/************************************************************************************************************
Chess Fen Viewer
Copyright (C) 2007  DTHMLGoodies.com, Alf Magne Kalleland

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA

Dhtmlgoodies.com., hereby disclaims all copyright interest in this script
written by Alf Magne Kalleland.

Alf Magne Kalleland, 2007
Owner of DHTMLgoodies.com


************************************************************************************************************/

var DHTMLGoodies = new Object();
if(!String.trim)String.prototype.trim = function() { return this.replace(/^\s+|\s+$/, ''); };

/* The widget */
DHTMLGoodies.ChessFen = function(props)
{
  var divBoard;
  var cssPath;
  var parentRef;
  var squareSize;
  var imageFolder;
  var isOldMSIE;
  var boardLabels;
  var flipBoardWhenBlackToMove;

  var pieceType;

  this.pieceType = 'book';
  this.boardType = 'Brown';
  this.squareSize = 45;
  this.isOldMSIE = (navigator.userAgent.toLowerCase().match(/msie\s[0-6]/gi))?true:false;
  this.isOpera = (navigator.userAgent.toLowerCase().indexOf('opera')>=0)?true:false;

  //this.cssPath = 'static.chess.com';
  this.parentRef = document.body;
  this.staticPath = 'static.chess.com';
  this.boardLabels = true;
  this.flipBoardWhenBlackToMove = true;

  this.classesMap = {'20' : 'bg_piece_', '30' : 'bg_piece2_'};

  if(props)this.__setInitProps(props);
  this.init();

}


DHTMLGoodies.ChessFen.prototype = {
  __chessFenCSSLoaded : false,

  __setInitProps : function(props)
  {
    //if(props.cssPath)this.cssPath = props.cssPath;
    if(props.staticPath)this.staticPath = props.staticPath;
    if(props.squareSize)this.squareSize = props.squareSize;
    if(props.boardLabels || props.boardLabels===false)this.boardLabels = props.boardLabels;
    if(props.flipBoardWhenBlackToMove || props.flipBoardWhenBlackToMove===false)this.flipBoardWhenBlackToMove = props.flipBoardWhenBlackToMove;
    if(props.pieceType)this.pieceType = props.pieceType;
    if(props.boardType)this.boardType = props.boardType;
  }
  ,
  setSquareSize : function(squareSize)
  {
    this.squareSize = squareSize;
  }
  ,
  setPieceType : function(pieceType)
  {
    this.pieceType = pieceType;
  }
  ,
  init : function()
  {
    this.__loadCss(this.staticPath);

  }
  ,
  setFlipBoardWhenBlackToMove : function(flipBoardWhenBlackToMove)
  {
    this.flipBoardWhenBlackToMove = flipBoardWhenBlackToMove;
  }
  ,
  getWhoToMove : function()
  {
    return this.whoToMove;
  }
  ,
  setBoardLabels : function(boardLabels)
  {
    this.boardLabels = boardLabels;
  }
  ,
  __setWhoToMove : function(fenString)
  {
    var items = fenString.split(/\s/g);
    this.whoToMove = items[1].trim();
  }
  ,
  loadFen : function(fenString,element)
  {
    this.__setWhoToMove(fenString);

    element = this.__getEl(element);
    element.innerHTML = '';
    var boardOuter = document.createElement('DIV');
    boardOuter.className = 'ChessBoard' + this.boardType + this.squareSize;
    boardOuter.style.position = 'relative';
    var board = document.createElement('DIV');
    board.className = 'ChessBoardInner' + this.boardType + this.squareSize;

    if(this.boardLabels){
      this.__addBoardLabels(boardOuter);
      boardOuter.appendChild(board);
      board.style.position = 'absolute';
      board.style.top='0px';
      board.style.right='0px';
      element.appendChild(boardOuter);
    }else{
      board.style.position = 'relative';
      element.appendChild(board);
    }
    this.__loadFen(fenString,board);

  }
  ,
  __addBoardLabels : function(boardOuter)
  {
    var letters = 'ABCDEFGH';
    for(var no=1;no<=8;no++){
      var file = document.createElement('DIV');
      file.style.position = 'absolute';
      file.style.right = ((8-no) * this.squareSize) + 'px';
      file.style.bottom = '0px';
      file.innerHTML = letters.substr((no-1),1);
      file.style.textAlign = 'center';
      file.style.width = this.squareSize + 'px';
      boardOuter.appendChild(file);
      file.className = 'ChessBoardLabel ChessBoardLabel'+this.squareSize;

      var rank = document.createElement('DIV');
      rank.style.position = 'absolute';
      rank.style.left = '0px';
      rank.style.top = ((8-no) * this.squareSize) + 'px'; ;
      rank.innerHTML = no;
      rank.style.height = this.squareSize + 'px';
      rank.style.lineHeight = this.squareSize + 'px';
      boardOuter.appendChild(rank);
      rank.className = 'ChessBoardLabel ChessBoardLabel'+this.squareSize;

      if(this.whoToMove=='b' && this.flipBoardWhenBlackToMove){
        rank.innerHTML = 9-no;
        file.innerHTML = letters.substr((8-no),1);
      }
    }

  }
  ,
  // Load Forsyth-Edwards Notation (FEN)
  __loadFen : function(fenString,boardEl)
  {
    var items = fenString.split(/\s/g);
    var pieces = items[0];

    var currentCol = 0;
    for(var no=0;no<pieces.length;no++){
      var character = pieces.substr(no,1);

      if(character.match(/[A-Z]/i)){  /* White pieces */
        var boardPos = this.__getBoardPosByCol(currentCol);
        var piece = document.createElement('DIV');
        piece.style.position = 'absolute';
        piece.style.left = boardPos.x + 'px';
        piece.style.top = boardPos.y + 'px';

        if(character.match(/[A-Z]/)){ /* White pieces */
          var color = 'w';
        }
        if(character.match(/[a-z]/)){ /* Black pieces */
          var color = 'b';
        }
    piece.className = this.classesMap[this.squareSize] + color + character.toLowerCase() + ' p' + this.squareSize;
        boardEl.appendChild(piece);
        currentCol++;

      }
      if(character.match(/[0-8]/))currentCol+=character/1;
    }


  }
  ,
  /* Starting from the top */
  /* 1-64 */
  __getBoardPosByCol : function(col)
  {
    var squareColor = 'w';
    var rank = 0;
    while(col>=8){
      rank++;
      col-=8;
      if (squareColor == 'w')
        squareColor = 'b';
      else
        squareColor = 'w';
    }
    var retArray = new Object();

    for (var n=1; n <= col; n++) {
      if (squareColor == 'w')
        squareColor = 'b';
      else
        squareColor = 'w';
    }

    if(this.whoToMove=='b' && this.flipBoardWhenBlackToMove){
      col = 7-col;
      rank = 7-rank;
    }

    retArray.x = col* this.squareSize;
    retArray.y = rank * this.squareSize;
    retArray.color = squareColor;
    return retArray;


  }
  ,
  __loadCss : function(cssFile)
  {
    if (!DHTMLGoodies.__chessFenCSSLoaded) {
      var lt = document.createElement('LINK');
      var jsVersionString = (typeof(Config) != 'undefined') ? '.v' + Config['application.version'] : '';
        lt.href = '//' + cssFile + '/css/chessfen' + jsVersionString + '.css';
        lt.rel = 'stylesheet';
        lt.media = 'screen';
        lt.type = 'text/css';
        document.getElementsByTagName('HEAD')[0].appendChild(lt);
  DHTMLGoodies.__chessFenCSSLoaded = true;
    }
  }
  ,
  __getEl : function(elRef)
  {
    if(typeof elRef=='string'){
      if(document.getElementById(elRef))return document.getElementById(elRef);
      if(document.forms[elRef])return document.forms[elRef];
      if(document[elRef])return document[elRef];
      if(window[elRef])return window[elRef];
    }
    return elRef; // Return original ref.
  }
  ,
  correctPng : function(el)
  {
    el = this.__getEl(el);
    var img = el;
    var oldSrc = img.src;
    img.src = "//" + this.staticPath + "/js/chess/images/blank.gif";
        img.runtimeStyle.filter="progid:DXImageTransform.Microsoft.AlphaImageLoader(src='" + oldSrc + "',sizingMethod='scale')";
  }
}