]> code.delx.au - gnu-emacs-elpa/blobdiff - chess-uci.el
Optionally allow UCI engines to query a book provided by polyglot.
[gnu-emacs-elpa] / chess-uci.el
index befdaaad94d817fecba6bac350a0322610e4a233..2413cd84d3565c4c7b373ad98cfd9942f5d04275 100644 (file)
 ;; the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 ;; Boston, MA 02111-1307, USA.
 
+;;; Commentary:
+
+;; URL: http://en.wikipedia.org/wiki/Universal_Chess_Interface
+
 ;;; Code:
 
 (require 'chess-common)
+(require 'chess-polyglot)
+
+(defgroup chess-uci nil
+  "Customisations for Chess engines based on the UCI protocol"
+  :group 'chess)
+
+(defcustom chess-uci-polyglot-book-file nil
+  "The path to a polyglot binary opening book file."
+  :group 'chess-uci
+  :type '(choice (const :tag "Not specified" nil) file))
+
+(defvar chess-uci-book nil
+  "A (polyglot) opening book object.
+See `chess-uci-polyglot-book-file' for details on how to enable this.")
 
-(defvar chess-uci-move-regexp "[a-h][1-8][a-h][1-8][nbrq]?"
-  "A regular expression matching a UCI move.")
+(defvar chess-uci-long-algebraic-regexp "\\([a-h][1-8]\\)\\([a-h][1-8]\\)\\([nbrq]\\)?"
+  "A regular expression matching a UCI log algebraic move.")
+
+(defun chess-uci-long-algebraic-to-ply (position move)
+  "Convert the long algebraic notation MOVE for POSITION to a ply."
+  (assert (vectorp position))
+  (assert (stringp move))
+  (let ((case-fold-search nil))
+    (when (string-match chess-uci-long-algebraic-regexp move)
+      (let ((color (chess-pos-side-to-move position))
+           (from (chess-coord-to-index (match-string 1 move)))
+           (to (chess-coord-to-index (match-string 2 move)))
+           (promotion (match-string 3 move)))
+       (apply #'chess-ply-create position nil
+              (if (and (= from (chess-pos-king-index position color))
+                       (= (chess-index-rank from) (chess-index-rank to))
+                       (> (abs (- (chess-index-file from)
+                                  (chess-index-file to))) 1))
+                  (chess-ply-castling-changes
+                   position
+                   (< (- (chess-index-file to) (chess-index-file from)) 0))
+                (nconc (list from to)
+                       (when promotion
+                         (list :promote (upcase (aref promotion 0)))))))))))
+
+(defsubst chess-uci-convert-long-algebraic (move)
+  "Convert long algebraic MOVE to a ply in reference to the engine position.
+If conversion fails, this function fired an 'illegal event."
+  (or (chess-uci-long-algebraic-to-ply (chess-engine-position nil) move)
+      (chess-engine-command nil 'illegal)))
+
+(defvar chess-uci-regexp-alist
+  (list
+   (cons "^id\\s-+name\\s-+\\(.+\\)$"
+        (function
+         (lambda ()
+           (setq-local chess-engine-opponent-name (match-string 1))
+           'once)))
+   (cons (concat "^bestmove\\s-+\\(" chess-uci-long-algebraic-regexp "\\)")
+        (function
+         (lambda ()
+           (funcall chess-engine-response-handler 'move
+                    (chess-uci-convert-long-algebraic (match-string 1)))))))
+  "Patterns matching responses of a standard UCI chess engine.")
 
 (defun chess-uci-position (game)
+  "Convert the current GAME position to a UCI position command string."
   (concat "position fen " (chess-pos-to-fen (chess-game-pos game 0) t)
          " moves " (mapconcat (lambda (ply)
                                 (let ((source (chess-ply-source ply))
          "\n"))
 
 (defun chess-uci-handler (game event &rest args)
+  "Default handler for UCI based engines."
   (unless chess-engine-handling-event
     (cond
+     ((eq event 'initialize)
+      (when chess-uci-polyglot-book-file
+       (unless chess-uci-book
+         (setq chess-uci-book (chess-polyglot-book-open
+                               chess-uci-polyglot-book-file))))
+      (apply #'chess-common-handler game event args))
+
      ((eq event 'move)
       (when (= 1 (chess-game-index game))
        (chess-game-set-tag game "White" chess-full-name)
        (chess-game-set-tag game "Black" chess-engine-opponent-name))
 
-      (chess-engine-send nil (concat (chess-uci-position game) "go\n"))
+      (let ((book-plies (and chess-uci-book (bufferp chess-uci-book)
+                            (buffer-live-p chess-uci-book)
+                            (chess-polyglot-book-plies chess-uci-book
+                                                       (chess-game-pos game)))))
+       (if book-plies
+           (let ((chess-display-handling-event nil))
+             (funcall chess-engine-response-handler 'move (car book-plies)))
+         (chess-engine-send nil (concat (chess-uci-position game) "go\n"))))
+
       (if (chess-game-over-p game)
          (chess-game-set-data game 'active nil)))