// public jcMove Query
// Querying the table for a ready-made move to play. Return null if there
// is none
public jcMove Query(jcBoard theBoard)
{
// First, look for a match in the table
int key = Math.Abs(theBoard.HashKey() % TABLE_SIZE);
int hashLock = theBoard.HashLock();
// If the hash lock doesn't match the one for our position, get out
if (Table[key].theLock != hashLock)
return null;
// If there is an entry for this board in the table, verify that it
// contains a move for the current side
if (theBoard.GetCurrentPlayer() == jcPlayer.SIDE_BLACK)
{
if (Table[key].BlackMove.MoveType != jcOpeningBookEntry.NO_MOVE)
return Table[key].BlackMove;
}
else
{
if (Table[key].WhiteMove.MoveType != jcOpeningBookEntry.NO_MOVE)
return Table[key].WhiteMove;
}
// If we haven't found anything useful, quit
return null;
}
private bool StoreMove(jcBoard theBoard, jcMove theMove)
{
// Where should we store this data?
int key = Math.Abs(theBoard.HashKey() % TABLE_SIZE);
int hashLock = theBoard.HashLock();
// Is there already an entry for a different board position where we
// want to put this? If so, mark it deleted
if (Table[key].theLock != hashLock)
{
Table[key].BlackMove.MoveType = jcOpeningBookEntry.NO_MOVE;
Table[key].WhiteMove.MoveType = jcOpeningBookEntry.NO_MOVE;
}
// And store the new move
Table[key].theLock = hashLock;
if (theBoard.GetCurrentPlayer() == jcPlayer.SIDE_BLACK)
{
Table[key].BlackMove.Copy(theMove);
}
else
{
Table[key].WhiteMove.Copy(theMove);
}
return true;
}
