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

with lib;
let
  cfg = config.modules.core.kernel;
in {
  options.modules.core.kernel = {
    zswap = mkEnableOption "Enable zswap, a compressed RAM cache for swap pages";
    v4l2 = mkEnableOption "Enable support for v4l2 loopback devices";
  };

  config = mkMerge [
    (mkIf cfg.zswap {
      boot.kernelParams = [
        "zswap.enabled=1"
        "zswap.shrinker_enabled=1"
        "zswap.max_pool_percent=20"
        "zswap.compressor=zstd"
        "zswap.zpool=zsmalloc"
      ];
    })
    (mkIf cfg.v4l2 {
      boot.kernelModules = ["v4l2loopback"];
      boot.extraModulePackages = with config.boot.kernelPackages; [ v4l2loopback ];
    })
  ];
}