{ config, lib, ... }:
let
  cfg = config.services.syncthing;
  fqdn = "${cfg.subdomain}.${config.networking.domain}";
in
{
  options.services.syncthing = {
    subdomain = lib.mkOption {
      type = lib.types.str;
    };
    port = lib.mkOption {
      type = lib.types.int;
      default = 8384;
    };
  };

  config = lib.mkIf cfg.enable {
    services = {
      syncthing = {
        openDefaultPorts = true;
        guiAddress = "[::1]:${toString cfg.port}";
        settings.gui.insecureSkipHostCheck = true;
      };

      webserver = {
        enable = lib.mkDefault true;
        vHosts.${fqdn}.locations."/".proxyPort = cfg.port;
      };
    };

    systemd.services.syncthing.serviceConfig =
      lib.mkIf
        (
          cfg.dataDir == "/var/lib/syncthing" || cfg.dataDir == null || cfg.configDir == "/var/lib/syncthing"
        )
        {
          StateDirectory = "syncthing";
        };
  };
}