using System.Collections.Concurrent;

public class TreeNode
{
    public int ID { get; set; }
    public int sInx { get; set; }
    public TreeNode parent { get; set; }
    public List<TreeNode> children = new List<TreeNode>();
    
    public TreeNode(int ID){this.ID = ID;}
}

ConcurrentDictionary<int, TreeNode> lookup = new ConcurrentDictionary<int, TreeNode>();
ConcurrentDictionary<int, TreeNode> rootNodes = new ConcurrentDictionary<int, TreeNode>();

public void simulationStart()
{
    lookup.Clear();
    rootNodes.Clear();
    tf.SetThreaded(true);
    tf.SetThreadedIterations(1);
}
public void simulationStep()
{    
}
public void simulationStepThreaded(int startInx, int endInx, int threadInx)                    
{
    if (tf.GetThreadedIteration() == 0)
    {
        for (int i = startInx; i < endInx; i++)
        {
            int sInx = tf.GetSimIndex(i);
            if (tf.GetEventAge(sInx) == 0)
            {
            
                //// convert flat list of Ids/parentIds refs to nested tree structure ////
            
                int ID = tf.GetID(sInx);
                int parentID = tf.GetParentID(sInx);

                // add node to lookup or get from if already found as a parent
                TreeNode iNode = new TreeNode(ID);
                iNode = lookup.GetOrAdd(ID, iNode);
                // register simulation Index
                iNode.sInx = sInx;
                // check for valid parent
                if (parentID < 0)
                {   // is a root node
                    rootNodes.TryAdd(ID, iNode);
                }
                else
                {   // is a child node - add or get parent node to/from lookup
                    TreeNode parentNode = new TreeNode(parentID);
                    parentNode = lookup.GetOrAdd(parentID, parentNode);
                    // add node to parent children list
                    parentNode.children.Add(iNode);
                    // update parent property
                    iNode.parent = parentNode;
                }
            }
        }
    }
    
    if (tf.GetThreadedIteration() == 1)
    {
        for (int i = startInx; i < endInx; i++)
        {
            int sInx = tf.GetSimIndex(i);
            if (tf.GetEventAge(sInx) == 0)
            {
                TreeNode value;
                //rootNodes.TryGetValue(tf.GetID(sInx),out value);
                lookup.TryGetValue(tf.GetID(sInx),out value);
                Print((value.parent!=null)? value.parent.ID : -1);            
            }
        }

    }
}