#!/usr/bin/env python3
#
# Copyright (C) 2023 VyOS maintainers and contributors
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 or later as
# published by the Free Software Foundation.
#
# 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, see <http://www.gnu.org/licenses/>.

# - changed cli of all named pools
# - moved gateway-address from pool to global configuration with / netmask
#   gateway can exist without pool if radius is used
#   and Framed-ip-address is transmited
# - There are several gateway-addresses in ipoe
# - default-pool by migration.
#       1. The first pool that contains next-poll.
#       2. Else, the first pool in the list

import os

from sys import argv
from sys import exit
from vyos.configtree import ConfigTree


if len(argv) < 2:
    print("Must specify file name!")
    exit(1)

file_name = argv[1]

with open(file_name, 'r') as f:
    config_file = f.read()

config = ConfigTree(config_file)
base = ['service', 'ipoe-server']
pool_base = base + ['client-ip-pool']
if not config.exists(base):
    exit(0)

if not config.exists(pool_base):
    exit(0)
default_pool = ''
gateway = ''

#named pool migration
namedpools_base = pool_base + ['name']

for pool_name in config.list_nodes(namedpools_base):
    pool_path = namedpools_base + [pool_name]
    if config.exists(pool_path + ['subnet']):
        subnet = config.return_value(pool_path + ['subnet'])
        config.set(pool_base + [pool_name, 'range'], value=subnet, replace=False)
        # Get netmask from subnet
        mask = subnet.split("/")[1]
    if config.exists(pool_path + ['next-pool']):
        next_pool = config.return_value(pool_path + ['next-pool'])
        config.set(pool_base + [pool_name, 'next-pool'], value=next_pool)
        if not default_pool:
            default_pool = pool_name
    if config.exists(pool_path + ['gateway-address']) and mask:
        gateway = f'{config.return_value(pool_path + ["gateway-address"])}/{mask}'
        config.set(base + ['gateway-address'], value=gateway, replace=False)

if not default_pool and config.list_nodes(namedpools_base):
    default_pool = config.list_nodes(namedpools_base)[0]

config.delete(namedpools_base)

if default_pool:
    config.set(base + ['default-pool'], value=default_pool)
# format as tag node
config.set_tag(pool_base)

try:
    with open(file_name, 'w') as f:
        f.write(config.to_string())
except OSError as e:
    print("Failed to save the modified config: {}".format(e))
    exit(1)