// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
 
//
// Description: Debug-only helper class, dumps TextContainer state to debugger.
//
 
using System;
using System.Diagnostics;
 
namespace System.Windows.Documents
{
#if DEBUG
    // The TextTreeDumper is a helper class, used to dump TextTrees
    // or TextTreeNodes to the debugger.
    //
    // Use it like:
    //
    //  TextTreeDumper.DumpTree(texttree);
    //  TextTreeDumper.DumpNode(someNode);
    //
    internal class TextTreeDumper
    {
        //------------------------------------------------------
        //
        //  Constructors
        //
        //------------------------------------------------------
 
    #region Constructors
 
        // Static class.
        private TextTreeDumper()
        {
        }
 
        #endregion Constructors
 
        //------------------------------------------------------
        //
        //  Internal Methods
        //
        //------------------------------------------------------
 
        #region Internal Methods
 
        // Dumps a TextContainer.
        internal static void Dump(TextContainer tree)
        {
            if (tree.RootNode == null)
            {
                Debug.WriteLine($"<{tree}/>");
            }
            else
            {
                DumpNodeRecursive(tree.RootNode, 0);
            }
        }
 
        // Dumps a TextContainer, xaml style.
        internal static void DumpFlat(TextContainer tree)
        {
            if (tree.RootNode == null)
            {
                Debug.WriteLine($"<{tree}/>");
            }
            else
            {
                DumpFlat(tree.RootNode);
            }
        }
 
        // Dumps a node and all its children.
        internal static void Dump(TextTreeNode node)
        {
            DumpNodeRecursive(node, 0);
        }
 
        // Dumps a node and all contained nodes "flat" -- in notation similar to xaml.
        internal static void DumpFlat(TextTreeNode node)
        {
            Debug.Write($"<{GetFlatPrefix(node)}{node.DebugId}");
 
            if (node.ContainedNode != null)
            {
                Debug.Write(">");
                DumpNodeFlatRecursive(node.GetFirstContainedNode());
                Debug.WriteLine($"</{GetFlatPrefix(node)}{node.DebugId}>");
            }
            else
            {
                Debug.WriteLine("/>");
            }
        }
 
        // Dumps a TextPointer or TextNavigator, including symbol offset.
        internal static void Dump(TextPointer position)
        {
            Debug.WriteLine($"Offset: {position.GetSymbolOffset()} {position}");
        }
 
        #endregion Internal Methods
 
        //------------------------------------------------------
        //
        //  Private Methods
        //
        //------------------------------------------------------
 
        #region Private Methods
 
        // Recursive worker to DumpNode.
        internal static void DumpNodeRecursive(SplayTreeNode node, int depth)
        {
            SplayTreeNode containedNode;
            string indent;
 
            indent = new string(' ', depth*2);
 
            Debug.Write("<");
            Debug.Write(node);
 
            if (node.ContainedNode == null)
            {
                Debug.WriteLine("/>");
            }
            else
            {
                Debug.WriteLine(">");
            }
 
            containedNode = node.ContainedNode;
            if (containedNode != null)
            {
                Debug.Write($"{indent}C ");
                DumpNodeRecursive(containedNode, depth + 1);
            }
 
            if (node.LeftChildNode != null)
            {
                Debug.Write($"{indent}L ");
                DumpNodeRecursive(node.LeftChildNode, depth + 1);
            }
 
            if (node.RightChildNode != null)
            {
                Debug.Write($"{indent}R ");
                DumpNodeRecursive(node.RightChildNode, depth + 1);
            }
 
            if (containedNode != null)
            {
                if (node is TextTreeRootNode)
                {
                    Debug.WriteLine($"{indent}</RootNode>");
                }
                else if (node is TextTreeTextElementNode)
                {
                    Debug.WriteLine($"{indent}</TextElementNode>");
                }
                else
                {
                    Debug.WriteLine($"{indent}</UnknownNode>");
                }
            }
        }
 
        // Dumps a node and all following nodes "flat" -- in notation similar to xaml.
        internal static void DumpNodeFlatRecursive(SplayTreeNode node)
        {
            for (; node != null; node = node.GetNextNode())
            {
                Debug.Write($"<{GetFlatPrefix(node)}{node.DebugId}");
 
                if (node.ContainedNode != null)
                {
                    Debug.Write(">");
                    DumpNodeFlatRecursive(node.GetFirstContainedNode());
                    Debug.Write($"</{GetFlatPrefix(node)}{node.DebugId}>");
                }
                else
                {
                    Debug.Write("/>");
                }
            }
 
        }
 
        // Returns a string identifying the type of a given node.
        private static string GetFlatPrefix(SplayTreeNode node)
        {
            string prefix;
 
            if (node is TextTreeTextNode)
            {
                prefix = "t";
            }
            else if (node is TextTreeObjectNode)
            {
                prefix = "o";
            }
            else if (node is TextTreeTextElementNode)
            {
                prefix = "e";
            }
            else if (node is TextTreeRootNode)
            {
                prefix = "r";
            }
            else
            {
                prefix = "?";
            }
 
            return prefix;
        }
 
        #endregion Private Methods
    }
#endif // DEBUG
}