/*---------------------------------------------------------------------------*
 * <RCS keywords>
 *
 * C++ Library
 *
 * Copyright 1992-1994, David Gottner
 *
 *                    All Rights Reserved
 *
 * Permission to use, copy, modify, and distribute this software and its 
 * documentation for any purpose and without fee is hereby granted, 
 * provided that the above copyright notice, this permission notice and
 * the following disclaimer notice appear unmodified in all copies.
 *
 * I DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL I
 * BE LIABLE FOR ANY SPECIAL, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY
 * DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA, OR PROFITS, WHETHER
 * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 * Nevertheless, I would like to know about bugs in this library or
 * suggestions for improvment.  Send bug reports and feedback to
 * davegottner@delphi.com.
 *---------------------------------------------------------------------------*/

/* Modified to support --help and --version, as well as /? on Windows
 * by Georg Brandl. */

#include <Python.h>
#include <stdio.h>
#include <string.h>
#include <wchar.h>
#include <pygetopt.h>

#ifdef __cplusplus
extern "C" {
#endif

int _PyOS_opterr = 1;          /* generate error messages */
int _PyOS_optind = 1;          /* index into argv array   */
wchar_t *_PyOS_optarg = NULL;     /* optional argument       */

int _PyOS_GetOpt(int argc, wchar_t **argv, wchar_t *optstring)
{
	static wchar_t *opt_ptr = L"";
	wchar_t *ptr;
	wchar_t option;

	if (*opt_ptr == '\0') {

		if (_PyOS_optind >= argc)
			return -1;
#ifdef MS_WINDOWS
		else if (wcscmp(argv[_PyOS_optind], L"/?") == 0) {
			++_PyOS_optind;
			return 'h';
		}
#endif

		else if (argv[_PyOS_optind][0] != L'-' ||
		         argv[_PyOS_optind][1] == L'\0' /* lone dash */ )
			return -1;

		else if (wcscmp(argv[_PyOS_optind], L"--") == 0) {
			++_PyOS_optind;
			return -1;
		}

		else if (wcscmp(argv[_PyOS_optind], L"--help") == 0) {
			++_PyOS_optind;
			return 'h';
		}

		else if (wcscmp(argv[_PyOS_optind], L"--version") == 0) {
			++_PyOS_optind;
			return 'V';
		}


		opt_ptr = &argv[_PyOS_optind++][1]; 
	}

	if ( (option = *opt_ptr++) == L'\0')
		return -1;

	if (option == 'J') {
		fprintf(stderr, "-J is reserved for Jython\n");
		return '_';
	}

	if (option == 'X') {
		fprintf(stderr,
		  "-X is reserved for implementation-specific arguments\n");
		return '_';
	}

	if ((ptr = wcschr(optstring, option)) == NULL) {
		if (_PyOS_opterr)
		  fprintf(stderr, "Unknown option: -%c\n", (char)option);

		return '_';
	}

	if (*(ptr + 1) == L':') {
		if (*opt_ptr != L'\0') {
			_PyOS_optarg  = opt_ptr;
			opt_ptr = L"";
		}

		else {
			if (_PyOS_optind >= argc) {
				if (_PyOS_opterr)
					fprintf(stderr,
						"Argument expected for the -%c option\n", (char)option);
				return '_';
			}

			_PyOS_optarg = argv[_PyOS_optind++];
		}
	}

	return option;
}

#ifdef __cplusplus
}
#endif