A French movie

[Emperor]

I am looking for a French movie about some man who was a socialist and a toymaker of wooden toys in France in period before WW1 or before WW2. He has a son and a German friend who helps him make toys. German friend take his son to Germany on Christmas eve with his mother. When German friend comes back French police arrest him as suspicion that he is a spy. The son steals some toys from father...In the end there is some diorama of WW1 of wooden soldiers with wooden airplanes and explosions...