#!/usr/bin/env python3

# Delete "set service dhcp-relay relay-options port" option
# Delete "set service dhcpv6-relay listen-port" option

import sys

from vyos.configtree import ConfigTree

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

file_name = sys.argv[1]

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

config = ConfigTree(config_file)

if not (config.exists(['service', 'dhcp-relay', 'relay-options', 'port']) or config.exists(['service', 'dhcpv6-relay', 'listen-port'])):
    # Nothing to do
    sys.exit(0)
else:
    # Delete abandoned node
    config.delete(['service', 'dhcp-relay', 'relay-options', 'port'])
    # Delete abandoned node
    config.delete(['service', 'dhcpv6-relay', 'listen-port'])

    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))
        sys.exit(1)