/** {@inheritDoc} */
 @Override
 public final void showMessage() {
   showMessage(getTurnPhasePriorityMessage(player.getGame()));
   chosenSa = null;
   if (getController()
       .canUndoLastAction()) { // allow undoing with cancel button if can undo last action
     ButtonUtil.update(getOwner(), "OK", "Undo", true, true, true);
   } else { // otherwise allow ending turn with cancel button
     ButtonUtil.update(getOwner(), "OK", "End Turn", true, true, true);
   }
 }