#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2013 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 HeuristicLab.Common;
using HeuristicLab.Core;
using HeuristicLab.Encodings.PermutationEncoding;
using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;

namespace HeuristicLab.Analysis.SolutionCaching.PermutationEncoding {
  [Item("PermutationSolutionInformation", "Displays information about a real vector solution.")]
  [StorableClass]
  public class PermutationSolutionInformation : SolutionInformation<Encodings.PermutationEncoding.Permutation> {
    public PermutationSolutionInformation() : base() { }
    [StorableConstructor]
    protected PermutationSolutionInformation(bool deserializing) : base(deserializing) { }

    protected PermutationSolutionInformation(PermutationSolutionInformation original, Cloner cloner)
      : base(original, cloner) {
    }
    public override IDeepCloneable Clone(Cloner cloner) {
      return new PermutationSolutionInformation(this, cloner);
    }

    public override int GetHashCode() {
      //use rotating hash, should be enough
      //see: http://eternallyconfuzzled.com/tuts/algorithms/jsw_tut_hashing.aspx
      var pweq = new PermutationEqualityComparer();
      int h = 0;

      h = (h << 4) ^ (h >> 28) ^ ProducedBy.GetHashCode();
      h = (h << 4) ^ (h >> 28) ^ Iteration.GetHashCode();

      if (Predecessors != null) {
        foreach (var parent in Predecessors) {
          h = (h << 4) ^ (h >> 28) ^ pweq.GetHashCode(parent);
        }
      }
      return h;
    }
  }
}