public void CloneTest_WhenCloning_ThenReturnsCopyButDifferentInstance()
{
BoardState target = new BoardState(null);
target.SetPiece(0, 0, Piece.X);
var copiedBoard = target.Clone();
Assert.AreEqual(copiedBoard.GetPiece(0, 0), Piece.X);
target.SetPiece(0, 1, Piece.X);
Assert.AreEqual(target.GetPiece(0, 1), Piece.X);
Assert.AreEqual(copiedBoard.GetPiece(0, 1), Piece.Empty);
}
public void CloneTest_WhenCloning_ThenReturnsCopy()
{
BoardState target = new BoardState(null);
target.SetPiece(0, 0, Piece.X);
var copiedBoard = target.Clone();
Assert.AreEqual(copiedBoard.GetPiece(0, 0), Piece.X);
}
/// <summary>
/// Does a computer move using minimax algorithm.
/// http://neverstopbuilding.com/minimax
/// </summary>
public int DoMove(Piece piece, BoardState board)
{
if (board.IsWinner(Piece.X))
{
return(10);
}
else if (board.IsWinner(Piece.O))
{
return(-10);
}
else if (board.IsDraw())
{
return(0);
}
else
{
var boardStatesForNextMove = new List <BoardState>();
var emptyPositions = GetEmptyFields(board);
var scores = new List <int>();
foreach (var move in emptyPositions)
{
BoardState boardForThisMove = board.Clone();
boardForThisMove.SetPiece(move.X, move.Y, piece);
boardStatesForNextMove.Add(boardForThisMove);
Piece nextPiece = piece == Piece.X ? Piece.O : Piece.X;
scores.Add(DoMove(nextPiece, boardForThisMove));
}
int max = scores.Max();
int maxIndex = scores.IndexOf(max);
int min = scores.Min();
int minIndex = scores.IndexOf(min);
if (piece == Piece.X)
{
var selectedMove = emptyPositions[maxIndex];
board.SetPiece(selectedMove.X, selectedMove.Y, piece);
return(max);
}
else
{
var selectedMove = emptyPositions[minIndex];
board.SetPiece(selectedMove.X, selectedMove.Y, piece);
return(min);
}
}
}
/// <summary>
/// Does a computer move using minimax algorithm.
/// http://neverstopbuilding.com/minimax
/// </summary>
public int DoMove(Piece piece, BoardState board)
{
if (board.IsWinner(Piece.X))
{
return 10;
}
else if (board.IsWinner(Piece.O))
{
return -10;
}
else if (board.IsDraw())
{
return 0;
}
else
{
var boardStatesForNextMove = new List<BoardState>();
var emptyPositions = GetEmptyFields(board);
var scores = new List<int>();
foreach (var move in emptyPositions)
{
BoardState boardForThisMove = board.Clone();
boardForThisMove.SetPiece(move.X, move.Y, piece);
boardStatesForNextMove.Add(boardForThisMove);
Piece nextPiece = piece == Piece.X ? Piece.O : Piece.X;
scores.Add(DoMove(nextPiece, boardForThisMove));
}
int max = scores.Max();
int maxIndex = scores.IndexOf(max);
int min = scores.Min();
int minIndex = scores.IndexOf(min);
if (piece == Piece.X)
{
var selectedMove = emptyPositions[maxIndex];
board.SetPiece(selectedMove.X, selectedMove.Y, piece);
return max;
}
else
{
var selectedMove = emptyPositions[minIndex];
board.SetPiece(selectedMove.X, selectedMove.Y, piece);
return min;
}
}
}
public int DoMove(Piece piece, BoardState boardState)
{
GetUserInput();
do
{
if (IsFinished())
{
return(-100);
}
if (IsInputValid() && boardState.GetPiece(MoveCoordinatesX, MoveCoordinatesY) == Piece.Empty)
{
boardState.SetPiece(MoveCoordinatesX, MoveCoordinatesY, piece);
return(0);
}
GetUserInput();
}while (true);
}
public int DoMove(Piece piece, BoardState boardState)
{
GetUserInput();
do
{
if (IsFinished())
{
return -100;
}
if (IsInputValid() && boardState.GetPiece(MoveCoordinatesX, MoveCoordinatesY) == Piece.Empty)
{
boardState.SetPiece(MoveCoordinatesX, MoveCoordinatesY, piece);
return 0;
}
GetUserInput();
}
while (true);
}
public void WhenXHasNot3XInRow_ThenXDoesNotWin()
{
BoardState target = new BoardState(null);
target.SetPiece(0, 0, Piece.X);
target.SetPiece(1, 1, Piece.X);
target.SetPiece(2, 1, Piece.X);
bool isXWinner = target.IsWinner(Piece.X);
Assert.AreEqual(false, isXWinner);
}
public void WhenXHas3XInRow_ThenXWins()
{
BoardState target = new BoardState(null);
target.SetPiece(0, 1, Piece.X);
target.SetPiece(1, 1, Piece.X);
target.SetPiece(2, 1, Piece.X);
bool isXWinner = target.IsWinner(Piece.X);
Assert.AreEqual(true, isXWinner);
}
public void WhenSettingYIntoField_ThenThatFieldIsOccupiedByY()
{
BoardState target = new BoardState(null);
target.SetPiece(1, 2, Piece.O);
Assert.AreEqual(Piece.O, target.Board[1, 2]);
}
public void WhenSettingXIntoField_ThenThatFieldIsOccupiedByX()
{
BoardState target = new BoardState(null);
target.SetPiece(0, 0, Piece.X);
Assert.AreEqual(Piece.X, target.Board[0, 0]);
}
