ChessAI

A Javscript chess AI with a simple user interface to challenge it.

State String

A state string is made up of:

64 Chars: Board Pieces
- Start with rank 8, end with rank 1 (from white's perspective)
- Start with file a=1, end with rank h=8
- PNBRQK for white pieces
- pnbrqk for black pieces
- . for empty square
1 Char: Who is to play?
- w or b for who to move next
4 Char Castling ability X
- (only based on 'has stuff moved?' not 'does this cross check')
- 1 if: white can castle queenside
- 1 if: white can castle kingside
- 1 if: black can castle queenside
- 1 if: black can castle kingside
2 Char: En Passant
- xy is (file, rank) of the square for en passant
- eg, after a move e4, this would be set to "53" = e3
- .. if nothing moves
2 Char: Move counter without capture or pawn advance
- 0 Padded if only one char