# #128 — weekly generation prune: system + Home Manager profiles.
# Policy: drop gens older than 14 days only when they are beyond the
# three most recent *past* generations (current always kept).
{ config, lib, pkgs, ... }:

{
  config = {
    environment.systemPackages = [ pkgs.nomarchy-gen-prune ];

    # Stock nix.gc --delete-older-than has no keep-N floor and would fight
    # this policy. Keep weekly store GC for dead paths only; generation
    # selection is nomarchy-gen-prune's job.
    nix.gc = {
      automatic = lib.mkDefault true;
      dates = lib.mkDefault "weekly";
      # Empty options → collect unreferenced store paths only (no age-based
      # profile generation wipe).
      options = lib.mkDefault "";
    };

    systemd.services.nomarchy-gen-prune = {
      description = "Prune old NixOS and Home Manager generations (14d, keep ≥3 past)";
      serviceConfig = {
        Type = "oneshot";
        ExecStart = "${pkgs.nomarchy-gen-prune}/bin/nomarchy-gen-prune";
      };
      # After the stock store GC timer if both fire weekly.
      after = [ "nix-gc.service" ];
    };

    systemd.timers.nomarchy-gen-prune = {
      description = "Weekly Nix generation prune (Nomarchy #128)";
      wantedBy = [ "timers.target" ];
      timerConfig = {
        OnCalendar = "weekly";
        Persistent = true;
        RandomizedDelaySec = "1h";
      };
    };
  };
}