{ config, pkgs, ... }:

{
  # make the tailscale command usable to users
  environment.systemPackages = [ pkgs.tailscale ];

  # enable the tailscale service
  services.tailscale.enable = true;
  # create a oneshot job to authenticate to Tailscale
  systemd.services.tailscale-autoconnect = {
    description = "Automatic connection to Tailscale";
  
    # make sure tailscale is running before trying to connect to tailscale
    after = [ "network-pre.target" "tailscale.service" ];
    wants = [ "network-pre.target" "tailscale.service" ];
    wantedBy = [ "multi-user.target" ];
  
    # set this service as a oneshot job
    serviceConfig.Type = "oneshot";
  
    # have the job run this shell script
    script = with pkgs; ''
      # wait for tailscaled to settle
      sleep 2
  
      # check if we are already authenticated to tailscale
      status="$(${tailscale}/bin/tailscale status -json | ${jq}/bin/jq -r .BackendState)"
      if [ $status = "Running" ]; then # if so, then do nothing
        exit 0
      fi
  
      # otherwise authenticate with tailscale
      ${tailscale}/bin/tailscale up -authkey tskey-auth-kMsXxz4CNTRL-uv16NoKao8LtAtEphy8qCLFPqa1LtqwoD
    '';
  };
}
