nixos/modules/services/xrdp.nix

inputs:
{
  options.nixos.services.xrdp = let inherit (inputs.lib) mkOption types; in
  {
    enable = mkOption { type = types.bool; default = false; };
    port = mkOption { type = types.ints.unsigned; default = 3389; };
    hostname = mkOption { type = types.nullOr (types.nonEmptyListOf types.nonEmptyStr); default = null; };
  };
  config = let inherit (inputs.config.nixos.services) xrdp;
    in inputs.lib.mkIf xrdp.enable (inputs.lib.mkMerge
    [
      {
        services.xrdp =
        {
          enable = true;
          port = xrdp.port;
          openFirewall = true;
          defaultWindowManager = "${inputs.pkgs.plasma-workspace}/bin/startplasma-x11";
        };
        nixos.services.xray.client.v2ray-forwarder.noproxyTcpPorts = [ xrdp.port ];
      }
      (
        inputs.lib.mkIf (xrdp.hostname != null)
        (
          let mainDomain = builtins.elemAt xrdp.hostname 0;
          in
          {
            services.xrdp =
              let keydir = inputs.config.security.acme.certs.${mainDomain}.directory;
              in { sslCert = "${keydir}/full.pem"; sslKey = "${keydir}/key.pem"; };
            nixos.services.acme.cert.${mainDomain} =
              { domains = xrdp.hostname; group = inputs.config.systemd.services.xrdp.serviceConfig.Group; };
          }
        )
      )
    ]);
}