{ config, lib, pkgs, ... }:
let
  inherit (lib) mkIf;

  cfg = config.pepe.services.headscale;
in
{
  options.pepe.services.headscale = with lib; {
    enable = mkEnableOption "Enable Headscale";
    package = mkPackageOption pkgs "headscale" { };
    domain = mkOption {
      type = types.str;
      default = null;
      description = "Domain for the Headscale service.";
    };
    host = mkOption {
      type = types.str;
      default = "127.0.0.1";
      description = "Host for the Headscale service.";
    };
    port = mkOption {
      type = types.int;
      default = 1194;
      description = "Port for the Headscale service.";
    };
    settings = mkOption {
      type = types.submodule {
        freeformType = types.attrsOf types.anything;
        options = {
          server_url = mkOption {
            type = types.str;
            default = "https://${cfg.domain}";
          };
          dns = mkOption {
            type = types.submodule {
              options = {
                magic_dns = mkOption {
                  type = types.bool;
                  default = false;
                };
                override_local_dns = mkOption {
                  type = types.bool;
                  default = true;
                };
                global = mkOption {
                  type = types.listOf types.str;
                  default = [ ];
                };
                nameservers = mkOption {
                  type = types.submodule {
                    options.global = mkOption {
                      type = types.listOf types.str;
                      default = [ ];
                    };
                  };
                  default = { };
                };
              };
            };
            default = { };
          };
          log.level = mkOption {
            type = types.str;
            default = "info";
          };
          logtail.enabled = mkOption {
            type = types.bool;
            default = false;
          };
          prefixes.v4 = mkOption {
            type = types.str;
            default = null;
          };
          noise.private_key_path = mkOption {
            type = types.path;
            default = "/var/lib/headscale/noise_private.key";
          };
        };
      };
      default = { };
      description = "Configuration settings for Headscale.";
    };
  };

  config = mkIf cfg.enable {
    environment.systemPackages = [ cfg.package ];

    services.headscale = {
      enable = true;
      package = cfg.package;
      port = cfg.port;
      settings = cfg.settings;
    };

    pepe.core = {
      firewall.openUDP = [ cfg.port ];
      vhost.hosts.${cfg.domain} = {
        locations."/" = {
          host = cfg.host;
          port = cfg.port;
          allowWAN = true;
          proxyWebsockets = true;
          extraConfig = ''
            add_header Strict-Transport-Security "max-age=15552000; includeSubDomains" always;
            proxy_buffering off;
          '';
        };
      };
    };
  };
}