{
  config,
  lib,
  pkgs,
  ...
}: let
  inherit (lib) mkIf mkOption types filterAttrs mapAttrsToList;
  cfg = config.homelab.motd;

  # collect services to display
  motd_list =
    mapAttrsToList (_: v: v.motd)
    (filterAttrs (_: v: v ? motd && v.motd != null) config.homelab);

in {
  options.homelab.motd = {
    enable = mkOption {
      type = types.bool;
      default = true;
      description = "enable motd script";
    };
  };

  config = mkIf cfg.enable {
    environment.etc."motd".text = ''
      #!/usr/bin/env bash

      active="\033[1;34m"
      inactive="\033[1;31m"
      headings="\033[0;36m"
      bold="\e[1m"
      reset="\033[0m"

      memory=`free -m | awk 'NR==2{printf "%s/%sMB (%.2f%%)\n", $3,$2,$3*100 / $2 }'`
      uptime=`cat /proc/uptime | cut -f1 -d.`
      up_days=$((uptime/60/60/24))
      up_hours=$((uptime/60/60%24))
      up_mins=$((uptime/60%60))
      up_secs=$((uptime%60))

      printf "$bold Welcome to $(hostname)!$reset\n"
      printf "\n"
      printf "$bold  * %-20s$reset %s\n" "Release" "$PRETTY_NAME"
      printf "$bold  * %-20s$reset %s\n" "Kernel" "$(uname -rs)"
      printf "\n"
      printf "$bold  * %-20s$reset %s\n" "CPU usage" "$LOAD1, $LOAD5, $LOAD15 (1, 5, 15 min)"
      printf "$bold  * %-20s$reset %s\n" "Memory" "$memory"
      printf "$bold  * %-20s$reset %s\n" "System uptime" "$up_days days $up_hours hours $up_mins minutes $up_secs seconds"

      printf "\n"
      printf "$bold Service status$reset\n"

      # --- System Info ---
      default_iface=$(ip route | awk '/default/ {print $5; exit}')
      ip_addr=$(ip -4 addr show "''${default_iface}" | awk '/inet / {print $2}' | cut -d/ -f1)
      nixos_version=$(grep '^VERSION=' /etc/os-release | cut -d'"' -f2 | tr -d '\n')
      kernel_version=$(uname -r)

      # --- Resource Stats ---
      cpu_usage=$(top -bn1 | grep "Cpu(s)" | awk '{print 100 - $8 "%"}')
      mem_total=$(grep MemTotal /proc/meminfo | awk '{print $2}')
      mem_avail=$(grep MemAvailable /proc/meminfo | awk '{print $2}')
      mem_used=$((mem_total - mem_avail))
      mem_percent=$((100 * mem_used / mem_total))
      uptime_fmt=$(uptime -p 2>/dev/null || cat /proc/uptime | awk '{print int($1/3600)"h "int(($1%3600)/60)"m"}')

      echo -e "''${headings}Resources''${reset}"
      echo -e "  CPU Usage: ''${cpu_usage}"
      echo -e "  Memory: ''${mem_percent}% used"
      echo -e "  Uptime: ''${uptime_fmt}"
      echo

      # --- services ---
      echo -e "''${headings}Homelab Services''${reset}"

      ${lib.concatStringsSep "\n" (map (service: ''
          if systemctl list-units --type=service --all | grep -q "${service}"; then
            status=$(systemctl is-active ${service} 2>/dev/null)
            if [ "''${status}" = "active" ]; then
              echo -e "  ''${active}${service}''${reset} - running"
            else
              echo -e "  ''${inactive}${service}''${reset} - not running"
            fi
          else
            echo -e "  ''${inactive}${service}''${reset} - not found"
          fi
        '')
        motd_list)}

      echo
    '';

    environment.etc."motd".mode = "0755";

    programs.bash.interactiveShellInit = ''
      /etc/motd
    '';
  };
}