Soft Sleeper -- when on the train ... how is the meal selections or where to get decent meals?

There is a dinner carriage for long distance trip. You can buy some food there. However, they offer simple Chinese food only. You may take some food of your own as well. If you board from Chengsu, the begining station, the toilet should not be too bad. But the situation become worse if not well maintained during the following trip:-(