88 lines
2.2 KiB
C#
88 lines
2.2 KiB
C#
// Copyright (c) AlphaSierraPapa for the SharpDevelop Team (for details please see \doc\copyright.txt)
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// This code is distributed under the GNU LGPL (for details please see \doc\license.txt)
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using System;
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namespace ICSharpCode.AvalonEdit.Document
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{
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/// <summary>
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/// A TextAnchorNode is placed in the TextAnchorTree.
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/// It describes a section of text with a text anchor at the end of the section.
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/// A weak reference is used to refer to the TextAnchor. (to save memory, we derive from WeakReference instead of referencing it)
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/// </summary>
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sealed class TextAnchorNode : WeakReference
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{
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internal TextAnchorNode left, right, parent;
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internal bool color;
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internal int length;
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internal int totalLength; // totalLength = length + left.totalLength + right.totalLength
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public TextAnchorNode(TextAnchor anchor) : base(anchor)
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{
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}
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internal TextAnchorNode LeftMost {
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get {
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TextAnchorNode node = this;
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while (node.left != null)
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node = node.left;
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return node;
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}
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}
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internal TextAnchorNode RightMost {
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get {
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TextAnchorNode node = this;
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while (node.right != null)
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node = node.right;
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return node;
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}
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}
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/// <summary>
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/// Gets the inorder successor of the node.
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/// </summary>
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internal TextAnchorNode Successor {
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get {
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if (right != null) {
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return right.LeftMost;
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} else {
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TextAnchorNode node = this;
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TextAnchorNode oldNode;
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do {
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oldNode = node;
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node = node.parent;
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// go up until we are coming out of a left subtree
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} while (node != null && node.right == oldNode);
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return node;
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}
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}
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}
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/// <summary>
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/// Gets the inorder predecessor of the node.
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/// </summary>
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internal TextAnchorNode Predecessor {
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get {
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if (left != null) {
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return left.RightMost;
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} else {
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TextAnchorNode node = this;
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TextAnchorNode oldNode;
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do {
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oldNode = node;
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node = node.parent;
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// go up until we are coming out of a right subtree
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} while (node != null && node.left == oldNode);
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return node;
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}
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}
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}
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public override string ToString()
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{
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return "[TextAnchorNode Length=" + length + " TotalLength=" + totalLength + " Target=" + Target + "]";
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}
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}
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}
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