public bool LayoutNextPiece(RotatedPiece rotatedPiece)
{
int firstEmptyX;
int firstEmptyY;
var foundAnEmptySquare = FindFirstEmptySquare(out firstEmptyX, out firstEmptyY);
if (!foundAnEmptySquare)
throw new InvalidOperationException("The puzzle is already solved!");
return PlacePieceAt(rotatedPiece, firstEmptyX, firstEmptyY);
}
private IList<bool> BuildDataItem(int pieceIndex, RotatedPiece rotatedPiece, int x, int y)
{
var numColumns = _pieces.Length + _board.BoardSize * _board.BoardSize;
var dataItem = new bool[numColumns];
dataItem[pieceIndex] = true;
var w = rotatedPiece.Width;
var h = rotatedPiece.Height;
for (var pieceX = 0; pieceX < w; pieceX++)
{
for (var pieceY = 0; pieceY < h; pieceY++)
{
if (rotatedPiece.SquareAt(pieceX, pieceY) == null) continue;
var boardX = x + pieceX;
var boardY = y + pieceY;
var boardLocationColumnIndex = _pieces.Length + (_board.BoardSize * boardX) + boardY;
dataItem[boardLocationColumnIndex] = true;
}
}
return dataItem;
}
private void AddDataItemsForPieceWithSpecificOrientation(IList<IList<bool>> data, int pieceIndex, Piece piece, Orientation orientation)
{
var rotatedPiece = new RotatedPiece(piece, orientation);
for (var x = 0; x < _board.BoardSize; x++)
{
for (var y = 0; y < _board.BoardSize; y++)
{
_board.Reset();
_board.ForceColourOfSquareZeroZeroToBeBlack();
if (!_board.PlacePieceAt(rotatedPiece, x, y)) continue;
var dataItem = BuildDataItem(pieceIndex, rotatedPiece, x, y);
data.Add(dataItem);
_dictionary.Add(data.Count - 1, Tuple.Create(rotatedPiece, x, y));
}
}
}
public bool PlacePieceAt(RotatedPiece rotatedPiece, int x, int y)
{
if (x < 0 || x >= BoardSize) throw new ArgumentOutOfRangeException("x");
if (y < 0 || y >= BoardSize) throw new ArgumentOutOfRangeException("y");
if (x + rotatedPiece.Width > BoardSize) return false;
if (y + rotatedPiece.Height > BoardSize) return false;
// Check for any overlap with existing pieces before setting any squares.
for (var pieceX = 0; pieceX < rotatedPiece.Width; pieceX++) {
for (var pieceY = 0; pieceY < rotatedPiece.Height; pieceY++) {
var square = rotatedPiece.SquareAt(pieceX, pieceY);
if (square != null) {
if (_pieces[x + pieceX, y + pieceY] != null)
return false;
}
}
}
if (ColourOfSquareZeroZero.HasValue) {
var colourOfSquareZeroZero = ColourOfSquareZeroZero.Value;
// Check that each square of the piece to be placed has
// the appropriate colour for its intended board position.
for (var pieceX = 0; pieceX < rotatedPiece.Width; pieceX++) {
for (var pieceY = 0; pieceY < rotatedPiece.Height; pieceY++) {
var square = rotatedPiece.SquareAt(pieceX, pieceY);
if (square != null) {
var boardX = x + pieceX;
var boardY = y + pieceY;
var expectedColour = colourOfSquareZeroZero.RelativeColour(boardX, boardY);
if (square.Colour != expectedColour)
return false;
}
}
}
}
Square firstSquare = null;
// It's now OK to go ahead and set the squares for the new piece.
for (var pieceX = 0; pieceX < rotatedPiece.Width; pieceX++) {
for (var pieceY = 0; pieceY < rotatedPiece.Height; pieceY++) {
var square = rotatedPiece.SquareAt(pieceX, pieceY);
if (square != null) {
// Remember the first square in case we haven't set _colourOfSquareZeroZero yet.
if (firstSquare == null)
firstSquare = square;
_pieces[x + pieceX, y + pieceY] = new PieceHolder { RotatedPiece = rotatedPiece, Square = square };
}
}
}
if (!ColourOfSquareZeroZero.HasValue && firstSquare != null) {
var boardX = x + firstSquare.X;
var boardY = y + firstSquare.Y;
ColourOfSquareZeroZero = firstSquare.Colour.RelativeColour(boardX, boardY);
}
return true;
}
private static void PrintRotatedPiece(RotatedPiece rotatedPiece)
{
string orientationInitialLetter = rotatedPiece.Orientation.ToString().Substring(0, 1);
Console.Write("{0}{1} ", rotatedPiece.Piece.Name, orientationInitialLetter);
}