(feature) Add Stage Manager (com.apple.WindowManager) settings as system.defaults.windowmanager

All credits go to @AlexOwl. Their [PR](https://github.com/LnL7/nix-darwin/pull/505)
looked abandonned so I reported their changes and addressed the change
requests.

3 files changed, 80 insertions, 0 deletions

diff --git a/modules/module-list.nix b/modules/module-list.nix
index d6116d9..0b62158 100644
--- a/modules/module-list.nix
+++ b/modules/module-list.nix
@@ -32,6 +32,7 @@
   ./system/defaults/trackpad.nix
   ./system/defaults/universalaccess.nix
   ./system/defaults/ActivityMonitor.nix
+  ./system/defaults/WindowManager.nix
   ./system/etc.nix
   ./system/keyboard.nix
   ./system/launchd.nix
diff --git a/modules/system/defaults-write.nix b/modules/system/defaults-write.nix
index 18be408..827a7d3 100644
--- a/modules/system/defaults-write.nix
+++ b/modules/system/defaults-write.nix
@@ -32,6 +32,7 @@ let
   trackpadBluetooth = defaultsToList "com.apple.driver.AppleBluetoothMultitouch.trackpad" cfg.trackpad;
   universalaccess = defaultsToList "com.apple.universalaccess" cfg.universalaccess;
   ActivityMonitor = defaultsToList "com.apple.ActivityMonitor" cfg.ActivityMonitor;
+  WindowManager = defaultsToList "com.apple.WindowManager" cfg.WindowManager;
   CustomUserPreferences = flatten (mapAttrsToList (name: value: defaultsToList name value) cfg.CustomUserPreferences);
   CustomSystemPreferences = flatten (mapAttrsToList (name: value: defaultsToList name value) cfg.CustomSystemPreferences);
 
@@ -85,6 +86,7 @@ in
         universalaccess
         ActivityMonitor
         CustomUserPreferences
+        WindowManager
       ]
       ''
         # Set defaults
@@ -107,6 +109,7 @@ in
         ${concatStringsSep "\n" universalaccess}
         ${concatStringsSep "\n" ActivityMonitor}
         ${concatStringsSep "\n" CustomUserPreferences}
+        ${concatStringsSep "\n" WindowManager}
 
         ${optionalString (length dock > 0) ''
           # Only restart Dock if current user is logged in
diff --git a/modules/system/defaults/WindowManager.nix b/modules/system/defaults/WindowManager.nix
new file mode 100644
index 0000000..38fbaa3
--- /dev/null
+++ b/modules/system/defaults/WindowManager.nix
@@ -0,0 +1,76 @@
+{ config, lib, ... }:
+
+with lib;
+{
+  options = {
+    system.defaults.WindowManager.GloballyEnabled = mkOption {
+      type = types.nullOr types.bool;
+      default = null;
+      description = ''
+        Enable Stage Manager
+        Stage Manager arranges your recent windows into a single strip for reduced clutter and quick access. Default is false.
+      '';
+    };
+
+    system.defaults.WindowManager.EnableStandardClickToShowDesktop = mkOption {
+      type = types.nullOr types.bool;
+      default = null;
+      description = ''
+        Click wallpaper to reveal desktop
+        Clicking your wallpaper will move all windows out of the way to allow access to your desktop items and widgets. Default is true.
+        false means "Only in Stage Manager"
+        true means "Always"
+      '';
+    };
+
+    system.defaults.WindowManager.AutoHide = mkOption {
+      type = types.nullOr types.bool;
+      default = null;
+      description = ''
+        Auto hide stage strip showing recent apps. Default is false.
+      '';
+    };
+
+    system.defaults.WindowManager.AppWindowGroupingBehavior = mkOption {
+      type = types.nullOr types.bool;
+      default = null;
+      description = ''
+        Grouping strategy when showing windows from an application.
+        false means "One at a time"
+        true means "All at once"
+      '';
+    };
+
+    system.defaults.WindowManager.StandardHideDesktopIcons = mkOption {
+      type = types.nullOr types.bool;
+      default = null;
+      description = ''
+        Hide items on desktop.
+        '';
+    };
+
+    system.defaults.WindowManager.HideDesktop = mkOption {
+      type = types.nullOr types.bool;
+      default = null;
+      description = ''
+        Hide items in Stage Manager.
+      '';
+    };
+
+    system.defaults.WindowManager.StandardHideWidgets = mkOption {
+      type = types.nullOr types.bool;
+      default = null;
+      description = ''
+          Hide widgets on desktop.
+        '';
+    };
+
+    system.defaults.WindowManager.StageManagerHideWidgets = mkOption {
+      type = types.nullOr types.bool;
+      default = null;
+      description = ''
+        Hide widgets in Stage Manager.
+      '';
+    };
+  };
+}