fix(home-manager/k9s): support darwin without XDG (#311)

* fix(home-manager/k9s): k9s on darwin with xdg disabled

k9s expects configuration files on OS X to live in
`~/Library/Application Support/k9s` instead of `~/.config.k9s`. This
commit handles the case where the module is built for a darwin system
with xdg disabled.

* Refactored

- More closely matches the upstream module in home-manager
- Formatted with nixfmt-rfc-style

* Added missing parentheses

Co-authored-by: seth <[email protected]>

---------

Co-authored-by: seth <[email protected]>

modules/home-manager/k9s.nix

@@ -1,23 +1,34 @@
-{ config, lib, ... }:
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
 let
   inherit (config.catppuccin) sources;
 
   cfg = config.programs.k9s.catppuccin;
   enable = cfg.enable && config.programs.k9s.enable;
 
+  # NOTE: On MacOS specifically, k9s expects its configuration to be in
+  # `~/Library/Application Support` when not using XDG
+  enableXdgConfig = !pkgs.stdenv.hostPlatform.isDarwin || config.xdg.enable;
+
   themeName = "catppuccin-${cfg.flavor}" + lib.optionalString cfg.transparent "-transparent";
   themeFile = "${themeName}.yaml";
-  themePath = "/skins/${themeFile}";
+  themePath = "k9s/skins/${themeFile}";
   theme = sources.k9s + "/dist/${themeFile}";
 in
 {
   options.programs.k9s.catppuccin = lib.ctp.mkCatppuccinOpt { name = "k9s"; } // {
     transparent = lib.mkEnableOption "transparent version of flavor";
   };
 
-  config = lib.mkIf enable {
-    xdg.configFile."k9s${themePath}".source = theme;
-
-    programs.k9s.settings.k9s.ui.skin = themeName;
-  };
+  config = lib.mkIf enable (lib.mkMerge [
+    (lib.mkIf (!enableXdgConfig) {
+      home.file."Library/Application Support/${themePath}".source = theme;
+    })
+    (lib.mkIf enableXdgConfig { xdg.configFile.${themePath}.source = theme; })
+    { programs.k9s.settings.k9s.ui.skin = themeName; }
+  ]);
 }