nixos-config/modules/home/theme.nix

{
  config,
  pkgs,
  lib,
  ...
}:
let
  cfg = config.myConfig;
in
{
  options.myConfig.theme = lib.mkOption { type = lib.types.str; };

  config = lib.mkMerge [
    (lib.mkIf (cfg.theme == "dark") {
      dconf.settings."org/gnome/desktop/interface".color-scheme = "prefer-dark";

      gtk = {
        enable = true;

        gtk2.configLocation = "${config.xdg.configHome}/gtk-2.0/gtkrc";

        theme.name = "Adwaita-dark";
        theme.package = pkgs.gnome.gnome-themes-extra;

        iconTheme.name = "Papirus-Dark";
        iconTheme.package = pkgs.papirus-icon-theme;

        font.name = "Open Sans";
        font.package = pkgs.open-sans;
      };

      qt = {
        enable = true;
        platformTheme.name = "adwaita";
        style.name = "adwaita-dark";
        style.package = pkgs.adwaita-qt;
      };

      home.pointerCursor = {
        name = "Bibata-Original-Classic";
        package = pkgs.bibata-cursors;
        size = 24;
        gtk.enable = true;
      };
    })

    (lib.mkIf (cfg.theme == "light") {
      dconf.settings."org/gnome/desktop/interface".color-scheme = "prefer-light";

      gtk = {
        enable = true;

        gtk2.configLocation = "${config.xdg.configHome}/gtk-2.0/gtkrc";

        theme.name = "Adwaita";
        theme.package = pkgs.gnome.gnome-themes-extra;

        iconTheme.name = "Papirus";
        iconTheme.package = pkgs.papirus-icon-theme;

        font.name = "Open Sans";
        font.package = pkgs.open-sans;
      };

      qt = {
        enable = true;
        platformTheme.name = "adwaita";
        style.name = "adwaita";
        style.package = pkgs.adwaita-qt;
      };

      home.pointerCursor = {
        name = "Bibata-Original-Ice";
        package = pkgs.bibata-cursors;
        size = 24;
        gtk.enable = true;
      };
    })
  ];
}