#!/usr/bin/env python3
#
# Copyright (C) 2020 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/>.

# - remove primary/secondary identifier from nameserver
# - Unifi RADIUS configuration by placing it all under "authentication radius" node

import os
import sys

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

if (len(argv) < 1):
    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']
if not config.exists(base):
    # Nothing to do
    exit(0)
else:

    # Migrate IPv4 DNS servers
    dns_base = base + ['dns-servers']
    if config.exists(dns_base):
        for server in ['server-1', 'server-2']:
          if config.exists(dns_base + [server]):
            dns = config.return_value(dns_base + [server])
            config.set(base + ['name-server'], value=dns, replace=False)

        config.delete(dns_base)

    # Migrate IPv6 DNS servers
    dns_base = base + ['dnsv6-servers']
    if config.exists(dns_base):
        for server in ['server-1', 'server-2', 'server-3']:
          if config.exists(dns_base + [server]):
            dns = config.return_value(dns_base + [server])
            config.set(base + ['name-server'], value=dns, replace=False)

        config.delete(dns_base)

    # Migrate radius-settings node to RADIUS and use this as base for the
    # later migration of the RADIUS servers - this will save a lot of code
    radius_settings = base + ['authentication', 'radius-settings']
    if config.exists(radius_settings):
        config.rename(radius_settings, 'radius')

    # Migrate RADIUS server
    radius_server = base + ['authentication', 'radius-server']
    if config.exists(radius_server):
        new_base = base + ['authentication', 'radius', 'server']
        config.set(new_base)
        config.set_tag(new_base)
        for server in config.list_nodes(radius_server):
            old_base = radius_server + [server]
            config.copy(old_base, new_base + [server])

            # remove old req-limit node
            if config.exists(new_base + [server, 'req-limit']):
                config.delete(new_base + [server, 'req-limit'])

        config.delete(radius_server)

    # Migrate IPv6 prefixes
    ipv6_base = base + ['client-ipv6-pool']
    if config.exists(ipv6_base + ['prefix']):
        prefix_old = config.return_values(ipv6_base + ['prefix'])
        # delete old prefix CLI nodes
        config.delete(ipv6_base + ['prefix'])
        # create ned prefix tag node
        config.set(ipv6_base + ['prefix'])
        config.set_tag(ipv6_base + ['prefix'])

        for p in prefix_old:
            prefix = p.split(',')[0]
            mask = p.split(',')[1]
            config.set(ipv6_base + ['prefix', prefix, 'mask'], value=mask)

    if config.exists(ipv6_base + ['delegate-prefix']):
        prefix_old = config.return_values(ipv6_base + ['delegate-prefix'])
        # delete old delegate prefix CLI nodes
        config.delete(ipv6_base + ['delegate-prefix'])
        # create ned delegation tag node
        config.set(ipv6_base + ['delegate'])
        config.set_tag(ipv6_base + ['delegate'])

        for p in prefix_old:
            prefix = p.split(',')[0]
            mask = p.split(',')[1]
            config.set(ipv6_base + ['delegate', prefix, 'delegation-prefix'], value=mask)

    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)