#!/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/>.

# T4660: change cli
#     from: set policy route-map FOO rule 10 set community 'TEXT'
#     Multiple value
#     to: set policy route-map FOO rule 10 set community replace <community>
#     Multiple value
#     to: set policy route-map FOO rule 10 set community add <community>
#     to: set policy route-map FOO rule 10 set community none
#
#     from: set policy route-map FOO rule 10 set large-community 'TEXT'
#     Multiple value
#     to: set policy route-map FOO rule 10 set large-community replace <community>
#     Multiple value
#     to: set policy route-map FOO rule 10 set large-community add <community>
#     to: set policy route-map FOO rule 10 set large-community none
#
#     from: set policy route-map FOO rule 10 set extecommunity [rt|soo] 'TEXT'
#     Multiple value
#     to: set policy route-map FOO rule 10 set extcommunity [rt|soo] <community>

from sys import argv
from sys import exit

from vyos.configtree import ConfigTree


# Migration function for large and regular communities
def community_migrate(config: ConfigTree, rule: list[str]) -> bool:
    """

    :param config: configuration object
    :type config: ConfigTree
    :param rule: Path to variable
    :type rule: list[str]
    :return: True if additive presents in community string
    :rtype: bool
    """
    community_list = list((config.return_value(rule)).split(" "))

    if 'none' in community_list:
        config.set(rule + ['none'])
        return False
    else:
        community_action: str = 'replace'
        if 'additive' in community_list:
            community_action = 'add'
            community_list.remove('additive')
        for community in community_list:
            if len(community):
                config.set(rule + [community_action], value=community,
                        replace=False)
                config.delete(rule)
        if community_action == 'replace':
            return False
        else:
            return True


# Migration function for extcommunities
def extcommunity_migrate(config: ConfigTree, rule: list[str]) -> None:
    """

    :param config: configuration object
    :type config: ConfigTree
    :param rule: Path to variable
    :type rule: list[str]
    """
    # if config.exists(rule + ['bandwidth']):
    #     bandwidth: str = config.return_value(rule + ['bandwidth'])
    #     config.delete(rule + ['bandwidth'])
    #     config.set(rule + ['bandwidth'], value=bandwidth)

    if config.exists(rule + ['rt']):
        community_list = list((config.return_value(rule + ['rt'])).split(" "))
        config.delete(rule + ['rt'])
        for community in community_list:
            config.set(rule + ['rt'], value=community, replace=False)

    if config.exists(rule + ['soo']):
        community_list = list((config.return_value(rule + ['soo'])).split(" "))
        config.delete(rule + ['soo'])
        for community in community_list:
            config.set(rule + ['soo'], value=community, replace=False)


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

file_name: str = argv[1]

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

base: list[str] = ['policy', 'route-map']
config = ConfigTree(config_file)

if not config.exists(base):
    # Nothing to do
    exit(0)

for route_map in config.list_nodes(base):
    if not config.exists(base + [route_map, 'rule']):
        continue
    for rule in config.list_nodes(base + [route_map, 'rule']):
        base_rule: list[str] = base + [route_map, 'rule', rule, 'set']

        # IF additive presents in coummunity then comm-list is redundant
        isAdditive: bool = True
        #### Change Set community ########
        if config.exists(base_rule + ['community']):
            isAdditive = community_migrate(config,
                                           base_rule + ['community'])

        #### Change Set community-list delete migrate ########
        if config.exists(base_rule + ['comm-list', 'comm-list']):
            if isAdditive:
                tmp = config.return_value(
                    base_rule + ['comm-list', 'comm-list'])
                config.delete(base_rule + ['comm-list'])
                config.set(base_rule + ['community', 'delete'], value=tmp)
            else:
                config.delete(base_rule + ['comm-list'])

        isAdditive = False
        #### Change Set large-community ########
        if config.exists(base_rule + ['large-community']):
            isAdditive = community_migrate(config,
                                           base_rule + ['large-community'])

        #### Change Set large-community delete by List ########
        if config.exists(base_rule + ['large-comm-list-delete']):
            if isAdditive:
                tmp = config.return_value(
                    base_rule + ['large-comm-list-delete'])
                config.delete(base_rule + ['large-comm-list-delete'])
                config.set(base_rule + ['large-community', 'delete'],
                           value=tmp)
            else:
                config.delete(base_rule + ['large-comm-list-delete'])

        #### Change Set extcommunity ########
        extcommunity_migrate(config, base_rule + ['extcommunity'])
try:
    with open(file_name, 'w') as f:
        f.write(config.to_string())
except OSError as e:
    print(f'Failed to save the modified config: {e}')
    exit(1)