# Copyright 2024 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/>.

# T3316:
# - Migrate dhcp options under new option node
# - Add subnet IDs to existing subnets

from vyos.configtree import ConfigTree

base = ['service', 'dhcp-server', 'shared-network-name']

option_nodes = ['bootfile-name', 'bootfile-server', 'bootfile-size', 'captive-portal',
                'client-prefix-length', 'default-router', 'domain-name', 'domain-search',
                'name-server', 'ip-forwarding', 'ipv6-only-preferred', 'ntp-server',
                'pop-server', 'server-identifier', 'smtp-server', 'static-route',
                'tftp-server-name', 'time-offset', 'time-server', 'time-zone',
                'vendor-option', 'wins-server', 'wpad-url']


def migrate(config: ConfigTree) -> None:
    if not config.exists(base):
        # Nothing to do
        return

    subnet_id = 1

    for network in config.list_nodes(base):
        for option in option_nodes:
            if config.exists(base + [network, option]):
                config.set(base + [network, 'option'])
                config.copy(base + [network, option], base + [network, 'option', option])
                config.delete(base + [network, option])

        if config.exists(base + [network, 'subnet']):
            for subnet in config.list_nodes(base + [network, 'subnet']):
                base_subnet = base + [network, 'subnet', subnet]

                for option in option_nodes:
                    if config.exists(base_subnet + [option]):
                        config.set(base_subnet + ['option'])
                        config.copy(base_subnet + [option], base_subnet + ['option', option])
                        config.delete(base_subnet + [option])

                config.set(base_subnet + ['subnet-id'], value=subnet_id)
                subnet_id += 1