private void MoveInternal(int from, int to)
{
var color = CurrentColor.Value;
Checker checker = null;
// bear off
if (to == OFFBOARD)
{
var rollNumber = color == CheckerColor.White ? 24 - from : from + 1;
// roll number can be higher for bear off, use highest roll number
if (!remainingRollNumbers.Contains(rollNumber))
{
if (remainingRollNumbers.Count == 1 ||
remainingRollNumbers[0] >= remainingRollNumbers[1])
{
rollNumber = remainingRollNumbers[0];
}
else
{
rollNumber = remainingRollNumbers[1];
}
}
remainingRollNumbers.Remove(rollNumber);
checker = board[from].Checkers.Pop();
offBoard.Add(checker);
checker.Position = OFFBOARD;
var countOnBoard = GetCheckers().Count((c) => c.Position >= 0 && c.Position <= 23);
if (countOnBoard == 0)
{
SetWinner(color);
}
}
// remove from bar or move in board
else
{
// remove from bar
if (from == BAR)
{
remainingRollNumbers.Remove(color == CheckerColor.White ? to + 1 : 24 - to);
checker = bar.Find((c) => c.Color == color);
bar.Remove(checker);
}
// move in board
else
{
remainingRollNumbers.Remove(Math.Abs(from - to));
checker = board[from].Checkers.Pop();
}
var toPoint = board[to];
if (toPoint.Checkers.Any() && toPoint.Checkers.Peek().Color != color)
{
// blot is hit
var hitChecker = toPoint.Checkers.Pop();
hitChecker.Position = BAR;
bar.Add(hitChecker);
}
toPoint.Checkers.Push(checker);
checker.Position = to;
}
if (!GameOver && remainingRollNumbers.Count == 0)
{
CurrentColor = color == CheckerColor.White ? CheckerColor.Black : CheckerColor.White;
LastRoll = CurrentRoll;
CurrentRoll = null;
}
}
public Checker(Checker c)
{
Id = c.Id;
Color = c.Color;
Position = c.Position;
}