/* parse_argument.h */

/*
remap
Copyright (C) 2006 Fabrice Ducos, fabrice.ducos@icare.univ-lille1.fr

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.
*/

#ifndef PARSE_ARGUMENT_H
#define PARSE_ARGUMENT_H

#include "grid.h"

/**
 * parses a user argument in order to extract some useful values for a grid_type structure.
 * argv[iarg] must match the regular expression ^([^[@/]+)(\\[([0-9]+)\\])?(/[^@]+)?@(.*)$
 * which means in clear one of the four alternatives :
 * - input_dataset\@input_file
 * - input_dataset[ichannel]\@input_file
 * - input_dataset/output_dataset\@input_file
 * - input_dataset[ichannel]/output_dataset\@input_file
 *
 * (with : ichannel an integer, input_dataset a char *, output_dataset a char *, and input_file a char *)
 *
 * 
 *
 * @param iarg the index of the argument to parse (between 1 and argc - 1)
 * @param argv the list of the command arguments, from ::main
 * @param grid a pointer to a grid_type structure to update with infos found in the i-th argument
 *
 * @returns 0 on success, -1 on failure; the current implementation actually exits
 * in a brutal way when a invalid argument is found, simply sending an error message on the standard error as a side
 * effect. Indeed, an invalid argument was seen as a fatal error in the application context (no processing can be done),
 * so it was judged useless to continue.
 *
 *
 * The fields of grid_type updated by parse_argument include:
 * - grid_type::input_dataset
 * - grid_type::output_dataset (set to grid_type::input_dataset if not found in the regexp)
 * - grid_type::file
 * - grid_type::ichannel (set to 0 if not found in the regexp)
 *
 * @see ::tokenize (called by ::parse_argument)
 */
extern int parse_argument(int iarg, char *argv[], grid_type *grid);

#endif