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

let
  #################################
  # Read package list from config file
  #################################
  packagesConfPath = "${flakeRoot}/assets/traveldroid/conf/packages.conf";
  raw = builtins.readFile packagesConfPath;

  rawLines = lib.splitString "\n" raw;

  # Guard against splitting into characters accidentally
  _guard = assert !(builtins.stringLength raw > 1 && builtins.length rawLines == builtins.stringLength raw); true;

  # Clean each line: remove CRs, comments, trim whitespace
  cleanLine = line:
    let
      noCR = lib.replaceStrings [ "\r" ] [ "" ] line;
      noInlineComment = lib.head (lib.splitString "#" noCR);
    in
      lib.strings.trim noInlineComment;

  # Filter out empty lines
  entries = builtins.filter (l: l != "") (map cleanLine rawLines);

  # Resolve attribute paths in pkgs
  resolvePkg = name:
    let
      parts = lib.splitString "." name;
      found = lib.attrByPath parts null pkgs;
    in
      if found == null then
        (throw ''
          packages.nix: package not found in pkgs
          Token          : ${builtins.toJSON name}
          packages.conf  : ${packagesConfPath}
          Hint           : check the attribute name on search.nixos.org/packages
        '')
      else
        found;

  # Final system-wide package list
  packages = builtins.seq _guard (map resolvePkg entries);

in {
  #################################
  # Allow unfree packages globally
  #################################
  nixpkgs.config = { allowUnfree = true; };

  #################################
  # System packages
  #################################
  environment.systemPackages = packages;
}