TreeAssembler.cs :  » Game » SokoSolve-Sokoban » SokoSolve » Common » Structures » C# / CSharp Open Source

using System;
using System.Collections.Generic;
using System.Text;
using SokoSolve.Common;

namespace SokoSolve.Common.Structures{
  public static class TreeAssembler
  {
    
    /// <summary>
    /// Assemble a tree from ID and REF parent identifiers
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <param name="source"></param>
    /// <param name="GetID"></param>
    /// <param name="GetREF"></param>
    /// <returns></returns>
    public static Tree<T> Create<T>(IEnumerable<T> source, ToString<T> GetID, ToString<T> GetREF)
    {
      Tree<T> result = new Tree<T>();

      Dictionary<string, T> nodelist = new Dictionary<string, T>();

      T root = default(T);
      foreach(T item in source)
      {
        string ID = GetID(item);
        if (ID == null) throw new ArgumentNullException("ID");

        string parentID = GetREF(item);
        if (parentID == null)
        {
          // Parent
          if (root != null) throw new ArgumentException("Cannot have two roots");
          root = item;
        }

        if (nodelist.ContainsKey(ID)) throw new ArgumentException(string.Format("Duplicate Key : {0}", ID));

        nodelist.Add(ID, item);
      }

      result.Root.Data = root;

      AddChildren(result.Root, GetID, GetREF, source);

      return result;
    }

    private static void AddChildren<T>(TreeNode<T> current, ToString<T> GetID, ToString<T> GetREF, IEnumerable<T> source)
    {
      string currentID = GetID(current.Data); 
      foreach(T item in source)
      {
        if(GetREF(item) == currentID) 
        {
          // Found child
          current.Add(item);
        }
      }

            if (current.HasChildren)
            {
                foreach (TreeNode<T> kid in current.Children)
                {
                    AddChildren<T>(kid, GetID, GetREF, source);
                }
            }
    }

    
  }
}