public Coordinates Traceback(Coordinates coordinates)
{
if (coordinates.X > 0 || coordinates.Y > 0)
{
if (coordinates.Y == 0) // must be horizontal as we are on the top row
{
TracebackPath.Add(Move.HorizontalMove);
return(Traceback(HorizontalMoveCoordinates(coordinates.X, coordinates.Y)));
}
if (coordinates.X == 0) // must be vertical as we are on left most column
{
TracebackPath.Add(Move.VerticalMove);
return(Traceback(VerticalMoveCoordinates(coordinates.X, coordinates.Y)));
}
var verticalValue = VerticalMoveValue(coordinates.X, coordinates.Y);
var diagonalValue = DiagonalMoveValue(coordinates.X, coordinates.Y);
var horizontalValue = HorizontalMoveValue(coordinates.X, coordinates.Y);
var currentValue = Grid.GetValue(coordinates.X, coordinates.Y);
if (currentValue == diagonalValue)
{
TracebackPath.Add(Move.DiagonalMove);
return(Traceback(DiagonalMoveCoordinates(coordinates.X, coordinates.Y)));
}
//get rid of ones that do not differ by one
verticalValue = FindDifference(verticalValue, currentValue);
diagonalValue = FindDifference(diagonalValue, currentValue);
horizontalValue = FindDifference(horizontalValue, currentValue);
if (diagonalValue >= horizontalValue && diagonalValue >= verticalValue)
{
TracebackPath.Add(Move.DiagonalMove);
return(Traceback(DiagonalMoveCoordinates(coordinates.X, coordinates.Y)));
}
if (verticalValue >= horizontalValue && verticalValue >= diagonalValue)
{
TracebackPath.Add(Move.VerticalMove);
return(Traceback(VerticalMoveCoordinates(coordinates.X, coordinates.Y)));
}
else
{
TracebackPath.Add(Move.HorizontalMove);
return(Traceback(HorizontalMoveCoordinates(coordinates.X, coordinates.Y)));
}
}
return(new Coordinates(0, 0));
}
