var PREFIX = "http://www.apronus.com/images/chess/";
//var PREFIX = "chess_images/";
var EMPTY = 0;
var WHITEKING = 1;
var BLACKKING = 2;
var WHITEQUEEN = 3;
var BLACKQUEEN = 4;
var WHITEROOK = 5;
var BLACKROOK = 6;
var WHITEBISHOP = 7;
var BLACKBISHOP = 8;
var WHITEKNIGHT = 9;
var BLACKKNIGHT = 10;
var WHITEPAWN = 11;
var BLACKPAWN = 12;


var lightsquare = new Image();
var darksquare = new Image();

var whitekingonlight = new Image();
var whitequeenonlight = new Image();
var whiterookonlight = new Image();
var whitebishoponlight = new Image();
var whiteknightonlight = new Image();
var whitepawnonlight = new Image();
var whitekingondark = new Image();
var whitequeenondark = new Image();
var whiterookondark = new Image();
var whitebishopondark = new Image();
var whiteknightondark = new Image();
var whitepawnondark = new Image();

var blackkingondark = new Image();
var blackqueenondark = new Image();
var blackrookondark = new Image();
var blackbishopondark = new Image();
var blackknightondark = new Image();
var blackpawnondark = new Image();
var blackkingonlight = new Image();
var blackqueenonlight = new Image();
var blackrookonlight = new Image();
var blackbishoponlight = new Image();
var blackknightonlight = new Image();
var blackpawnonlight = new Image();

var emptysquareselected = new Image();
var whitekingselected = new Image();
var whitequeenselected = new Image();
var whiterookselected = new Image();
var whitebishopselected = new Image();
var whiteknightselected = new Image();
var whitepawnselected = new Image();
var blackkingselected = new Image();
var blackqueenselected = new Image();
var blackrookselected = new Image();
var blackbishopselected = new Image();
var blackknightselected = new Image();
var blackpawnselected = new Image();

function load_images(pathprefix)
{
 lightsquare.src = pathprefix + "lightsquare.gif";
 darksquare.src = pathprefix + "darksquare.gif";

 whitekingonlight.src = pathprefix + "whitekingonlight.gif";
 whitequeenonlight.src = pathprefix + "whitequeenonlight.gif";
 whiterookonlight.src = pathprefix + "whiterookonlight.gif";
 whitebishoponlight.src = pathprefix + "whitebishoponlight.gif";
 whiteknightonlight.src = pathprefix + "whiteknightonlight.gif";
 whitepawnonlight.src = pathprefix + "whitepawnonlight.gif";
 whitekingondark.src = pathprefix + "whitekingondark.gif";
 whitequeenondark.src = pathprefix + "whitequeenondark.gif";
 whiterookondark.src = pathprefix + "whiterookondark.gif";
 whitebishopondark.src = pathprefix + "whitebishopondark.gif";
 whiteknightondark.src = pathprefix + "whiteknightondark.gif";
 whitepawnondark.src = pathprefix + "whitepawnondark.gif";

 blackkingondark.src = pathprefix + "blackkingondark.gif";
 blackqueenondark.src = pathprefix + "blackqueenondark.gif";
 blackrookondark.src = pathprefix + "blackrookondark.gif";
 blackbishopondark.src = pathprefix + "blackbishopondark.gif";
 blackknightondark.src = pathprefix + "blackknightondark.gif";
 blackpawnondark.src = pathprefix + "blackpawnondark.gif";
 blackkingonlight.src = pathprefix + "blackkingonlight.gif";
 blackqueenonlight.src = pathprefix + "blackqueenonlight.gif";
 blackrookonlight.src = pathprefix + "blackrookonlight.gif";
 blackbishoponlight.src = pathprefix + "blackbishoponlight.gif";
 blackknightonlight.src = pathprefix + "blackknightonlight.gif";
 blackpawnonlight.src = pathprefix + "blackpawnonlight.gif";

 emptysquareselected.src = pathprefix + "emptysquareselected.gif";
 whitekingselected.src = pathprefix + "whitekingselected.gif";
 whitequeenselected.src = pathprefix + "whitequeenselected.gif";
 whiterookselected.src = pathprefix + "whiterookselected.gif";
 whitebishopselected.src = pathprefix + "whitebishopselected.gif";
 whiteknightselected.src = pathprefix + "whiteknightselected.gif";
 whitepawnselected.src = pathprefix + "whitepawnselected.gif";
 blackkingselected.src = pathprefix + "blackkingselected.gif";
 blackqueenselected.src = pathprefix + "blackqueenselected.gif";
 blackrookselected.src = pathprefix + "blackrookselected.gif";
 blackbishopselected.src = pathprefix + "blackbishopselected.gif";
 blackknightselected.src = pathprefix + "blackknightselected.gif";
 blackpawnselected.src = pathprefix + "blackpawnselected.gif";
}

load_images(PREFIX);

function squareIndex(width,height,x,y) { return (y-1)*width + x; }
function squareX(width,height,sqindex) { return (sqindex-1) % width + 1; }
function squareY(width,height,sqindex) { return Math.floor((sqindex-1) / width) + 1; }
function absoluteX(width,x,leftrightswitch) { if (leftrightswitch) return width-x+1; else return x; }
function absoluteY(height,y,updownswitch) { if (updownswitch) return height-y+1; else return y; }


function squarecolor(width,height,a1color,sqindex)
{
 var x = squareX(width,height,sqindex);
 var y = squareY(width,height,sqindex);
 if ((x+y)%2 == 0) return a1color;
 if (a1color == 'dark') return 'light';
 return 'dark';
}

function selected_image_name(what)
{
 switch (what)
 {
  case EMPTY       : return 'emptysquareselected';
  case WHITEKING   : return 'whitekingselected';
  case BLACKKING   : return 'blackkingselected';
  case WHITEQUEEN  : return 'whitequeenselected';
  case BLACKQUEEN  : return 'blackqueenselected';
  case WHITEROOK   : return 'whiterookselected';
  case BLACKROOK   : return 'blackrookselected';
  case WHITEBISHOP : return 'whitebishopselected';
  case BLACKBISHOP : return 'blackbishopselected';
  case WHITEKNIGHT : return 'whiteknightselected';
  case BLACKKNIGHT : return 'blackknightselected';
  case WHITEPAWN   : return 'whitepawnselected';
  case BLACKPAWN   : return 'blackpawnselected';
 }
 document.write("Error in selected_image_name()");
 return "";
}

function nonselected_image_name(width,height,a1color,sqindex,what)
{
 var color = squarecolor(width,height,a1color,sqindex);
 if (what == EMPTY) return color + 'square';
 switch(what)
 {
  case WHITEKING   : return 'whitekingon' + color;
  case BLACKKING   : return 'blackkingon' + color;
  case WHITEQUEEN  : return 'whitequeenon' + color;
  case BLACKQUEEN  : return 'blackqueenon' +  color;
  case WHITEROOK   : return 'whiterookon' + color;
  case BLACKROOK   : return 'blackrookon' +  color;
  case WHITEBISHOP : return 'whitebishopon' + color;
  case BLACKBISHOP : return 'blackbishopon' + color;
  case WHITEKNIGHT : return 'whiteknighton' + color;
  case BLACKKNIGHT : return 'blackknighton' + color;
  case WHITEPAWN   : return 'whitepawnon' + color;
  case BLACKPAWN   : return 'blackpawnon' + color;
 }
 document.write("error in loaded_image_name()");
 return "";
}

function setsquare(name,width,height,a1color,sqindex,what,selected)
{
 var img;
 if (selected)
 {
  img = selected_image_name(what);
 }
 else
 {
  img = nonselected_image_name(width,height,a1color,sqindex,what);
 }
 if (document.images[squarename(name,sqindex)].src != eval(img + ".src"))
 {
  document.images[squarename(name,sqindex)].src = eval(img + ".src");
 }
}

function setrelativesquare(name,width,height,a1color,sqindex,what,selected,leftrightswitch,updownswitch)
{
 var x = absoluteX(width,squareX(width,height,sqindex),leftrightswitch);
 var y = absoluteY(height,squareY(width,height,sqindex),updownswitch);
 sqindex = squareIndex(width,height,x,y);
 setsquare(name,width,height,a1color,sqindex,what,selected);
}


function refresh_deska(name,deska,width,height,a1color,leftrightswitch,updownswitch)
{
 var x,y,what;
 for (x=1; x<=width; x++) for (y=1; y<=height; y++)
 {
  what = deska[absoluteX(width,x,leftrightswitch)][absoluteY(height,y,updownswitch)];
  setsquare(name,width,height,a1color,squareIndex(width,height,x,y),what,false);
 }
}

function emptydeska(width,height)
{
 var deska = new Array();
 var x,y;
 for (x=1; x<=width; x++)
 {
  deska[x] = new Array();
  for (y=1; y<=height; y++)
  {
   deska[x][y] = EMPTY;
  }
 }
 return deska;
}

function startingdeska(width,height)
{
 var deska = emptydeska(width,height);
 if (height < 4)
 {
  alert("Starting position not available for current board dimensions.\nBoard height must be at least 4.");
  return;
 }
 if (width < 8)
 {
  alert("Starting position not available for current board dimensions.\nBoard width must be at least 8.");
  return;
 }

 var ilerazy = Math.floor(width/8);
 var i;
 for (i=0; i<ilerazy; i++)
 {
  deska[i*8+1][1] = WHITEROOK;
  deska[i*8+2][1] = WHITEKNIGHT;
  deska[i*8+3][1] = WHITEBISHOP;
  deska[i*8+4][1] = WHITEQUEEN;
  deska[i*8+5][1] = WHITEKING;
  deska[i*8+6][1] = WHITEBISHOP;
  deska[i*8+7][1] = WHITEKNIGHT;
  deska[i*8+8][1] = WHITEROOK;
  deska[i*8+1][2] = WHITEPAWN;
  deska[i*8+2][2] = WHITEPAWN;
  deska[i*8+3][2] = WHITEPAWN;
  deska[i*8+4][2] = WHITEPAWN;
  deska[i*8+5][2] = WHITEPAWN;
  deska[i*8+6][2] = WHITEPAWN;
  deska[i*8+7][2] = WHITEPAWN;
  deska[i*8+8][2] = WHITEPAWN;
  deska[i*8+1][height] = BLACKROOK;
  deska[i*8+2][height] = BLACKKNIGHT;
  deska[i*8+3][height] = BLACKBISHOP;
  deska[i*8+4][height] = BLACKQUEEN;
  deska[i*8+5][height] = BLACKKING;
  deska[i*8+6][height] = BLACKBISHOP;
  deska[i*8+7][height] = BLACKKNIGHT;
  deska[i*8+8][height] = BLACKROOK;
  deska[i*8+1][height-1] = BLACKPAWN;
  deska[i*8+2][height-1] = BLACKPAWN;
  deska[i*8+3][height-1] = BLACKPAWN;
  deska[i*8+4][height-1] = BLACKPAWN;
  deska[i*8+5][height-1] = BLACKPAWN;
  deska[i*8+6][height-1] = BLACKPAWN;
  deska[i*8+7][height-1] = BLACKPAWN;
  deska[i*8+8][height-1] = BLACKPAWN;
 }
 return deska;
}


// ========================================================================

function makemove(name,ruch,halfmove_number,deska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file)
{
 addruch(name,halfmove_number,ruch);

 var width = getwidth(name);
 var height = getheight(name);
 var pozycja = makepozycja(width,height,deska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
 addinternalpozycja(name,halfmove_number,pozycja);
}

function square_click(name,sqindex)
{
 var width = getwidth(name);
 var height = getheight(name);
 var a1color = geta1color(name);
 var whostarts = getwhostarts(name);

 var focussquare = getinternalfocussquare(name);
 var halfmove_number = gethalfmovenumber(name);
 var deska = deskaporuchu(name,halfmove_number);

 var whiteOO = whiteOOporuchu(name,halfmove_number);
 var whiteOOO = whiteOOOporuchu(name,halfmove_number);
 var blackOO = blackOOporuchu(name,halfmove_number);
 var blackOOO = blackOOOporuchu(name,halfmove_number);
 var enpassant_file = enpassantporuchu(name,halfmove_number);

 var leftrightswitch, updownswitch;
 if (isflipped(name))
 {
  leftrightswitch = true;
  updownswitch = true;
 }
 else
 {
  leftrightswitch = false;
  updownswitch = false;
 }

 var xx = absoluteX(width,squareX(width,height,sqindex),leftrightswitch);
 var yy = absoluteY(height,squareY(width,height,sqindex),updownswitch);
 var what = deska[xx][yy];
 var ruch;

 if (sqindex > width*height)
 {
  document.write("ERROR in square_click: (sqindex > width*height)");
  return;
 }

 if (focussquare == 0)
 {
  if (halfmove_number%2 == 0) // whostarts to play
  {
   if (whostarts == "White" || whostarts == "white")
   {
    zzz = white1square(deska,width,height,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
   }
   else
   {
    zzz = black1square(deska,width,height,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
   }
  }
  else
  {
   if (whostarts == "White" || whostarts == "white")
   {
    zzz = black1square(deska,width,height,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
   }
   else
   {
    zzz = white1square(deska,width,height,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
   }
  }
  if (zzz[0] == false)
  {
   if (zzz[1] == "possible")
   {
    setsquare(name,width,height,a1color,sqindex,what,true);
    sqindex = squareIndex(width,height,xx,yy);
    setinternalfocussquare(name,sqindex);
   }
   return;
  }
  ruch = zzz[1];
  deska = zzz[2]; // nowadeska
  whiteOO = zzz[3];
  whiteOOO = zzz[4];
  blackOO = zzz[5];
  blackOOO = zzz[6];
  enpassant_file = zzz[7];

  makemove(name,ruch,halfmove_number+1,deska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
  refresh_deska(name,deska,width,height,a1color,leftrightswitch,updownswitch);
  setinternalfocussquare(name,0);
  return;
 }

 var ax = squareX(width,height,focussquare);
 var ay = squareY(width,height,focussquare);

 if (ax == xx && ay == yy) // clicked the same square as was selected
 {
  setinternalfocussquare(name,0);
  what = deska[ax][ay];
  setrelativesquare(name,width,height,a1color,squareIndex(width,height,ax,ay),what,false,leftrightswitch,updownswitch);
  return;
 }

 if (halfmove_number%2 == 0) // whostarts to play
 {
  if (whostarts == "White" || whostarts == "white")
  {
   zzz = white2squares(deska,width,height,ax,ay,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
  }
  else
  {
   zzz = black2squares(deska,width,height,ax,ay,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
  }
 }
 else
 {
  if (whostarts == "White" || whostarts == "white")
  {
   zzz = black2squares(deska,width,height,ax,ay,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
  }
  else
  {
   zzz = white2squares(deska,width,height,ax,ay,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
  }
 }

 if (zzz[0] == false)
 {
  setinternalfocussquare(name,0);
  what = deska[ax][ay];
  setrelativesquare(name,width,height,a1color,squareIndex(width,height,ax,ay),what,false,leftrightswitch,updownswitch);
  square_click(name,sqindex);
  return;
 }

 ruch = zzz[1];
 deska = zzz[2]; // nowadeska
 whiteOO = zzz[3];
 whiteOOO = zzz[4];
 blackOO = zzz[5];
 blackOOO = zzz[6];
 enpassant_file = zzz[7];

 makemove(name,ruch,halfmove_number+1,deska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
 refresh_deska(name,deska,width,height,a1color,leftrightswitch,updownswitch);
 setinternalfocussquare(name,0);
}

// ========================================================================


// --- pozycja object --- 

function castling_char(whiteOO,whiteOOO,blackOO,blackOOO)
{
 var a = 0;
 if (whiteOO) a += 1;
 if (whiteOOO) a += 2;
 if (blackOO) a += 4;
 if (blackOOO) a += 8;
 return String.fromCharCode(a+64);
}

function char2whiteOO(znak)
{
 var aaa = "" + znak;
 var roszady = aaa.charCodeAt(0);
 return (roszady-64)%2 == 1;
}

function char2whiteOOO(znak)
{
 var aaa = "" + znak;
 var roszady = aaa.charCodeAt(0);
 return Math.floor((roszady-64)/2)%2 == 1;
}

function char2blackOO(znak)
{
 var aaa = "" + znak;
 var roszady = aaa.charCodeAt(0);
 return Math.floor((roszady-64)/4)%2 == 1;
}

function char2blackOOO(znak)
{
 var aaa = "" + znak;
 var roszady = aaa.charCodeAt(0);
 return Math.floor((roszady-64)/8)%2 == 1;
}

function getwhiteOO (pozycja) { return char2whiteOO (pozycja.charAt(0)); }
function getwhiteOOO(pozycja) { return char2whiteOOO(pozycja.charAt(0)); }
function getblackOO (pozycja) { return char2blackOO (pozycja.charAt(0)); }
function getblackOOO(pozycja) { return char2blackOOO(pozycja.charAt(0)); }
function getenpassant(width,height,pozycja) { return parseInt(pozycja.substring(width*height+1)); }

function pozycja2deska(width,height,pozycja)
{
 return deskuj(width,height,pozycja.substring(0,width*height+1));
}

function pozforchesswizard(width,height,pozycja)
{
 return "?" + pozycja.substring(1,width*height+1);
}

function makepozycja(width,height,deska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file)
{
 var pozycja = "";
 pozycja += castling_char(whiteOO,whiteOOO,blackOO,blackOOO);
 for (var i=1; i<=width*height; i++)
 {
  pozycja += what2znak(deska[squareX(width,height,i)][squareY(width,height,i)]);
 }
 pozycja += enpassant_file;
 return pozycja;
}

function znak2what(znak)
{
 switch (znak)
 {
  case '_' : return EMPTY;
  case 'K' : return WHITEKING;
  case 'k' : return BLACKKING;
  case 'Q' : return WHITEQUEEN;
  case 'q' : return BLACKQUEEN;
  case 'R' : return WHITEROOK;
  case 'r' : return BLACKROOK;
  case 'B' : return WHITEBISHOP;
  case 'b' : return BLACKBISHOP;
  case 'N' : return WHITEKNIGHT;
  case 'n' : return BLACKKNIGHT;
  case 'P' : return WHITEPAWN;
  case 'p' : return BLACKPAWN;
 }
 document.write("Error in function znak2what: " + znak + "<br/><br/>");
 return -1;
}

function startingpozycja(width,height)
{
 return makepozycja(width,height,startingdeska(width,height),true,true,true,true,0);
}

// --- end of pozycja object --- 


function squarename(name,sqindex) { return name + "_sq" + sqindex; }
function playboardformname(name) { return "playboard200608" + name; }
function diagramformname(name) { return "diagramform200609" + name; }

function html_clickboard(name,width,height)
{
 var x,y;
 var doc = "";
 doc += '<table border="1" cellspacing="0" cellpadding="0"><tr><td>\n';
 doc += ' <table border="0" cellspacing="0" cellpadding="0">\n';
 for (y=height; y>=1; y--)
 {
  doc += " <tr>\n";
  for (x=1; x<=width; x++)
  {
   doc += " <td><img width=\"36\" height=\"36\"\n";
   doc += ' name="';
   doc += squarename(name,squareIndex(width,height,x,y));
   doc += "\" onclick='square_click(\"";
   doc += name;
   doc += '",';
   doc += squareIndex(width,height,x,y);
   doc += ");' /></td>\n";
  }
  doc += " </tr>\n";
 }
 doc += " </table>\n";
 doc += "</td></tr></table>\n";
 return doc;
}

function html_playboard(name,width,height,pozycja,ruchy,whostarts,halfmove_number,flip)
{
 if (halfmove_number > (ruchy.split("_")).length)
 {
  document.write("ERROR in function html_playboard: halfmove_number > ruchy.length");
  return "";
 }
 var doc = "";

 doc += "<table border=\"0\" cellspacing=\"0\" cellpadding=\"0\">\n";
 doc += "<tr><td align=\"center\">\n";
 doc += html_clickboard(name,width,height);
 doc += "</td></tr><tr><td align=\"center\">\n";

 doc += "<form target=\"_blank\" method=\"post\"";
 doc += "\n action=\"http://www.apronus.com/chess/wizard.php\"";
 doc += "\nname=\"";
 doc += playboardformname(name);
 doc += "\">\n";

 doc += "<input type=\"hidden\" name=\"w\" value=\"";
 doc += width;
 doc += "\" />\n";

 doc += "<input type=\"hidden\" name=\"h\" value=\"";
 doc += height;
 doc += "\" />\n";

 doc += "<input type=\"hidden\" name=\"p\"\nvalue=\"";
 doc += pozycja;
 doc += "\"\n/>\n";

 doc += "<input type=\"hidden\" name=\"m\"\nvalue=\"";
 doc += ruchy;
 doc += "\"\n/>\n";

 doc += "<input type=\"hidden\" name=\"s\" value=\"";
 doc += whostarts;
 doc += "\" />\n";

 doc += "<input type=\"hidden\" name=\"n\" value=\"";
 doc += halfmove_number;
 doc += "\" />\n";

 doc += "<input type=\"hidden\" name=\"f\" value=\"";
 doc += flip;
 doc += "\" />\n";

 doc += "<div style=\"margin-top:0.5em;\">\n";

 doc += "<input style=\"width:3em;\" type=\"button\" value=\"&lt;&lt;\" onclick='firstday(\"";
 doc += name;
 doc += "\");' />\n";

 doc += "<input style=\"width:3em;\" type=\"button\" value=\"&lt;\" onclick='yesterday(\"";
 doc += name;
 doc += "\");' />\n";

 doc += "<input style=\"width:3em;\" type=\"button\" value=\"&gt;\" onclick='tomorrow(\"";
 doc += name;
 doc += "\");' />\n";

 doc += "<input style=\"width:3em;\" type=\"button\" value=\"&gt;&gt;\" onclick='lastday(\"";
 doc += name;
 doc += "\");' />\n";

 doc += "<input type=\"button\" value=\"Flip\" onclick='flipboard(\"";
 doc += name;
 doc += "\");' />\n";

 doc += "</div>\n";

 doc += "<div style=\"margin-top:0.5em;\">\n";
 doc += "<input type=\"submit\" value=\"Open in New Window\"/>\n";
 doc += "</div>\n";

 doc += "</form>\n";

 doc += "</td></tr></table>\n";

 return doc;
}

function getwidth(name) { return parseInt(eval("document.forms."+playboardformname(name)+".w.value")); }
function getheight(name) { return parseInt(eval("document.forms."+playboardformname(name)+".h.value")); }
function getzeropozycja(name) { return eval("document.forms."+playboardformname(name)+".p.value"); }

//function getruchy(name) { return eval("document.forms."+playboardformname(name)+".m.value"); }
//function setruchy(name,ruchy) { eval("document.forms."+playboardformname(name)+".m.value = \"" + ruchy + "\";"); }

function escapepluses(ruchy)
{
 if (ruchy == "") return "";
 return ruchy.split("+").join("*");
}
function regainpluses(kruchy)
{
 if (kruchy == "") return "";
 return kruchy.split("*").join("+");
}

function getruchy(name)
{
 var kruchy = eval("document.forms."+playboardformname(name)+".m.value");
 return regainpluses(kruchy);
}
function getruchyarray(name) { return getruchy(name).split("_"); }

function setruchy(name,ruchy)
{
 ruchy = escapepluses(ruchy);
 eval("document.forms."+playboardformname(name)+".m.value = \"" + ruchy + "\";");
}

function getwhostarts(name) { return eval("document.forms."+playboardformname(name)+".s.value"); }
function gethalfmovenumber(name) { return parseInt(eval("document.forms."+playboardformname(name)+".n.value")); }
function sethalfmovenumber(name,n) { eval("document.forms."+playboardformname(name)+".n.value = " + n + ";"); }

function addruch(name,halfmove_number,ruch)
{
 var ruchyarray = getruchy(name).split("_");
 var noweruchyarray = new Array(halfmove_number);
 var i;
 for (i=0; i<halfmove_number-1; i++)
 {
  noweruchyarray[i] = ruchyarray[i];
 }
 noweruchyarray[i] = ruch;
 sethalfmovenumber(name,halfmove_number);
 setruchy(name,noweruchyarray.join("_"));
}

function isflipped(name)
{
 var flip = eval("document.forms."+playboardformname(name)+".f.value");
 if (flip == "") return false;
 return true;
}

function swapflip(name)
{
 var flip =      eval("document.forms."+playboardformname(name)+".f.value");
 if (flip == "") eval("document.forms."+playboardformname(name)+".f.value = \"1\"");
 else            eval("document.forms."+playboardformname(name)+".f.value = \"\"");
}

function geta1color(name)
{
 var width = getwidth(name);
 var height = getheight(name);
 var a1color = "dark";
 if ((width%2 + height%2)%2 == 1 && isflipped(name)) a1color = "light";
 return a1color; 
}

function ileruchow(ruchy)
{
 if (ruchy == "") return 0;
 return ruchy.split("_").length;
}

function inicjuj_playboard(name,width,height,pozycja,ruchy,whostarts,halfmove_number,flip)
{
 if (pozycja == "") pozycja = startingpozycja(width,height);

 var ret = new Array(2);
 ret[0] = 0; //setinternalfocussquare(name,0);
 ret[1] = pozykwensuj(width,height,pozycja,ruchy,whostarts);

 if (halfmove_number<0) halfmove_number = ileruchow(ruchy);
 document.write(html_playboard(name,width,height,pozycja,ruchy,whostarts,halfmove_number,flip));

 var biezacapozycja = ret[1][halfmove_number];
 var deska = pozycja2deska(width,height,biezacapozycja);

 if (isflipped(name)) refresh_deska(name,deska,width,height,geta1color(name),true,true);
 else                 refresh_deska(name,deska,width,height,"dark",false,false);
 return ret;
}

function setinternalfocussquare(name,sqindex) { eval(name + "[0]=" + sqindex); }
function getinternalfocussquare(name) { return parseInt(eval(name + "[0]")); }

function addinternalpozycja(name,n,pozycja)
{
 if (isNaN(n) || n <= 0)
 {
  document.write("ERROR in function addinternalpozycja<br/><br/>");
  return;
 }
 var pozykwensarray = eval(name+"[1]");
 var novum = new Array(n+1);
 var i;
 for (i=0; i<n; i++)
 {
  novum[i] = pozykwensarray[i];
 }
 novum[n] = pozycja;
 eval(name+"[1]=novum;");
}

function pozycjaporuchu(name,n) { return eval(name+"[1]["+n+"]"); }
function deskaporuchu(name,n) { return pozycja2deska(getwidth(name),getheight(name),pozycjaporuchu(name,n)); }
function whiteOOporuchu(name,n) { return getwhiteOO(pozycjaporuchu(name,n)); }
function whiteOOOporuchu(name,n) { return getwhiteOOO(pozycjaporuchu(name,n)); }
function blackOOporuchu(name,n) { return getblackOO(pozycjaporuchu(name,n)); }
function blackOOOporuchu(name,n) { return getblackOOO(pozycjaporuchu(name,n)); }
function enpassantporuchu(name,n)
{ return getenpassant(getwidth(name),getheight(name),pozycjaporuchu(name,n)); }

function pozykwensuj(width,height,pozycja,ruchy,whostarts)
{
 var whiteOO = getwhiteOO(pozycja);
 var whiteOOO = getwhiteOOO(pozycja);
 var blackOO = getblackOO(pozycja);
 var blackOOO = getblackOOO(pozycja);
 var enpassant_file = getenpassant(width,height,pozycja);
 var i, z;
 var pozykwensarray = new Array();

 var halfmoves = ("?_"+ruchy).split("_");
 if (ruchy == "") halfmoves = new Array(1);
 halfmoves[0] = pozforchesswizard(width,height,pozycja);
 var lastdzien = halfmoves.length-1;
 for (i=0; i<=lastdzien; i++)
 {
  z = chesswizard(width,height,halfmoves,whostarts,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,i);
  // z = new Array(deska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
  pozykwensarray[i] = makepozycja(width,height,z[0],z[1],z[2],z[3],z[4],z[5]);
 }
 return pozykwensarray; 
}

function freshplayboard(name,width,height)
{
 return inicjuj_playboard(name,width,height,startingpozycja(width,height),"","White",0,"");
}


function firstday(name)
{
 var deska = deskaporuchu(name,0);
 var width = getwidth(name);
 var height = getheight(name);
 if (isflipped(name)) refresh_deska(name,deska,width,height,geta1color(name),true,true);
 else                 refresh_deska(name,deska,width,height,geta1color(name),false,false);

 sethalfmovenumber(name,0);
 setinternalfocussquare(name,0);
}

function lastday(name)
{
 var ruchy = getruchy(name);
 var lastdzien = ileruchow(ruchy);
 var deska = deskaporuchu(name,lastdzien);
 var width = getwidth(name);
 var height = getheight(name);
 if (isflipped(name)) refresh_deska(name,deska,width,height,geta1color(name),true,true);
 else                 refresh_deska(name,deska,width,height,geta1color(name),false,false);
 sethalfmovenumber(name,lastdzien);
 setinternalfocussquare(name,0);
}

function yesterday(name)
{
 var n = gethalfmovenumber(name);
 if (n > 0)
 {
  var deska = deskaporuchu(name,n-1);
  var width = getwidth(name);
  var height = getheight(name);
  if (isflipped(name)) refresh_deska(name,deska,width,height,geta1color(name),true,true);
  else                 refresh_deska(name,deska,width,height,geta1color(name),false,false);
  sethalfmovenumber(name,n-1);
 }
 setinternalfocussquare(name,0);
}

function tomorrow(name)
{
 var ruchy = getruchy(name);
 var lastdzien = (ruchy.split("_")).length;
 if (ruchy == "") lastdzien = 0;
 var n = gethalfmovenumber(name);
 if (n < lastdzien)
 {
  var deska = deskaporuchu(name,n+1);
  var width = getwidth(name);
  var height = getheight(name);
  if (isflipped(name)) refresh_deska(name,deska,width,height,geta1color(name),true,true);
  else                 refresh_deska(name,deska,width,height,geta1color(name),false,false);
  sethalfmovenumber(name,n+1);
 }
 setinternalfocussquare(name,0);
}

function flipboard(name)
{
 swapflip(name);
 var n = gethalfmovenumber(name);
 var deska = deskaporuchu(name,n);
 var width = getwidth(name);
 var height = getheight(name);

 if (isflipped(name)) refresh_deska(name,deska,width,height,geta1color(name),true,true);
 else                 refresh_deska(name,deska,width,height,geta1color(name),false,false);
 setinternalfocussquare(name,0);  
}

// ------------------ 


// --- chessknow

function literka(i)
{
 if (i==1) return "a";
 if (i==2) return "b";
 if (i==3) return "c";
 if (i==4) return "d";
 if (i==5) return "e";
 if (i==6) return "f";
 if (i==7) return "g";
 if (i==8) return "h";
 if (i==9) return "i";
 if (i==10) return "j";
 if (i==11) return "k";
 if (i==12) return "l";
 if (i==13) return "m";
 if (i==14) return "n";
 if (i==15) return "o";
 if (i==16) return "p";
 if (i==17) return "q";
 if (i==18) return "r";
 if (i==19) return "s";
 if (i==20) return "t";
 if (i==21) return "u";
 if (i==22) return "v";
 if (i==23) return "w";
 if (i==24) return "x";
 if (i==25) return "y";
 if (i==26) return "z";
 return "("+i+")";
}

function can_white(deska,width,height,ax,ay,bx,by)
{
 var x,y,i;
 var from = deska[ax][ay];
 var to = deska[bx][by];

 if (to == WHITEKING || to == WHITEQUEEN || to == WHITEROOK ||
     to == WHITEBISHOP || to == WHITEKNIGHT || to == WHITEPAWN) return false;

 if (from == WHITEKNIGHT)
 {
  x = (bx-ax);
  y = (by-ay);
  return x*y*x*y == 4; // :-)
 }

 if (from == WHITEKING)
 {
  x = (ax-bx);
  y = (ay-by);
  return x*x<=1 && y*y<=1;
 }

 if (from == WHITEPAWN)
 {
  if (ax == bx && ay+1 == by && deska[ax][by] == EMPTY) return true;
  if (height >= 7 && ax == bx && ay == 2 && by == 4 &&
      deska[ax][3] == EMPTY && deska[ax][4] == EMPTY) return true;
  return to!=EMPTY && ay+1 == by && (ax-1 == bx || ax+1 == bx);
 }

 if (from == WHITEROOK)
 {
  if (ax == bx && ay < by)
  {
   for (y=ay+1; y<by; y++) if (deska[ax][y] != EMPTY) return false;
   return true;
  }
  if (ax == bx && by < ay)
  {
   for (y=ay-1; y>by; y--) if (deska[ax][y] != EMPTY) return false;
   return true;
  }
  if (ay == by && ax < bx)
  {
   for (x=ax+1; x<bx; x++) if (deska[x][ay] != EMPTY) return false;
   return true;
  }
  if (ay == by && bx < ax)
  {
   for (x=ax-1; bx<x; x--) if (deska[x][ay] != EMPTY) return false;
   return true;
  }
  return false;  
 }

 if (from == WHITEBISHOP)
 {
  x = (bx-ax);
  y = (by-ay);
  if (x*x != y*y) return false;
  if (x>0 && y>0)
  {
   for (i=1; i<x; i++)
   {
    if (ax+i <= width && ay+i <= height && deska[ax+i][ay+i] != EMPTY) return false;
   }
   return true;
  }
  if (x>0 && y<0)
  {
   for (i=1; i<x; i++)
   {
    if (ax+i <= width && ay-i >= 1 && deska[ax+i][ay-i] != EMPTY) return false;
   }
   return true;
  }
  if (x<0 && y>0)
  {
   for (i=1; i<y; i++)
   {
    if (ax-i >=1 && ay+i <= height && deska[ax-i][ay+i] != EMPTY) return false;
   }
   return true;
  }
  if (x<0 && y<0)
  {
   for (i=1; i<-x; i++)
   {
    if (ax-i >= 1 && ay-i >= 1 && deska[ax-i][ay-i] != EMPTY) return false;
   }
   return true;
  }
  return false;
 }

 if (from == WHITEQUEEN)
 {
  if (ax == bx && ay < by)
  {
   for (y=ay+1; y<by; y++) if (deska[ax][y] != EMPTY) return false;
   return true;
  }
  if (ax == bx && by < ay)
  {
   for (y=ay-1; y>by; y--) if (deska[ax][y] != EMPTY) return false;
   return true;
  }
  if (ay == by && ax < bx)
  {
   for (x=ax+1; x<bx; x++) if (deska[x][ay] != EMPTY) return false;
   return true;
  }
  if (ay == by && bx < ax)
  {
   for (x=ax-1; bx<x; x--) if (deska[x][ay] != EMPTY) return false;
   return true;
  }
  x = (bx-ax);
  y = (by-ay);
  if (x*x != y*y) return false;
  if (x>0 && y>0)
  {
   for (i=1; i<x; i++)
   {
    if (ax+i <= width && ay+i <= height && deska[ax+i][ay+i] != EMPTY) return false;
   }
   return true;
  }
  if (x>0 && y<0)
  {
   for (i=1; i<x; i++)
   {
    if (ax+i <= width && ay-i >= 1 && deska[ax+i][ay-i] != EMPTY) return false;
   }
   return true;
  }
  if (x<0 && y>0)
  {
   for (i=1; i<y; i++)
   {
    if (ax-i >=1 && ay+i <= height && deska[ax-i][ay+i] != EMPTY) return false;
   }
   return true;
  }
  if (x<0 && y<0)
  {
   for (i=1; i<-x; i++)
   {
    if (ax-i >= 1 && ay-i >= 1 && deska[ax-i][ay-i] != EMPTY) return false;
   }
   return true;
  }
  return false;
 }

 return false;
}


function can_black(deska,width,height,ax,ay,bx,by)
{
 var x,y,i;
 var from = deska[ax][ay];
 var to = deska[bx][by];

 if (to == BLACKKING || to == BLACKQUEEN || to == BLACKROOK ||
     to == BLACKBISHOP || to == BLACKKNIGHT || to == BLACKPAWN) return false;

 if (from == BLACKKNIGHT)
 {
  x = (bx-ax);
  y = (by-ay);
  return x*y*x*y == 4; // :-)
 }

 if (from == BLACKKING)
 {
  x = (ax-bx);
  y = (ay-by);
  return x*x<=1 && y*y<=1;
 }

 if (from == BLACKPAWN)
 {
  if (ax == bx && ay == by+1 && deska[ax][by] == EMPTY) return true;
  if (height >= 7 && ax == bx && ay == height-1 && by == height-3 &&
       deska[ax][height-2] == EMPTY && deska[ax][height-3] == EMPTY) return true;
  return to!=EMPTY && ay-1 == by && (ax-1 == bx || ax+1 == bx);
 }

 if (from == BLACKROOK)
 {
  if (ax == bx && ay < by)
  {
   for (y=ay+1; y<by; y++) if (deska[ax][y] != EMPTY) return false;
   return true;
  }
  if (ax == bx && by < ay)
  {
   for (y=ay-1; y>by; y--) if (deska[ax][y] != EMPTY) return false;
   return true;
  }
  if (ay == by && ax < bx)
  {
   for (x=ax+1; x<bx; x++) if (deska[x][ay] != EMPTY) return false;
   return true;
  }
  if (ay == by && bx < ax)
  {
   for (x=ax-1; bx<x; x--) if (deska[x][ay] != EMPTY) return false;
   return true;
  }
  return false;  
 }

 if (from == BLACKBISHOP)
 {
  x = (bx-ax);
  y = (by-ay);
  if (x*x != y*y) return false;
  if (x>0 && y>0)
  {
   for (i=1; i<x; i++)
   {
    if (ax+i <= width && ay+i <= height && deska[ax+i][ay+i] != EMPTY) return false;
   }
   return true;
  }
  if (x>0 && y<0)
  {
   for (i=1; i<x; i++)
   {
    if (ax+i <= width && ay-i >= 1 && deska[ax+i][ay-i] != EMPTY) return false;
   }
   return true;
  }
  if (x<0 && y>0)
  {
   for (i=1; i<y; i++)
   {
    if (ax-i >=1 && ay+i <= height && deska[ax-i][ay+i] != EMPTY) return false;
   }
   return true;
  }
  if (x<0 && y<0)
  {
   for (i=1; i<-x; i++)
   {
    if (ax-i >= 1 && ay-i >= 1 && deska[ax-i][ay-i] != EMPTY) return false;
   }
   return true;
  }
  return false;
 }

 if (from == BLACKQUEEN)
 {
  if (ax == bx && ay < by)
  {
   for (y=ay+1; y<by; y++) if (deska[ax][y] != EMPTY) return false;
   return true;
  }
  if (ax == bx && by < ay)
  {
   for (y=ay-1; y>by; y--) if (deska[ax][y] != EMPTY) return false;
   return true;
  }
  if (ay == by && ax < bx)
  {
   for (x=ax+1; x<bx; x++) if (deska[x][ay] != EMPTY) return false;
   return true;
  }
  if (ay == by && bx < ax)
  {
   for (x=ax-1; bx<x; x--) if (deska[x][ay] != EMPTY) return false;
   return true;
  }
  x = (bx-ax);
  y = (by-ay);
  if (x*x != y*y) return false;
  if (x>0 && y>0)
  {
   for (i=1; i<x; i++)
   {
    if (ax+i <= width && ay+i <= height && deska[ax+i][ay+i] != EMPTY) return false;
   }
   return true;
  }
  if (x>0 && y<0)
  {
   for (i=1; i<x; i++)
   {
    if (ax+i <= width && ay-i >= 1 && deska[ax+i][ay-i] != EMPTY) return false;
   }
   return true;
  }
  if (x<0 && y>0)
  {
   for (i=1; i<y; i++)
   {
    if (ax-i >=1 && ay+i <= height && deska[ax-i][ay+i] != EMPTY) return false;
   }
   return true;
  }
  if (x<0 && y<0)
  {
   for (i=1; i<-x; i++)
   {
    if (ax-i >= 1 && ay-i >= 1 && deska[ax-i][ay-i] != EMPTY) return false;
   }
   return true;
  }
  return false;
 }

 return false;
}



function can_white_move(deska,width,height,ax,ay,bx,by)
{
 var x,y,kx,ky;
 var kings = 0;

 if (!can_white(deska,width,height,ax,ay,bx,by)) return false;

 //for (x=1; x<=width; x++) for (y=1; y<=height; y++)
 //{
  //if (deska[x][y] == WHITEKING)
  //{
   //kings++;
  //}
 //}
 //if (kings == 0 || kings > 1) return true;

 var imagina = new Array();
 for (x=1; x<=width; x++)
 {
  imagina[x] = new Array();
  for (y=1; y<=height; y++)
  {
   imagina[x][y] = deska[x][y];
  }
 }
 imagina[ax][ay] = EMPTY;
 imagina[bx][by] = deska[ax][ay];
 
 for (x=1; x<=width; x++) for (y=1; y<=height; y++)
 {
  if (imagina[x][y] == WHITEKING)
  {
   kx = x;
   ky = y;
  }
 }

 for (x=1; x<=width; x++) for (y=1; y<=height; y++)
 {
  if (can_black(imagina,width,height,x,y,kx,ky))
  {
   return false;
  }
 }
 return true;
}


function can_black_move(deska,width,height,ax,ay,bx,by)
{
 var x,y,kx,ky;
 var kings = 0;

 if (!can_black(deska,width,height,ax,ay,bx,by)) return false;

 //for (x=1; x<=width; x++) for (y=1; y<=height; y++)
 //{
  //if (deska[x][y] == BLACKKING)
  //{
   //kings++;
  //}
 //}
 //if (kings == 0 || kings > 1) return true;

 var imagina = new Array();
 for (x=1; x<=width; x++)
 {
  imagina[x] = new Array();
  for (y=1; y<=height; y++)
  {
   imagina[x][y] = deska[x][y];
  }
 }
 imagina[ax][ay] = EMPTY;
 imagina[bx][by] = deska[ax][ay];
 
 for (x=1; x<=width; x++) for (y=1; y<=height; y++)
 {
  if (imagina[x][y] == BLACKKING)
  {
   kx = x;
   ky = y;
  }
 }

 for (x=1; x<=width; x++) for (y=1; y<=height; y++)
 {
  if (can_white(imagina,width,height,x,y,kx,ky))
  {
   return false;
  }
 }
 return true;
}

function whiteincheck(deska,width,height)
{
 var x,y,kx,ky;
 var kings = 0;
 for (x=1; x<=width; x++) for (y=1; y<=height; y++)
 {
  if (deska[x][y] == WHITEKING)
  {
   kx = x;
   ky = y;
   kings++;
  }
 }
 if (kings == 0 || kings > 1) return "";
 for (x=1; x<=width; x++) for (y=1; y<=height; y++)
 {
  if (can_black(deska,width,height,x,y,kx,ky)) return "+";
 }
 return "";
}

function blackincheck(deska,width,height)
{
 var x,y,kx,ky;
 var kings = 0;
 for (x=1; x<=width; x++) for (y=1; y<=height; y++)
 {
  if (deska[x][y] == BLACKKING)
  {
   kx = x;
   ky = y;
   kings++;
  }
 }
 if (kings == 0 || kings > 1) return "";
 for (x=1; x<=width; x++) for (y=1; y<=height; y++)
 {
  if (can_white(deska,width,height,x,y,kx,ky)) return "+";
 }
 return "";
}


function inv63426sv35(inv,height,y)
{
 if (y == 0) return 0;
 if (inv == false) return y;
 return height-y+1;
}

function whitefromto(inv,deska,width,height,ax,ay,bx,by,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,promo)
{
 var from = deska[ax][ay];
 var to = deska[bx][by];
 var ruch;
 var x,y;
 var nowadeska = new Array();
 for (x=1; x<=width; x++)
 {
  nowadeska[x] = new Array()
  for (y=1; y<=height; y++)
  {
   nowadeska[x][y] = deska[x][y];
  }
 }

 // en passant
 if (from == WHITEPAWN && height >= 7 && ay == height-3 && by == height-2)
 {
  if (ax+1 == bx && deska[bx][by] == EMPTY && deska[bx][ay] == BLACKPAWN && enpassant_file == ax+1)
  {
   nowadeska[ax][ay] = EMPTY;
   nowadeska[bx][by] = WHITEPAWN;
   nowadeska[ax+1][ay] = EMPTY;
   ruch = literka(ax) + "x" + literka(bx) + inv63426sv35(inv,height,by) + blackincheck(nowadeska,width,height);
   return new Array(true,ruch,nowadeska,whiteOO,whiteOOO,blackOO,blackOOO,0);
  }
  if (ax-1 == bx && deska[bx][by] == EMPTY && deska[bx][ay] == BLACKPAWN && enpassant_file == ax-1)
  {
   nowadeska[ax][ay] = EMPTY;
   nowadeska[bx][by] = WHITEPAWN;
   nowadeska[ax-1][ay] = EMPTY;
   ruch = literka(ax) + "x" + literka(bx) + inv63426sv35(inv,height,by) + blackincheck(nowadeska,width,height);
   return new Array(true,ruch,nowadeska,whiteOO,whiteOOO,blackOO,blackOOO,0);
  }
 }

 if (whiteOO && from == WHITEKING && to == EMPTY && deska[6][1] == EMPTY && 
     deska[8][1] == WHITEROOK && ax == 5 && ay == 1 && by == 1 && bx == 7 && width == 8)
 {
  for (x=1; x<=width; x++) for (y=1; y<=height; y++)
  {
   if (can_black(deska,width,height,x,y,5,1))
   {
    ruch = "Illegal move: White cannot castle now because he is in check.";
    return new Array(false,ruch,nowadeska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
   }
  }
  for (x=1; x<=width; x++) for (y=1; y<=height; y++)
  {
   if (can_black(deska,width,height,x,y,7,1))
   {
    ruch = "Illegal move: White cannot castle short now because he would be in check afterwards.";
    return new Array(false,ruch,nowadeska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
   }
  }
  for (x=1; x<=width; x++) for (y=1; y<=height; y++)
  {
   if (can_black(deska,width,height,x,y,6,1))
   {
    ruch = "Illegal move: White cannot castle short now because f1 is attacked by Black.";
    return new Array(false,ruch,nowadeska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
   }
  }
  nowadeska[5][1] = EMPTY;
  nowadeska[6][1] = WHITEROOK;
  nowadeska[7][1] = WHITEKING;
  nowadeska[8][1] = EMPTY;
  ruch = "O-O" + blackincheck(nowadeska,width,height);
  return new Array(true,ruch,nowadeska,false,false,blackOO,blackOOO,0);
 }

 if (whiteOOO && from == WHITEKING && to == EMPTY && deska[2][1] == EMPTY && deska[3][1] == EMPTY &&
     deska[4][1] == EMPTY && deska[1][1] == WHITEROOK && ax == 5 && ay == 1 && bx == 3 && by == 1)
 {
  for (x=1; x<=width; x++) for (y=1; y<=height; y++)
  {
   if (can_black(deska,width,height,x,y,5,1))
   {
    ruch = "Illegal move: White cannot castle now because he is in check.";
    return new Array(false,ruch,nowadeska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
   }
  }
  for (x=1; x<=width; x++) for (y=1; y<=height; y++)
  {
   if (can_black(deska,width,height,x,y,3,1))
   {
    ruch = "Illegal move: White cannot castle long now because he would be in check afterwards.";
    return new Array(false,ruch,nowadeska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
   }
  }
  for (x=1; x<=width; x++) for (y=1; y<=height; y++)
  {
   if (can_black(deska,width,height,x,y,4,1))
   {
    ruch = "Illegal move: White cannot castle long now because d1 is attacked by Black.";
    return new Array(false,ruch,nowadeska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
   }
  }
  nowadeska[1][1] = EMPTY;
  nowadeska[3][1] = WHITEKING;
  nowadeska[4][1] = WHITEROOK;
  nowadeska[5][1] = EMPTY;
  ruch = "O-O-O" + blackincheck(nowadeska,width,height);
  return new Array(true,ruch,nowadeska,false,false,blackOO,blackOOO,0);
 }

 if (!can_white_move(deska,width,height,ax,ay,bx,by))
 {
  ruch = "Illegal move.";
  return new Array(false,ruch,nowadeska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
 }

 if (from == WHITEPAWN)
 {
  if (ax == bx && by != height)
  {
   nowadeska[ax][ay] = EMPTY;
   nowadeska[bx][by] = WHITEPAWN;
   ruch = literka(ax) + inv63426sv35(inv,height,by) + blackincheck(nowadeska,width,height);
   enpassant_file = 0;
   if (ay == 2 && by == 4) enpassant_file = ax;
   return new Array(true,ruch,nowadeska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
  }
  if (ax == bx && by == height)
  {
   var p = "(?)";
        if (promo == WHITEQUEEN)  p = "Q";
   else if (promo == WHITEROOK)   p = "R";
   else if (promo == WHITEBISHOP) p = "B";
   else if (promo == WHITEKNIGHT) p = "N";
   else promo = WHITEPAWN; // just in case of a vicious bug somewhere
   nowadeska[ax][ay] = EMPTY;
   nowadeska[bx][by] = promo;
   if (promo == WHITEPAWN)
   {
    ruch = "promotion";
   }
   else
   {
    ruch = literka(ax) + inv63426sv35(inv,height,by) + p + blackincheck(nowadeska,width,height);
   }
   return new Array(true,ruch,nowadeska,whiteOO,whiteOOO,blackOO,blackOOO,0);
  }
  if (by != height)
  {
   nowadeska[ax][ay] = EMPTY;
   nowadeska[bx][by] = WHITEPAWN;
   ruch = literka(ax) + "x" + literka(bx) + inv63426sv35(inv,height,by) + blackincheck(nowadeska,width,height);
   if (by == 8) blackOO = false;
   if (by == 1) blackOOO = false;
   return new Array(true,ruch,nowadeska,whiteOO,whiteOOO,blackOO,blackOOO,0);
  }
  var p = "(?)";
       if (promo == WHITEQUEEN)  p = "Q";
  else if (promo == WHITEROOK)   p = "R";
  else if (promo == WHITEBISHOP) p = "B";
  else if (promo == WHITEKNIGHT) p = "N";
  else promo = WHITEPAWN; // just in case of a vicious bug somewhere
  nowadeska[ax][ay] = EMPTY;
  nowadeska[bx][by] = promo;
  if (promo == WHITEPAWN)
  {
   ruch = "promotion";
  }
  else
  {
   ruch = literka(ax) + "x" + literka(bx) + inv63426sv35(inv,height,by) + p + blackincheck(nowadeska,width,height);
  }
  if (by == 8) blackOO = false;
  if (by == 1) blackOOO = false;
  return new Array(true,ruch,nowadeska,whiteOO,whiteOOO,blackOO,blackOOO,0);
 }

 var piece = "?";
 if (from == WHITEKING) piece = "K";
 if (from == WHITEQUEEN) piece = "Q";
 if (from == WHITEROOK) piece = "R";
 if (from == WHITEBISHOP) piece = "B";
 if (from == WHITEKNIGHT) piece = "N";

 var disambiguation = false;
 var letter = false;
 var digit = false;
 for (x=1; x<=width; x++) for (y=1; y<=height; y++)
 {
  if ((ax != x || ay != y) && deska[x][y] == from)
  {
   if (can_white_move(deska,width,height,x,y,bx,by))
   {
    disambiguation = true;
    if (ax == x) digit = true;
    if (ay == y) letter = true;
   }
  }
 }

      if (letter && digit) piece += literka(ax) + ay;
 else if (letter && !digit) piece += literka(ax);
 else if (!letter && digit) piece += ay;
 else if (disambiguation) piece += literka(ax);

 if (to != EMPTY) piece += "x";

 nowadeska[ax][ay] = EMPTY;
 nowadeska[bx][by] = from;
 ruch = piece + literka(bx) + inv63426sv35(inv,height,by) + blackincheck(nowadeska,width,height);

 if (from == WHITEKING)
 {
  whiteOO = false;
  whiteOOO = false;
 }
 if (ax == 1 && ay == 1)
 {
  whiteOOO = false;
 }
 if (ax == 8 && ay == 1)
 {
  whiteOO = false;
 }
 if (bx == 1 && by == height)
 {
  blackOOO = false;
 }
 if (bx == 8 && by == height)
 {
  blackOO = false;
 }
 
 return new Array(true,ruch,nowadeska,whiteOO,whiteOOO,blackOO,blackOOO,0);
}


function white2squares(deska,width,height,x1,y1,x2,y2,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file)
{
 var promo = EMPTY;
 var zzz = whitefromto(false,deska,width,height,x1,y1,x2,y2,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,promo);
 if (zzz[0])
 {
  if (zzz[1] == "promotion")
  {
   if (confirm("Do you want a Queen?\nClick Cancel for another piece."))
   {
    zzz = whitefromto(false,deska,width,height,x1,y1,x2,y2,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEQUEEN);
    return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x1,y1,x2,y2);
   }
   if (confirm("Do you want a Knight?"))
   {
    zzz = whitefromto(false,deska,width,height,x1,y1,x2,y2,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEKNIGHT);
    return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x1,y1,x2,y2);
   }
   if (confirm("Do you want a Rook?"))
   {
    zzz = whitefromto(false,deska,width,height,x1,y1,x2,y2,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEROOK);
    return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x1,y1,x2,y2);
   }
   zzz = whitefromto(false,deska,width,height,x1,y1,x2,y2,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEBISHOP);
   return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x1,y1,x2,y2);
  }
  return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x1,y1,x2,y2);
 }
 zzz = whitefromto(false,deska,width,height,x2,y2,x1,y1,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,promo);
 if (zzz[0])
 {
  if (zzz[1] == "promotion")
  {
   if (confirm("Do you want a Queen?\nClick Cancel for another piece."))
   {
    zzz = whitefromto(false,deska,width,height,x2,y2,x1,y1,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEQUEEN);
    return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x1,y1,x2,y2);
   }
   if (confirm("Do you want a Knight?"))
   {
    zzz = whitefromto(false,deska,width,height,x2,y2,x1,y1,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEKNIGHT);
    return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x1,y1,x2,y2);
   }
   if (confirm("Do you want a Rook?"))
   {
    zzz = whitefromto(false,deska,width,height,x2,y2,x1,y1,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEROOK);
    return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x1,y1,x2,y2);
   }
   zzz = whitefromto(false,deska,width,height,x2,y2,x1,y1,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEBISHOP);
   return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x1,y1,x2,y2);
  }
  return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x2,y2,x1,y1);
 }
 return new Array(false,zzz[1],deska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,0,0,0,0);
}

function white1square(deska,width,height,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file)
{
 var x,y,zzx,zzy;
 var zzz;
 var promo = EMPTY;

 var possible = false;
 var ile = 0;

 for (x=1; x<=width; x++) for (y=1; y<=height; y++)
 {
  zzz = whitefromto(false,deska,width,height,x,y,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,promo);
  if (zzz[0]) // possible legal move detected
  {
   possible = true;
   ile++;
   zzx = x;
   zzy = y;
  }
 }
 if (ile == 1)
 {
  zzz = whitefromto(false,deska,width,height,zzx,zzy,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,promo);
  if (zzz[1] != "promotion") return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],zzx,zzy,xx,yy);

  if (confirm("Do you want a Queen?\nClick Cancel for another piece."))
  {
   zzz = whitefromto(false,deska,width,height,zzx,zzy,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEQUEEN);
   return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],zzx,zzy,xx,yy);
  }
  if (confirm("Do you want a Knight?"))
  {
   zzz = whitefromto(false,deska,width,height,zzx,zzy,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEKNIGHT);
   return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],zzx,zzy,xx,yy);
  }
  if (confirm("Do you want a Rook?"))
  {
   zzz = whitefromto(false,deska,width,height,zzx,zzy,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEROOK);
   return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],zzx,zzy,xx,yy);
  }
  zzz = whitefromto(false,deska,width,height,zzx,zzy,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEBISHOP);
  return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],zzx,zzy,xx,yy);
 }

 ile = 0;
 for (x=1; x<=width; x++) for (y=1; y<=height; y++)
 {
  zzz = whitefromto(false,deska,width,height,xx,yy,x,y,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,promo);
  if (zzz[0]) // possible legal move for White detected
  {
   possible = true;
   ile++;
   zzx = x;
   zzy = y;
  }
 }
 if (ile == 1)
 {
  zzz = whitefromto(false,deska,width,height,xx,yy,zzx,zzy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,promo);
  if (zzz[1] != "promotion") return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],xx,yy,zzx,zzy);

  if (confirm("Do you want a Queen?\nClick Cancel for another piece."))
  {
   zzz = whitefromto(false,deska,width,height,xx,yy,zzx,zzy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEQUEEN);
   return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],zzx,zzy,xx,yy);
  }
  if (confirm("Do you want a Knight?"))
  {
   zzz = whitefromto(false,deska,width,height,xx,yy,zzx,zzy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEKNIGHT);
   return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],zzx,zzy,xx,yy);
  }
  if (confirm("Do you want a Rook?"))
  {
   zzz = whitefromto(false,deska,width,height,xx,yy,zzx,zzy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEROOK);
   return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],zzx,zzy,xx,yy);
  }
  zzz = whitefromto(false,deska,width,height,xx,yy,zzx,zzy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEBISHOP);
  return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],zzx,zzy,xx,yy);
 }

 if (possible) return new Array(false,"possible",deska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,0,0,0,0);
 return new Array(false,"impossible",deska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,0,0,0,0);
}

function isDigit(znak)
{
 if (znak == '0') return true;
 if (znak == '1') return true;
 if (znak == '2') return true;
 if (znak == '3') return true;
 if (znak == '4') return true;
 if (znak == '5') return true;
 if (znak == '6') return true;
 if (znak == '7') return true;
 if (znak == '8') return true;
 if (znak == '9') return true;
 return false;
}

function digit2number(znak)
{
 if (znak == '0') return 0;
 if (znak == '1') return 1;
 if (znak == '2') return 2;
 if (znak == '3') return 3;
 if (znak == '4') return 4;
 if (znak == '5') return 5;
 if (znak == '6') return 6;
 if (znak == '7') return 7;
 if (znak == '8') return 8;
 if (znak == '9') return 9;
 alert("ERROR: function digit2number received a nondigit character as argument");
 return 0;
}

function isLetter(znak)
{
 if (znak == 'a') return true;
 if (znak == 'b') return true;
 if (znak == 'c') return true;
 if (znak == 'd') return true;
 if (znak == 'e') return true;
 if (znak == 'f') return true;
 if (znak == 'g') return true;
 if (znak == 'h') return true;
 if (znak == 'i') return true;
 if (znak == 'j') return true;
 if (znak == 'k') return true;
 if (znak == 'l') return true;
 if (znak == 'm') return true;
 if (znak == 'n') return true;
 if (znak == 'o') return true;
 if (znak == 'p') return true;
 if (znak == 'q') return true;
 if (znak == 'r') return true;
 if (znak == 's') return true;
 if (znak == 't') return true;
 if (znak == 'u') return true;
 if (znak == 'v') return true;
 if (znak == 'w') return true;
 if (znak == 'x') return true;
 if (znak == 'y') return true;
 if (znak == 'z') return true;
 return false;
}

function letter2number(znak)
{
 if (znak == 'a') return 1;
 if (znak == 'b') return 2;
 if (znak == 'c') return 3;
 if (znak == 'd') return 4;
 if (znak == 'e') return 5;
 if (znak == 'f') return 6;
 if (znak == 'g') return 7;
 if (znak == 'h') return 8;
 if (znak == 'i') return 9;
 if (znak == 'j') return 10;
 if (znak == 'k') return 11;
 if (znak == 'l') return 12;
 if (znak == 'm') return 13;
 if (znak == 'n') return 14;
 if (znak == 'o') return 15;
 if (znak == 'p') return 16;
 if (znak == 'q') return 17;
 if (znak == 'r') return 18;
 if (znak == 's') return 19;
 if (znak == 't') return 20;
 if (znak == 'u') return 21;
 if (znak == 'v') return 22;
 if (znak == 'w') return 23;
 if (znak == 'x') return 24;
 if (znak == 'y') return 25;
 if (znak == 'z') return 26;
 alert("ERROR: non lowercaseletter character passed to function letter2number");
 return 0;
}


function parsemove(ruch)
{
 var error,kto,fromX,fromY,toX,toY,capture,check,promo;

 var last = ruch.length-1;

 if (last < 1)
 {
  error = 10;
  return new Array(error,0,0,0,0,0,false,false,"");
 }

 if (ruch.charAt(last) == "+")
 {
  check = true;
  last--;
  if (last < 1)
  {
   error = 11;
   return new Array(error,0,0,0,0,0,false,false,"");
  }
 }
 else check = false;

 if (ruch.charAt(last) == 'Q')
 {
  promo = "Q";
  last--;
  if (last < 1)
  {
   error = 12;
   return new Array(error,0,0,0,0,0,false,false,"");
  }
 }
 else if (ruch.charAt(last) == 'R')
 {
  promo = "R";
  last--;
  if (last < 1)
  {
   error = 13;
   return new Array(error,0,0,0,0,0,false,false,"");
  }
 }
 else if (ruch.charAt(last) == 'B')
 {
  promo = "B";
  last--;
  if (last < 1)
  {
   error = 14;
   return new Array(error,0,0,0,0,0,false,false,"");
  }
 }
 else if (ruch.charAt(last) == 'N')
 {
  promo = "N";
  last--;
  if (last < 1)
  {
   error = 15;
   return new Array(error,0,0,0,0,0,false,false,"");
  }
 }
 else promo = "_";

 if(!isDigit(ruch.charAt(last)))
 {
  error = 20;
  return new Array(error,0,0,0,0,0,false,false,"");
 }

 if (isDigit(ruch.charAt(last-1))) // rank number higher than 9 (double digit number)
 {
  var high = digit2number(ruch.charAt(last-1));
  var low = digit2number(ruch.charAt(last));
  toY = 10*high + low;
  if (toY < 10)
  {
   error = 30;
   return new Array(error,0,0,0,0,0,false,false,"");
  }
  last--;
  last--;
  if (last < 0)
  {
   error = 40;
   return new Array(error,0,0,0,0,0,false,false,"");
  }
 }
 else // rank number lower than 10 (one digit number)
 {
  toY = digit2number(ruch.charAt(last));
  if (toY == 0)
  {
   error = 50;
   return new Array(error,0,0,0,0,0,false,false,"");
  }
  last--;
  if (last < 0)
  {
   error = 60;
   return new Array(error,0,0,0,0,0,false,false,"");
  } 
 }
 // at this point toY is successfully determined

 if (!isLetter(ruch.charAt(last)))
 {
  error = 70;
  return new Array(error,0,0,0,0,0,false,false,"");
 }

 toX = letter2number(ruch.charAt(last));

 last--;
 if (last < 0)
 {
  return new Array(0,"P",toX,0,toX,toY,false,check,promo);
 }

 // at this point toX and toY are successfully determined

 if (ruch.charAt(last) == 'x')
 {
  capture = true;
  last--;
  if (last < 0)
  {
   error = 75;
   return new Array(error,0,0,0,0,0,false,false,"");
  }
  if (last == 0 && isLetter(ruch.charAt(last)))
  {
   fromX = letter2number(ruch.charAt(last));
   return new Array(0,"P",fromX,0,toX,toY,true,check,promo);
  }
 }
 else capture = false;

 // at this point capture, toX, toY are successfully determined

 if (isDigit(ruch.charAt(last)))
 {
  if (last == 0)
  {
   error = 80;
   return new Array(error,0,0,0,0,0,false,false,"");
  }
  if (isDigit(ruch.charAt(last-1)))
  {
   var high = digit2number(ruch.charAt(last-1));
   var low = digit2number(ruch.charAt(last));
   fromY = 10*high+low;
   if (fromY < 10)
   {
    error = 90;
    return new Array(error,0,0,0,0,0,false,false,"");
   }
   last--;
   last--;
   if (last < 0)
   {
    error = 100;
    return new Array(error,0,0,0,0,0,false,false,"");
   }
  }
  else
  {
   fromY = digit2number(ruch.charAt(last));
   if (fromY == 0)
   {
    error = 110;
    return new Array(error,0,0,0,0,0,false,false,"");
   }
   last--;
   if (last < 0)
   {
    error = 120;
    return new Array(error,0,0,0,0,0,false,false,"");
   }
  }
 }
 else fromY = 0;

 // at this point fromY, capture, toX, toY are successfully determined

 if (isLetter(ruch.charAt(last)))
 {
  fromX = letter2number(ruch.charAt(last));
  last--;
  if (last < 0)
  {
   error = 130;
   return new Array(error,0,0,0,0,0,false,false,"");
  }
 }
 else fromX = 0;

 // at this point fromX, fromY, capture, toX, toY are successfully determined

 if (last > 0)
 {
  error = 140;
  return new Array(error,0,0,0,0,0,false,false,"");
 }

 if (ruch.charAt(last) == 'K') kto = "K";
 else if (ruch.charAt(last) == 'Q') kto = "Q";
 else if (ruch.charAt(last) == 'R') kto = "R";
 else if (ruch.charAt(last) == 'B') kto = "B";
 else if (ruch.charAt(last) == 'N') kto = "N";
 else
 {
  error = 150;
  return new Array(error,0,0,0,0,0,false,false,"");
 }

 return new Array(0,kto,fromX,fromY,toX,toY,capture,check,promo);
}


function whiteharmony(chessman,kto)
{
 if (chessman == WHITEKING && kto == 'K') return true;
 if (chessman == WHITEQUEEN && kto == 'Q') return true;
 if (chessman == WHITEROOK && kto == 'R') return true;
 if (chessman == WHITEBISHOP && kto == 'B') return true;
 if (chessman == WHITEKNIGHT && kto == 'N') return true;
 if (chessman == WHITEPAWN && kto == 'P') return true;
 return false;
}

function whitetomove(inv,deska,width,height,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,ruch)
{
 if (ruch.length > 4)
 {
  if (ruch.charAt(0) == 'O' && ruch.charAt(1) == '-' && ruch.charAt(2) == 'O' &&
      ruch.charAt(3) == '-' && ruch.charAt(4) == 'O')
  {
   return whitefromto(inv,deska,width,height,5,1,3,1,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
  }
 }
 if (ruch.length > 2)
 {
  if (ruch.charAt(0) == 'O' && ruch.charAt(1) == '-' && ruch.charAt(2) == 'O')
  {
   return whitefromto(inv,deska,width,height,5,1,7,1,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
  }
 }

 var error,kto,fromX,fromY,toX,toY,capture,check,promo;
 var kuba,ile;
 var zzz = parsemove(ruch);
 if (zzz[0] > 0) // error parsing "ruch"
 {
  return new Array(false,"",deska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
 }
 kto = zzz[1];
 fromX = zzz[2];
 fromY = inv63426sv35(inv,height,zzz[3]);
 toX = zzz[4];
 toY = inv63426sv35(inv,height,zzz[5]);
 //capture = zzz[6];
 //check = zzz[7];
 promo = znak2what(zzz[8]);

 ile = 0;
 var ax,bx;
 for(x=1; x<=width; x++) for (y=1; y<=height; y++)
 {
  kuba = whitefromto(inv,deska,width,height,x,y,toX,toY,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,promo);
  if (kuba[0])
  {
   if ((fromX == 0 || fromX == x) && (fromY == 0 || fromY == y) && whiteharmony(deska[x][y],kto))
   {
    ile++;
    ax = x;
    ay = y;
   }
  }
 }
 if (ile == 1)
 {
  return whitefromto(inv,deska,width,height,ax,ay,toX,toY,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,promo);
 }

 return new Array(false,"",deska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
}


function switchcolor(x)
{
 if (x == EMPTY) return EMPTY;
 if (x == WHITEKING) return BLACKKING;
 if (x == WHITEQUEEN) return BLACKQUEEN;
 if (x == WHITEROOK) return BLACKROOK;
 if (x == WHITEBISHOP) return BLACKBISHOP;
 if (x == WHITEKNIGHT) return BLACKKNIGHT;
 if (x == WHITEPAWN) return BLACKPAWN;
 if (x == BLACKKING) return WHITEKING;
 if (x == BLACKQUEEN) return WHITEQUEEN;
 if (x == BLACKROOK) return WHITEROOK;
 if (x == BLACKBISHOP) return WHITEBISHOP;
 if (x == BLACKKNIGHT) return WHITEKNIGHT;
 if (x == BLACKPAWN) return WHITEPAWN;
 document.write("ERROR: function switchcolor received an illegal argument");
 return 0;
}

function invert(deska,width,height)
{
 var invertdeska = new Array();
 var x,y;
 for (x=1; x<=width; x++)
 {
  invertdeska[x] = new Array();
  for (y=1; y<=height; y++)
  {
   invertdeska[x][y] = switchcolor(deska[x][height-y+1]);
  }
 }
 return invertdeska;
}


function blackfromto(deska,width,height,ax,ay,bx,by,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,promo)
{
 var z = whitefromto(true,invert(deska,width,height),width,height,ax,height-ay+1,bx,height-by+1,
                       blackOO,blackOOO,whiteOO,whiteOOO,enpassant_file,promo);

 return new Array(z[0],z[1],invert(z[2],width,height),z[5],z[6],z[3],z[4],z[7]); 
}


function black2squares(deska,width,height,x1,y1,x2,y2,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file)
{
 var promo = EMPTY;
 var zzz = blackfromto(deska,width,height,x1,y1,x2,y2,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,promo);
 if (zzz[0])
 {
  if (zzz[1] == "promotion")
  {
   if (confirm("Do you want a Queen?\nClick Cancel for another piece."))
   {
    zzz = blackfromto(deska,width,height,x1,y1,x2,y2,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEQUEEN);
    return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x1,y1,x2,y2);
   }
   if (confirm("Do you want a Knight?"))
   {
    zzz = blackfromto(deska,width,height,x1,y1,x2,y2,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEKNIGHT);
    return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x1,y1,x2,y2);
   }
   if (confirm("Do you want a Rook?"))
   {
    zzz = blackfromto(deska,width,height,x1,y1,x2,y2,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEROOK);
    return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x1,y1,x2,y2);
   }
   zzz = blackfromto(deska,width,height,x1,y1,x2,y2,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEBISHOP);
   return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x1,y1,x2,y2);
  }
  return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x1,y1,x2,y2);
 }
 zzz = blackfromto(deska,width,height,x2,y2,x1,y1,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,promo);
 if (zzz[0])
 {
  if (zzz[1] == "promotion")
  {
   if (confirm("Do you want a Queen?\nClick Cancel for another piece."))
   {
    zzz = blackfromto(deska,width,height,x2,y2,x1,y1,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEQUEEN);
    return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x1,y1,x2,y2);
   }
   if (confirm("Do you want a Knight?"))
   {
    zzz = blackfromto(deska,width,height,x2,y2,x1,y1,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEKNIGHT);
    return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x1,y1,x2,y2);
   }
   if (confirm("Do you want a Rook?"))
   {
    zzz = blackfromto(deska,width,height,x2,y2,x1,y1,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEROOK);
    return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x1,y1,x2,y2);
   }
   zzz = blackfromto(deska,width,height,x2,y2,x1,y1,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEBISHOP);
   return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x1,y1,x2,y2);
  }
  return new Array(zzz[0],zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],x2,y2,x1,y1);
 }
 return new Array(false,zzz[1],deska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,0,0,0,0);
}

function black1square(deska,width,height,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file)
{
 var x,y,zzx,zzy;
 var zzz;
 var promo = EMPTY;

 var possible = false;
 var ile = 0;

 for (x=1; x<=width; x++) for (y=1; y<=height; y++)
 {
  zzz = blackfromto(deska,width,height,x,y,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,promo);
  if (zzz[0]) // possible legal move detected
  {
   possible = true;
   ile++;
   zzx = x;
   zzy = y;
  }
 }
 if (ile == 1)
 {
  zzz = blackfromto(deska,width,height,zzx,zzy,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,promo);
  if (zzz[1] != "promotion") return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],zzx,zzy,xx,yy);

  if (confirm("Do you want a Queen?\nClick Cancel for another piece."))
  {
   zzz = blackfromto(deska,width,height,zzx,zzy,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEQUEEN);
   return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],zzx,zzy,xx,yy);
  }
  if (confirm("Do you want a Knight?"))
  {
   zzz = blackfromto(deska,width,height,zzx,zzy,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEKNIGHT);
   return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],zzx,zzy,xx,yy);
  }
  if (confirm("Do you want a Rook?"))
  {
   zzz = blackfromto(deska,width,height,zzx,zzy,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEROOK);
   return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],zzx,zzy,xx,yy);
  }
  zzz = blackfromto(deska,width,height,zzx,zzy,xx,yy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEBISHOP);
  return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],zzx,zzy,xx,yy);
 }

 ile = 0;
 for (x=1; x<=width; x++) for (y=1; y<=height; y++)
 {
  zzz = blackfromto(deska,width,height,xx,yy,x,y,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,promo);
  if (zzz[0]) // possible legal move detected
  {
   possible = true;
   ile++;
   zzx = x;
   zzy = y;
  }
 }
 if (ile == 1)
 {
  zzz = blackfromto(deska,width,height,xx,yy,zzx,zzy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,promo);
  if (zzz[1] != "promotion") return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],xx,yy,zzx,zzy);

  if (confirm("Do you want a Queen?\nClick Cancel for another piece."))
  {
   zzz = blackfromto(deska,width,height,xx,yy,zzx,zzy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEQUEEN);
   return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],zzx,zzy,xx,yy);
  }
  if (confirm("Do you want a Knight?"))
  {
   zzz = blackfromto(deska,width,height,xx,yy,zzx,zzy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEKNIGHT);
   return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],zzx,zzy,xx,yy);
  }
  if (confirm("Do you want a Rook?"))
  {
   zzz = blackfromto(deska,width,height,xx,yy,zzx,zzy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEROOK);
   return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],zzx,zzy,xx,yy);
  }
  zzz = blackfromto(deska,width,height,xx,yy,zzx,zzy,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,WHITEBISHOP);
  return new Array(true,zzz[1],zzz[2],zzz[3],zzz[4],zzz[5],zzz[6],zzz[7],zzx,zzy,xx,yy);
 }

 if (possible) return new Array(false,"possible",deska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,0,0,0,0);
 return new Array(false,"impossible",deska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,0,0,0,0);
}


function blacktomove(deska,width,height,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,ruch)
{
 var z = whitetomove(true,invert(deska,width,height),width,height,
                     blackOO,blackOOO,whiteOO,whiteOOO,enpassant_file,ruch);
 return new Array(z[0],z[1],invert(z[2],width,height),z[5],z[6],z[3],z[4],z[7]);
}


function what2znak(what)
{
 switch (what)
 {
  case EMPTY       : return '_';
  case WHITEKING   : return 'K';
  case BLACKKING   : return 'k';
  case WHITEQUEEN  : return 'Q';
  case BLACKQUEEN  : return 'q';
  case WHITEROOK   : return 'R';
  case BLACKROOK   : return 'r';
  case WHITEBISHOP : return 'B';
  case BLACKBISHOP : return 'b';
  case WHITEKNIGHT : return 'N';
  case BLACKKNIGHT : return 'n';
  case WHITEPAWN   : return 'P';
  case BLACKPAWN   : return 'p';
 }
 document.write("Error in function what2znak");
 return '?'
}


function deskuj(width,height,poz)
{
 if (poz.length != width*height+1)
 {
  document.write("ERROR in function deskuj: poz.length != width*height+1");
  return new Array();
 }
 var deska = new Array();
 var x,y;
 for (x=1; x<=width; x++)
 {
  deska[x] = new Array();
  for (y=1; y<=height; y++)
  {
   deska[x][y] = znak2what(poz.charAt(squareIndex(width,height,x,y)));
  }
 }
 return deska;
}

function chesswizard(width,height,halfmoves,whostarts,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,halfmove_number)
{
 if (halfmove_number >= halfmoves.length)
 {
  document.write("ERROR in function chesswizard: halfmove_number >= halfmoves.length");
  return new Array();
 }

 var zeropoz = halfmoves[0]; // note the convention that zero position is stored like this
 var deska = deskuj(width,height,zeropoz);
 var i;
 var whoplays = whostarts;
 var ruch;
 var zzz;
 for (i=1; i<=halfmove_number; i++)
 {
  ruch = halfmoves[i];
  if (whoplays == "White" || whoplays == "white")
  {
   zzz = whitetomove(false,deska,width,height,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,ruch);
   if (zzz[0] == false)
   {
    document.write("ERROR in chesswizard: 10</br>i="+i+"</br></br>");
    document.write(halfmoves);
    return new Array(deska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
   }
   deska = zzz[2]; // nowadeska
   whiteOO = zzz[3];
   whiteOOO = zzz[4];
   blackOO = zzz[5];
   blackOOO = zzz[6];
   enpassant_file = zzz[7];
   whoplays = "Black";
  }
  else
  {
   zzz = blacktomove(deska,width,height,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file,ruch);
   if (zzz[0] == false)
   {
    document.write("ERROR in chesswizard: 20");
    return new Array(deska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
   }
   deska = zzz[2]; // nowadeska
   whiteOO = zzz[3];
   whiteOOO = zzz[4];
   blackOO = zzz[5];
   blackOOO = zzz[6];
   enpassant_file = zzz[7];
   whoplays = "White";
  }
 }
 return new Array(deska,whiteOO,whiteOOO,blackOO,blackOOO,enpassant_file);
}


// --- export

function exportURL(name,prefix)
{
 if (prefix == "") prefix = "http://www.apronus.com/chess/wizard.php";
 var width = getwidth(name);
 var height = getheight(name);
 var poza = getzeropozycja(name);
 var ruchy = escapepluses(getruchy(name));
 var whostarts = getwhostarts(name);
 var halfmove_number = gethalfmovenumber(name);
 var flip = isflipped(name);
 var url = prefix + "?";
 if (whostarts == "Black" || whostarts == "black") url += "s=black&";
 if (poza != startingpozycja(width,height)) url += "p="+poza+"&";
 if (ruchy != "") url += "m="+ruchy+"&";
 if (width != 8) url += "w="+width+"&";
 if (height != 8) url += "h="+height+"&";
 if (halfmove_number != ileruchow(ruchy)) url += "n="+halfmove_number+"&";
 if (flip) url += "f=1";

 if (url.charAt(url.length-1) == '&') return url.substring(0,url.length-1);
 return url;
}

function exportmoves1(name)
{
 var ruchy = getruchy(name);
 var ile = ileruchow(ruchy);
 if (ile == 0) return "";
 if (getwhostarts(name) == "black" || getwhostarts(name) == "Black")
 {
  ruchy = "..._"+ruchy;
  ile++;
 }
 ruchy = "?_"+ruchy;
 var zuege = ruchy.split("_");
 var i,doc="";
 for (i=1; i<=ile; i++)
 {
   if (i%2==1)
   {
    doc += ((i+1)/2) + ". " + zuege[i] + " ";
   }
    else
   {
    doc += zuege[i] + " ";
   }  
 }
 return doc;
}

function exportmoves2(name)
{
 var ruchy = getruchy(name);
 var ile = ileruchow(ruchy);
 if (ile == 0) return "";
 if (getwhostarts(name) == "black" || getwhostarts(name) == "Black")
 {
  ruchy = "..._"+ruchy;
  ile++;
 }
 ruchy = "?_"+ruchy;
 var zuege = ruchy.split("_");
 var i,doc="";
 for (i=1; i<=ile; i++)
 {
   if (i%2==1)
   {
    doc += ((i+1)/2) + ". " + zuege[i] + " ";
   }
    else
   {
    doc += zuege[i] + "\n";
   }  
 }
 return doc;
}

function exportmoves3(name)
{
 var ruchy = getruchy(name);
 var ile = ileruchow(ruchy);
 if (ile == 0) return "";
 if (getwhostarts(name) == "black" || getwhostarts(name) == "Black")
 {
  ruchy = "..._"+ruchy;
  ile++;
 }
 ruchy = "?_"+ruchy;
 var zuege = ruchy.split("_");
 var i,doc="";
 for (i=1; i<=ile; i++)
 {
   if (i%2==1)
   {
    doc += ((i+1)/2) + ". " + zuege[i] + " ";
   }
    else
   {
    doc += zuege[i] + "<br/>\n";
   }  
 }
 return doc;
}


function exportmoves4(name)
{
 var ruchy = getruchy(name);
 var ile = ileruchow(ruchy);
 if (ile == 0) return "";
 if (getwhostarts(name) == "black" || getwhostarts(name) == "Black")
 {
  ruchy = "..._"+ruchy;
  ile++;
 }
 ruchy = "?_"+ruchy;
 var zuege = ruchy.split("_");
 var i;
 var doc = "<table>\n";
 for (i=1; i<=ile; i++)
 {
   if (i%2==1)
   {
    doc += "<tr><td align=\"right\">" + ((i+1)/2) + ".&nbsp;</td><td>" + zuege[i] + "</td><td>&nbsp;</td>";
   }
    else
   {
    doc += "<td>"+zuege[i] + "</td></tr>\n";
   }  
 }
 if (ile%2==1)
 {
  doc += "<td>&nbsp;</td></tr>\n";
 }
 doc += "</table>\n";
 return doc;
}


function diagramsrc(name)
{
 var imgsrc = "";
 imgsrc += "http://www.apronus.com/chess/diagram-jpg.php?";
 imgsrc += "w=";
 imgsrc += getwidth("aaa");
 imgsrc += "&h=";
 imgsrc += getheight(name);
 imgsrc += "&d=";
 imgsrc += pozycjaporuchu(name,gethalfmovenumber(name));
 if (isflipped(name)) imgsrc += "&f=1";
 return imgsrc;
}

function makediagram(name)
{
 var doc = "document.forms."+diagramformname(name)+".d.value='"+pozycjaporuchu(name,gethalfmovenumber(name))+"';";
 eval(doc);
 if (isflipped(name))
 {
  eval("document.forms."+diagramformname(name)+".f.value=\"1\";");
 }
 else
 {
  eval("document.forms."+diagramformname(name)+".f.value=\"\";");
 }
 eval("document.forms."+diagramformname(name)+".submit();");
}

function html_makediagrambutton(name)
{
 var doc = "";
 doc += " <form name=\"";
 doc += diagramformname(name);
 doc += "\"\n       ";
 doc += "action=\"http://www.apronus.com/chess/diagram-jpg.php\"\n       ";
 doc += "target=\"_blank\" method=\"post\">\n   ";
 doc += "<input type=\"button\" value=\"Make Diagram\"";
 doc += " onclick=\"makediagram('"+name+"');\" />\n   ";
 doc += "<input type=\"hidden\" name=\"d\" />\n   ";
 doc += "<input type=\"hidden\" name=\"w\" value=\"";
 doc += width;
 doc += "\" />\n   ";
 doc += "<input type=\"hidden\" name=\"h\" value=\"";
 doc += height;
 doc += "\" />\n   ";
 doc += "<input type=\"hidden\" name=\"f\" value=\"";
 doc += flip;
 doc += "\" />\n";
 doc += " </form>\n";
 return doc;
}

function random_name()
{
 return "gdtwfetfd673tegeug74te67t76r251r";
}

function html_init(name)
{
 var randomname = random_name();
 var doc = "";
 doc += "<s";
 doc += "cript type=\"text/javascript\"";
 doc += " src=\"http://www.apronus.com/chess/wiseboard2006.js\"></s";
 doc += "cript>\n\n";
 doc += "<s";
 doc += "cript type=\"text/javascript\">\n";
 doc += "//<![CDATA[\n";
 doc += "var ";
 doc += randomname;
 doc += " = init_playboard(\n  \"";
 doc += randomname;
 doc += "\",\n  \"";
 doc += getzeropozycja(name);
 doc += "\",\n  \"";
 doc += getruchy(name);
 doc += "\",\n  \"";
 doc += getwhostarts(name);
 doc += "\",";
 doc += gethalfmovenumber(name);
 doc += ",";
 if (isflipped(name)) doc += "\"1\""; else doc += "\"\"";
 doc += ");\n";
 doc += "//]]>\n";
 doc += "</s";
 doc += "cript>\n";
 return doc;
}

function html_public_playboard(name,pozycja,ruchy,whostarts,halfmove_number,flip)
{
 var width = 8;
 var height = 8;
 if (halfmove_number > (ruchy.split("_")).length)
 {
  document.write("ERROR in function html_public_playboard: halfmove_number > ruchy.length");
  return "";
 }
 var doc = "";

 doc += "<table border=\"0\" cellspacing=\"0\" cellpadding=\"0\">\n";
 doc += "<tr><td align=\"center\">\n";
 doc += "<div style=\"margin-bottom:0.5em;\">\n"; 
 doc += "live diagram generated at ";
 doc += "<a href=\"http://www.apronus.com/\">";
 doc += "Apronus.com</a>\n";
 doc += "</div>\n";
 doc += "</td></tr><tr><td align=\"center\">\n";
 doc += html_clickboard(name,width,height);
 doc += "</td></tr><tr><td align=\"center\">\n";

 doc += "<form target=\"_blank\" method=\"post\"";
 doc += "\n action=\"http://www.apronus.com/chess/wizard.php\"";
 doc += "\nname=\"";
 doc += playboardformname(name);
 doc += "\">\n";

 doc += "<input type=\"hidden\" name=\"w\" value=\"";
 doc += width;
 doc += "\" />\n";

 doc += "<input type=\"hidden\" name=\"h\" value=\"";
 doc += height;
 doc += "\" />\n";

 doc += "<input type=\"hidden\" name=\"p\"\nvalue=\"";
 doc += pozycja;
 doc += "\"\n/>\n";

 doc += "<input type=\"hidden\" name=\"m\"\nvalue=\"";
 doc += ruchy;
 doc += "\"\n/>\n";

 doc += "<input type=\"hidden\" name=\"s\" value=\"";
 doc += whostarts;
 doc += "\" />\n";

 doc += "<input type=\"hidden\" name=\"n\" value=\"";
 doc += halfmove_number;
 doc += "\" />\n";

 doc += "<input type=\"hidden\" name=\"f\" value=\"";
 doc += flip;
 doc += "\" />\n";

 doc += "<div style=\"margin-top:0.5em;\">\n";

 doc += "<input style=\"width:3em;\" type=\"button\" value=\"&lt;&lt;\" onclick='firstday(\"";
 doc += name;
 doc += "\");' />\n";

 doc += "<input style=\"width:3em;\" type=\"button\" value=\"&lt;\" onclick='yesterday(\"";
 doc += name;
 doc += "\");' />\n";

 doc += "<input style=\"width:3em;\" type=\"button\" value=\"&gt;\" onclick='tomorrow(\"";
 doc += name;
 doc += "\");' />\n";

 doc += "<input style=\"width:3em;\" type=\"button\" value=\"&gt;&gt;\" onclick='lastday(\"";
 doc += name;
 doc += "\");' />\n";

 doc += "<input type=\"button\" value=\"Flip\" onclick='flipboard(\"";
 doc += name;
 doc += "\");' />\n";

 doc += "</div>\n";

 doc += "<div style=\"margin-top:0.5em;\">\n";
 doc += "<input type=\"submit\" value=\"Open in New Window\"/>\n";
 doc += "</div>\n";

 doc += "</form>\n";

 doc += "</td></tr></table>\n";

 return doc;
}

function init_playboard(name,pozycja,ruchy,whostarts,halfmove_number,flip)
{
 var width = 8;
 var height = 8;
 if (pozycja == "") pozycja = startingpozycja(width,height);

 var ret = new Array(2);
 ret[0] = 0;
 ret[1] = pozykwensuj(width,height,pozycja,ruchy,whostarts);

 if (halfmove_number<0) halfmove_number = ileruchow(ruchy);
 document.write(html_public_playboard(name,pozycja,ruchy,whostarts,halfmove_number,flip));

 var biezacapozycja = ret[1][halfmove_number];
 var deska = pozycja2deska(width,height,biezacapozycja);

 if (isflipped(name)) refresh_deska(name,deska,width,height,geta1color(name),true,true);
 else                 refresh_deska(name,deska,width,height,"dark",false,false);
 return ret;
}