{ config, lib, ... }:

with lib;

let
  hardDrives = config.numbus.hardware.spindown.list;
  cfg = config.numbus.hardware;
in

{
  config = mkIf (cfg.HddSpindown.enable == true) {
    systemd.services.hd-idle = {
      description = "External HD spin down daemon";
      wantedBy = [ "multi-user.target" ];
      serviceConfig = {
        Type = "simple";
        ExecStart =
          let
            idleTime = toString 1800;
            hardDriveParameter = lib.strings.concatMapStringsSep " " (x: "-a ${x} -i ${idleTime}") hardDrives;
          in
          "${pkgs.hd-idle}/bin/hd-idle -i 0 ${hardDriveParameter}";
      };
    };
  };

  options.numbus = {
    hardware = {
      spindown = {
        enable = mkEnableOption "hard drives spin down when inactive in order to save power.";
        list = mkOption {
          description = "The list of compatible hard drives that will spin down.";
          type = types.listOf types.str;
          default = [];
          example = [ "/dev/disk/by-id/ata_Hitachi_MZVPYEHCO_159Ejz224G0000" "/dev/disk/by-id/ata-WD_159Ejz224G" ];
        };
        optimize = mkOption {
          description = "Optimize services to reduce HDD wakeups when spindown is enabled. Can be set to \"compatible\" to optimize all compatible services, or a list of service names to optimize.";
          type = types.nullOr (types.either (types.enum [ "compatible" ]) (types.listOf types.str));
          default = "compatible";
          example = "[ \"crafty\" \"gitea\" ]";
        };
      };
    };
  };
}