i] = ' ';
				i++;
			}
			// go to the last character
			while(buff[i] == 0 && i > 0)
				i--;
			// remove trailing spaces
			while(i > 0)
			{
				if(buff[i] == ' ')
				{
					buff[i] = '\0';
					i--;
				}
				else
					break;
			}

			// the line must end with a quotation mark
			if(buff[i] != '\"')
				continue;
			buff[i] = '\0';

			for(i = 0; i < num_vars && vars[i]; i++)
			{
				// look for the cvar name + one space
				tmp = strstr(buff, va("%s ", vars[i]));
				if(tmp != buff)
					continue;
				// locate the first quotation mark
				tmp = strchr(buff, '\"');
				if(tmp)
				{
					Cvar_Set(vars[i], tmp + 1);
					j++;
					break;
				}
			}
		}

		if(j == num_vars)
			break;

	}
	while(!FS_feof(cfg_file) && !FS_ferror(cfg_file));

	FS_rewind(cfg_file);
}

/*
===================
CFG_ReadCvarOverrides

convenience function, reading the "+" command line override
values of cvars in the given list. doesn't do anything with
the config file.
===================
*/
void CFG_ReadCvarOverrides(const char **vars, int32_t num_vars)
{
	char    buff[64];
	int32_t         i, j;

	if(num_vars < 1)
		return;

	buff[0] = '+';

	for(i = 0; i < num_vars; i++)
	{
		q_strlcpy(&buff[1], vars[i], strsizeof(buff));
		j = COM_CheckParm(buff);
		if(j != 0 && j < com_argc - 1)
		{
			if(com_argv[j + 1][0] != '-' && com_argv[j + 1][0] != '+')
				Cvar_Set(vars[i], com_argv[j + 1]);
		}
	}
}

void CFG_CloseConfig(void)
{
	if(cfg_file)
	{
		FS_fclose(cfg_file);
		Z_Free(cfg_file);
		cfg_file = NULL;
	}
}

int32_t CFG_OpenConfig(const char *cfg_name)
{
	FILE    *f;
	long            length;
	bool    pak;

	CFG_CloseConfig();

	length = (long) COM_FOpenFile(cfg_name, &f, NULL);
	pak = file_from_pak;
	if(length == -1)
		return -1;

	cfg_file = (fshandle_t *) Z_Malloc(sizeof(fshandle_t));
	cfg_file->file = f;
	cfg_file->start = ftell(f);
	cfg_file->pos = 0;
	cfg_file->length = length;
	cfg_file->pak = pak;

	return 0;
}