nix/os-mods/common/default.nix

{ config
, lib
, pkgs
, inputs
, system
, ...
}: {
  nixpkgs.hostPlatform = lib.mkDefault system;

  nix = {
    gc = {
      automatic = true;
      dates = "weekly";
      options = "--delete-older-than 2w";
      randomizedDelaySec = "45min";
    };
    settings.auto-optimise-store = true;
    package = pkgs.nixFlakes;
    extraOptions = ''
      experimental-features = nix-command flakes
    '';
  };

  home-manager.backupFileExtension = "bak";

  # locale
  time.timeZone = "Europe/Berlin";

  i18n = {
    defaultLocale = "en_US.UTF-8";

    extraLocaleSettings = {
      LANG = "en_US.UTF-8";
      LC_ADDRESS = "de_DE.UTF-8";
      LC_COLLATE = "de_DE.UTF-8";
      LC_CTYPE = "en_US.UTF-8";
      LC_IDENTIFICATION = "de_DE.UTF-8";
      LC_MEASUREMENT = "de_DE.UTF-8";
      LC_MESSAGES = "en_US.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";
    };
  };
  ####################

  security = {
    pki.certificates = [
      (lib.readFile ../../ext/internal-ca.crt)
    ];
    rtkit.enable = true;

    sudo.enable = false;
    sudo-rs = {
      enable = true;
      wheelNeedsPassword = false;
      execWheelOnly = true;
    };
  };

  environment.sessionVariables = {
    EDITOR = "nvim";
  };

  environment.systemPackages = with pkgs; [
    fclones
    curl
    fish
    figlet
    neovim # editor
    nix-alien
    veracrypt
    git
    vim # fallback ed
    wget

    ## MONITORING TOOLS ##
    btop # for CPU, RAM, and Disk monitoring
    iotop # for disk I/O monitoring
    iftop # for network I/O monitoring
  ];

  fileSystems."/etc/nixos" = {
    device = lib.mkDefault "/home/tristand/nix";
    fsType = "none";
    options = [ "bind" ];
  };

  programs = {
    rust-motd = {
      enable = true;
      enableMotdInSSHD = true;
      settings = {
        banner = {
          color = "green";
          command = ''
            ${pkgs.inetutils}/bin/hostname | ${pkgs.figlet}/bin/figlet -f slant
          '';
        };

        uptime = {
          prefix = "Up";
        };

        global = {
          progress_full_character = "=";
          progress_empty_character = "-";
          progress_prefix = "[";
          progress_suffix = "]";
        };

        filesystems = {
          root = "/";
          home = "/home";
        };

        memory.swap_pos = "beside";
        last_login = builtins.listToAttrs (map
          (user: {
            name = user;
            value = 2;
          })
          (builtins.attrNames config.home-manager.users));
      };
      order = [
        "global"
        "banner"
        "uptime"
        "memory"
        "filesystems"
        "last_login"
      ];
    };
    nix-ld.enable = true;
    nix-ld.package = pkgs.nix-ld-rs;
    command-not-found.enable = false;
    nix-index-database.comma.enable = true;

    fish.enable = true;
    gnupg.agent = {
      enable = true;
      # enableSSHSupport = true; # breaks gitea foo
      pinentryPackage = lib.mkForce pkgs.pinentry-qt;
    };
  };

  services = {
    fwupd.enable = true;

    # envfs.enable = true; # not needed due to flake
    timesyncd.enable = false;
    ntp.enable = false;
    ntpd-rs.enable = true;

    openssh = {
      enable = true;
      settings = {
        PasswordAuthentication = false;
        KbdInteractiveAuthentication = false;
        PubKeyAuthentication = true;
      };
      extraConfig = ''
        AllowTcpForwarding yes
        X11Forwarding no
        AllowAgentForwarding no
        AllowStreamLocalForwarding yes
        AuthenticationMethods publickey
      '';
    };

    gvfs.enable = true;
    avahi.enable = true;
    avahi.nssmdns4 = true;
  };

  networking.firewall = {
    extraCommands = ''iptables -t raw -A OUTPUT -p udp -m udp --dport 137 -j CT --helper netbios-ns'';
    allowedTCPPortRanges = [
      {
        from = 22;
        to = 22;
      } # ssh
    ];
  };
}