#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2015 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.Analysis;
using HeuristicLab.Common;
using HeuristicLab.Core;
using HeuristicLab.Data;
using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding;
using HeuristicLab.EvolutionTracking;
using HeuristicLab.Optimization;
using HeuristicLab.Parameters;
using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;

namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Tracking.Analyzers {
  [Item("SymbolicDataAnalysisTraceOverlapAnalyzer", "An analyzer for trace graph overlap.")]
  [StorableClass]
  public class SymbolicDataAnalysisTraceOverlapAnalyzer : EvolutionTrackingAnalyzer<ISymbolicExpressionTree> {
    private const string PercentageOfBestSolutionsParameterName = "PercentageOfBestSolutions";

    #region parameters
    public IFixedValueParameter<DoubleValue> PercentageOfBestSolutionsParameter {
      get { return (IFixedValueParameter<DoubleValue>)Parameters[PercentageOfBestSolutionsParameterName]; }
    }
    #endregion

    public SymbolicDataAnalysisTraceOverlapAnalyzer() {
      UpdateCounterParameter.ActualName = "TraceOverlapAnalyzerUpdateCounter";
      Parameters.Add(new FixedValueParameter<DoubleValue>(PercentageOfBestSolutionsParameterName, new DoubleValue(1.0)));
    }

    private SymbolicDataAnalysisTraceOverlapAnalyzer(SymbolicDataAnalysisTraceOverlapAnalyzer original, Cloner cloner)
      : base(original, cloner) {
    }

    public override IDeepCloneable Clone(Cloner cloner) {
      return new SymbolicDataAnalysisTraceOverlapAnalyzer(this, cloner);
    }

    [StorableConstructor]
    private SymbolicDataAnalysisTraceOverlapAnalyzer(bool deserializing) : base(deserializing) { }

    public override IOperation Apply() {
      int updateInterval = UpdateIntervalParameter.Value.Value;
      IntValue updateCounter = UpdateCounterParameter.ActualValue;
      // if counter does not yet exist then initialize it with update interval
      // to make sure the solutions are analyzed on the first application of this operator
      if (updateCounter == null) {
        updateCounter = new IntValue(updateInterval);
        UpdateCounterParameter.ActualValue = updateCounter;
      }
      //analyze solutions only every 'updateInterval' times
      if (updateCounter.Value != updateInterval) {
        updateCounter.Value++;
        return base.Apply();
      }
      updateCounter.Value = 1;

      if (PopulationGraph == null)
        return base.Apply();

      var bestSolutionsPercentage = PercentageOfBestSolutionsParameter.Value.Value;
      int n = (int)Math.Round(bestSolutionsPercentage * PopulationSize.Value);
      double avgTraceOverlap = 0;

      if (Generation.Value > 0) {
        var nodes = PopulationGraph.GetByRank(Generation.Value).Cast<IGenealogyGraphNode<ISymbolicExpressionTree>>().OrderByDescending(x => x.Quality).Take(n);
        avgTraceOverlap = nodes.Average(x => TraceCalculator.TraceSubtree(x, 2).Vertices.Count());
      }

      DataTable table;
      if (!Results.ContainsKey("AverageTraceOverlap")) {
        table = new DataTable("Average trace overlap");
        var row = new DataRow("Average trace overlap") { VisualProperties = { StartIndexZero = true } };
        row.Values.Add(avgTraceOverlap);
        table.Rows.Add(row);
        Results.Add(new Result("AverageTraceOverlap", table));
      } else {
        table = (DataTable)Results["AverageTraceOverlap"].Value;
        table.Rows["Average trace overlap"].Values.Add(avgTraceOverlap);
      }
      return base.Apply();
    }
  }
}