{ pkgs, lib, config, ... }:
let
  cfg = config.mods.unfree.nvidia;
in {
  options.mods.unfree.nvidia = {
    enable = lib.mkEnableOption {
      default = false;
      description = "enables proprietary nvidia drivers";
    };
    packages = lib.mkOption {
      # default = [ "nvidia-x11" "nvidia-settings" "nvidia-persistenced" ];
      default = [ "nvidia-x11" ];
      description = "unfree packages";
    };
    driver = lib.mkOption {
      default = "stable";
      description = "nvidiaPackages driver kernel package";
    };
  };

  config = lib.mkIf cfg.enable {
    # nixos.wiki/wiki/Nvidia
    hardware.opengl = {
      enable = true;
      driSupport = true;
      driSupport32Bit = true;
    };

    # boot.kernelParams = [ "nvidia.NVreg_PreserveVideoMemoryAllocations=1" ];
    # boot.initrd.kernelModules = [ "nvidia" ];
    services.xserver.videoDrivers = [ "nvidia" "nvidia-dkms" ];

    hardware.nvidia = {
      modesetting.enable = true;

      powerManagement.enable = false;
      powerManagement.finegrained = false;

      open = false;
      nvidiaSettings = false;
      
      package = config.boot.kernelPackages.nvidiaPackages."${cfg.driver}";
      # package = let 
      #   rcu_patch = pkgs.fetchpatch {
      #     url = "https://github.com/gentoo/gentoo/raw/c64caf53/x11-drivers/nvidia-drivers/files/nvidia-drivers-470.223.02-gpl-pfn_valid.patch";
      #     hash = "sha256-eZiQQp2S/asE7MfGvfe6dA/kdCvek9SYa/FFGp24dVg=";
      #   };
      # in config.boot.kernelPackages.nvidiaPackages.mkDriver {
      #     version = "535.154.05";
      #     sha256_64bit = "sha256-fpUGXKprgt6SYRDxSCemGXLrEsIA6GOinp+0eGbqqJg=";
      #     sha256_aarch64 = "sha256-G0/GiObf/BZMkzzET8HQjdIcvCSqB1uhsinro2HLK9k=";
      #     openSha256 = "sha256-wvRdHguGLxS0mR06P5Qi++pDJBCF8pJ8hr4T8O6TJIo=";
      #     settingsSha256 = "sha256-9wqoDEWY4I7weWW05F4igj1Gj9wjHsREFMztfEmqm10=";
      #     persistencedSha256 = "sha256-d0Q3Lk80JqkS1B54Mahu2yY/WocOqFFbZVBh+ToGhaE=";

      #     patches = [ rcu_patch ];
      #  };
    };
  };
}