source: branches/thasling/DistributedGA/DistributedGA.Core/Implementation/WcfPeerListManager.cs @ 13541

using System;
using System.Collections.Generic;
using System.Configuration;
using System.Linq;
using System.ServiceModel;
using DistributedGA.Core.Domain;
using DistributedGA.Core.Interface;

namespace DistributedGA.Core.Implementation {
  public class WcfPeerListManager : IPeerListManager {
    private string serverString = null;

    private IContactService client = null;

    private PeerInfo myself = null;

    List<PeerInfo> allPeers = null;
    List<PeerInfo> peersForMessaging = null;

    public void Init(PeerInfo source) {
      serverString = ConfigurationManager.AppSettings["ContactServerURL"];
      client = CreateClient();
      myself = source;
      client.RegisterPeer(source);
    }

    public List<PeerInfo> GetPeerList() {
      //TODO: maybe always request a new list from the contact server so that he can refresh the heartbeat...
      if (allPeers == null) {
        allPeers = client.GetPeerList(myself);
        peersForMessaging = ChoosePeersForMessaging(allPeers);
      }
      //return peersForMessaging;
      return allPeers; //TODO: Enable 10% list communication
    }

    public void SendLogToServer(string msg) {
      client.MakeLog(myself, msg);
    }

    private IContactService CreateClient() {
      var binding = new BasicHttpBinding();
      var endpoint = new EndpointAddress(serverString);
      var myChannelFactory = new ChannelFactory<IContactService>(binding, endpoint);

      IContactService client = null;
      client = myChannelFactory.CreateChannel();
      return client;
    }

    private List<PeerInfo> ChoosePeersForMessaging(List<PeerInfo> allPeers) {
      //communicate with 10% of the network
      int noOfPeers = allPeers.Count / 10;
      List<int> indexList = GetRandomItemIndexes(noOfPeers, 0, allPeers.Count - 1);
      List<PeerInfo> res = new List<PeerInfo>();
      foreach (int index in indexList) {
        res.Add(allPeers.ElementAt(index));
      }
      return allPeers;
    }

    private List<int> GetRandomItemIndexes(int noOfItems, int minValue, int maxValue) {
      List<int> res = new List<int>();
      Random rnd = new Random();
      int tmp = -1;
      while (res.Count < noOfItems) {
        tmp = rnd.Next(minValue, maxValue);
        if (!res.Contains(tmp)) {
          res.Add(tmp);
        }
      }
      return res;
    }

  }
}