{
  lib,
  config,
  ...
}: let
  configDir = "/var/lib/hass";
  dbUser = "hass";
in {
  options.services.home-assistant = {
    subdomain = lib.mkOption {
      type = lib.types.str;
      description = "subdomain of base domain that home-assistant will be hosted at";
      default = "home-assistant";
    };

    database = lib.mkOption {
      type = lib.types.enum [
        "builtin"
        "postgres"
      ];
      description = "what database do we want to use";
      default = "builtin";
    };

    extensions = {
      sonos = {
        enable = lib.mkEnableOption "enable the sonos plugin";
        port = lib.mkOption {
          type = lib.types.int;
          default = 1400;
          description = "what port to use for sonos discovery";
        };
      };
      jellyfin = {
        enable = lib.mkEnableOption "enable the jellyfin plugin";
      };
    };
  };

  config = lib.mkIf config.services.home-assistant.enable (lib.mkMerge [
    {
      host = {
        reverse_proxy.subdomains.${config.services.home-assistant.subdomain} = {
          target = "http://localhost:${toString config.services.home-assistant.config.http.server_port}";

          websockets.enable = true;
          forwardHeaders.enable = true;

          extraConfig = ''
            add_header Upgrade $http_upgrade;
            add_header Connection \"upgrade\";

            proxy_buffering off;

            proxy_read_timeout 90;
          '';
        };
      };

      services.home-assistant = {
        configDir = configDir;
        extraComponents = [
          "met"
          "radio_browser"
          "isal"
          "zha"
          "webostv"
          "tailscale"
          "syncthing"
          "analytics_insights"
          "unifi"
          "openweathermap"
          "ollama"
        ];
        config = {
          http = {
            server_port = 8123;
            use_x_forwarded_for = true;
            trusted_proxies = ["127.0.0.1" "::1"];
            ip_ban_enabled = true;
            login_attempts_threshold = 10;
          };
          recorder.db_url = "postgresql://@/${dbUser}";
          "automation manual" = [];
          "automation ui" = "!include automations.yaml";
        };
        extraPackages = python3Packages:
          with python3Packages; [
            hassil
            numpy
            gtts
          ];
      };

      # TODO: configure /var/lib/hass/secrets.yaml via sops

      systemd.tmpfiles.rules = [
        "f ${config.services.home-assistant.configDir}/automations.yaml 0755 hass hass"
      ];
    }
    (lib.mkIf (config.services.home-assistant.extensions.sonos.enable) {
      services.home-assistant.extraComponents = ["sonos"];
      networking.firewall.allowedTCPPorts = [
        config.services.home-assistant.extensions.sonos.port
      ];
    })
    (lib.mkIf (config.services.home-assistant.extensions.jellyfin.enable) {
      services.home-assistant.extraComponents = ["jellyfin"];
      # TODO: configure port, address, and login information here
    })
    (lib.mkIf (config.services.home-assistant.database == "postgres") {
      host = {
        postgres = {
          enable = true;
          extraUsers = {
            ${dbUser} = {
              isClient = true;
              createUser = true;
            };
          };
          extraDatabases = {
            ${dbUser} = {
              name = dbUser;
            };
          };
        };
      };

      services.home-assistant = {
        extraPackages = python3Packages:
          with python3Packages; [
            psycopg2
          ];
      };

      systemd.services.home-assistant = {
        requires = [
          config.systemd.services.postgresql.name
        ];
      };
    })
    (lib.mkIf config.host.impermanence.enable {
      assertions = [
        {
          assertion = config.services.home-assistant.configDir == configDir;
          message = "home assistant config directory does not match persistence";
        }
      ];
      environment.persistence."/persist/system/root" = {
        enable = true;
        hideMounts = true;
        directories = [
          {
            directory = configDir;
            user = "hass";
            group = "hass";
          }
        ];
      };
    })
  ]);
}