#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.Linq;
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("SymbolicDataAnalysisSchemaFrequencyAnalyzer", "An analyzer which counts schema frequencies in the population.")]
  [StorableClass]
  public class SymbolicDataAnalysisSchemaFrequencyAnalyzer : EvolutionTrackingAnalyzer<ISymbolicExpressionTree> {
    private const string MinimumSchemaLengthParameterName = "MinimumSchemaLength";

    [Storable]
    private readonly SymbolicExpressionTreePhenotypicSimilarityCalculator phenotypicSimilarityCalculator;

    [Storable]
    private readonly SymbolicExpressionTreeBottomUpSimilarityCalculator genotypicSimilarityCalculator;

    [Storable]
    private readonly ISymbolicExpressionTreeNodeEqualityComparer comparer;
    private QueryMatch qm;

    public IFixedValueParameter<IntValue> MinimumSchemaLengthParameter {
      get { return (IFixedValueParameter<IntValue>)Parameters[MinimumSchemaLengthParameterName]; }
    }

    public SymbolicDataAnalysisSchemaFrequencyAnalyzer() {
      comparer = new SymbolicExpressionTreeNodeEqualityComparer {
        MatchConstantValues = false,
        MatchVariableNames = true,
        MatchVariableWeights = false
      };
      qm = new QueryMatch(comparer) { MatchParents = true };
      phenotypicSimilarityCalculator = new SymbolicExpressionTreePhenotypicSimilarityCalculator();
      genotypicSimilarityCalculator = new SymbolicExpressionTreeBottomUpSimilarityCalculator { SolutionVariableName = "SymbolicExpressionTree" };
      Parameters.Add(new FixedValueParameter<IntValue>(MinimumSchemaLengthParameterName, new IntValue(10)));
    }

    protected SymbolicDataAnalysisSchemaFrequencyAnalyzer(SymbolicDataAnalysisSchemaFrequencyAnalyzer original,
      Cloner cloner) : base(original, cloner) {
      comparer = original.comparer;
      phenotypicSimilarityCalculator = original.phenotypicSimilarityCalculator;
      genotypicSimilarityCalculator = original.genotypicSimilarityCalculator;
      qm = new QueryMatch(comparer) { MatchParents = true };
    }

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

    [StorableConstructor]
    protected SymbolicDataAnalysisSchemaFrequencyAnalyzer(bool deserializing) : base(deserializing) { }


    [StorableHook(HookType.AfterDeserialization)]
    private void AfterDeserialization() {
      qm = new QueryMatch(comparer) { MatchParents = true };
    }

    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 || Generation.Value == 0)
        return base.Apply();

      var minimumSchemaLength = MinimumSchemaLengthParameter.Value.Value;
      var vertices = PopulationGraph.GetByRank(Generation.Value).Cast<IGenealogyGraphNode<ISymbolicExpressionTree>>().ToList();
      var formatter = new SymbolicExpressionTreeStringFormatter { Indent = false, AppendNewLines = false };

      var schemas = SchemaCreator.GenerateSchemas(vertices, minimumSchemaLength).ToList();
      var trees = vertices.Select(x => x.Data).ToList();
      var qualities = vertices.Select(x => x.Quality).ToList();
      var scopes = ExecutionContext.Scope.SubScopes; // the scopes of all the individuals, needed because the tree evaluated values are stored in the scope and we use them for the phenotypic similarity

      var matrix = new DoubleMatrix(schemas.Count, 5) {
        RowNames = schemas.Select(x => formatter.Format(x.Root.GetSubtree(0).GetSubtree(0))),
        ColumnNames = new[] { "Avg. Length", "Avg. Quality", "Relative Frequency", "Avg. Phen. Sim.", "Avg. Gen. Sim" },
        SortableView = true
      };

      for (int i = 0; i < schemas.Count; ++i) {
        var schema = schemas[i];
        int count = 0;
        double avgLength = 0;
        double avgQuality = 0;
        var matchingScopes = new ScopeList();
        for (int j = 0; j < trees.Count; ++j) {
          var tree = trees[j];
          if (qm.Match(tree, schema)) {
            count++;
            avgLength += tree.Length;
            avgQuality += qualities[j];
            matchingScopes.Add(scopes[j]);
          }
        }
        avgLength /= count;
        avgQuality /= count;
        double relativeFreq = (double)count / trees.Count;
        double avgPhenotypicSimilarity = SchemaEvaluator.CalculateSimilarity(matchingScopes, phenotypicSimilarityCalculator, true, 4);
        double avgGenotypicSimilarity = SchemaEvaluator.CalculateSimilarity(matchingScopes, genotypicSimilarityCalculator, true, 4);

        matrix[i, 0] = avgLength;
        matrix[i, 1] = avgQuality;
        matrix[i, 2] = relativeFreq;
        matrix[i, 3] = avgPhenotypicSimilarity;
        matrix[i, 4] = avgGenotypicSimilarity;
      }

      if (Results.ContainsKey("Schema Frequencies")) {
        var result = Results["Schema Frequencies"];
        result.Value = matrix;
      } else {
        var result = new Result("Schema Frequencies", matrix);
        Results.Add(result);
      }

      return base.Apply();
    }
  }
}