using System;
using System.Collections.Generic;

using OpenTK;

using org.niclasundharald.engine.graphics;

namespace org.niclasundharald.engine
{
	public abstract class WorldObject
	{
		private Matrix4 transformation;
		
		private List<WorldObject>	children;
		
		public WorldObject()
		{
			transformation = Matrix4.Identity;
			children = new List<WorldObject>();
		}

		public virtual Model3D getModel3D(){
			return null;
		}


		public Vector3 Position{
			get { return this.transformation.ExtractTranslation(); }
			set { this.transformation += Matrix4.CreateTranslation(value - this.transformation.ExtractTranslation()); }
		}

		public Matrix4	Transformation {
			get { return this.transformation; }
			set { this.transformation = value; }
		}
		
		public void addChild(WorldObject wo){
			if (!children.Contains(wo)){
				children.Add(wo);
			}
		}

		public void removeChild(WorldObject wo){
			if (children.Contains(wo)){
				children.Remove(wo);
			}
	    }

		public WorldObject[] Children{
			get { return this.children.ToArray(); }
		}
		
	}

	public class ObjectGroup : WorldObject {
		
	}
}