args@{ config, lib, meta, name, sources, ... }:

let
  inherit (lib)
    mkEnableOption
    mkIf;

  dns = import sources."dns.nix";

  cfg = config.dgn-dns;
in

{
  options.dgn-dns = {
    enable = mkEnableOption "an authoritative dns service on this server.";
  };


  config = mkIf cfg.enable {
    services.nsd = {
      enable = true;

      interfaces = meta.network.${name}.addresses.public;

      zones = import ./zones (args // { inherit dns; });
    };

    networking.firewall = {
      allowedTCPPorts = [ 53 ];
      allowedUDPPorts = [ 53 ];
    };
  };
}