public AlphaBetaReturnValue(int value, MoveResult m, int maxDepth)
{
Value = value;
Move = m;
Depth = maxDepth;
}
// moves a piece given a MoveResult and color
public TurnResult MovePiece(MoveResult move, PieceColor color)
{
var piece = Pieces.GetPieceForColorAtLocation(move.OriginalPieceLocation, color);
Debug.Assert(piece != null);
piece.X = move.FinalPieceLocation.X;
piece.Y = move.FinalPieceLocation.Y;
if (move.Type == MoveType.Jump)
{
for (var i = 0; i < move.JumpResults.Count; i++)
{
//kills any jumped pieces
var jumpResult = move.JumpResults[i];
var killedPiece = Pieces.GetPieceForColorAtLocation(jumpResult.JumpedLocation,
color == PieceColor.Black
? PieceColor.Red
: PieceColor.Black);
Pieces.KillPiece(killedPiece, _internalTurnBookKeeping);
}
}
_internalTurnBookKeeping++;
return TurnResult.Finished;
}
// reverts a given move and returns to the state that it was before that move
public void RevertMove(MoveResult move, PieceColor color)
{
if(move.Type == MoveType.Jump)
{
for (var i = 0; i < move.JumpResults.Count; i++)
{
var jumpResult = move.JumpResults[i];
var resPiece = Pieces.GetCapturedPieceForColorAtLocation(jumpResult.JumpedLocation,
color == PieceColor.Black
? PieceColor.Red
: PieceColor.Black);
Pieces.RevivePiece(resPiece);
}
}
var piece = Pieces.GetPieceAtPosition(move.FinalPieceLocation);
piece.X = move.OriginalPieceLocation.X;
piece.Y = move.OriginalPieceLocation.Y;
_internalTurnBookKeeping--;
}
// returns the possible moves for a given piece, if jumpsOnly is set, then only jumps will be considered
public List<MoveResult> GetAvailableMovesForPiece(CheckersPiece piece, bool jumpsOnly)
{
var moveResults = new List<MoveResult>();
var jumpsAvailable = GetAvailableJumps(piece.X, piece.Y, piece.Color);
if (jumpsAvailable.Count > 0 || jumpsOnly)
{
for (var i = 0; i < jumpsAvailable.Count; i++)
{
var jump = jumpsAvailable[i];
var mr = new MoveResult(MoveType.Jump, piece, jump.FinalLocation.X, jump.FinalLocation.Y)
{JumpResults = jump.LocationsJumped};
moveResults.Add(mr);
}
return moveResults; //user must make a jummp
}
//possible forward moves must be considered too
var possibleEndValues = new List<Location>
{
new Location(piece.X - 1, piece.Y + (int)piece.Forward),
new Location(piece.X + 1, piece.Y + (int)piece.Forward)
};
for (var i = possibleEndValues.Count - 1; i >= 0; i--)
{
var p = possibleEndValues[i];
//remove invalid final locations (piece is there or the location is invalid)
if (!TileBoard.IsValidLocation(p) || Pieces.GetPieceAtPosition(p) != null)
possibleEndValues.RemoveAt(i);
}
for (var i = 0; i < possibleEndValues.Count; i++)
{
var possibleEndValue = possibleEndValues[i];
moveResults.Add(new MoveResult(MoveType.Forward, piece, possibleEndValue.X, possibleEndValue.Y));
}
return moveResults;
}