private void CutLink(PatriciaTree.Node node)
{
if (node == null)
{
throw new ArgumentNullException(nameof(node));
}
if (!(node is PatriciaTree.Leaf))
{
throw new Exception();
}
if (node == this._root)
{
this._root = (PatriciaTree.Node)null;
}
else
{
PatriciaTree.Node node1 = node == node.Parent.Left ? node.Parent.Right : node.Parent.Left;
if (node.Parent == this._root)
{
node1.Parent = (PatriciaTree.Node)null;
this._root = node1;
}
else if (node.Parent == node.Parent.Parent.Left)
{
node.Parent.Parent.Left = node1;
}
else
{
node.Parent.Parent.Right = node1;
}
}
}
private void Branch(PatriciaTree.Node node, PatriciaTree.Node newNode, int bit)
{
if (PatriciaTree.BitHelper.GetBit(node.Key, bit) == PatriciaTree.BitHelper.GetBit(newNode.Key, bit))
{
throw new ArgumentException("node or newNode");
}
PatriciaTree.Node node1 = (PatriciaTree.Node) new PatriciaTree.BranchNode(this._nodes.Count, this.GetBranchKey(node, newNode, bit), bit);
this._nodes.Add((PatriciaTree.INode)node1);
if (node.Parent != null)
{
if (node.Parent.Left == node)
{
node.Parent.Left = node1;
}
else
{
node.Parent.Right = node1;
}
}
else
{
this._root = node1;
}
if (node.Bit > bit && PatriciaTree.BitHelper.GetBit(node.Key, bit))
{
node1.Left = newNode;
node1.Right = node;
}
else
{
node1.Left = node;
node1.Right = newNode;
}
}
public bool Remove(string key)
{
PatriciaTree.Node node = this.FindNode(key);
if (node == null)
{
return(false);
}
this.CutLink(node);
this._nodes.Remove((PatriciaTree.INode)node);
this._items.Remove(key);
return(true);
}
private PatriciaTree.Node FindNode(PatriciaTree.Node node, string key)
{
if (node == null)
{
return((PatriciaTree.Node)null);
}
if (!(node is PatriciaTree.Leaf))
{
return(this.FindNode(PatriciaTree.BitHelper.GetBit(key, node.Bit) ? node.Right : node.Left, key));
}
if (!(node.Key == key))
{
return((PatriciaTree.Node)null);
}
return(node);
}
private void AddNode(PatriciaTree.Node node, IPatriciaTreeItem item)
{
if (node == null)
{
this._root = (PatriciaTree.Node) new PatriciaTree.Leaf(this._nodes.Count, item);
this._nodes.Add((PatriciaTree.INode) this._root);
}
else
{
int start = node.Parent == null ? 0 : node.Parent.Bit;
if (node is PatriciaTree.BranchNode)
{
int bit = PatriciaTree.BitHelper.CompareBit(node.Key, item.Key, start, node.Bit);
if (0 <= bit)
{
PatriciaTree.Leaf leaf = new PatriciaTree.Leaf(this._nodes.Count, item);
this._nodes.Add((PatriciaTree.INode)leaf);
this.Branch(node, (PatriciaTree.Node)leaf, bit);
}
else
{
this.AddNode(PatriciaTree.BitHelper.GetBit(item.Key, node.Bit) ? node.Right : node.Left, item);
}
}
else
{
if (!(node is PatriciaTree.Leaf))
{
throw new Exception("invalid node type.");
}
int bit = PatriciaTree.BitHelper.CompareBit(node.Key, item.Key, start);
if (0 >= bit)
{
throw new ArgumentException(nameof(item));
}
PatriciaTree.Leaf leaf = new PatriciaTree.Leaf(this._nodes.Count, item);
this._nodes.Add((PatriciaTree.INode)leaf);
this.Branch(node, (PatriciaTree.Node)leaf, bit);
}
}
}
private string GetBranchKey(PatriciaTree.Node node1, PatriciaTree.Node node2, int bit)
{
return(PatriciaTree.BitHelper.SubString(PatriciaTree.BitHelper.GetBitCount(node1.Key) <= bit ? node2.Key : node1.Key, bit));
}