{ config, lib, pkgs, ... }:

let cfg = config.sydnix.xbacklight-permissions;
in {
  options.sydnix.xbacklight-permissions = {
    enable =
      lib.mkEnableOption "the user group that is allowed to use xbacklight";
    group = lib.mkOption {
      type = lib.types.str;
      default = "xbacklight";
    };
    paths = lib.mkOption {
      type = with lib.types; listOf str;
      default = [
        "/sys/class/backlight/intel_backlight/brightness"
      ];
    };
  };

  config = lib.mkIf cfg.enable {
    users.groups.${cfg.group} = {};

    systemd.tmpfiles.settings."50-xbacklight" =
      lib.mergeAttrsList
        (builtins.map
          (path: {
            ${path}.z = {
              inherit (cfg) group;
              mode = "0664";
              user = "root";
            };
          })
          cfg.paths);
  };
}