//Calculate reduction (points) for move, if AIs own piece can be taken
private int reducePoints(Board board, Coord fromPos, Coord toPos)
{
int pointsToDeduct = 0;
Board tempBoard = new Board(board);
Piece temp = tempBoard.board [fromPos.xpos, fromPos.ypos];
temp.coord = toPos;
if (tempBoard.board [toPos.xpos, toPos.ypos].type != Piece.PieceType.NONE)
{
tempBoard.board [toPos.xpos, toPos.ypos] = new Piece(Piece.PieceType.NONE, toPos.xpos, toPos.ypos, Piece.PieceColor.NONE, 99);
}
tempBoard.board [fromPos.xpos, fromPos.ypos] = tempBoard.board [toPos.xpos, toPos.ypos];
tempBoard.board [toPos.xpos, toPos.ypos] = temp;
Piece.PieceColor colorToCheck;
if (color == Piece.PieceColor.WHITE)
{
colorToCheck = Piece.PieceColor.BLACK;
}
else
{
colorToCheck = Piece.PieceColor.WHITE;
}
List <Coord> test = new List <Coord>();
foreach (Piece p in tempBoard.board)
{
if (p.color == colorToCheck)
{
List <Coord> tempList = new List <Coord>();
tempList = Rules.getLegalMoves(tempBoard.board, p.coord);
foreach (Coord c in tempList)
{
test.Add(c);
}
}
}
Piece.PieceType pieceAtPos;
foreach (Piece p in tempBoard.board)
{
if (p.color == color)
{
if (test.Contains(p.coord))
{
pieceAtPos = p.type;
switch (pieceAtPos)
{
case Piece.PieceType.NONE:
if (pointsToDeduct > 0)
{
break;
}
else
{
pointsToDeduct = 0;
}
break;
case Piece.PieceType.PAWN:
if (pointsToDeduct >= 7)
{
break;
}
else
{
pointsToDeduct = 7;
}
break;
case Piece.PieceType.ROOK:
if (pointsToDeduct >= 11)
{
break;
}
else
{
pointsToDeduct = 11;
}
break;
case Piece.PieceType.KNIGHT:
if (pointsToDeduct >= 11)
{
break;
}
else
{
pointsToDeduct = 11;
}
break;
case Piece.PieceType.BISHOP:
if (pointsToDeduct >= 11)
{
break;
}
else
{
pointsToDeduct = 11;
}
break;
case Piece.PieceType.QUEEN:
if (pointsToDeduct >= 16)
{
break;
}
else
{
pointsToDeduct = 16;
}
break;
case Piece.PieceType.KING:
if (pointsToDeduct >= 15)
{
break;
}
else
{
pointsToDeduct = 15;
}
break;
}
}
}
}
return(pointsToDeduct);
}
//Calculate next AI move
public void calculateMove(Board board)
{
moves = new List <Coord[]> ();
bestPoints = -1000;
List <Coord> possibleMoves = new List <Coord> ();
//Check which moves generate the most points
foreach (Piece p in board.board)
{
if (p.color == color)
{
possibleMoves = Rules.getLegalMoves(board.board, p.coord);
Coord currentPieceCoord = p.coord;
foreach (Coord c in possibleMoves)
{
if (causeCheck(board, currentPieceCoord, c))
{
continue;
}
else
{
Piece.PieceType pieceAtToPos = board.board [c.xpos, c.ypos].type;
//Check if move puts us in a vulnerable position
int deduct = reducePoints(board, p.coord, c);
switch (pieceAtToPos)
{
case Piece.PieceType.NONE:
isBetterMove(2 - deduct, p.coord, c);
break;
case Piece.PieceType.PAWN:
isBetterMove(6 - deduct, p.coord, c);
break;
case Piece.PieceType.ROOK:
isBetterMove(10 - deduct, p.coord, c);
break;
case Piece.PieceType.KNIGHT:
isBetterMove(10 - deduct, p.coord, c);
break;
case Piece.PieceType.BISHOP:
isBetterMove(10 - deduct, p.coord, c);
break;
case Piece.PieceType.QUEEN:
isBetterMove(15 - deduct, p.coord, c);
break;
case Piece.PieceType.KING:
isBetterMove(14 - deduct, p.coord, c);
break;
}
}
}
}
}
//If we have severals moves with the same points, pick one at random
Random rnd = new Random();
int index = rnd.Next(0, moves.Count);
if (moves.Count == 0)
{
Console.WriteLine("Out of moves!!");
}
else
{
board.tryMove(moves [index] [0], moves [index] [1]);
}
}
protected override void Update(GameTime gameTime)
{
base.Update(gameTime);
MouseState ms = Mouse.GetState();
Boolean moved = false;
if (ms.LeftButton == ButtonState.Pressed)
{
if (startGameClick == false)
{
startGameClick = true;
board.startGame();
return;
}
if ((int)(ms.X) > 480)
{
board.startNewGame();
legalMoves = null;
return;
}
if (!firstClick)
{
int newxPos = (int)(ms.X / 60);
int newyPos = (int)(ms.Y / 60);
toPos = new Coord(newxPos, newyPos);
// Here we try to make a move
board.tryMove(fromPos, toPos);
legalMoves = null;
currentIndex [0] = 99;
currentIndex [1] = 99;
firstClick = true;
moved = true;
}
else
{
int xPos = (int)(ms.X / 60);
int yPos = (int)(ms.Y / 60);
if (board.board [xPos, yPos].color == board.turn)
{
fromPos = new Coord(xPos, yPos);
if (moved == false)
{
if (currentIndex [0] == xPos && currentIndex [1] == yPos)
{
currentIndex [0] = 99;
currentIndex [1] = 99;
}
else
{
currentIndex [0] = (int)(ms.X / 60);
currentIndex [1] = (int)(ms.Y / 60);
}
}
firstClick = false;
legalMoves = Rules.getLegalMoves(board.board, fromPos);
}
else
{
Console.WriteLine("NOT CORRECT TURN");
}
}
}
}