public bool IsViable(Move move)
{
int from = move.From;
int fromRow = move.FromRow;
int to = move.To;
int toRow = move.ToRow;
Pile fromPile = FindTableau[from];
Pile toPile = FindTableau[to];
if (toPile.Count == 0)
{
if (fromPile.Count == 0 && FindTableau.GetDownCount(from) == 0)
{
return(false);
}
else if (fromRow != 0 && fromPile[fromRow - 1].IsTargetFor(fromPile[fromRow]))
{
return(false);
}
return(true);
}
bool isSwap = move.Type == MoveType.Swap;
Card fromParent = fromRow != 0 ? fromPile[fromRow - 1] : Card.Empty;
Card fromChild = fromPile[fromRow];
Card toParent = toRow != 0 ? toPile[toRow - 1] : Card.Empty;
Card toChild = toRow != toPile.Count ? toPile[toRow] : Card.Empty;
int oldOrderFrom = GetOrder(fromParent, fromChild);
int newOrderFrom = GetOrder(toParent, fromChild);
int oldOrderTo = isSwap ? GetOrder(toParent, toChild) : 0;
int newOrderTo = isSwap ? GetOrder(fromParent, toChild) : 0;
int order = newOrderFrom - oldOrderFrom + newOrderTo - oldOrderTo;
if (order < 0)
{
return(false);
}
int netRunLengthFrom = RunFinder.GetNetRunLength(newOrderFrom, from, fromRow, to, toRow);
int netRunLengthTo = isSwap ? RunFinder.GetNetRunLength(newOrderTo, to, toRow, from, fromRow) : 0;
int netRunLength = netRunLengthFrom + netRunLengthTo;
if (order == 0 && netRunLength < 0)
{
return(false);
}
int delta = 0;
if (order == 0 && netRunLength == 0)
{
if (!isSwap && oldOrderFrom == 1 && newOrderFrom == 1)
{
delta = RunFinder.GetRunDelta(from, fromRow, to, toRow);
}
if (delta <= 0)
{
return(false);
}
}
return(true);
}