from celery import shared_task
from .models import *

@shared_task
def configure_wireguard_server(vpnpool):
    print(f"Configuring {vpnpool.vpn_server_hostname}")

    wireguard_config_filename =  '/etc/wireguard/{}.conf'.format(vpnpool.network)

    @property
    def wireguard_config(self):
        wireguard_config = [
            """
[Interface]
ListenPort = 51820
PrivateKey = {privatekey}
""".format(privatekey=self.wireguard_private_key) ]

        peers = []

        for reservation in self.vpnnetworkreservation_set.filter(status='used'):
            public_key = reservation.vpnnetwork_set.first().wireguard_public_key
            peer_network = "{}/{}".format(reservation.address, self.subnetwork_size)
            owner = reservation.vpnnetwork_set.first().owner

            peers.append("""
# Owner: {owner}
[Peer]
PublicKey = {public_key}
AllowedIPs = {peer_network}
""".format(
    owner=owner,
    public_key=public_key,
    peer_network=peer_network))

        wireguard_config.extend(peers)

        return "\n".join(wireguard_config)


    def configure_wireguard_vpnserver(self):
        """
        This method is designed to run as a celery task and should
        not be called directly from the web
        """

        # subprocess, ssh

        pass



    def num_maximum_networks(self):
        """
        sample:
        network_size = 40
        subnetwork_size = 48
        maximum_networks = 2^(48-40)

        2nd sample:
        network_size = 8
        subnetwork_size = 24
        maximum_networks = 2^(24-8)
        """

        return 2**(self.subnetwork_mask - self.network_mask)