Add basic theme config

Signed-off-by: Nikolaos Karaolidis <nick@karaolidis.com>

users/common/options/home-manager/matugen/default.nix

@@ -0,0 +1,23 @@
+{ config, pkgs, lib, ... }:
+
+let
+  cfg = config.programs.matugen;
+in
+{
+  # https://github.com/Theaninova/matugen/blob/add-home-manager-module/hm-module.nix
+  options.programs.matugen = with lib; with types; {
+    enable = mkEnableOption "matugen";
+    package = mkPackageOption pkgs "matugen" { };
+    settings = mkOption {
+      type = attrs;
+      description = "Settings to write to config.toml.";
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    home.packages = [ cfg.package ];
+    xdg.configFile."matugen/config.toml".source = lib.mkIf (cfg.settings != null) (
+      (pkgs.formats.toml { }).generate "matugen" cfg.settings
+    );
+  };
+}