#!/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/>.

# T5681: Firewall re-writing. Simplify cli when mathcing interface
# From
#   'set nat [source|destination] rule X [inbound-interface|outbound interface] interface-name <iface>'
#   'set nat [source|destination] rule X [inbound-interface|outbound interface] interface-group <iface_group>'
# to
#   'set nat [source|destination] rule X [inbound-interface|outbound interface] name <iface>'
#   'set nat [source|destination] rule X [inbound-interface|outbound interface] group <iface_group>'

from sys import argv,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)

if not config.exists(['nat']):
    # Nothing to do
    exit(0)

for direction in ['source', 'destination']:
    # If a node doesn't exist, we obviously have nothing to do.
    if not config.exists(['nat', direction]):
        continue

    # However, we also need to handle the case when a 'source' or 'destination' sub-node does exist,
    # but there are no rules under it.
    if not config.list_nodes(['nat', direction]):
        continue

    for rule in config.list_nodes(['nat', direction, 'rule']):
        base = ['nat', direction, 'rule', rule]
        for iface in ['inbound-interface','outbound-interface']:
            if config.exists(base + [iface]):
                if config.exists(base + [iface, 'interface-name']):
                    tmp = config.return_value(base + [iface, 'interface-name'])
                    config.delete(base + [iface, 'interface-name'])
                    config.set(base + [iface, 'name'], value=tmp)

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)