public void Enqueue(T change)
{
if (_currentGroup == null || !_currentGroup.IsOpenGroup)
{
_currentGroup = CreateNewItemGroup(change);
_itemGroupQueue.Enqueue(_currentGroup);
}
else if (_currentGroup.IsBlocking != change.IsBlocking)
{
_currentGroup.CloseGroup();
_currentGroup = CreateNewItemGroup(change);
_itemGroupQueue.Enqueue(_currentGroup);
}
_currentGroup.Enqueue(change);
}