#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2014 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.Linq;
using HeuristicLab.Core;
using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding;
using HeuristicLab.EvolutionTracking;

namespace HeuristicLab.Problems.DataAnalysis.Symbolic {
  public class SymbolicDataAnalysisExpressionBeforeCrossoverOperator : BeforeCrossoverOperator<ISymbolicExpressionTree> {
    public override IOperation Apply() {
      var result = base.Apply(); // the child will be added to the graph before the crossover
      var parents = ParentsParameter.ActualValue.ToList();
      var childVertex = (IGenealogyGraphNode<ISymbolicExpressionTree>)GenealogyGraph[parents[0]].Last(); // use the parent since it is actually the child before crossover (and the ChildParameter doesn't have a value yet)
      var arcs = childVertex.InArcs.ToList();

      for (int i = 0; i < parents.Count; ++i) {
        var nodes = parents[i].IterateNodesPrefix().ToList();
        arcs[i].Data = nodes;
      }
      var parentVertices = childVertex.InArcs.Select(x => (IGenealogyGraphNode<ISymbolicExpressionTree>)x.Source).ToList();
      if (parents[0].Length != parentVertices[0].Content.Length || parents[1].Length != parentVertices[1].Content.Length) {
        throw new Exception("Inconsistency detected in GenealogyGraph.");
      }

      return result;
    }
  }
}