#!/usr/bin/env python3
#
# Copyright (C) 2022 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/>.

# T2199: Migrate interface policy nodes to policy route <name> interface <ifname>

import re

from sys import argv
from sys import exit

from vyos.configtree import ConfigTree
from vyos.ifconfig import Section

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()

base4 = ['policy', 'route']
base6 = ['policy', 'route6']
config = ConfigTree(config_file)

if not config.exists(base4) and not config.exists(base6):
    # Nothing to do
    exit(0)

def migrate_interface(config, iftype, ifname, vif=None, vifs=None, vifc=None):
    if_path = ['interfaces', iftype, ifname]
    ifname_full = ifname

    if vif:
        if_path += ['vif', vif]
        ifname_full = f'{ifname}.{vif}'
    elif vifs:
        if_path += ['vif-s', vifs]
        ifname_full = f'{ifname}.{vifs}'
        if vifc:
            if_path += ['vif-c', vifc]
            ifname_full = f'{ifname}.{vifs}.{vifc}'

    if not config.exists(if_path + ['policy']):
        return

    if config.exists(if_path + ['policy', 'route']):
        route_name = config.return_value(if_path + ['policy', 'route'])
        config.set(base4 + [route_name, 'interface'], value=ifname_full, replace=False)

    if config.exists(if_path + ['policy', 'route6']):
        route_name = config.return_value(if_path + ['policy', 'route6'])
        config.set(base6 + [route_name, 'interface'], value=ifname_full, replace=False)

    config.delete(if_path + ['policy'])

for iftype in config.list_nodes(['interfaces']):
    for ifname in config.list_nodes(['interfaces', iftype]):
        migrate_interface(config, iftype, ifname)

        if config.exists(['interfaces', iftype, ifname, 'vif']):
            for vif in config.list_nodes(['interfaces', iftype, ifname, 'vif']):
                migrate_interface(config, iftype, ifname, vif=vif)

        if config.exists(['interfaces', iftype, ifname, 'vif-s']):
            for vifs in config.list_nodes(['interfaces', iftype, ifname, 'vif-s']):
                migrate_interface(config, iftype, ifname, vifs=vifs)

                if config.exists(['interfaces', iftype, ifname, 'vif-s', vifs, 'vif-c']):
                    for vifc in config.list_nodes(['interfaces', iftype, ifname, 'vif-s', vifs, 'vif-c']):
                        migrate_interface(config, iftype, ifname, vifs=vifs, vifc=vifc)

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)