var curLineNumber;
function goToStartPosition(element) {
    var brdWrapper = $(element).parents(".chessBoard")[0];
    curLineNumber = "line0";
    $(getNextLine(brdWrapper)).click();
}

function goToFinishPosition(element) {
    var brdWrapper = $(element).parents(".chessBoard")[0];
    curLineNumber = "line0";
    var elem = brdWrapper;
    var lastElem;
    while (elem) {
        lastElem = elem;
        elem = getNextLine(elem);
    }
    $(lastElem).click();
}

function goToNextPosition(element) {
    var brdWrapper = $(element).parents(".chessBoard")[0];
    if (curBrdWrapper && (curBrdWrapper.id == brdWrapper.id)) {
        curLineNumber = findLineNum(curMoveElement);
        $(getNextLine(curMoveElement)).click();
    }
    else {
        if (brdWrapper.curMoveElement) {
            curLineNumber = findLineNum(brdWrapper.curMoveElement);
            $(getNextLine(brdWrapper.curMoveElement)).click();
        }
        else {
            curLineNumber = "line0";
            var nextElem = getNextLine(getNextLine(brdWrapper));
            if (nextElem)
                $(nextElem).click();
            else
                $(getNextLine(brdWrapper)).click();
        }

    }   
    
}


function goToPrevPosition(element) {
    var brdWrapper = $(element).parents(".chessBoard")[0];
    if (curBrdWrapper && (curBrdWrapper.id == brdWrapper.id)) {
        curLineNumber = findLineNum(curMoveElement);
        $(getPrevLine(curMoveElement)).click();
    }
    else {
        if (brdWrapper.curMoveElement) {
            curLineNumber = findLineNum(brdWrapper.curMoveElement);
            $(getPrevLine(brdWrapper.curMoveElement)).click();
        }
        else {
            curLineNumber = "line0";
            $(getNextLine(brdWrapper)).click();
        }
    }

}

function findLineNum(elem)
{
    var classes = elem.className.split(/\s/);
    for (var i = 0, len = classes.length; i < len; i++) 
        if (/^line/.test(classes[i])) return classes[i];
    return null;
}


function classStartsWithLine(elem) {
    var classes = elem.className.split(/\s/);
    for (var i = 0, len = classes.length; i < len; i++) {
        if (classes[i] == "line0") {
            curLineNumber = "line0";
            return true;
        }
        if (classes[i] == curLineNumber) return true;
    }
     
    return false;
}

function findFirstLine(elems) {
    for (var i = 0; i < elems.length; i++) {
        if (classStartsWithLine(elems[i]))
            return elems[i];
    }
    return null;
}

function findLastLine(elems) {
    for (var i = elems.length - 1; i >= 0; i--) {
        if (classStartsWithLine(elems[i]))
            return elems[i];
    }
    return null;
}

function getNextLineDown(elem) {    
    var next = $(elem).nextAll();
    if (next.length != 0)
    {
        for (var i = 0; i < next.length; i++) {
            if (classStartsWithLine(next[i]))
                return next[i];
            var child = $(next[i]).children();
            if (child.length > 0) {
                var firstLine = findFirstLine(child);
                if (firstLine)
                    return firstLine;
                var found = getNextLineDown(child[0]);
                if (found)
                    return found;
            }
        }
    }
    return null;
}

function getPrevLineDown(elem) {
    var prev = $(elem).prevAll();    
    if (prev.length != 0) {
        for (var i = 0; i < prev.length; i++) {
            if (classStartsWithLine(prev[i]))
                return prev[i];
            var child = $(prev[i]).children();
            if (child.length > 0) {
                var lastLine = findLastLine(child);
                if (lastLine)
                    return lastLine;
                var found = getPrevLineDown(child[i]);
                if (found)
                    return found;
            }
        }
    }
    return null;

}

function getPrevLine(elem) {    
    var result = getPrevLineDown(elem);
    var parent = $(elem).parent();
    while (!result && (parent.length > 0) && (!parent.hasClass('section'))) {
        result = getPrevLineDown(parent);
        if (!result)
            parent = parent.parent();
    }
    return result;
}

function getNextLine(elem) {
    var result = getNextLineDown(elem);
    var parent = $(elem).parent();
    while (!result && (parent.length > 0) && (!parent.hasClass('section'))) {
        result = getNextLineDown(parent);
        if (!result)
            parent = parent.parent();
    }
    return result;
}


var curMoveElement;
var curBrdWrapper;
$(document).keydown(function (ev) {
    if (ev.ctrlKey) {
        var elem;
        if (ev.keyCode == 39) {
            elem = $("#next_page");
        }
        if (ev.keyCode == 37) {
            elem = $("#prev_page");
        }
        if (!elem)
            return true;
        if (elem.length > 0)
            window.location = $(elem[0]).attr("href")
        return false;
    }
    else {
        if (!curMoveElement)
            return true;
        var elems;
        curLineNumber = findLineNum(curMoveElement);
        if (ev.keyCode == 39) {            
            elems = $(getNextLine(curMoveElement));
        }
        if (ev.keyCode == 37) {
            elems = $(getPrevLine(curMoveElement));
        }
        if (!elems)
            return true;
        if (elems.length > 0)
            $(elems[0]).click();
        return false;
    }
});

function loadMove(fen, element, move) {
    if (curMoveElement) {
        $(curMoveElement).removeClass('current_move');
    }
    curMoveElement = element;
    curMoveElement.className += ' current_move';
    $(curMoveElement).addClass('current_move');
    element = $(element).parents('.section')[0];
    if (!element)
        element = document;
    var brdWrapper = $(element).find('.chessBoard')[0];
    curBrdWrapper = brdWrapper;
    brdWrapper.curMoveElement = curMoveElement;
    brdWrapper.board.loadFEN(fen);    
    brdWrapper.gui.drawBoardPosition();
    if (move) {
        var fromX = move.charAt(0);
        var fromY = move.charAt(1);
        var toX = move.charAt(2);
        var toY = move.charAt(3);
        var piece = brdWrapper.board.squares[toX][toY].piece;
        var knight = piece ? (piece.name == "knight" ? true : false) : false;
        brdWrapper.boardMarkers.notaDrawArrow(fromX, fromY, toX, toY, knight);
    }

}

function promoteTo(pieceName, element) {
    var brdWrapper = $(element).parent().parent().parent()[0];
    var promBox = brdWrapper.promotionView;    
    $(promBox).fadeOut('slow');
    mv = $(promBox).data('move');
    var c = pieceName.charAt(0).toLowerCase();
    if (pieceName == "knight")
        c = 'n';
    mv = mv + c;

    brdWrapper.playController.MoveMade(mv, function (result) {
        if (result) {
            brdWrapper.gui.makeMove('pawn', mv.charAt(1), mv.charAt(2), mv.charAt(3),
                mv.charAt(4), pieceName);
        }
        else {
            brdWrapper.gui.drawBoardPosition();
        }
        brdWrapper.gui.BoardDisabled = false;
    });
      
}

function BoardController() {
    // Rotates the board
    this.flipBoard =
	function (boardId) {
	    var brdWrapper = $(document).find('#' + boardId)[0];
	    if (brdWrapper.gui.flipped)
	        brdWrapper.gui.flipped = false;
	    else
	        brdWrapper.gui.flipped = true;
	    $(brdWrapper.whiteIndicator).addClass('black');
	    $(brdWrapper.whiteIndicator).removeClass('white');
	    $(brdWrapper.blackIndicator).removeClass('black');
	    $(brdWrapper.blackIndicator).addClass('white');

	    var temp = brdWrapper.whiteIndicator;
	    brdWrapper.whiteIndicator = brdWrapper.blackIndicator;
	    brdWrapper.blackIndicator = temp;

	    brdWrapper.gui.drawBoardPosition();
	    brdWrapper.boardMarkers.redrawMarkers();
	}

	this.loadMove =
    function (boardId, moveId) {
        var brdWrapper = $(document).find('#' + boardId)[0];
        var game = brdWrapper.games[0];

        if (moveId == "end") {
            moveId = game.lastMove;
        }
        var fen = game.FENs[game.displayNotation[moveId]["fenlink"].variation][game.displayNotation[moveId]["fenlink"].number];
        brdWrapper.board.loadFEN(fen);
        game.currPosition = fen;
        var oldid = game.notationMove;
        game.notationMove = moveId;

        brdWrapper.gui.displayMove(game, brdWrapper.board, oldid);

        if (moveId != "start") {
            var fromX = game.displayNotation[moveId]["fromto"].fromX;
            var fromY = game.displayNotation[moveId]["fromto"].fromY;
            var toX = game.displayNotation[moveId]["fromto"].toX;
            var toY = game.displayNotation[moveId]["fromto"].toY;

            var knight = (game.displayNotation[moveId]["token"].charAt(0) == "N" ? true : false);

            brdWrapper.boardMarkers.notaDrawArrow(fromX, fromY, toX, toY, knight);            
        } else
            brdWrapper.boardMarkers.clearMarkers();                    

    }
}


function GUI(boardWrapper) {
    var board = boardWrapper.board;
    var boardTable = boardWrapper.boardTable;
    var boardMarkers = boardWrapper.boardMarkers;
    var lang = chessBoardLang;
	var numbers = [8, 7, 6, 5, 4, 3, 2, 1];
	var letters = ["a", "b", "c", "d", "e", "f", "g", "h"];
	var letter = [];
	var canvas = null;
	letter["a"] = 1;
	letter["b"] = 2;
	letter["c"] = 3;
	letter["d"] = 4;
	letter["e"] = 5;
	letter["f"] = 6;
	letter["g"] = 7;
	letter["h"] = 8;

	this.IsFinished = false;
	this.BoardDisabled = false;

	// If board is flipped
	this.flipped = false;

	this.addNotaMove = function (text, fen, move) {
	    if (!this.notation) return;

	    var moveString = '<span data-fen="' + fen + '"';
	    if (move) {
	        moveString += ' data-move="' + move + '"';
	    }
	    moveString += ' class="line">' + text + '</span>';

	    this.notation.innerHTML += moveString + ' ';
	}

	this.makeMove = function (piece, fromX, fromY, toX, toY, promoteTo) {
	    var moveNumber = board.fullMoves;

	    var move = board.formMove(piece, fromX, fromY, toX, toY, promoteTo);
	    board.moveHandler(piece, fromX, fromY, toX, toY, promoteTo);
	    this.drawBoardPosition(board);

	    if (this.notation) {
	        var fen = board.currentFEN();

            var moveText = '';

            if (moveNumber == 1 && !this.notation.notEmpty) {
	            this.notation.notEmpty = true;
	            moveText += moveNumber + '.';
	            if (board.currentMove == 'white')
	                moveText += '..';
	            moveText += ' ';
	        }
	        else if (board.currentMove == 'black') {
	            moveText += moveNumber + '. ';
	        }

	        moveText += move.AsString();

	        this.addNotaMove(moveText, fen, move.LongString());
	    }
	}

    this.parseMove =
	function (token, varNum, aIsFinished) {
	    var moveArray = token.match(/([RBQKPN])?([a-h])?([1-8])?([x])?([a-h])([1-8])([=]?)([qnrbQNRB]?)([+#]?)/);	    
	    var fromX;
	    var fromY;
	    var toX;
	    var toY;
	    var piece;
	    var promotion;
	    var promoteTo;

	    fromX = moveArray[2];
	    fromY = moveArray[3];

	    piece = board.squares[fromX][fromY].piece.name;
	    this.IsFinished = aIsFinished;

	    toX = moveArray[5];
	    toY = moveArray[6];

	    if (moveArray[8]) {
	        promotion = true;
	        switch (moveArray[8].toLowerCase()) {
	            case "r":
	                promoteTo = "rook";
	                break;
	            case "b":
	                promoteTo = "bishop";
	                break;
	            case "q":
	                promoteTo = "queen";
	                break;
	            case "n":
	                promoteTo = "knight";
	                break;
	            default:
	                break;
	        }
	    } else {
	        promotion = false;
	        promoteTo = '';
	    }

	    // Make piece move + animation	   

	    var castle = board.castleMove(piece, fromX, toX);
	    if (castle.castling) {
	        this.AnimateMove(piece, fromX, fromY, toX, toY, promoteTo, 0, 600);
	        this.AnimateMove(castle.piece, castle.fromX, castle.fromY, castle.toX, castle.toY, null, -1, 600);
	    } else {
	        this.AnimateMove(piece, fromX, fromY, toX, toY, promoteTo, 0, 600);
	    }
	}

    // if varLvl = -1 => no move needed
	this.AnimateMove =
    function (piece, fromX, fromY, toX, toY, promoteTo, varLvl, AnimDuration) {
        var animateFromPiece = $(boardTable).find(".piece" + fromX + fromY)[0];
        var AnimateFromSquare = this.getGUISquare(fromX, fromY);
        var posSquare = $(AnimateFromSquare).position();
        var posAnimate = $(animateFromPiece).position();
        animateFromPiece.style.left = posAnimate.left + "px";
        animateFromPiece.style.top = posAnimate.top + "px";
        var offsetX = posAnimate.left - posSquare.left;
        var offsetY = posAnimate.top - posSquare.top;
        animateFromPiece.style.position = 'absolute';
        var AnimateToPiece = this.getGUISquare(toX, toY);
        var posToAnimate = $(AnimateToPiece).position();
        
        animateFromPiece.dataPiece = piece;
        animateFromPiece.dataFromX = fromX;
        animateFromPiece.dataFromY = fromY;
        animateFromPiece.dataToX = toX;
        animateFromPiece.dataToY = toY;
        animateFromPiece.dataPromoteTo = promoteTo;
        animateFromPiece.dataVarLvl = varLvl;
        $(animateFromPiece).animate({
            "left": posToAnimate.left + offsetX,
            "top": posToAnimate.top + offsetY
        }, AnimDuration, function () {
            if (parseInt(this.dataVarLvl) == -1)
                return;
            boardWrapper.gui.makeMove(this.dataPiece, this.dataFromX, parseInt(this.dataFromY),
                        this.dataToX, parseInt(this.dataToY), this.dataPromoteTo);
        });

    }

    this.blinkPiece =
    function (square) {
        x = square.charAt(0);
        y = square.charAt(1);        
        var animateFromPiece = $(boardTable).find(".piece" + x + y)[0];
        $(animateFromPiece).blink({
            speed: 200,
            blinks: 4
        });
    }

    this.ShowActions =
	function (Actions) {
	    boardMarkers.clearMarkers();
	    var element = $(document).find("#puzzleMessage")[0];
	    if (Actions.length == 0) {
	        if (element != null) {
	            if (this.BoardDisabled)
	                element.innerHTML = lang.yourTurn;
	        }
	        return;
	    }
	    var NeedDisable = true;
	    if (this.BoardDisabled)
	        NeedDisable = false;
	    this.BoardDisabled = true;

	    if ((Actions.length > 0) && (Actions[0].charAt(0) == 'p')) {
	        if (board.currentFEN(true) == Actions[0].substr(1))
	            Actions.splice(0, 1);
	    }

	    if (Actions.length == 0) {
	        if (NeedDisable) {
	            this.BoardDisabled = false;
	        }
	        else {
	            if (element != null)
	                element.innerHTML = lang.yourTurn;
	        }
	    }

	    else {
	        $(this).everyTime(800, 'MoveTimer', function (i) {
	            if (i == Actions.length + 1) {
	                if (NeedDisable) {
	                    this.BoardDisabled = false;
	                    if (element != null)
	                        element.innerHTML = lang.yourTurn;
	                }

	                if (this.TaskFinished) {
	                    $('.task_notation .line').addClass('active').live('click', function () {
	                        loadMove($(this).attr('data-fen'), this, $(this).attr('data-move'));
	                    });
	                }
	            }
	            else
	                if (Actions[i - 1] != undefined)
	                    switch (Actions[i - 1].charAt(0)) {
	                    case "p":
	                        {
	                            board.loadFEN(Actions[i - 1].substr(1));
	                            boardWrapper.gui.drawBoardPosition();
	                            break;
	                        }
	                    case "m":
	                        {
	                            if (element != null && !$(element).hasClass('solved')) {
	                                element.innerHTML = '<span class="ajaxload right">' + lang.animating + '</span>';
	                            }
	                            boardWrapper.gui.parseMove(Actions[i - 1].substr(1), 0);
	                            break;
	                        }
	                    case "b":
	                        {
	                            boardWrapper.gui.blinkPiece(Actions[i - 1].substr(1));
	                            break;
	                        }
	                    case "x":
	                        {
	                            boardWrapper.boardMarkers.drawMarkers(Actions[i - 1].substr(1));
	                            break;
	                        }
	                    default:
	                        {
	                            break;
	                        }
	                }
	        }, Actions.length + 1);
	    }

	}

	var firstDraw = true;

	this.drawBoardPosition =
	function () {
	    if (!firstDraw) {
	        $(boardTable).find('td').children('.piece').remove();
	    }
	    else {
	        firstDraw = false;
	    }

	    for (var i = 0; i < board.pieces.length; i++) {
	        var piece = board.pieces[i];
	        var square = piece.square;
	        if (square != undefined) {
	            var GUIsquare = this.getGUISquare(square.x, square.y);
	            var pieceImg = document.createElement("div");
	            pieceImg.className = "piece" + square.x + square.y + ' piece ' + piece.color.charAt(0) + piece.name;
	            GUIsquare.appendChild(pieceImg);
	        }
	    }

	    if (boardMarkers != null)
	        boardMarkers.clearMarkers();

	    if (board.currentMove == 'white') {
	        $(boardWrapper.blackIndicator).hide();
	        $(boardWrapper.whiteIndicator).show();
	    }
	    else {
	        $(boardWrapper.blackIndicator).show();
	        $(boardWrapper.whiteIndicator).hide();
	    }

	    if (!firstDraw || this.flipped)
	        this.drawCoordinates();
	}

	// Draws the coordinates according to this.flipped state
	this.drawCoordinates =
	function () {
	    var lttr;
	    var nmbr;
	    for (var i = 0; i < letters.length; i++) {
	        if (this.flipped) {
	            lttr = letters[7 - i];
	            nmbr = i + 1;
	        } else {
	            lttr = letters[i];
	            nmbr = 8 - i;
	        }
	        
	        var holder = boardTable.rows[0].cells[i + 1];
	        holder.innerHTML = lttr.toUpperCase();
	        holder = boardTable.rows[9].cells[i + 1];
	        holder.innerHTML = lttr.toUpperCase();
	        holder = boardTable.rows[i + 1].cells[0];
	        holder.innerHTML = nmbr;
	        holder = boardTable.rows[i + 1].cells[9];
	        holder.innerHTML = nmbr;
	    }
	}

	this.displayMove =
	function (game, board, oldid) {
	    this.drawBoardPosition(game, board);
	}

	// Returns the GUI square reference given the board coordinates;
	this.getGUISquare =
	function (x, y) {
	    if (!this.flipped) {
	        x = letter[x];
	        y = 9 - y;
	    } else {
	        x = 9 - letter[x];
	    }

        element = boardTable.rows[y].cells[x];

	    return element;
	}

	// Returns the board coordinates given the id of GUI square
	this.getSquare =
	function (className) {
	    var startIndex;
	    if (className.match(/piece/)) {
	        startIndex = className.indexOf('piece');
	        return { x: className.charAt(startIndex + 5), y: className.charAt(startIndex + 6) };
	    }
	    startIndex = className.indexOf("square");
	    if (!this.flipped) {
	        x = letters[className.charAt(startIndex + 6) - 1];
	        y = 9 - className.charAt(startIndex + 7);
	    } else {
	        x = letters[8 - className.charAt(startIndex + 6)];
	        y = className.charAt(startIndex + 7);
	    }
	    return { x: x, y: y };
	}
}