private static Board GetNextBoard(Board board)
{
var boardPieces = board.ToIntArray();
var nextPerm = PermutationCalculator<int>.GetNextPermutation(boardPieces);
return nextPerm == null
? null
: new Board(nextPerm.ToArray());
}
public Board ReflectOverYEqualsX(Board board)
{
var newBoard = new Board(board.N);
for (var i = 0; i < board.N; i++)
{
newBoard[board[i]] = i;
}
return newBoard;
}
private static bool AreEqualBoards(Board left, Board right)
{
if (left.N != right.N) return false;
for (var i = 0; i < left.N; i++)
{
if (left[i] != right[i]) return false;
}
return true;
}
public Board ReflectOverXAxis(Board board)
{
var newBoard = new Board(board.N);
var maxIndex = board.N - 1;
for (var i = 0; i < board.N; i++)
{
newBoard[i] = maxIndex - board[i];
}
return newBoard;
}
public Board ReflectOverYEqualsMinusX(Board board)
{
var newBoard = new Board(board.N);
var maxIndex = board.N - 1;
for (var i = 0; i < board.N; i++)
{
var oldX = i;
var oldY = board[i];
var newX = maxIndex - oldY;
var newY = maxIndex - oldX;
newBoard[newX] = newY;
}
return newBoard;
}
public Board Rotate180Degrees(Board board)
{
var newBoard = new Board(board.N);
var maxIndex = board.N - 1;
for (var i = 0; i < board.N; i++)
{
var oldX = i;
var oldY = board[i];
var newX = maxIndex - oldX;
var newY = maxIndex - oldY;
newBoard[newX] = newY;
}
return newBoard;
}
public Board ReflectOverYAxis(Board board)
{
var values = board.ToIntArray().Reverse().ToArray();
return new Board(values);
}
private static Board Shuffle(Board board)
{
var shuffler = new ArrayShuffler();
var shuffledBoard = new Board(shuffler.Execute(board.ToIntArray()));
return shuffledBoard;
}
private bool IsUnique(Board board)
{
if (IsAlreadySolution(board)) return false;
var rotator = new BoardTransformer();
var copy = rotator.ReflectOverXAxis(board);
if (IsAlreadySolution(copy)) return false;
copy = rotator.ReflectOverYAxis(board);
if (IsAlreadySolution(copy)) return false;
copy = rotator.ReflectOverYEqualsX(board);
if (IsAlreadySolution(copy)) return false;
copy = rotator.ReflectOverYEqualsMinusX(board);
if (IsAlreadySolution(copy)) return false;
copy = rotator.Rotate90Degrees(board);
if (IsAlreadySolution(copy)) return false;
copy = rotator.Rotate180Degrees(board);
if (IsAlreadySolution(copy)) return false;
copy = rotator.Rotate270Degrees(board);
if (IsAlreadySolution(copy)) return false;
return true;
}
private bool IsAUniqueSolution(Board board)
{
if (!IsASolution(board)) return false;
return IsUnique(board);
}
private bool IsASolution(Board board)
{
var clashChecker = new BoardClashChecker();
if (clashChecker.Execute(board)) return false;
return true;
}
private bool IsAlreadySolution(Board potantialSolution)
{
return _solutions.Any(solution => AreEqualBoards(potantialSolution, solution));
}
private Board InitializeBoard()
{
var board = new Board(N);
for (int i = 0; i < N; i++)
board[i] = i;
return board;
}
