It's someone's attempt at making a Chess game by if-else branching ALL possible moves, which is going to be impossible due to the fact that there are around 10^120 possible chess moves.
At first I thought that was 10120 and I was like "that's not so bad!" but then I noticed the little ^ and I realized that the number is actually 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,420,000,000,000,000,000,000,690,000,000,000,000,000,000,000,000.
So, yeah, that wouldn't work.