chessica.formats.fen — org.clojars.kingnuscodus/chessica 0.1.1-SNAPSHOT

Functions for querying and writing Forsyth-Edwards Notation data used in reproducing chess positions.

See: https://en.wikipedia.org/wiki/Forsyth%E2%80%93Edwards_Notation

->data clj

(->data fen)

Transforms a FEN string into a map with keys :pos, an 8x8 vector of vectors of piece keywords or nil for spaces where each piece symbol in FEN is keywordized. :turn, the side to move, one of :w or :b :castling, a vector of up to 4 keywordized FEN symbols (:K,:Q etc) can be empty when no side can castle :en-passant, a [row col] vector of the square 'behind' the pawn just having made an initial (2 squares) move if any, or nil :clock, an int (0 or positive) for the half-move clock :move, the move number in the game. The output map can be more easily queried and transformed.

->fen clj

(->fen {:keys [pos turn castling en-passant clock move]})

Transforms a data map (as per the output of ->data) into a FEN string.

->int clj

(->int c)

->num clj

(->num s)

->pos-data clj

(->pos-data fen-pos)

->pos-fen clj

(->pos-fen pos)

->row-fen clj

(->row-fen col)

complete-data clj

(complete-data other-dat-str board)

fen-start clj

kws->str clj

(kws->str kws)

populate clj

(populate pairs completion-dat)

(populate board pairs completion-dat)

Creates a FEN string from a starting board - an 8x8 vovs, pairs of [piece-or-pieces, locations-string] and tailing data (turn to move, castling state etc). Each pair is in a user-friendly format representing cumulative board updates - see update-board. Example:

(populate [[:p "a7 g6 f7 e6 d5 c7 b7 a7"] ;; black pawn structure

        ["krrnq" "g8 f8 a8 e5 c4"]   ;; black king on g8, rooks on 
                                     ;; f8 and a8, and so forth  

        [:P "g5 f2 c2 b2 a3"]        ;; white pawn structure

        ["QKRRBN" "g3 d1 h1 a1 g1 b1"]] ;; white pieces

        "b KQ - 0 40")  ;; FEN string tail: turn to play, etc.

;;=> "r4rk1/ppp2p2/4p1p1/3pn1P1/2q5/P5Q1/1PP2P2/RN1K2BR b KQ - 0 40"

str->castle clj

(str->castle s)

str->ep clj

(str->ep s)

str->kws clj

(str->kws s)

update-board clj

(update-board p-or-ps locs-str board)

Adds/remove/replace a chess piece to one or more locations on a chess board, where p-or-ps is a either a single piece keyword or a string of space-delimited piece-letters (in which case each piece is inserted at its respective location in locs-str) locs-str is a space separated string of chessboard coordinates, e.g. 'a3 b2' and board is an 8x8 vector of vectors of either nil or occupied squares. The updated board is returned. 'piece can be set to nil to remove the content of each square in 'locs-str.