#!/usr/bin/env python3

from bundlewrap.repo import Repository
from os.path import realpath, dirname
from sys import argv
from ipaddress import ip_network, ip_interface
import argparse


# get info from repo
repo = Repository(dirname(dirname(realpath(__file__))))
server_node = repo.get_node('htz.mails')
available_clients = server_node.metadata.get('wireguard/clients').keys()

# parse args
parser = argparse.ArgumentParser(description='Generate WireGuard client configuration.')
parser.add_argument('client', choices=available_clients, help='The client name to generate the configuration for.')
args = parser.parse_args()

# get cert
data = server_node.metadata.get(f'wireguard/clients/{args.client}')
vpn_network = ip_interface(server_node.metadata.get('wireguard/my_ip')).network
allowed_ips = [
    vpn_network,
    ip_interface(server_node.metadata.get('network/internal/ipv4')).network,
]
for peer in server_node.metadata.get('wireguard/s2s').values():
    for network in peer['allowed_ips']:
        if not ip_network(network).subnet_of(vpn_network):
            allowed_ips.append(ip_network(network))

conf = f'''
[Interface]
PrivateKey = {repo.libs.wireguard.privkey(data['peer_id'])}
ListenPort = 51820
Address = {data['peer_ip']}
DNS = 172.30.0.1

[Peer]
PublicKey = {repo.libs.wireguard.pubkey(server_node.metadata.get('id'))}
PresharedKey = {repo.libs.wireguard.psk(data['peer_id'], server_node.metadata.get('id'))}
AllowedIPs = {', '.join(str(client_route) for client_route in sorted(allowed_ips))}
Endpoint = {ip_interface(server_node.metadata.get('network/external/ipv4')).ip}:51820
PersistentKeepalive = 10
'''

answer = input("print config or qrcode? [Cq]: ").strip().upper()
match answer:
    case '' | 'C':
        print('>>>>>>>>>>>>>>>')
        print(conf)
        print('<<<<<<<<<<<<<<<')
    case 'Q':
        import pyqrcode
        print(pyqrcode.create(conf).terminal(quiet_zone=1))
    case _:
        print(f'Invalid option "{answer}".')
        exit(1)