using System;

using System.Collections.Generic;

using System.Threading;

using System.Linq;

public class Program

{

    public class Chunk{

        public string Key{get;set;}

        public string Data{get;set;}

        public override string ToString(){

            return "chunkdata : " + Key;    

        }

    }

    public class Loader{

        public Loader(int demoSize){

            //generieren von demo daten

            chunks = 

                Enumerable.Range(0,demoSize)

                .Select(i => new Chunk(){Key=i.ToString(), Data= "data-"+i.ToString()})

                .ToList();

        }

        //das isch indr Databank

        IEnumerable<Chunk> chunks;

        int LoadingSize = 2;

        //Iterator hier

        public IEnumerable<Chunk> GetChunks(){

            int currentBatchSize = 0;

            foreach(var chunk in chunks){

                //expensive load/init operation here

                Thread.Sleep(1000);

                Console.WriteLine("chunk loaded {0} [Time={1}] ", chunk, DateTime.Now.Ticks);

                currentBatchSize++;

                yield return chunk;

            }

        }

    }

    public class ChunkGameObject{

        private Chunk _data;

        public ChunkGameObject(Chunk data){

            _data = data;

            //das ist Teuer

            Thread.Sleep(100);

        }

        public override string ToString(){

            return "gameobject chunk : " + _data;   

        }

    }

    public static void Main()

    {

        var loader = new Loader(20);

        var gameObjects = loader.GetChunks()

            .Select(chunk => new ChunkGameObject(chunk) );

        foreach(var go in gameObjects){

            Console.WriteLine(go);

        }

        var wait10Seconds = Enumerable.Range(0,10)

            .Select(i => {

                Thread.Sleep(1000);

                return i;   

            })

            .ToList();

    }

}