public void SwitchNodes(IAvlNode oldNode, IAvlNode newNode)
{
if (oldNode == newNode)
{
return;
}
var oldBalance = oldNode.Balance;
var newLeft = newNode.Left;
var newRight = newNode.Right;
var oldParent = oldNode.Parent;
oldNode.Balance = newNode.Balance;
newNode.Balance = oldBalance;
// oldNode and newNode are Parent and Child
if (newNode.Parent == oldNode)
{
if (oldNode.Parent != null)
{
if (oldNode.Parent.Right == oldNode)
{
oldNode.Parent.Right = newNode;
}
else
{
oldNode.Parent.Left = newNode;
}
}
else if (oldNode == Root)
{
Root = (T)newNode;
}
newNode.Parent = oldNode.Parent;
oldNode.Parent = newNode;
if (oldNode.Left == newNode)
{
// update Children
newNode.Left = oldNode;
newNode.Right = oldNode.Right;
oldNode.Left = newLeft;
oldNode.Right = newRight;
// update Parents of Children
if (newNode.Right != null)
{
newNode.Right.Parent = newNode;
}
if (oldNode.Right != null)
{
oldNode.Right.Parent = oldNode;
}
if (oldNode.Left != null)
{
oldNode.Left.Parent = oldNode;
}
}
else
{ //odlNode.Right == newNode
// update Children
newNode.Right = oldNode;
newNode.Left = oldNode.Left;
oldNode.Left = newLeft;
oldNode.Right = newRight;
// update Parents of Children
if (newNode.Left != null)
{
newNode.Left.Parent = newNode;
}
if (oldNode.Right != null)
{
oldNode.Right.Parent = oldNode;
}
if (oldNode.Left != null)
{
oldNode.Left.Parent = oldNode;
}
}
return;
}
if (oldNode.Parent == newNode)
{
if (newNode.Parent != null)
{
if (newNode.Parent.Right == newNode)
{
newNode.Parent.Right = oldNode;
}
else
{
newNode.Parent.Left = oldNode;
}
}
else if (newNode == Root)
{
Root = (T)oldNode;
}
oldNode.Parent = newNode.Parent;
newNode.Parent = oldNode;
if (newNode.Left == oldNode)
{
// update Children
newNode.Left = oldNode.Left;
newNode.Right = oldNode.Right;
oldNode.Left = newNode;
oldNode.Right = newRight;
// update Parents of Children
if (newNode.Right != null)
{
newNode.Right.Parent = newNode;
}
if (newNode.Left != null)
{
newNode.Left.Parent = newNode;
}
if (oldNode.Right != null)
{
oldNode.Right.Parent = oldNode;
}
}
else
{
// update Children
newNode.Left = oldNode.Left;
newNode.Right = oldNode.Right;
oldNode.Left = newLeft;
oldNode.Right = newNode;
// update Parents of Children
if (newNode.Right != null)
{
newNode.Right.Parent = newNode;
}
if (newNode.Left != null)
{
newNode.Left.Parent = newNode;
}
if (oldNode.Left != null)
{
oldNode.Left.Parent = oldNode;
}
}
return;
}
// no node is Parent of the other
// update Parents
if (oldNode.AvlGetSibling() == newNode)
{
if (newNode.Parent.Right == newNode)
{
newNode.Parent.Right = oldNode;
newNode.Parent.Left = newNode;
}
else
{
newNode.Parent.Left = oldNode;
newNode.Parent.Right = newNode;
}
}
else
{
oldNode.Parent = newNode.Parent;
if (newNode.Parent != null)
{
if (newNode.Parent.Right == newNode)
{
newNode.Parent.Right = oldNode;
}
else
{
newNode.Parent.Left = oldNode;
}
}
else if (newNode == Root)
{
Root = (T)oldNode;
}
newNode.Parent = oldParent;
if (oldParent != null)
{
if (oldParent.Right == oldNode)
{
oldParent.Right = newNode;
}
else
{
oldParent.Left = newNode;
}
}
else if (oldNode == Root)
{
Root = (T)newNode;
}
}
// assign Children of newNode
newNode.Left = oldNode.Left;
if (newNode.Left != null)
{
newNode.Left.Parent = newNode;
}
newNode.Right = oldNode.Right;
if (newNode.Right != null)
{
newNode.Right.Parent = newNode;
}
// assign Children of oldNode
oldNode.Left = newLeft;
if (oldNode.Left != null)
{
oldNode.Left.Parent = oldNode;
}
oldNode.Right = newRight;
if (oldNode.Right != null)
{
oldNode.Right.Parent = oldNode;
}
}
