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

let
  hostName = "wlin001-nixos";
  userName = "zulumann";
  userDescription = "Henrik Lutzmann";
  userDir = "/home/zulumann";
  userEmail = "zulumann_70@gmx.de";
  stateVersion = "24.11";
in

{
  imports = [
    ./hardware-configuration.nix
    ./config
  ];

  # Bootloader
  boot = {
    loader.systemd-boot.enable = true;
    loader.efi.canTouchEfiVariables = true;
    #loader.systemd-boot.consoleMode = "2";
    loader.systemd-boot.editor = false;
    loader.systemd-boot.memtest86.enable = true;

    consoleLogLevel = 3;         # silence ACPI "errors" (default is 4)
    plymouth.enable = true;
    tmp.useTmpfs = true;
    tmp.tmpfsSize = "50%";       # set to auto to dynamically grow 
    tmp.cleanOnBoot = true;

    kernelPackages = pkgs.linuxPackages_latest;
    #kernelPackages = pkgs.linuxKernel.kernels.linux_xanmod;
    # initrd.network.openvpn.enable = true;
    initrd.systemd.enable = true;
  };

  # Enable Kernel same-page merging
  hardware.ksm.enable = true;

  # Enable networking
  networking ={
    networkmanager.enable = true;
    networkmanager.plugins = with pkgs; [ networkmanager-openvpn ];
    usePredictableInterfaceNames = false;
    hostName = "${hostName}";
  };

  # Set your time zone
  time.timeZone = "Europe/Berlin";

  # Select internationalisation properties.
  i18n.defaultLocale = "de_DE.UTF-8";
  i18n.extraLocaleSettings = {
    LC_ADDRESS = "de_DE.UTF-8";
    LC_IDENTIFICATION = "de_DE.UTF-8";
    LC_MEASUREMENT = "de_DE.UTF-8";
    LC_MONETARY = "de_DE.UTF-8";
    LC_NAME = "de_DE.UTF-8";
    LC_NUMERIC = "de_DE.UTF-8";
    LC_PAPER = "de_DE.UTF-8";
    LC_TELEPHONE = "de_DE.UTF-8";
    LC_TIME = "de_DE.UTF-8";
  };

  # Configure console 
  console = {
    enable = true;
    earlySetup = true;
    font = "Lat2-Terminus16";
    packages = with pkgs; [terminus_font];
    keyMap = "de";
    #useXkbConfig = true; # use xkb.options in tty.
  };

  # Define a user account. Dont forget to set a password with passwd.
  users.users."${userName}" = {
    isNormalUser = true;
    description = "${userDescription}";
    extraGroups = [ "networkmanager" "wheel" "audio" "video" ];
    openssh.authorizedKeys.keyFiles = [ /etc/nixos/config/home/ssh/authorized_keys ];
    packages = with pkgs;  [ ];
  };

  # Enable Firmware
  hardware = {
    #enableAllFirmware = true;
    enableRedistributableFirmware = true;
    cpu.amd.updateMicrocode = true;
    #cpu.intel.updateMicrocode = true;
  };

  # Some programs need SUID wrappers, can be configured further or are
  # started in user sessions.
  programs.mtr.enable = true;
  programs.gnupg.agent = {
    enable = true;
    enableSSHSupport = true;
  };

  # Enable ZramSwap
  zramSwap = {
    enable = true;
    priority = 100; 
    memoryPercent = 25;
    algorithm = "zstd";
  };

  # Automatic Upgrades
  system.autoUpgrade = {
    enable = false;
    allowReboot = false;
    channel = "https://channels.nixos.org/nixos-${stateVersion}";
  };

  # NixOS Settings
  documentation.nixos.enable = true;
  nix = {
    gc.automatic = true;
    gc.options = "--delete-older-than 7d";
    optimise.automatic = true;
    optimise.dates = [ "weekly" ];
    settings.auto-optimise-store = true;
    settings.cores = 4;		# maximum number of concurrent tasks during one build
    settings.max-jobs = 4;	# maximum number of jobs that Nix will try to build in parallel
    settings.sandbox = true;	# perform builds in a sandboxed environment
  };

  # Filesystems
  fileSystems."/run" = {
    device = "tmpfs";
    fsType = "tmpfs";  
    options = [ "size=6G" ]; # Adjust based on your preferences and needs
  };

  # Fixed : better to use Dynamic 
  fileSystems."/tmp" = {
    device = "tmpfs";
    fsType = "tmpfs";
    options = [ "size=7G" ];  # Adjust based on your preferences and needs
  };

  # No access time and continuous TRIM for SSD
  fileSystems."/".options = [ "noatime" "discard" ];
  fileSystems."/home".options = [ "noatime" "discard" ];

  fileSystems."${userDir}/VM-Image" = {
    device = "/dev/disk/by-uuid/3b47d34d-618a-4a33-9f65-cde6e0d6467e";
    fsType = "ext4";
    options = [ "discard" "noatime" "nofail" "x-systemd.device-timeout=3" ];
  };

  # List services that you want to enable:
  services = {
    acpid.enable = true;
    ananicy.enable = true;
    #fwupd.enable = true;
    gvfs.enable = true;
    haveged.enable = true;
    preload.enable = true;
    udisks2.enable = true;
  };

  # Enable OpenSSH
  services.openssh = {
    enable = true;
    openFirewall = true;
    settings.PermitRootLogin = "no";
    settings.PasswordAuthentication = false;
  };

  # Enable cron service
  services.cron = {
    enable = true;
    systemCronJobs = [ "@hourly ${userName} ${userDir}/.rsync-backup.sh" ];
  };

  # Enable sound with pipewire
  hardware.pulseaudio.enable = false;
  security.rtkit.enable = true;
  services.pipewire = {
    enable = true;
    alsa.enable = true;
    alsa.support32Bit = true;
    pulse.enable = true;
    jack.enable = true;
    #media-session.enable = true;
  };

  # Enable Avahi
  services.avahi = {
    enable = true;
    openFirewall = true;
    nssmdns4 = true;
    publish = {
      enable = true;
      addresses = true;
      domain = true;
      hinfo = true;
      userServices = true;
      workstation = true;
    };
  };

  # Open ports in the firewall
  # netstat -ntulp
  networking.firewall = {
    enable = false;
    allowPing = true;
    logRefusedConnections = true;
    allowedTCPPorts = [ ];
    allowedUDPPorts = [ ];
    allowedTCPPortRanges = [ ];
    allowedUDPPortRanges = [ ];
  };

  # Copy the NixOS configuration file and link it from the resulting system
  # (/run/current-system/configuration.nix). This is useful in case you
  # accidentally delete configuration.nix.
  system.copySystemConfiguration = true;

  system.stateVersion = "${stateVersion}";

}