#!/usr/bin/env python
#
# Copyright (c) 2016 Stefan Seefeld
# All rights reserved.
#
# This file is part of Faber. It is made available under the
# Boost Software License, Version 1.0.
# (Consult LICENSE or http://www.boost.org/LICENSE_1_0.txt)

import argparse


class PosArgsParser(argparse.Action):
    def __init__(self, option_strings, dest, **kwds):
        argparse.Action.__init__(self, option_strings, dest, **kwds)
    # Separates positional arguments into targets and parameters
    def __call__(self, parser, namespace, values, option_string=None):
        if namespace.parameters is None:
            namespace.parameters={}
        if not namespace.goals:
            namespace.goals=[]
        for v in values:
            if '=' in v:
                name, value = v.split('=', 1)
                if name in namespace.parameters:
                    if type(namespace.parameters[name]) is not list:
                        namespace.parameters[name] = [namespace.parameters[name]]
                    namespace.parameters[name].append(value)
                else:
                    namespace.parameters[name] = value
            else:
                namespace.goals.append(v)


def make_parser(prog='faber'):

    parser = argparse.ArgumentParser(prog=prog,
                                     description='Faber is a construction tool.')
    parser.add_argument('goals', metavar='GOAL', nargs='*',
                        action=PosArgsParser,
                        help='a goal to update')
    parser.add_argument('parameters', metavar='PARAMETER=VALUE', nargs='*',
                        action=PosArgsParser,
                        help='a parameter value')
    parser.add_argument('--info', action='store_true',
                        help='print information about the build logic')
    return parser


def main(argv):

    parser = make_parser(argv[0])
    args = parser.parse_args(argv[1:])


if __name__ == '__main__':

    import sys
    sys.exit(0 if main(sys.argv) else 1)