looking for french chess movie

Possible spoilers in my explanation :


I am looking for a French movie, situated in the past, about a genius small not so handsome chess player, who is in love with a high class lady. A dual is organised against another snobby chess player for the lady in the end. (now here are more spoilers!)



He pulls off a weird trick : deliberately touching a piece, seemingly in favour of the other player, but in the end it is a trap for the other party. The movie ends with the chess player early in the morning at a residence in the mountains, he is outside playing against himself with huge pieces, and then throws himself of a rock.

I have been looking for this movie for at least four years now. Any information would be deeply appreciated!