Sketch for Entitas-CSharp Behaviour Tree implementation

Entitas-BT.cs

// Based on http://www.gamasutra.com/blogs/ChrisSimpson/20140717/221339/Behavior_trees_for_AI_How_they_work.php

public enum NodeStatus 
{
    Success, Failure, Running
}

public interface IBehaviorNode
{
    NodeStatus Execute(Entity entity); 
}

public sealed class Sequence : IBehaviorNode
{
    private IBehaviorNode[] nodes;
    public Sequence(params IBehaviorNode[] nodes) 
    {
        this.nodes = nodes;
    }

    public NodeStatus Execute(Entity entity)
    {
        var result = NodeStatus.Success;
        for (int i = 0; i < nodes.Length; i++)
        {
            result = nodes[i].Execute(entity);
            if (result == NodeStatus.Running || result == NodeStatus.Failure){
                return result;
            } 
        }
        return result;
    }
}

public sealed class Selector : IBehaviorNode
{
    private IBehaviorNode[] nodes;
    public Selector(params IBehaviorNode[] nodes) 
    {
        this.nodes = nodes;
    }

    public NodeStatus Execute(Entity entity)
    {
        var result = NodeStatus.Success;
        for (int i = 0; i < nodes.Length; i++)
        {
            result = nodes[i].Execute(entity);
            if (result == NodeStatus.Running || result == NodeStatus.Success){
                return result;
            } 
        }
        return result;
    }
}