{ config, pkgs, ... }:

{
  imports =
    [ # Include the results of the hardware scan.
      ./hardware-configuration.nix
      ./nginx.nix
   ];

  # Use the systemd-boot EFI boot loader.
  boot.loader.systemd-boot.enable = true;
  boot.loader.efi.canTouchEfiVariables = true;

  networking.hostName = "pre-router"; # Define your hostname.

  # The global useDHCP flag is deprecated, therefore explicitly set to false here.
  # Per-interface useDHCP will be mandatory in the future, so this generated config
  # replicates the default behaviour.
  networking.useDHCP = false;
  #networking.interfaces.ens18.useDHCP = false;
  #networking.interfaces.ens19.useDHCP = false;

  environment.systemPackages = with pkgs; [
    ethtool             # manage NIC settings (offload, NIC feeatures, ...)
    conntrack-tools     # view network connection states
    wireguard-tools
  ];

  networking.nat = {
    enable = true;
    externalInterface = "ens18";
    internalIPs = [
      "10.42.0.0/16"
    ];
  };

  boot.kernel.sysctl = {
    "net.ipv6.conf.all.forwarding" = true;
    "net.ipv6.conf.default.forwarding" = true;
  };

  networking.interfaces.ens18.useDHCP = true;
  networking.interfaces.ens19.useDHCP = false;
  networking.interfaces.ens19.ipv6.addresses = [
    { address = "fd00:10:42:10::25"; prefixLength = 64; }
    { address = "2a01:4f8:1c0c:8221::25"; prefixLength = 64; }
  ];
  networking.interfaces.ens19.ipv4.addresses = [
    { address = "10.42.10.25"; prefixLength = 24; }
  ];
  networking.interfaces.ens19.ipv6.routes = [
    { address = "fd00:10:42::"; prefixLength = 48; via = "fd00:10:42:10::1"; }
  ];
  networking.interfaces.ens19.ipv4.routes = [
    { address = "10.42.0.0"; prefixLength = 16; via = "10.42.10.1"; }
  ];

  networking.wireguard = {
    enable = true;
    interfaces = {
      wg0 = {
        ips = [ "fe80::42:10:1/64" ];
        privateKeyFile = "/var/src/secrets/wireguard/wg0";
        allowedIPsAsRoutes = false;
        peers = [{
          publicKey = "Y++eB9SfU17zB4mJ/6AaN761tngXAyTNoVaPNKmuvls=";
          allowedIPs = [ "::/0"  ];
          endpoint = "78.47.183.82:51876";
          #endpoint = "gatekeeper.net.clerie.de:51876";
          persistentKeepalive = 25;
        }];
      };
    };
  };

  networking.localCommands = ''
    ip -6 route add default dev wg0 table 100
  '';

  clerie.policyrouting.enable = true;
  clerie.policyrouting.rules6 = [
    { rule = "lookup main suppress_prefixlength 0"; prio = 10000; }
    { rule = "from 2a01:4f8:1c0c:8221::/64 lookup 100"; prio = 19000; }
  ];

  # This value determines the NixOS release from which the default
  # settings for stateful data, like file locations and database versions
  # on your system were taken. It‘s perfectly fine and recommended to leave
  # this value at the release version of the first install of this system.
  # Before changing this value read the documentation for this option
  # (e.g. man configuration.nix or on https://nixos.org/nixos/options.html).
  system.stateVersion = "21.11"; # Did you read the comment?

}