private void _attachToParentEdge(AvlTreeNode <T> node, AvlTreeEdge <T> edge)
{
Debug.Assert(edge.IsChildOrRoot);
// if node != null, node.parent should be free
Debug.Assert((node == null) || (node.Parent == null));
// if edge is child then the target should be free;
Debug.Assert((edge.IsRoot) || (edge.Target() == null));
if (edge.IsRoot)
{
_setAsRoot(node);
}
else if (edge.Direction == AvlTreeNodeDirection.Left)
{
edge.Source.Left = node;
if (node != null)
{
node.Parent = edge.Source;
}
}
else
{
edge.Source.Right = node;
if (node != null)
{
node.Parent = edge.Source;
}
}
}
public static AvlTreeEdge <T> FindFree <T>(this AvlTreeNode <T> source, Func <AvlTreeNode <T>, AvlTreeEdge <T> > selector)
{
if (source == null)
{
return(AvlTreeEdge <T> .Root);
}
var current = source;
AvlTreeEdge <T> res = null;
while (res == null)
{
var edge = selector(current);
var next = edge.Target();
if (next == null)
{
res = edge;
}
current = next;
}
return(res);
}
public bool Equals(AvlTreeEdge <T> other)
{
if (ReferenceEquals(other, null))
{
return(false);
}
return((Source == other.Source) &&
(Direction == other.Direction));
}
internal AvlTreeNode <T> InternalInsertNode(AvlTreeEdge <T> edge, AvlTreeNode <T> newNode)
{
Debug.Assert(edge.IsChildOrRoot);
if (Count == int.MaxValue)
{
throw new InvalidOperationException("Maximum size reached");
}
_version++;
// newnode should be dettached from the tree
Debug.Assert(newNode != null);
Debug.Assert(newNode.Parent == null);
Debug.Assert(newNode.Left == null);
Debug.Assert(newNode.Right == null);
Debug.Assert(newNode._tree == null);
_attachToParentEdge(newNode, edge);
_rebalanceAfterChange(edge.Source);
return(newNode);
}
public static AvlTreeEdge <T> For <T>(AvlTreeNode <T> source, AvlTreeNodeDirection direction)
{
return(AvlTreeEdge <T> .For(source, direction));
}