// $Id: squareclicked.js,v 1.3 2009/02/26 17:59:18 kramos Exp $

// this is the main function that interacts with the user everytime they click on a square

  /* called whenever a square is clicked on */
  var is1stClick = true;

  function squareClickedFirst(row, col, isEmpty, curColor)
  {
    if (getPieceColor(board[row][col]) == curColor)
    {
      document.gamedata.fromRow.value = row;
      document.gamedata.fromCol.value = col;

      highlight(row, col);

      is1stClick = false;
    }
    else
      alert("I'm sorry, but you play the " + curColor +" pieces.");

  }

  function squareClickedSecond(row, col, isEmpty, curColor)
  {
    unhighlight(document.gamedata.fromRow.value, document.gamedata.fromCol.value);
    is1stClick = true;

    if ((document.gamedata.fromRow.value == row)
      && (document.gamedata.fromCol.value == col))
    {
      document.gamedata.fromRow.value = "";
      document.gamedata.fromCol.value = "";
    }
    else
    {
      /* if, on a player's second click, they click on one of their own piece */
      /* act as if he was clicking for the first time (ie: select it) */
      if (board[row][col] != 0 )
        if (getPieceColor(board[row][col]) == curColor)
        {
          squareClickedFirst(row, col, isEmpty, curColor);
          return null;
        }

      var fromRow = parseInt(document.gamedata.fromRow.value);
      var fromCol = parseInt(document.gamedata.fromCol.value);
      document.gamedata.toRow.value = row;
      document.gamedata.toCol.value = col;

      if (isValidMove(fromRow, fromCol, row, col))
      {
	/** kj changes -  calculate matching board coordinates **/
	var fromRowC = Number(fromRow) + 1;
	var fromColC = String.fromCharCode(Number(fromCol) + 97);
        var toRowC =  row + 1;
        var toColC =  String.fromCharCode(col + 97);

	/** kj changes -  add confirm move message **/
	if (confirm("Confirm move from " + fromColC + fromRowC + " to " + toColC + toRowC + " ? \n\nOK=Yes - Cancel=No")){

        if (DEBUG)
          alert("Move is valid, updating game...");

        // Note the move in the history of the game
        // Note that this entry won't be used unless numMoves is incremented
        // Important: Some checks below need this entry, while it would cause others to fail
        // Therefore numMoves must be locally incremented and then reset again when it's needed
        var idx = numMoves + 1;
        chessHistory[idx] = new Array();
        chessHistory[idx][CURPIECE] = thePiece;
        chessHistory[idx][CURCOLOR] = curColor;
        chessHistory[idx][FROMROW] = fromRow;
        chessHistory[idx][FROMCOL] = fromCol;
        chessHistory[idx][TOROW] = row;
        chessHistory[idx][TOCOL] = col;

        var ennemyColor = "white";
        if (curColor == "white")
          ennemyColor = "black";
        var isCapture = (board[row][col] != 0);
        var thePiece = getPieceName(board[fromRow][fromCol]);

        /* update board with move (client-side) */
        board[row][col] = board[fromRow][fromCol];
        board[fromRow][fromCol] = 0;

        /* if this is a castling move the rook must also be moved */
        if ((thePiece == 'king') && (Math.abs(col - fromCol) == 2))
        {  // The king only moves two squares when castling
          var rookCol = 0;
          var rookToCol = 3
          if (col - fromCol == 2)
          {  // Kingside castling (would be == -2 if queenside)
            rookCol = 7;
            rookToCol = 5;
          }
          board[row][rookToCol] = board[row][rookCol];
          board[row][rookCol] = 0;
        }
        else if((thePiece == 'pawn') && (col != fromCol) && (!isCapture))
        {  /* if this is an en passant capture, the captured pawn must be removed */
          board[fromRow][col] = 0;
        }

        if (isInCheck(ennemyColor))
        {
          document.gamedata.isInCheck.value = "true";
          if(thePiece == 'pawn' && Math.abs(row - fromRow) == 2)  // Pawn double advance
            var epCol = col;  // The column of the en passant square
          else
            var epCol = -1;
          document.gamedata.isCheckMate.value = isCheckMate(ennemyColor, epCol);
        }
        else
        {  // Not in check
          document.gamedata.isInCheck.value = "false";
        }
        //document.gamedata.submit();

        $.post("?q=chess/writeJSboard", { 'fromCol': document.gamedata.fromCol.value, 'fromRow': document.gamedata.fromRow.value, 'isCheckMate': document.gamedata.isCheckMate.value, 'isInCheck': document.gamedata.isInCheck.value, 'toCol': document.gamedata.toCol.value, 'toRow': document.gamedata.toRow.value },
            function(data) {
              eval(data);
              eval('var theBoard = htmlBoard();');
              chessboard_populate();
              if(isPromoting)
                window.location.replace('?q=chess/game');
            });
	}else{
		//confirm move denied...
	}

      }
      else
      {
        document.gamedata.toRow.value = "";
        document.gamedata.toCol.value = "";

        alert("Invalid move:\n" + errMsg);
      }
    }
  }

  function squareClicked(squareObj)
  {
    var square = squareObj.id.slice(3);
    square = parseInt(square);
    var col = square % 8;
    var row = (square-col) / 8;
    var isEmpty = (board[row][col] == 0);
    if (DEBUG)
      alert('squareClicked -> row = ' + row + ', col = ' + col + ', isEmpty = ' + isEmpty);

    var curColor = "black";
    if ((numMoves == -1) || (numMoves % 2 == 1))
      curColor = "white";

    if (is1stClick)
    { // No piece has been clicked yet
      if(!isEmpty)  // Not an empty square
        squareClickedFirst(row, col, isEmpty, curColor);
      else  // Clicked on an empty square
        return;
    }
    else  // The second click. A piece has already been marked with the first click
      squareClickedSecond(row, col, isEmpty, curColor);
  }