{ lib, pkgs, ... }:

let
  # Adjust this path if you place apps.nix elsewhere in the repo.
  # Best practice: keep it relative to the flake repo so flakes can read it.
  packagesConfPath = ../assets/conf/apps/packages.conf;

  raw = builtins.readFile packagesConfPath;

  # Split into lines, trim whitespace, drop empty lines and comment lines.
  lines =
    let
      all = lib.splitString "\n" raw;
      trimmed = map lib.strings.trim all;
    in
      builtins.filter (l: l != "" && !(lib.hasPrefix "#" l)) trimmed;

  # Resolve a name like:
  #   "wget" -> pkgs.wget
  #   "kdePackages.okular" -> pkgs.kdePackages.okular
  #   "_1password-gui" -> pkgs."_1password-gui"
  resolvePkg = name:
    let
      parts = lib.splitString "." name;
      found = lib.attrByPath parts null pkgs;
    in
      if found == null then
        throw ''
          apps.nix: Package "${name}" from ${toString packagesConfPath} not found in pkgs.
          Only packages available on https://search.nixos.org/packages can be installed.
          Fix the name (or attribute path) and rebuild.
        ''
      else
        found;

  packages = map resolvePkg lines;

in
{
  environment.systemPackages = packages;
}