lyx_mirror/lib/tex/lyxskak.sty

% based on skak.sty
% modified to work with older babel versions
% Bug fixes and comment parsing code by Kayvan Sylvan <kayvan@sylvan.com>
%
\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{lyxskak}

\DeclareOption{tiny}{\AtEndOfClass{\tinyboard}}
\DeclareOption{small}{\AtEndOfClass{\smallboard}}
\DeclareOption{normal}{\AtEndOfClass{\normalboard}}
\DeclareOption{large}{\AtEndOfClass{\largeboard}}
\DeclareOption{notation}{\AtEndOfClass{\notationOn}}
\DeclareOption{mover}{\AtEndOfClass{\showmoverOn}}
\DeclareOption{moveroff}{\AtEndOfClass{\showmoverOff}}
\DeclareOption{notationoff}{\AtEndOfClass{\notationOff}}
\DeclareOption{ps}{\def\ps@on{\True}}
\DeclareOption{psoff}{\def\ps@on{\False}}
\DeclareOption{english}{\AtEndOfClass{\skaklanguage[english]}}
\DeclareOption{styleA}{\AtEndOfClass{\styleA}}
\DeclareOption{styleB}{\AtEndOfClass{\styleB}}
\ExecuteOptions{notation,normal,psoff,english,moveroff,styleB}
\ProcessOptions
%\AtBeginDocument{\skaklanguage{english}}

\RequirePackage{lambda,ifthen,calc}
% Now, we rename the ifthenelse here as skak@ifthenelse and then use that
% this is to co-exist with older babel.sty that redefine ifthenelse!
\let\skak@ifthenelse\ifthenelse
\ps@on{\RequirePackage{pstricks,pst-node}\SpecialCoor%
  \newpsstyle{psskak}{arrowinset=0,nodesep=.25,armA=.75,arrowsize=.2 1,
    linearc=.2,arrowlength=1.25,linewidth=0.04,
    doubleline=true,doublesep=.06}}{}



% list related functions
\def\IsNil#1{#1{\False}{\True}}

\def\Member#1#2#3% ('a -> 'a -> bool) -> 'a -> 'a list -> bool
  {#3{\MemberA{#1}{#2}}{\False}}
\def\MemberA#1#2#3#4%
   {#1{#2}{#3}%
     {\True}%
     {\Member{#1}{#2}{#4}}} 

% Explode: string -> char list
\def\Explode#1{\EqStr{Z}{#1}{\Nil}{\ExplodeA#1Z}}
\def\ExplodeA#1#2Z{\EqStr{Z}{#2}%
  {\Singleton{#1}}%
  {\Cons{#1}{\ExplodeA#2Z}}}

\def\BoolToString#1{% bool -> string
#1{True}{False}}

% the basic manipulation of the board
\def\Set#1#2{% square -> piece -> unit 
\expandafter\xdef\csname#1\endcsname{#2}}
\def\Get#1{% square -> piece
\csname#1\endcsname}

\def\StoreBool#1#2{%
  \expandafter\def\csname#1\endcsname{#2}}
\def\GetBool#1{%
  \csname#1\endcsname}


\def\PieceNames{\Listize[K,Q,R,B,N]}
\def\FileNames{\Listize[a,b,c,d,e,f,g,h]}
\def\RankNames{\Listize[1,2,3,4,5,6,7,8]}

%% what pieces to show
%\def\ShowOnlyList{\Listize[K,Q,R,B,N,P,k,q,r,b,n,p]}

\def\showonly#1{\expandafter\def\csname ShowOnlyList\endcsname{\Listize[#1]}}
\def\showall{\showonly{K,Q,R,B,N,P,k,q,r,b,n,p}}
\showall

\def\showonlywhite{\showonly{K,Q,R,B,N,P}}
\def\showonlyblack{\showonly{k,q,r,b,n,p}}
\def\showonlypawns{\showonly{p,P}}

%%%
\def\TeXifx#1#2#3%
   {#1\def\next{#2}\else\def\next{#3}\fi
    \next}
\def\EqStr#1#2{% % has to be changed
  \TeXif{\if#1#2}}
\def\EqPiece#1#2{\TeXif{\if#1#2}}


\def\RankOf(#1){\Second{#1}}
\def\FileOf(#1){\First{#1}}

\def\EqSquare#1#2{%
  \skak@ifthenelse{\equal{#1}{#2}}{\True}{\False}}

%% is this really necessary????
\def\MySecond(#1#2){#2}
\def\MyFirst(#1#2){#1}

\def\MyEqual#1#2{% string -> string -> bool
  \xdef\arga{#1}\xdef\argb{#2}%
  \TeXif{\ifx\arga\argb }}
%  \skak@ifthenelse{\equal{#1}{#2}}{\True}{\False}}

\def\MyEqualB#1#2#3#4{%
  \skak@ifthenelse{\equal{#1}{#2}}{#3}{#4}}

\def\myrightfile#1#2{% filediscriminator -> square -> bool
  \Member{\MyEqual}{#2}{\File{#1}}}

\def\RightRank(#1){%square -> bool
  \EqStr{\RankDiscriminator}{Z}%
  {\True}%
%  {\EqStr{\RankDiscriminator}{\Second{#1}}}}
%  {\expandafter\EqStr{\RankDiscriminator}{\MySecond(#1)}}}
  {\Member{\MyEqual}{#1}{\Rank{\RankDiscriminator}}}}
\def\RightFile(#1){%square -> bool
  \EqStr{\FileDiscriminator}{Z}%
  {\True}%
  {\Member{\MyEqual}{#1}{\File{\FileDiscriminator}}}}

%  {\myrightfile{\FileDiscriminator}{#1}}}

%  {\expandafter\EqStr{\FileDiscriminator}{\FileOf(#1)}}}
%    {\edef\myhelper{\MyFirst(#1)}\Unlistize{\Explode{#1Z}}%
%     (rf-test\myhelper)\EqStr{\FileDiscriminator}{\myhelper}}}
%%  {(rf-test)\EqStr{\FileDiscriminator}{\MyFirst(#1)}}}


\def\Glue#1#2% 'a -> 'b -> 'ab , eg. a -> 1 -> a1
{#1#2}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%% adding ornaments to a board %%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% usefull when adding ps arrows:
% set@fileangle: from -> to -> angle -> unit
\def\set@fileangle#1#2#3{%
  \expandafter\xdef\csname fileangle.#1.#2\endcsname{#3}}
\def\get@fileangle#1#2{\ifx\csname fileangle.#1.#2\endcsname\relax
  \errmessage{Files #1 and #2 does not belong to a valid knight move}%
  \else \csname fileangle.#1.#2\endcsname\fi}
\def\set@rankangle#1#2#3{%
  \expandafter\xdef\csname rankangle.#1.#2\endcsname{#3}}
\def\get@rankangle#1#2{\ifx\csname rankangle.#1.#2\endcsname\relax%
  \errmessage{Ranks #1 and #2 does not belong to a valid knight move}%
  \else \csname rankangle.#1.#2\endcsname\fi}

\def\testfileangle{fileangles:\get@fileangle{a}{b},\get@fileangle{h}{f}}
\def\testrankangle{rankangles:\get@rankangle{1}{3},\get@rankangle{4}{5}}

% a file to ...
\set@fileangle{a}{b}{0}\set@fileangle{a}{c}{0}
% b file to ...
\set@fileangle{b}{a}{0}\set@fileangle{b}{c}{0}\set@fileangle{b}{d}{0}
% c file to ...
\set@fileangle{c}{a}{180}\set@fileangle{c}{b}{0}
\set@fileangle{c}{d}{0}\set@fileangle{c}{e}{0}
% d file to ...
\set@fileangle{d}{b}{180}\set@fileangle{d}{c}{0}
\set@fileangle{d}{e}{0}\set@fileangle{d}{f}{0}
% e file to ...
\set@fileangle{e}{c}{180}\set@fileangle{e}{d}{0}
\set@fileangle{e}{f}{0}\set@fileangle{e}{g}{0}
% f file to ...
\set@fileangle{f}{d}{180}\set@fileangle{f}{e}{0}
\set@fileangle{f}{g}{0}\set@fileangle{f}{h}{0}
% g file to ...
\set@fileangle{g}{e}{180}\set@fileangle{g}{f}{0}\set@fileangle{g}{h}{0}
% h file to ...
\set@fileangle{h}{f}{180}\set@fileangle{h}{g}{0}

% 1st rank to ...
\set@rankangle{1}{2}{0}\set@rankangle{1}{3}{90}
% 2nd rank to ...
\set@rankangle{2}{1}{0}\set@rankangle{2}{3}{0}\set@rankangle{2}{4}{90}
% 3rd rank to ...
\set@rankangle{3}{1}{270}\set@rankangle{3}{2}{0}
\set@rankangle{3}{4}{0}\set@rankangle{3}{5}{90}
% 4th rank to ...
\set@rankangle{4}{2}{270}\set@rankangle{4}{3}{0}
\set@rankangle{4}{5}{0}\set@rankangle{4}{6}{90}
% 5th rank to ...
\set@rankangle{5}{3}{270}\set@rankangle{5}{4}{0}
\set@rankangle{5}{6}{0}\set@rankangle{5}{7}{90}
% 6th rank to ...
\set@rankangle{6}{4}{270}\set@rankangle{6}{5}{0}
\set@rankangle{6}{7}{0}\set@rankangle{6}{8}{90}
% 7th rank to ...
\set@rankangle{7}{5}{270}\set@rankangle{7}{6}{0}\set@rankangle{7}{8}{0}
% 8th rank to ...
\set@rankangle{8}{6}{270}\set@rankangle{8}{7}{0}

% PSTricks addon that allows hollow arrowheads
\ps@on{%
\edef\pst@arrowtable{\pst@arrowtable,<|-|>}
\def\tx@ArrowTriangleA{ArrowTriangleA }
\def\tx@ArrowTriangleB{ArrowTriangleB }
\@namedef{psas@|>}{% 
  /ArrowTriangleA { CLW dup 3.5 div SLW mul add dup 2 div /w ED mul dup 
    /h ED mul /a ED 
    0 h a sub moveto w h L 0 0 L w neg h L 0 h a sub L 
    gsave 1 setgray fill grestore gsave
    stroke grestore } def 
  \psk@arrowinset \psk@arrowlength \psk@arrowsize
  \tx@ArrowTriangleA}
\@namedef{psas@<|}{%
  /ArrowTriangle { CLW dup 2 div SLW mul add dup 2 div 
    /w ED mul dup /h ED mul /a ED 
    { 0 h T 1 -1 scale } if w neg h moveto 0 0 L w h L w neg a neg
    rlineto w neg a rlineto w 0 rmoveto gsave stroke grestore } def 
  true \psk@arrowinset \psk@arrowlength \psk@arrowsize
  \tx@ArrowTriangleB}
% end of PSTricks addon
}
{}

\newcounter{ps@knightangle} \newcounter{ps@inverse}
\def\printknightmove#1#2{% 
  \setcounter{ps@knightangle}{\get@fileangle{\First#1}{\First#2}+%
    \get@rankangle{\Second#1}{\Second#2} + \value{ps@inverse}}%
  \ncdiagg[style=psskak,angleA=\arabic{ps@knightangle}]{-|>}{#1}{#2}}
 
\def\printarrow#1#2{\ncline[style=psskak]{-|>}{#1}{#2}}

\def\ps@highlightsquare#1{%
  \pscustom[linewidth=.06]{\translate(#1)\psframe(-.5,-.5)(.5,.5)}}

\def\highlight#1{% comma separated list eg, \highlight{a1,b4,d4}
  \Apply{\ps@highlightsquare}{\Listize[#1]}}
%%%%% end of adding ornaments to a board %%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%% support for other languages %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% \uc@king queen rook bishop knight pawn holds the letters
% representinng the pieces in the current language
% \skak@currentPieceNames : char list, holds the current piece names
% \def\skak@pieceToEnglish#1{% string -> string, (pgn(curr. lang) -> pgn(eng))
%   \skak@piece@toEnglish(#1Z)}
\def\skak@piece@toEnglish#1{%
  \EqPiece{#1}{\uc@king}%
  {K}%
  {\EqPiece{#1}{\uc@queen}%
    {Q}%
    {\EqPiece{#1}{\uc@rook}%
      {R}%
      {\EqPiece{#1}{\uc@bishop}%
        {B}%
        {\EqPiece{#1}{\uc@knight}%
          {N}%
          {\errmessage{not a valid piece name in the current language:#1}}}}}}}
%   \EqPiece{Z}{#2}%
%   {}% done
%   {\skak@pgn@toEnglish(#2)}}

\def\skak@englishToEnglish#1{#1}

\def\skak@definepieces#1#2#3#4#5#6{%
  \edef\uc@king{#1}
  \edef\uc@queen{#2}
  \edef\uc@rook{#3}
  \edef\uc@bishop{#4}
  \edef\uc@knight{#5}
  \edef\uc@pawn{#6}}

\def\newskaklanguage#1#2{%
  \expandafter\xdef\csname skaklanguage.#1\endcsname{#2}}

\newcommand{\skaklanguage}[1][english]{%
  \def\currentlanguage{#1}%
  \skak@ifthenelse{\equal{#1}{english}}%
    {\let\skak@pieceToEnglish=\skak@englishToEnglish%
      \def\PieceNames{\Listize[K,Q,R,B,N]}}
    {\edef\temp@lang{\csname skaklanguage.#1\endcsname}
      \expandafter\skak@definepieces\temp@lang%
      \let\skak@pieceToEnglish=\skak@piece@toEnglish%
      \def\PieceNames{%
        \Listize[\uc@king,\uc@queen,\uc@rook,\uc@bishop,\uc@knight]}}}

  
\def\showskaklanguage{%
  (\uc@king)(\uc@queen)(\uc@rook)(\uc@bishop)(\uc@knight)(\uc@pawn)}

%%%%% end of language support %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%% parsing macros %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\def\IsPieceName#1{\Member{\EqPiece}{#1}\PieceNames}
\def\IsFile#1% char -> bool
{\Member{\EqStr}{#1}\FileNames}
\def\IsRank#1% char -> bool
{\Member{\EqStr}{#1}\RankNames}
\def\IsCapture#1% char -> bool
{\EqStr{#1}{x}}
\def\IsPromotion#1% char -> bool
{\EqStr{#1}{=}}
\def\IsDash#1% char -> bool
{\EqStr{#1}{-}}
\def\IsO#1% char -> bool
{\EqStr{#1}{O}}

\def\File#1% file -> square list, eg. a -> [a1,a2,...,a8]
{\Map{\Glue{#1}}{\RankNames}} 
\def\Rank#1% rank -> square list, eg. 1 -> [a1,b1,...,h1]
{\Map{\Twiddle\Glue{#1}}{\FileNames}}


% Compose: ('b -> 'c) -> ('a -> 'b) -> ('a -> c')
% Second:  'a -> 'b  -> 'b
% f: 'a -> unit
% Compose Second f: 'a -> ('a -> 'b -> unit)    
% \def\Apply#1#2% ('a -> unit) -> ('a list -> unit)
% {\Force{\Map{#1}{#2}}}
% \def\Force#1{#1\ForceA{}}
% \def\ForceA#1{#1\Foldr\DoIt{}}
% \def\DoIt#1#2{#1#2}

\def\Sideeffect#1#2#3{% ('a -> unit) -> ('a -> 'b -> unit)
  #1{#2}#3}

\def\Apply#1#2{% ('a -> unit)  -> 'a list -> unit
  \Foldr{\Sideeffect{#1}}{\relax}{#2}}


\def\EmptyBoard%
{\Apply{\Twiddle\Set{E}}{\Rank{1}}
\Apply{\Twiddle\Set{E}}{\Rank{2}}
\Apply{\Twiddle\Set{E}}{\Rank{3}}
\Apply{\Twiddle\Set{E}}{\Rank{4}}
\Apply{\Twiddle\Set{E}}{\Rank{5}}
\Apply{\Twiddle\Set{E}}{\Rank{6}}
\Apply{\Twiddle\Set{E}}{\Rank{7}}
\Apply{\Twiddle\Set{E}}{\Rank{8}}}


\def\FenConvert#1{%
  \EqStr{8}{#1}%
  {EEEEEEEE}%
  {\EqStr{7}{#1}%
    {EEEEEEE}%
    {\EqStr{6}{#1}%
      {EEEEEE}%
      {\EqStr{5}{#1}%
        {EEEEE}%
        {\EqStr{4}{#1}%
          {EEEE}%
          {\EqStr{3}{#1}%
            {EEE}%
            {\EqStr{2}{#1}%
              {EE}%
              {\EqStr{1}{#1}%
                {E}%
                {#1}}}}}}}}}
       

\def\ParseFenRank#1{\ParseFenRankA(#1Z)}
\def\ParseFenRankA(#1#2){%
  \EqStr{Z}{#1}%
  {}%
  {\FenConvert{#1}\ParseFenRankA(#2)}}

\def\SetCheckKing#1#2{% square -> piece -> unit
  \EqStr{K}{#2}%
  {\edef\WhiteKingSquare{#1}}%
  {\EqStr{k}{#2}%
    {\edef\BlackKingSquare{#1}}%
    {}}%
  \Set{#1}{#2}}

\def\InitRank#1#2#3#4#5#6#7#8#9{%
  \SetCheckKing{a#9}{#1}%
  \SetCheckKing{b#9}{#2}%
  \SetCheckKing{c#9}{#3}%
  \SetCheckKing{d#9}{#4}%
  \SetCheckKing{e#9}{#5}%
  \SetCheckKing{f#9}{#6}%
  \SetCheckKing{g#9}{#7}%
  \SetCheckKing{h#9}{#8}}

\def\SetRank#1#2{% rank -> fenrank -> unit
  \edef\pap{\ParseFenRank{#2}}%
  \expandafter\InitRank\pap#1}
 

\def\InitBoard(#1/#2/#3/#4/#5/#6/#7/#8){%
  \SetRank{8}{#1}%
  \SetRank{7}{#2}%
  \SetRank{6}{#3}%
  \SetRank{5}{#4}%
  \SetRank{4}{#5}%
  \SetRank{3}{#6}%
  \SetRank{2}{#7}%
  \SetRank{1}{#8}%
  }

\def\WhiteCastling{-}
\def\BlackCastling{-}

\def\ExtractWhiteCastling#1{\def\tempCastling{-}%
\ExtractWhiteCastlingA(#1Z)%
\edef\WhiteCastling{\tempCastling}}
\def\ExtractWhiteCastlingA(#1#2){%
  \EqStr{Z}{#1}%
  {}%
  {\Or{\EqPiece{K}{#1}}{\EqPiece{Q}{#1}}%
    {\EqStr{-}{\tempCastling}%
      {\edef\tempCastling{#1}\ExtractWhiteCastlingA(#2)}%
      {\edef\tempCastling{\tempCastling#1}}}%
    {\ExtractWhiteCastlingA(#2)}}}

\def\ExtractBlackCastling#1{\def\tmpCastling{-}%
\ExtractBlackCastlingA(#1Z)%
\edef\BlackCastling{\tmpCastling}}
\def\ExtractBlackCastlingA(#1#2){%
  \EqStr{Z}{#1}%
  {}%
  {\Or{\EqPiece{k}{#1}}{\EqPiece{q}{#1}}%
    {\EqStr{-}{\tmpCastling}%
      {\edef\tmpCastling{#1}\ExtractBlackCastlingA(#2)}%
      {\edef\tmpCastling{\tmpCastling#1}}}%
    {\ExtractBlackCastlingA(#2)}}}

\newcounter{halfmove}
\newcounter{move}
\def\fenboard#1{\FenBoard#1)}
\def\FenBoard#1 #2 #3 #4 #5 #6){%
  \InitBoard(#1)%
  \def\WhiteToMove{\EqStr{w}{#2}}%
    \ExtractWhiteCastling{#3}%}
    \ExtractBlackCastling{#3}%}
  \def\EnPassantSquare{#4}%
  \setcounter{halfmove}{#5}%
  \setcounter{move}{#6}}


\newcounter{helpgobble}
\def\PieceToFen#1{%
  \EqPiece{E}{#1}%
  {1}{#1}}

\def\Fen@RawRank#1{\PieceToFen{\Get{a#1}}\PieceToFen{\Get{b#1}}%
    \PieceToFen{\Get{c#1}}\PieceToFen{\Get{d#1}}%
    \PieceToFen{\Get{e#1}}\PieceToFen{\Get{f#1}}%
    \PieceToFen{\Get{g#1}}\PieceToFen{\Get{h#1}}}

\def\PrintCastling{%
  \EqStr{-}{\WhiteCastling}%
  {\BlackCastling}%
  {\WhiteCastling%
    \EqStr{-}{\BlackCastling}%
    {-}%
    {\BlackCastling}}}


\def\Fen@handlenumbers#1#2#3#4#5#6#7#8{\setcounter{helpgobble}{0}%
  \Fen@handleA(#1#2#3#4#5#6#7#8Z)}
\def\Fen@handleA(#1#2){%
  \EqStr{Z}{#1}%
  {\ifnum0=\thehelpgobble%
    \else\edef\temp@rank{\temp@rank\arabic{helpgobble}}\fi}%
  {\EqPiece{1}{#1}%
    {\stepcounter{helpgobble}\Fen@handleA(#2)}%
    {\ifnum0=\thehelpgobble\edef\temp@rank{\temp@rank#1}\Fen@handleA(#2)%
      \else\edef\temp@rank{\temp@rank\arabic{helpgobble}#1}%
      \setcounter{helpgobble}{0}\Fen@handleA(#2)\fi}}}


\def\Fen@Rank#1{\edef\temp@rank{}\edef\temp@rankA{\Fen@RawRank{#1}}%
  \expandafter\Fen@handlenumbers\temp@rankA}

\def\Fen@calculate{%
  \Fen@Rank{8}\edef\temp@board{\temp@rank/}%
  \Fen@Rank{7}\edef\temp@board{\temp@board\temp@rank/}%
  \Fen@Rank{6}\edef\temp@board{\temp@board\temp@rank/}%
  \Fen@Rank{5}\edef\temp@board{\temp@board\temp@rank/}%
  \Fen@Rank{4}\edef\temp@board{\temp@board\temp@rank/}%
  \Fen@Rank{3}\edef\temp@board{\temp@board\temp@rank/}%
  \Fen@Rank{2}\edef\temp@board{\temp@board\temp@rank/}%
  \Fen@Rank{1}\edef\temp@board{\temp@board\temp@rank}%
  \edef\temp@board{\temp@board\space\WhiteToMove{w}{b}}%
  \edef\temp@board{\temp@board\space\PrintCastling\space\EnPassantSquare}%
  \edef\temp@board{\temp@board\space\arabic{halfmove}\space\arabic{move}}}


\def\boardasfen{\Fen@calculate\temp@board} % if someone wants fen in
                                           % their document


%%%%% manipulation of the board state
% the special out-of-bounds square
\Set{Offboard}{X} % note: no piece is named X

\def\EnPassantSquare{-}% updated by ExecuteMove


\def\WhiteToMove{\True}

\def\WhiteKingSquare% unit -> square
{e1}
\def\BlackKingSquare% unit -> square
{e8}
\def\KingSquare#1{% bool -> square
#1\WhiteKingSquare\BlackKingSquare}
\def\SetKingSquare#1#2{% bool -> square -> unit
  #1{\xdef\WhiteKingSquare{#2}}{\xdef\BlackKingSquare{#2}}}


% neighbours of a square
\def\SetNeighbour#1#2#3% direction -> square -> square -> unit, #2's
                       % neighbour in direction #1 is #3
{\expandafter\xdef\csname#1.#2\endcsname{#3}}
\def\GetNeighbour#1#2% direction -> square -> square
{\csname#1.#2\endcsname}
% all the hard work:
% first we deal with the board boarder ;-)
\def\FF#1#2{\SetNeighbour{#1}{#2}{Offboard}}

\def\ForwardDirection#1% bool -> direction; up for white, down for black
{#1{up}{down}}
\def\BackwardDirection#1% bool -> direction
{#1{down}{up}}
\def\LeftDirection#1% bool -> direction
{#1{left}{right}}
\def\RightDirection#1% bool -> direction
{#1{right}{left}}


\Apply{\FF{left}}{\File{a}}
\Apply{\FF{upleft}}{\File{a}}
\Apply{\FF{downleft}}{\File{a}}
\Apply{\FF{right}}{\File{h}}
\Apply{\FF{upright}}{\File{h}}
\Apply{\FF{downright}}{\File{h}}
\Apply{\FF{up}}{\Rank{8}}
\Apply{\FF{upleft}}{\Rank{8}}
\Apply{\FF{upright}}{\Rank{8}}
\Apply{\FF{down}}{\Rank{1}}
\Apply{\FF{downleft}}{\Rank{1}}
\Apply{\FF{downright}}{\Rank{1}}


\def\SetUpNeighbour#1#2#3% direction -> rank -> rank -> unit
{\SetNeighbour{#1}{a#2}{a#3}%
  \SetNeighbour{#1}{b#2}{b#3}%
  \SetNeighbour{#1}{c#2}{c#3}%
  \SetNeighbour{#1}{d#2}{d#3}%
  \SetNeighbour{#1}{e#2}{e#3}%
  \SetNeighbour{#1}{f#2}{f#3}%
  \SetNeighbour{#1}{g#2}{g#3}%
  \SetNeighbour{#1}{h#2}{h#3}}
\let\SetDownNeighbour=\SetUpNeighbour%
\SetUpNeighbour{up}{1}{2}
\SetUpNeighbour{up}{2}{3}
\SetUpNeighbour{up}{3}{4}
\SetUpNeighbour{up}{4}{5}
\SetUpNeighbour{up}{5}{6}
\SetUpNeighbour{up}{6}{7}
\SetUpNeighbour{up}{7}{8}
\SetDownNeighbour{down}{2}{1}
\SetDownNeighbour{down}{3}{2}
\SetDownNeighbour{down}{4}{3}
\SetDownNeighbour{down}{5}{4}
\SetDownNeighbour{down}{6}{5}
\SetDownNeighbour{down}{7}{6}
\SetDownNeighbour{down}{8}{7}



\def\SetUpRightNeighbour#1#2#3% direction -> rank -> rank -> unit
{\SetNeighbour{#1}{a#2}{b#3}%
  \SetNeighbour{#1}{b#2}{c#3}%
  \SetNeighbour{#1}{c#2}{d#3}%
  \SetNeighbour{#1}{d#2}{e#3}%
  \SetNeighbour{#1}{e#2}{f#3}%
  \SetNeighbour{#1}{f#2}{g#3}%
  \SetNeighbour{#1}{g#2}{h#3}%
  \SetNeighbour{#1}{h#2}{Offboard}}
\let\SetDownRightNeighbour=\SetUpRightNeighbour
\SetUpRightNeighbour{upright}{1}{2}
\SetUpRightNeighbour{upright}{2}{3}
\SetUpRightNeighbour{upright}{3}{4}
\SetUpRightNeighbour{upright}{4}{5}
\SetUpRightNeighbour{upright}{5}{6}
\SetUpRightNeighbour{upright}{6}{7}
\SetUpRightNeighbour{upright}{7}{8}
\SetDownRightNeighbour{downright}{2}{1}
\SetDownRightNeighbour{downright}{3}{2}
\SetDownRightNeighbour{downright}{4}{3}
\SetDownRightNeighbour{downright}{5}{4}
\SetDownRightNeighbour{downright}{6}{5}
\SetDownRightNeighbour{downright}{7}{6}
\SetDownRightNeighbour{downright}{8}{7}



\def\SetUpLeftNeighbour#1#2#3% direction -> rank -> rank -> unit
{\SetNeighbour{#1}{a#2}{Offboard}%
  \SetNeighbour{#1}{b#2}{a#3}%
  \SetNeighbour{#1}{c#2}{b#3}%
  \SetNeighbour{#1}{d#2}{c#3}%
  \SetNeighbour{#1}{e#2}{d#3}%
  \SetNeighbour{#1}{f#2}{e#3}%
  \SetNeighbour{#1}{g#2}{f#3}%
  \SetNeighbour{#1}{h#2}{g#3}}
\let\SetDownLeftNeighbour=\SetUpLeftNeighbour
\SetUpLeftNeighbour{upleft}{1}{2}
\SetUpLeftNeighbour{upleft}{2}{3}
\SetUpLeftNeighbour{upleft}{3}{4}
\SetUpLeftNeighbour{upleft}{4}{5}
\SetUpLeftNeighbour{upleft}{5}{6}
\SetUpLeftNeighbour{upleft}{6}{7}
\SetUpLeftNeighbour{upleft}{7}{8}
\SetDownLeftNeighbour{downleft}{2}{1}
\SetDownLeftNeighbour{downleft}{3}{2}
\SetDownLeftNeighbour{downleft}{4}{3}
\SetDownLeftNeighbour{downleft}{5}{4}
\SetDownLeftNeighbour{downleft}{6}{5}
\SetDownLeftNeighbour{downleft}{7}{6}
\SetDownLeftNeighbour{downleft}{8}{7}


\def\SetLeftNeighbour#1#2#3% direction -> file -> file -> unit
{\SetNeighbour{#1}{#21}{#31}%
  \SetNeighbour{#1}{#22}{#32}%
  \SetNeighbour{#1}{#23}{#33}%
  \SetNeighbour{#1}{#24}{#34}%
  \SetNeighbour{#1}{#25}{#35}%
  \SetNeighbour{#1}{#26}{#36}%
  \SetNeighbour{#1}{#27}{#37}%
  \SetNeighbour{#1}{#28}{#38}}
\let\SetRightNeighbour=\SetLeftNeighbour
\SetLeftNeighbour{left}{b}{a}
\SetLeftNeighbour{left}{c}{b}
\SetLeftNeighbour{left}{d}{c}
\SetLeftNeighbour{left}{e}{d}
\SetLeftNeighbour{left}{f}{e}
\SetLeftNeighbour{left}{g}{f}
\SetLeftNeighbour{left}{h}{g}
\SetRightNeighbour{right}{a}{b}
\SetRightNeighbour{right}{b}{c}
\SetRightNeighbour{right}{c}{d}
\SetRightNeighbour{right}{d}{e}
\SetRightNeighbour{right}{e}{f}
\SetRightNeighbour{right}{f}{g}
\SetRightNeighbour{right}{g}{h}



% the knight needs special attention
\def\KnightSquares#1% square -> square list
{\csname#1.knight\endcsname}

\def\SetKnightSquares#1#2% square -> square list -> unit
{\expandafter\def\csname#1.knight\endcsname{#2}}

% a file
\SetKnightSquares{a1}{\Listize[b3,c2]}
\SetKnightSquares{a2}{\Listize[b4,c3,c1]}
\SetKnightSquares{a3}{\Listize[b5,c4,c2,b1]}
\SetKnightSquares{a4}{\Listize[b6,c5,c3,b2]}
\SetKnightSquares{a5}{\Listize[b7,c6,c4,b3]}
\SetKnightSquares{a6}{\Listize[b8,c7,c5,b4]}
\SetKnightSquares{a7}{\Listize[c8,c6,b5]}
\SetKnightSquares{a8}{\Listize[c7,b6]}
% b file
\SetKnightSquares{b1}{\Listize[a3,c3,d2]}
\SetKnightSquares{b2}{\Listize[a4,c4,d3,d1]}
\SetKnightSquares{b3}{\Listize[a5,c5,d4,d2,a1,c1]}
\SetKnightSquares{b4}{\Listize[a6,c6,d5,d3,a2,c2]}
\SetKnightSquares{b5}{\Listize[a7,c7,d6,d4,a3,c3]}
\SetKnightSquares{b6}{\Listize[a8,c8,d7,d5,a5,c5]}
\SetKnightSquares{b7}{\Listize[d8,d6,a5,c5]}
\SetKnightSquares{b8}{\Listize[d7,a6,c6]}
% c file
\SetKnightSquares{c1}{\Listize[a2,b3,d3,e2]}
\SetKnightSquares{c2}{\Listize[a1,a3,b4,d4,e3,e1]}
\SetKnightSquares{c3}{\Listize[a2,a4,b1,b5,d1,d5,e2,e4]}
\SetKnightSquares{c4}{\Listize[a3,a5,b2,b6,d2,d6,e3,e5]}
\SetKnightSquares{c5}{\Listize[a4,a6,b3,b7,d3,d7,e4,e6]}
\SetKnightSquares{c6}{\Listize[a5,a7,b4,b8,d4,d8,e5,e7]}
\SetKnightSquares{c7}{\Listize[a6,a8,b5,d5,e6,e8]}
\SetKnightSquares{c8}{\Listize[a7,b6,d6,e7]}
% d file
\SetKnightSquares{d1}{\Listize[b2,c3,e3,f2]}
\SetKnightSquares{d2}{\Listize[b1,b3,c4,e4,f3,f1]}
\SetKnightSquares{d3}{\Listize[b2,b4,c1,c5,e1,e5,f2,f4]}
\SetKnightSquares{d4}{\Listize[b3,b5,c2,c6,e2,e6,f3,f5]}
\SetKnightSquares{d5}{\Listize[b4,b6,c3,c7,e3,e7,f4,f6]}
\SetKnightSquares{d6}{\Listize[b5,b7,c4,c8,e4,e8,f5,f7]}
\SetKnightSquares{d7}{\Listize[b6,b8,c5,e5,f6,f8]}
\SetKnightSquares{d8}{\Listize[b7,c6,e6,f7]}
% e file
\SetKnightSquares{e1}{\Listize[c2,d3,f3,g2]}
\SetKnightSquares{e2}{\Listize[c1,c3,d4,f4,g3,g1]}
\SetKnightSquares{e3}{\Listize[c2,c4,d1,d5,f1,f5,g2,g4]}
\SetKnightSquares{e4}{\Listize[c3,c5,d2,d6,f2,f6,g3,g5]}
\SetKnightSquares{e5}{\Listize[c4,c6,d3,d7,f3,f7,g4,g6]}
\SetKnightSquares{e6}{\Listize[c5,c7,d4,d8,f4,f8,g5,g7]}
\SetKnightSquares{e7}{\Listize[c6,c8,d5,f5,g6,g8]}
\SetKnightSquares{e8}{\Listize[c7,d6,f6,g7]}
% f file
\SetKnightSquares{f1}{\Listize[d2,e3,g3,h2]}
\SetKnightSquares{f2}{\Listize[d1,d3,e4,g4,h3,h1]}
\SetKnightSquares{f3}{\Listize[d2,d4,e1,e5,g1,g5,h2,h4]}
\SetKnightSquares{f4}{\Listize[d3,d5,e2,e6,g2,g6,h3,h5]}
\SetKnightSquares{f5}{\Listize[d4,d6,e3,e7,g3,g7,h4,h6]}
\SetKnightSquares{f6}{\Listize[d5,d7,e4,e8,g4,g8,h5,h7]}
\SetKnightSquares{f7}{\Listize[d6,d8,e5,g5,h6,h8]}
\SetKnightSquares{f8}{\Listize[d7,e6,g6,h7]}
% g file
\SetKnightSquares{g1}{\Listize[h3,f3,e2]}
\SetKnightSquares{g2}{\Listize[h4,f4,e3,e1]}
\SetKnightSquares{g3}{\Listize[h5,f5,e4,e2,h1,f1]}
\SetKnightSquares{g4}{\Listize[h6,f6,e5,e3,h2,f2]}
\SetKnightSquares{g5}{\Listize[h7,f7,e6,e4,h3,f3]}
\SetKnightSquares{g6}{\Listize[h8,f8,e7,e5,h4,f4]}
\SetKnightSquares{g7}{\Listize[e8,e6,h5,f5]}
\SetKnightSquares{g8}{\Listize[h6,f6,e7]}
% h file
\SetKnightSquares{h1}{\Listize[g3,f2]}
\SetKnightSquares{h2}{\Listize[g4,f3,f1]}
\SetKnightSquares{h3}{\Listize[g5,f4,f2,g1]}
\SetKnightSquares{h4}{\Listize[g6,f5,f3,g2]}
\SetKnightSquares{h5}{\Listize[g7,f6,f4,g3]}
\SetKnightSquares{h6}{\Listize[g8,f7,f5,g4]}
\SetKnightSquares{h7}{\Listize[f8,f6,g5]}
\SetKnightSquares{h8}{\Listize[f7,g6]}


% % finding the neighbours of a square, used when the king moves...
%  \def\Neighbours#1% square -> square list
%  {\Map{\Twiddle\GetNeighbour{#1}}%
%    {\Listize[left,upleft,up,upright,right,downright,down,downleft]}}

% StringToTokens: string -> string list, cut at spaces
\def\StringToTokens#1%
{\skak@ifthenelse{\equal{#1}{}}{\Nil}{\StrToTokens(#1 )}}
\def\StrToTokens (#1 #2){%
  \EqStr{#1}{}% 
    {\Nil}%
    \Cons{#1}{\EqStr{#2}{} {\Nil} {\StrToTokens(#2)}}}

\def\BlackPiece#1% char -> piece
{\EqStr{#1}{K}%
  {k}%
  {\EqStr{#1}{Q}%
    {q}%
    {\EqStr{#1}{R}%
      {r}%
      {\EqStr{#1}{B}%
        {b}%
        {\EqStr{#1}{N}%
          {n}%
          {p}}}}}}

\def\PieceNameToPiece#1#2% piecename -> bool -> piece
{#2{#1}{\BlackPiece{#1}}}

% setting up variables for ParseMove
\def\ParseMoveInit{%
 \gdef\MoveToRank{Z}\gdef\MoveToFile{Z}%
 \gdef\RankDiscriminator{Z}\gdef\FileDiscriminator{Z}%
 \gdef\PieceNameToMove{Z}%
 \gdef\Capture{\False}%
 \gdef\Promotion{\False}\gdef\PromotionPieceName{Z}%
 \gdef\Castling{\False}\gdef\LongCastling{\False}}

\def\ParseMove#1{% string -> unit
  \ParseMoveA(#1)}

\def\ParseMoveA(#1#2){% char -> string -> unit 
  \IsPieceName{#1}%
  {\gdef\PieceNameToMove{\skak@pieceToEnglish{#1}}%
    \gdef\PieceToMove{\PieceNameToPiece{\PieceNameToMove}{\WhiteToMove}}%
    \ParseCoordinates(#2Z)%
    \gdef\MoveTo{\MoveToFile\MoveToRank}}%
  {\IsO{#1}%
    {\def\Castling{\True}%
      \ParseCastling(#2Z)}%
    {\ParseCoordinates(#1#2Z)%
      \gdef\MoveTo{\MoveToFile\MoveToRank}}}}

\def\FirstChar(#1#2){#1}

\def\ParseCoordinates(#1#2){% char -> string -> unit
  \EqStr{Z}{#1}%
  {}% we are done!
  {\IsFile{#1}%
    {\EqStr{\MoveToFile}{Z}%
      {}% first File name in move so nothing to do
      {\xdef\FileDiscriminator{\MoveToFile}}%
      \gdef\MoveToFile{#1}%
      \ParseCoordinates(#2)}%
  {\IsRank{#1}%
    {\EqStr{\MoveToRank}{Z}%
      {}%
      {\gdef\RankDiscriminator{\MoveToRank}}%
      \gdef\MoveToRank{#1}%
      \ParseCoordinates(#2)}%
    {\IsCapture{#1}%
      {\gdef\Capture{\True}%
        \ParseCoordinates(#2)}%
      {\IsPromotion{#1}%
        {\def\Promotion{\True}%
          \gdef\PromotionPieceName{\skak@pieceToEnglish{\FirstChar(#2)}}}}%
      {}% no more information is of interest   
      }}}}

% help for \ParseCastling
\def\ParseCastlingA(#1#2#3){%
  \MyEqualB{#1#2}{-O}%
  {\gdef\LongCastling{\True}}%
  {}}

\def\ParseCastling(-O#1){% strip the first -O, at least Z is left
  \ParseCastlingA(#1VW)}

% \def\ParseCastling(-O#1#2){%
%   \EqStr{#1}{Z}%
%   {}%
%   {\def\LongCastling{\True}}}


% for testing purposes
\def\ShowParseInfo%
{ %MoveTo: \MoveTo
  MoveToRank: \MoveToRank, MoveToFile: \MoveToFile, \\
  RankDiscriminator: \RankDiscriminator, FileDiscriminator:
  \FileDiscriminator, \\ Promotion: \BoolToString{\Promotion},
  PromotionPieceName: \PromotionPieceName
  Capture: \BoolToString{\Capture}, \\
  PieceNameToMove: \PieceNameToMove, \\
  Castling: \BoolToString{\Castling},
  LongCastling: \BoolToString{\LongCastling}}

% castling, with preparation for eg, FisheRandom
%\def\WhiteShortRook{h1}
%\def\WhiteLongRook{a1}
%\def\BlackShortRook{h8}
%\def\WhiteLong
\def\FirstRank#1{% bool -> rank
  #1{1}{8}}
\def\CastleKingFile#1{% bool -> file, LongCastling is used as argument
  #1{c}{g}}
\def\CastleRookToFile#1{%
  #1{d}{f}}
\def\CastleRookFromFile#1{%
  #1{a}{h}}

\def\CastleDone#1{% bool -> unit
  #1{\gdef\WhiteCastling{-}}{\gdef\BlackCastling{-}}}

\def\ExecuteCastling{% relies on \ParseMove
  \stepcounter{halfmove}%
  \gdef\MoveTo{\CastleKingFile{\LongCastling}\FirstRank{\WhiteToMove}}%
  \ExecuteKingMove%
  \gdef\MoveTo{\CastleRookToFile{\LongCastling}\FirstRank{\WhiteToMove}}%
  \DoTheMove{\CastleRookFromFile{\LongCastling}\FirstRank{\WhiteToMove}}%
  \CastleDone{\WhiteToMove}}


%%% after ParseMove has gathered info we find the piece to move
% LookFor looks in one direction, stopping if a non-empty square is
% found
\def\LookFor#1#2#3{% (piece -> bool) -> square -> direction -> square list
  \LookForA{#1}{\GetNeighbour{#3}{#2}}{#3}} % we have to skip the
                                            % first square!!!
\def\LookForA#1#2#3{% (piece -> bool) -> square -> direction -> square list
  #1{\Get{#2}}%
  {\Singleton{#2}}%
  {\EqPiece{E}{\Get{#2}}% empty square => continue in the given direction
    {\LookForA{#1}{\GetNeighbour{#3}{#2}}{#3}}%
    {\Nil}}}


% IsRightPiece is true if a piece matching #1 is on square#2
\def\IsRightPiece#1#2{% piece -> square -> bool
 \EqPiece{#1}{\Get{#2}}}

\def\IsRookQueen#1#2{% bool -> piece -> bool
  \Or{\EqPiece{#2}{\PieceNameToPiece{R}{#1}}}%
  {\EqPiece{#2}{\PieceNameToPiece{Q}{#1}}}%
  }
\def\IsBishopQueen#1#2{% bool -> piece -> bool
  \Or{\EqPiece{#2}{\PieceNameToPiece{B}{#1}}}%
  {\EqPiece{#2}{\PieceNameToPiece{Q}{#1}}}%
  }

% (piece-> bool) -> square -> direction list -> square list
\def\ScanDirections#1#2#3{\Foldr{\Compose\Cat{\LookFor{#1}{#2}}}\Nil{#3}}


% relies on the info gathered by ParseMove
\def\FindPieceSquares#1#2{% bool -> square -> square list 
  \EqPiece{\PieceNameToMove}{R}%
  {\ScanDirections%
    {\EqPiece{\PieceToMove}}{#2}{\Listize[up,down,left,right]}}%
  {\EqPiece{\PieceNameToMove}{B}%
    {\ScanDirections%
      {\EqPiece{\PieceToMove}}{#2}%
      {\Listize[upright,downright,downleft,upleft]}}%
    {\EqPiece{\PieceNameToMove}{Q}%
      {\ScanDirections%
        {\EqPiece{\PieceToMove}}{#2}%
        {\Listize[up,down,left,right,upleft,upright,downleft,downright]}}%
      {\Filter{\IsRightPiece{\PieceToMove}}{\KnightSquares{#2}}}}}}

\def\UniqueMove% bool, if the descriminators <> Z
{\And%
  {\Not{\EqStr{\RankDiscriminator}{Z}}}%
  {\Not{\EqStr{\FileDiscriminator}}{Z}}}

\def\DoTheMove#1{% move the piece from #1 to \MoveToFile\MoveToRank
  \edef\oldpiece{\Get{\MoveToFile\MoveToRank}}%
  \Set{\MoveTo}{\Get{#1}}\Set{#1}{E}%
  \gdef\MoveFrom{#1}}

\def\DoTheMoveList#1{\DoTheMove{\Head{#1}}}

% undoes the move to #1
\def\UndoMove#1{% square -> unit, relies on \oldpiece and \MoveToFile/Rank
\Set{#1}{\Get{\MoveToFile\MoveToRank}}\Set{\MoveToFile\MoveToRank}{\oldpiece}%
\Or{\EqPiece{\PieceToMove}{K}}{\EqPiece{\PieceToMove}{k}}%
  {\SetKingSquare{\WhiteToMove}{#1}}%
  {}}

\def\NoEnemiesFound{% bool
\IsNil{\Cat{\ScanDirections{\IsRookQueen{\Not\WhiteToMove}}%
    {\KingSquare{\WhiteToMove}}{\Listize[up,down,left,right]}}%
  {\ScanDirections{\IsBishopQueen{\Not\WhiteToMove}}%
    {\KingSquare{\WhiteToMove}}%
    {\Listize[upleft,downright,downleft,upright]}}}}

\newboolean{helplegal}

\def\LegalMove#1{% square -> bool, is the move possible to do?
  \DoTheMove{#1}%
  \NoEnemiesFound%
  {\UndoMove{#1}\True}%
  {\UndoMove{#1}\False}}%
%  \skak@ifthenelse{\boolean{helplegal}}{\True}{\False}}
% \def\LegalMove#1{% square -> bool, is the move possible to do?
% %  \edef\oldpiece{\Get{\MoveToFile\MoveToRank}}%
%   \DoTheMove{#1}%
% %  \setboolean{helplegal}{\NoEnemiesFound{true}{false}}%
%   \gdef\HelpLegal{\NoEnemiesFound}
%   \UndoMove{#1}%
%   \HelpLegal}
% %  \skak@ifthenelse{\boolean{helplegal}}{\True}{\False}}

% relies on \ParseMove
\def\TrimMoveList#1{% square -> bool
\gdef\trimhelp{#1}%(
\And{\RightRank(\trimhelp)}{\And{\RightFile(\trimhelp)}{\LegalMove{\trimhelp}}}}
%\And{\RightRank(#1)}{\And{\RightFile(#1)}{\LegalMove{#1}}}}

\def\ExecuteKingMove{% relies on ParseMove, WhiteToMove
  \DoTheMove{\KingSquare{\WhiteToMove}}%
  \SetKingSquare{\WhiteToMove}{\MoveTo}%
  \WhiteToMove%
  {\edef\WhiteCastling{-}}%
  {\edef\BlackCastling{-}}}

% % used by UpdateCastling
% \def\RemoveLongCastling{% relies on \WhiteToMove
%   \WhiteToMove%
%   {\EqStr{KQ}{\WhiteCastling}%
%     {\edef\WhiteCastling{K}}%
%     {\EqStr{Q}{\WhiteCastling}%
%       {\edef\WhiteCastling{-}}
%       {}}}%
%   {\EqStr{kq}{\BlackCastling}%
%     {\edef\BlackCastling{k}}%
%     {\EqStr{q}{\BlackCastling}%
%       {\edef\BlackCastling{-}}%
%       {}}}}

% used by UpdateCastling
\def\RemoveLongCastling{% relies on \WhiteToMove
  \WhiteToMove%
  {\skak@ifthenelse{\equal{KQ}{\WhiteCastling}}%
    {\gdef\WhiteCastling{K}}%
    {\skak@ifthenelse{\equal{Q}{\WhiteCastling}}%
      {\gdef\WhiteCastling{-}}%
      {}}}%
  {\skak@ifthenelse{\equal{kq}{\BlackCastling}}%
      {\gdef\BlackCastling{k}}%
      {\skak@ifthenelse{\equal{q}{\BlackCastling}}%
        {\edef\BlackCastling{-}}%
        {}}}}%

% % used by UpdateCastling
% \def\RemoveShortCastling{% relies on \WhiteToMove
%   \WhiteToMove%
%   {\skak@ifthenelse{\equal{KQ}{\WhiteCastling}}%
%     %\EqStr{KQ}{\WhiteCastling}%
%     {\edef\WhiteCastling{Q}}%
%     {\EqStr{K}{\WhiteCastling}%
%       {\edef\WhiteCastling{-}}%
%       {}}}%
%   {\skak@ifthenelse{\equal{kq}{\BlackCastling}}%
%     %\EqStr{kq}{\BlackCastling}%
%     {\edef\BlackCastling{q}}%
%     {\EqStr{k}{\BlackCastling}%
%       {\edef\BlackCastling{-}}%
%       {}}}}

% used by UpdateCastling
\def\RemoveShortCastling{% relies on \WhiteToMove
  \WhiteToMove%
  {\skak@ifthenelse{\equal{KQ}{\WhiteCastling}}%
    %\EqStr{KQ}{\WhiteCastling}%
    {\gdef\WhiteCastling{Q}}%
    {\skak@ifthenelse{\equal{K}{\WhiteCastling}}
      {\gdef\WhiteCastling{-}}%
      {}}}%
  {\skak@ifthenelse{\equal{kq}{\BlackCastling}}%
    %\EqStr{kq}{\BlackCastling}%
    {\gdef\BlackCastling{q}}%
    {\EqStr{k}{\BlackCastling}%
      {\gdef\BlackCastling{-}}%
      {}}}}

\def\UpdateCastling{% relies on \ParseMove
  \EqPiece{R}{\PieceNameToMove}%
  { \EqSquare{\MoveFrom}{\CastleRookFromFile{\True}\FirstRank{\WhiteToMove}}%
    {\RemoveLongCastling}%
    {\EqSquare{\MoveFrom}{\CastleRookFromFile{\False}\FirstRank{\WhiteToMove}}%
      {\RemoveShortCastling}%
      {}}}%
  {}}% non rook moves will not change the castling possibilities

\def\ExecutePieceMove{% relies on the info gathered by ParseMove
  \Capture{\setcounter{halfmove}{0}}{\stepcounter{halfmove}}%
  \UniqueMove%
  {\DoTheMove{\FileDiscriminator\RankDiscriminator}}%
  {\EqPiece{K}{\PieceNameToMove}%
    {\ExecuteKingMove}%
    {%
%       (\Unlistize{\FindPieceSquares{\WhiteToMove}{\MoveTo}},%
%       \Unlistize{\Filter{\TrimMoveList}%
%         {\FindPieceSquares{\WhiteToMove}{\MoveTo}}})%
      \Apply{\DoTheMove}{\Filter{\TrimMoveList}%
        {\FindPieceSquares{\WhiteToMove}{\MoveTo}}}}%
    }
  \UpdateCastling}

% % for pawn captures and moves
% \newcounter{rankhelp}
% % \def\FromRank{\setcounter{rankhelp}{\MoveToRank}%
% %   \addtocounter{rankhelp}{\WhiteToMove{-1}{1}}
% %   \arabic{rankhelp}}
\def\FromRank{%
  \EqStr{1}{\MoveToRank}%
  {\WhiteToMove{0}{2}}%
  {\EqStr{2}{\MoveToRank}%
    {\WhiteToMove{1}{3}}%
    {\EqStr{3}{\MoveToRank}%
      {\WhiteToMove{2}{4}}%
      {\EqStr{4}{\MoveToRank}%
        {\WhiteToMove{3}{5}}%
        {\EqStr{5}{\MoveToRank}%
          {\WhiteToMove{4}{6}}%
          {\EqStr{6}{\MoveToRank}%
            {\WhiteToMove{5}{7}}%
            {\EqStr{7}{\MoveToRank}%
              {\WhiteToMove{6}{8}}%
              {\EqStr{8}{\MoveToRank}%
                {\WhiteToMove{7}{9}}%
                {}}}}}}}}}
\def\InitialRank{\WhiteToMove{2}{7}}

\def\ExecutePawnMove{% relies on the info obtained by ParseMove
  \setcounter{halfmove}{0}%
  \Capture%
  {\EqPiece{E}{\Get{\MoveTo}}%
    {\Set{\MoveToFile\FromRank}{E}}%
    {}%
    \DoTheMove{\FileDiscriminator\FromRank}%
    \def\EnPassantSquare{-}}%
  {\EqPiece{E}{\Get{\MoveToFile\FromRank}}%
    {\edef\EnPassantSquare{\MoveToFile\FromRank}% two square move
      \DoTheMove{\MoveToFile\InitialRank}}%
    {\DoTheMove{\MoveToFile\FromRank}% one square move
      \def\EnPassantSquare{-}}}%
  \Promotion%
  {\Set{\MoveTo}{\PieceNameToPiece{\PromotionPieceName}{\WhiteToMove}}}%
  {}}


\def\MakeMove#1{% string -> unit
%  (In MakeMove: WhiteToMove \BoolToString\WhiteToMove)
  \ParseMoveInit%
  \ParseMove{#1}%
  \EqPiece{Z}{\PieceNameToMove}%
  {\Castling%
    {\gdef\EnPassantSquare{-}\ExecuteCastling}%
    {\ExecutePawnMove}}%
  {\gdef\EnPassantSquare{-}%
    \ExecutePieceMove}%
  \WhiteToMove%
  {\gdef\WhiteToMove{\False}}%
  {\gdef\WhiteToMove{\True}\addtocounter{move}{1}}%
%(End MakeMove: WhiteToMove \BoolToString\WhiteToMove)
  }

% debugging aid
%\def\MakeMove#1{#1}

\def\mainline{\begingroup\catcode`\#=12 \@mainline}
\def\@mainline#1{\endgroup\gdef\NumberNext{\True}%
  \Mainline(#1 Z ){\mainlinestyle\typeset@A{#1}}}

\def\hidemoves{\begingroup\catcode`\#=12 \@hidemoves}
\def\@hidemoves#1{\endgroup\def\NumberNext{\True}%
  \Mainline(#1 Z )}


\newcounter{helpnumber}
\newcounter{helpnumberMove}
% \def\EatNumber#1{\setcounter{helpnumber}{0}\EatNumberA(#1Z)%
%   \skak@ifthenelse{\value{move}=\value{helpnumber}}%
%     {\def\NumberOK{\True}}%
%     {\def\NumberOK{\False}}}%
\def\EatNumber#1{%
  \setcounter{helpnumberMove}{\arabic{move}}%
  \setcounter{helpnumber}{0}\EatNumberA(#1WXYZ)%
  \skak@ifthenelse{\value{helpnumberMove}=\value{helpnumber}}%
    {\gdef\NumberOK{\True}}%
    {\gdef\NumberOK{\False}}}%
\def\EatNumberA(#1.#2){%
  \setcounter{helpnumber}{#1}%
  \LookForMove(.#2)% sets \ExpectedColur and \CurrentMove
  }

\def\LookForMove(#1#2#3#4){%
  \EqStr{.}{#2}% ... after the move number
  {\gdef\ExpectedColour{\False}%
    \HandleMove(#4)}%
  {\gdef\ExpectedColour{\True}%
    \HandleMove(#2#3#4)}}%

\def\HandleMove(#1XYZ){% executes a move if one is found
  \EqStr{W}{#1}%
  {}%
  {\StripMove(#1)}}
\def\StripMove(#1W){% the execution of a move like 1.e4
  \MakeMoveMainline{#1}}

\def\MakeMoveMainline#1{%
    {\ExpectedColour%
      {\WhiteToMove%
        {\MakeMove{#1}%
          \gdef\ExpectedColour{\False}}%
        {\errmessage{mainline: black, not white, to move}}}%
      {\WhiteToMove%
        {\errmessage{mainline: white, not black, to move}}%
        {\MakeMove{#1}\gdef\NumberNext{\True}}}}}
  

\def\Mainline(#1 #2){%
  \EqStr{Z}{#1}%
  {\EqStr{Z}{#2}{}{\Mainline(#2)}}%
  {\EqStr{[}{#1}%
    {\typeset@eatcomment#1#2WXWX}%
    {\NumberNext%
      {\EatNumber{#1}% sets \NumberOK, \ExpectedColour
                                % executes a move not separated from the 
                                % number with a space, eg, 1.e4
        \NumberOK%
        {\gdef\NumberNext{\False}%
          \Mainline(#2)}%
        {\errmessage{mainline: not the correct move number}}}%
      {\MakeMoveMainline{#1}%
        \Mainline(#2)}}}}
\def\typeset@eatcomment[#1]#2WXWX{\Mainline(#2)}

%%%%% typesetting
%%% figurine notation
%\input{fig1\@ptsize.clo}
\newcommand{\skakfamily}{\usefont{U}{skak}{m}{n}}
\DeclareTextFontCommand{\textskak}{\skakfamily}

\def\liftfig#1{\textskak{#1}}


\def\styleA@opentypesetting{}
\def\styleA@closetypesetting{}
\def\styleA@whiteopen{.}
\def\styleA@blackopen{. -}
\def\styleA@beforenumber{}
\def\styleA@beforewhite{ }
\def\styleA@afterwhite{}
\def\styleA@beforeblack{, }
\def\styleA@afterblack{ }

\def\styleA{%
\let\opentypesetting=\styleA@opentypesetting
\let\closetypesetting=\styleA@closetypesetting
\let\whiteopen=\styleA@whiteopen
\let\blackopen=\styleA@blackopen
\let\beforenumber=\styleA@beforenumber
\let\beforewhite=\styleA@beforewhite
\let\afterwhite=\styleA@afterwhite
\let\beforeblack=\styleA@beforeblack
\let\afterblack=\styleA@afterblack
}
%%%% the default style
\styleA

\def\styleB@opentypesetting{}
\def\styleB@closetypesetting{}
\def\styleB@whiteopen{ }
\def\styleB@blackopen{\ldots}
\def\styleB@beforenumber{}
\def\styleB@beforewhite{}
\def\styleB@afterwhite{ }
\def\styleB@beforeblack{}
\def\styleB@afterblack{ }

\def\styleB{%
\let\opentypesetting=\styleB@opentypesetting
\let\closetypesetting=\styleB@closetypesetting
\let\whiteopen=\styleB@whiteopen
\let\blackopen=\styleB@blackopen
\let\beforenumber=\styleB@beforenumber
\let\beforewhite=\styleB@beforewhite
\let\afterwhite=\styleB@afterwhite
\let\beforeblack=\styleB@beforeblack
\let\afterblack=\styleB@afterblack
}

\def\styleC@opentypesetting{%
  \begin{tabbing}%
    \hspace{.2\linewidth}\=\hspace{.2\linewidth}\=%
    \hspace{.2\linewidth}\= \kill}
\def\styleC@closetypesetting{\end{tabbing}}
\def\styleC@whiteopen{}
\def\styleC@blackopen{\>\ldots}
\def\styleC@beforenumber{\>}
\def\styleC@beforewhite{\>}
\def\styleC@afterwhite{}
\def\styleC@beforeblack{\>}
\def\styleC@afterblack{\\}

\def\styleC{%
\let\opentypesetting=\styleC@opentypesetting
\let\closetypesetting=\styleC@closetypesetting
\let\whiteopen=\styleC@whiteopen
\let\blackopen=\styleC@blackopen
\let\beforenumber=\styleC@beforenumber
\let\beforewhite=\styleC@beforewhite
\let\afterwhite=\styleC@afterwhite
\let\beforeblack=\styleC@beforeblack
\let\afterblack=\styleC@afterblack
}



\def\mainlinestyle{\bfseries}%\let\Fig=\Figb}% could also contain
                                           % definitions of the 
                                % various style options
\def\variationstyle{}%\let\Fig=\Fign}   % as with mainlinestyle


\def\typeset@number#1{\TypeSetAfterBlack{\afterblack}{}%
  \gdef\TypeSetAfterBlack{\True}%
  \beforenumber\typeset@numberA(#1WXYZ)}% 22: -> 22\?open
\def\typeset@numberA(#1.#2){%
  #1\typeset@numberHandlePeriods(.#2)}
\def\typeset@numberHandlePeriods(#1#2#3#4){%
  \EqStr{.}{#2}% ... after the number
  {\blackopen\gdef\TypeSetColour{\False}\gdef\TypeSetAfterWhite{\False}%
    \typeset@numberHandleMove(#4)}%
  {\whiteopen\gdef\TypeSetColour{\True}\gdef\TypeSetAfterWhite{\True}%
    \typeset@numberHandleMove(#2#3#4)}}
\def\typeset@numberHandleMove(#1XYZ){%
  \EqStr{W}{#1}%
  {}%
  {\typeset@numberStripMove(#1)}}
\def\typeset@numberStripMove(#1W){%
  \typeset@A@move{#1}}
  
\def\typeset@A@move#1{%
  \TypeSetColour%
  {\beforewhite\mbox{\typeset@A@moveA(#1Z)}\gdef\TypeSetColour{\False}}%
  {\TypeSetAfterWhite{\afterwhite}{}%
    \beforeblack\mbox{\typeset@A@moveA(#1Z)}%
    \gdef\TypeSetColour{\True}\gdef\TypeSetNumberNext{\True}}}
\def\typeset@A@moveA(#1#2){%
  \EqStr{Z}{#1}%
  {}%
  {\IsPieceName{#1}%
    {\xdef\temp@piece{\skak@pieceToEnglish{#1}}%
      \expandafter\liftfig\temp@piece}%
    {\EqStr{=}{#1}%
      {}%
      {\EqStr{x}{#1}%
        {\ensuremath{\!\!\:\times\!\!\;}}%
        {\EqStr{+}{#1}%
          {\ensuremath{\dagger}}%
          {#1}}}}%
    \typeset@A@moveA(#2)}}


\def\commentstyle{\mdseries}% How embedded comments are typeset
\def\typeset@A#1{\gdef\TypeSetNumberNext{\True}%
  \gdef\TypeSetAfterBlack{\False}\opentypesetting\typeset@AA(#1 Z )%
  \closetypesetting}
\def\typeset@AA(#1 #2){%
  \EqStr{Z}{#1}%
  {\EqStr{Z}{#2}{}{\typeset@AA(#2)}}%
  {\EqStr{[}{#1}%
    {\typeset@printcomment#1#2WXWX}%
    {{\TypeSetNumberNext%
      {\typeset@number{#1}% sets \TypeSetColour
        \gdef\TypeSetNumberNext{\False}%
        \typeset@AA(#2)}%
      {\typeset@A@move{#1}%
        \typeset@AA(#2)}}}}}
\def\typeset@printcomment[#1]#2WXWX{%
  \closetypesetting%
  {\ }{\commentstyle{#1}}%
  \opentypesetting\typeset@AA(#2)}

\def\variation{\begingroup\catcode`\#=12 \@variation}
\def\@variation#1{\endgroup{\variationstyle\typeset@A{#1}}}

% typesetting moves with out move number
\def\wmove{\begingroup\catcode`\#=12 \@wmove}
\def\@wmove#1{\endgroup{\variationstyle\typeset@A@moveA(#1Z)}}
\def\bmove{\begingroup\catcode`\#=12 \@bmove}
\def\@bmove#1{\endgroup{\variationstyle\ldots\typeset@A@moveA(#1Z)}}

%%%
% printing of the board
\newlength{\squarelength}
\newlength{\showlength}
\newlength{\ranklift}

\def\setup@showboard#1{\font\Skak=skak#1%
  \setlength{\squarelength}{#1pt}%
  % ps setup
  \ps@on{\psset{unit=\the\squarelength}
    \edef\ps@squarecenter{(-.5,.5)}}
  {}
  \notationfont\setlength{\ranklift}{.5\squarelength-.8ex}\normalsize}



\def\tinyboard{\font\notationfont=cmss6\setup@showboard{10}}
\def\smallboard{\font\notationfont=cmss8\setup@showboard{15}}
\def\normalboard{\font\notationfont=cmss10\setup@showboard{20}}
\def\largeboard{\font\notationfont=cmss12\setup@showboard{30}}

% the default
\normalboard

\def\ToggleWhiteSquare{%
  \WhiteSquare{\def\WhiteSquare{\False}}{\def\WhiteSquare{\True}}}

\def\WhiteSquarePiece#1{%
  \EqPiece{E}{#1}{0}{#1}}

\def\BlackSquarePiece#1{%
  \EqPiece{E}{#1}{Z}%
  {\EqPiece{P}{#1}{O}%
    {\EqPiece{p}{#1}{o}%
      {\EqPiece{R}{#1}{S}%
        {\EqPiece{r}{#1}{s}%
          {\EqPiece{N}{#1}{M}%
            {\EqPiece{n}{#1}{m}%
              {\EqPiece{B}{#1}{A}%
                {\EqPiece{b}{#1}{a}%
                  {\EqPiece{Q}{#1}{L}%
                    {\EqPiece{q}{#1}{l}%
                      {\EqPiece{K}{#1}{J}{j}}}}}}}}}}}}}
                          
\def\FilterShowOnly#1{% piece -> piece, shows only the pieces in
                      % ShowOnlyList
  \Member{\EqStr}{#1}{\ShowOnlyList}%
  {#1}{E}}


\def\Showchar#1{% square -> drawn square
  \WhiteSquare%
  {\WhiteSquarePiece{\Compose\FilterShowOnly\Get{#1}}}%
  {\BlackSquarePiece{\Compose\FilterShowOnly\Get{#1}}}%
  \ToggleWhiteSquare%
  % ps stuff
  \ps@on{\expandafter\pnode\ps@squarecenter{#1}}{}}
  
\def\Showrank#1{% rank -> drawn rank
\Skak\Apply{\Showchar}{\Rank{#1}}}

\def\ShowrankInverse#1{% rank -> drawn rank
  \Skak\Apply{\Showchar}{\Reverse{\Rank{#1}}}}
%  \Skak\Apply{\Showchar}{\Rank{#1}}}

\def\ShowMoverWhiteNormal{\pscustom{\translate(h1)
\psline{->}(1,0.25)(1,0.8)%
\psframe(0.84,-0.16)(1.16,0.16)}}

\def\ShowMoverBlackNormal{%
  \pscustom[fillstyle=solid,fillcolor=gray]{\translate(h8)%
  \psline{->}(1,-0.25)(1,-0.8)%
  \psframe(0.84,-0.16)(1.16,0.16)}}

\def\ShowMoverWhiteInverse{\pscustom{\translate(a1)
\psline{->}(1,-0.25)(1,-0.8)%
\psframe(0.84,-0.16)(1.16,0.16)}}

\def\ShowMoverBlackInverse{%
  \pscustom[fillstyle=solid,fillcolor=gray]{\translate(a8)%
  \psline{->}(1,0.25)(1,0.8)%
  \psframe(0.84,-0.16)(1.16,0.16)}}



\def\show@board{%
  \def\WhiteSquare{\True}
  \vbox{\offinterlineskip
   \hrule height1pt 
   \hbox{\vrule width1pt
         \vbox{\hbox{\Showrank{8}}\ToggleWhiteSquare
               \hbox{\Showrank{7}}\ToggleWhiteSquare
               \hbox{\Showrank{6}}\ToggleWhiteSquare
               \hbox{\Showrank{5}}\ToggleWhiteSquare
               \hbox{\Showrank{4}}\ToggleWhiteSquare
               \hbox{\Showrank{3}}\ToggleWhiteSquare
               \hbox{\Showrank{2}}\ToggleWhiteSquare
               \hbox{\Showrank{1}}}%
         \vrule width1pt}
   \hrule height1pt}
 \setcounter{ps@inverse}{0}
 \ShowMover
 {\WhiteToMove
   {\ShowMoverWhiteNormal}
   {\ShowMoverBlackNormal}}
 {}
}

\def\show@board@inverse{%
  \def\WhiteSquare{\True}
  \vbox{\offinterlineskip
   \hrule height1pt
   \hbox{\vrule width1pt
         \vbox{\hbox{\ShowrankInverse{1}}\ToggleWhiteSquare
               \hbox{\ShowrankInverse{2}}\ToggleWhiteSquare
               \hbox{\ShowrankInverse{3}}\ToggleWhiteSquare
               \hbox{\ShowrankInverse{4}}\ToggleWhiteSquare
               \hbox{\ShowrankInverse{5}}\ToggleWhiteSquare
               \hbox{\ShowrankInverse{6}}\ToggleWhiteSquare
               \hbox{\ShowrankInverse{7}}\ToggleWhiteSquare
               \hbox{\ShowrankInverse{8}}}%
         \vrule width1pt}
   \hrule height1pt}
 \setcounter{ps@inverse}{180}
 \ShowMover
 {\WhiteToMove
   {\ShowMoverWhiteInverse}
   {\ShowMoverBlackInverse}}
 {}
}

\def\ShowrankNumber#1{%
\makebox[0pt][r]{%
  \raisebox{\ranklift}[0cm][0cm]{%
    \makebox[\squarelength][r]{\notationfont#1\hspace*{.1\squarelength}}}}}

\def\ShowrankWithNumber#1{\ShowrankNumber{#1}%
\vrule width1pt \Showrank{#1}\vrule width1pt}

\def\ShowrankInverseWithNumber#1{\ShowrankNumber{#1}%
  \vrule width1pt\ShowrankInverse{#1}\vrule width1pt}


\def\Showfile#1{\hbox to \squarelength{\hfil\notationfont#1\hfil}}
\def\Showfiles{\hfil\Showfile{a}\Showfile{b}\Showfile{c}\Showfile{d}%
  \Showfile{e}\Showfile{f}\Showfile{g}\Showfile{h}\hfil}
\def\Showfiles@inverse{\hfil\Showfile{h}\Showfile{g}\Showfile{f}\Showfile{e}%
  \Showfile{d}\Showfile{c}\Showfile{b}\Showfile{a}\hfil}

\def\show@board@notation{%
  \def\WhiteSquare{\True}%
  \vbox{\offinterlineskip%
    \hrule height1pt 
    \hbox{\ShowrankWithNumber{8}}\ToggleWhiteSquare
    \hbox{\ShowrankWithNumber{7}}\ToggleWhiteSquare
    \hbox{\ShowrankWithNumber{6}}\ToggleWhiteSquare
    \hbox{\ShowrankWithNumber{5}}\ToggleWhiteSquare
    \hbox{\ShowrankWithNumber{4}}\ToggleWhiteSquare
    \hbox{\ShowrankWithNumber{3}}\ToggleWhiteSquare
    \hbox{\ShowrankWithNumber{2}}\ToggleWhiteSquare
    \hbox{\ShowrankWithNumber{1}}\ToggleWhiteSquare
    \hrule height1pt
    \vspace*{.1\squarelength}
    \hbox{\Showfiles}}
   \setcounter{ps@inverse}{0}
 \ShowMover
 {\WhiteToMove
   {\ShowMoverWhiteNormal}
   {\ShowMoverBlackNormal}}
 {}
}

\def\show@board@notation@inverse{%
  \def\WhiteSquare{\True}%
  \vbox{\offinterlineskip%
    \hrule height1pt 
    \hbox{\ShowrankInverseWithNumber{1}}\ToggleWhiteSquare
    \hbox{\ShowrankInverseWithNumber{2}}\ToggleWhiteSquare
    \hbox{\ShowrankInverseWithNumber{3}}\ToggleWhiteSquare
    \hbox{\ShowrankInverseWithNumber{4}}\ToggleWhiteSquare
    \hbox{\ShowrankInverseWithNumber{5}}\ToggleWhiteSquare
    \hbox{\ShowrankInverseWithNumber{6}}\ToggleWhiteSquare
    \hbox{\ShowrankInverseWithNumber{7}}\ToggleWhiteSquare
    \hbox{\ShowrankInverseWithNumber{8}}\ToggleWhiteSquare
    \hrule height1pt
    \vspace*{.1\squarelength}
    \hbox{\Showfiles@inverse}}
   \setcounter{ps@inverse}{180}
 \ShowMover
 {\WhiteToMove
   {\ShowMoverWhiteInverse}
   {\ShowMoverBlackInverse}}
 {}
}

% on the fly configuration
\def\notationOn{\let\showboard=\show@board@notation%
  \let\showinverseboard=\show@board@notation@inverse}
\def\notationOff{\let\showboard=\show@board%
  \let\showinverseboard=\show@board@inverse}

\def\showmoverOn{\def\ShowMover{\True}}
\def\showmoverOff{\def\ShowMover{\False}}


\def\newgame{%
\fenboard{rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1}}


%%%% storing and loading of games
\newtoks\store@toks
\def\savegame#1{% writes the board as fen to #1.fen
  \newwrite\skakstore%
  \immediate\openout\skakstore=#1.fen%
  \Fen@calculate%
  \immediate\write\skakstore{\temp@board}%
  \immediate\closeout\skakstore}

% loading a board from a fen file is also possible
% the file #1.fen should contain nothing but a fen of
% a game
\def\loadgame#1{%
  \def\load@read{}%
  \newread\load@in%
  \openin\load@in=#1.fen\relax%
  \read\load@in to \load@read%
  \closein\load@in%
  \expandafter\FenBoard\load@read)}

%%% temporary storing of a game position, without resorting to files
% \def\storegame#1{\Fen@calculate%
%   \def#1{\temp@board}}
% \def\restoregame#1{\expandafter\FenBoard#1)}
\def\storegame#1{\Fen@calculate%
  \expandafter\xdef\csname chessgame.#1\endcsname{\temp@board}}
\def\restoregame#1{%
  \edef\restore@temp{\csname chessgame.#1\endcsname}
  \expandafter\FenBoard\restore@temp)}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Added in support of the chess.layout by Kayvan Sylvan <kayvan@sylvan.com>
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%% Modified routines from skak.sty
%
\def\lyxprintarrow#1{\lyxprintarrow@#1@\vspace*{-1\parskip}}
\def\lyxprintarrow@#1->#2@{\ncline[style=psskak]{-|>}{#1}{#2}}

\def\lyxknightmove#1{\lyxknightmove@#1@\vspace*{-1\parskip}}
\def\lyxknightmove@#1->#2@{%
  \setcounter{ps@knightangle}{\get@fileangle{\First#1}{\First#2}+%
    \get@rankangle{\Second#1}{\Second#2} + \value{ps@inverse}}%
  \ncdiagg[style=psskak,angleA=\arabic{ps@knightangle}]{-|>}{#1}{#2}}

\def\lyxhighlight#1{\highlight{#1}\vspace*{-1\parskip}}

%%% Variation indent (You can set this in your preamble)
%
\newlength{\lyxvarindent}
\setlength{\lyxvarindent}{0.15in}

\newlength{\lyxvar@ll}% temporary for storing line length in variations

%%% lyxvariation{....} - Indented paragraph of variation moves, typeset
%%% in the normal fashion (styleB).
%
\def\lyxvariation[#1]#2{%
  %\setlength{\lyxvar@ll}{\textwidth}%
  \setlength{\lyxvar@ll}{\columnwidth}%
  \addtolength{\lyxvar@ll}{-#1\lyxvarindent}%
  \hspace*{#1\lyxvarindent}\parbox{\lyxvar@ll}{\variation{#2}}}

% end lyxskak.sty