almost there

extension.ts

@@ -1,14 +1,29 @@
 import { Extension } from "resource:///org/gnome/shell/extensions/extension.js"
-import * as Main from "resource:///org/gnome/shell/ui/main.js"
-import * as MessageTray from "resource:///org/gnome/shell/ui/messageTray.js"
+import Gio from "gi://Gio"
 
-export default class MyExtension extends Extension {
+export default class AutoRotate extends Extension {
+    _listenerId?: number
     enable() {
-        Main.notify(
-            "Simple Notification",
-            "A notification with a title and body"
+        this._listenerId = global.display.connect(
+            "in-fullscreen-changed",
+            () => {
+                const monitors = global.display.get_n_monitors()
+                const isFullscreen =
+                    [...new Array(monitors)].findIndex((_, index) =>
+                        global.display.get_monitor_in_fullscreen(index)
+                    ) != -1
+
+                const { Meta } = imports.gi;
+                const monitorManager = Meta.MonitorManager.;
+				if (isFullscreen) {
+                } else {
+                }
+            }
         )
     }
 
-    disable() {}
+    disable() {
+        if (this._listenerId != null)
+            global.display.disconnect(this._listenerId)
+    }
 }