#!/usr/bin/env python3

# Copyright 2019-2022 VyOS maintainers and contributors <maintainers@vyos.io>
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library 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
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library.  If not, see <http://www.gnu.org/licenses/>.

from argparse import ArgumentParser
from sys import exit

from vyos.template import is_ipv4

COMM_MAX_2_OCTET: int = 65535
COMM_MAX_4_OCTET: int = 4294967295

if __name__ == '__main__':
    # add an argument with community
    parser: ArgumentParser = ArgumentParser()
    parser.add_argument('community', type=str)
    args = parser.parse_args()
    community: str = args.community
    if community.count(':') != 1:
        print("Invalid community format")
        exit(1)
    try:
        # try to extract community parts from an argument
        comm_left: str = community.split(':')[0]
        comm_right: int = int(community.split(':')[1])

        # check if left part is an IPv4 address
        if is_ipv4(comm_left) and 0 <= comm_right <= COMM_MAX_2_OCTET:
            exit()
        # check if a left part is a number
        if 0 <= int(comm_left) <= COMM_MAX_2_OCTET \
                and 0 <= comm_right <= COMM_MAX_4_OCTET:
            exit()

    except Exception:
        # fail if something was wrong
        print("Invalid community format")
        exit(1)

    # fail if none of validators catched the value
    print("Invalid community format")
    exit(1)