Work on registration of existing systems to users

app/Policies/SystemPolicy.php

@@ -26,6 +26,18 @@ class SystemPolicy
 		return ($user->isAdmin() || (! $system->exists));
 	}
 
+	/**
+	 * Can the user register this system
+	 *
+	 * @param User $user
+	 * @param System $system
+	 * @return bool
+	 */
+	public function register(User $user,System $system): bool
+	{
+		return ! $system->users->count() || $system->users->has($user);
+	}
+
 	/**
 	 * Determine whether the user can update the model.
 	 *