#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2011 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
 *
 * This file is part of HeuristicLab.
 *
 * HeuristicLab is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * HeuristicLab is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
 */
#endregion

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using HeuristicLab.Core;
using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
using HeuristicLab.Common;
using HeuristicLab.Optimization;

namespace HeuristicLab.Operators.MPISupport {
  [Item("MPIUnidirectionalRingMigrator", "A unidirectional ring migrator that utilizes MPI if available.")]
  [StorableClass]
  public class MPIUnidirectionalRingMigrator : SingleSuccessorOperator {
    [StorableConstructor]
    private MPIUnidirectionalRingMigrator(bool deserializing) : base(deserializing) { }
    private MPIUnidirectionalRingMigrator(MPIUnidirectionalRingMigrator original, Cloner cloner) : base(original, cloner) { }
    public override IDeepCloneable Clone(Cloner cloner) {
      return new MPIUnidirectionalRingMigrator(this, cloner);
    }
    public MPIUnidirectionalRingMigrator()
      : base() {
    }

    public static int Channel = 100;

    public override IOperation Apply() {
      if (MPI.Communicator.world != null) {
        int size = MPI.Communicator.world.Size;
        if (size > 1) {
          int i = MPI.Communicator.world.Rank;
          IScope scope = ExecutionContext.Scope;

          IScope emigrants = scope.SubScopes[1];
          scope.SubScopes.Remove(emigrants);
          int recipent = i + 1;
          if (recipent == size)
            recipent = 0;

          Console.WriteLine("MIGRATE " + i + " TO " + recipent);
          MPI.Communicator.world.Send<MPITransportWrapper<IScope>>(
            new MPITransportWrapper<IScope>(emigrants), recipent, Channel);

          IScope immigrants = null;
          int sender = i - 1;
          if (sender < 0)
            sender = size - 1;

          Console.WriteLine("MIGRATE " + i + " FROM " + sender);
          immigrants = MPI.Communicator.world.Receive<MPITransportWrapper<IScope>>(sender, Channel).InnerItem;

          scope.SubScopes.Add(immigrants);
        }
      }

      return base.Apply();
    }
  }
}