#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2012 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.Algorithms.GeneticAlgorithm;
using HeuristicLab.Collections;
using HeuristicLab.Common;
using HeuristicLab.Core;
using HeuristicLab.Data;
using HeuristicLab.Encodings.ParameterConfigurationEncoding;
using HeuristicLab.Optimization;
using HeuristicLab.Parameters;
using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
using HeuristicLab.PluginInfrastructure;
using HeuristicLab.Problems.DataAnalysis;
using HeuristicLab.Problems.TestFunctions;

namespace HeuristicLab.Problems.MetaOptimization {
  /// <summary>
  /// 
  /// </summary>
  [Item("Meta Optimization Problem", "Represents a meta-optimization problem.")]
  [Creatable("Problems")]
  [StorableClass]
  public sealed class MetaOptimizationProblem : SingleObjectiveHeuristicOptimizationProblem<IParameterConfigurationEvaluator, IParameterConfigurationCreator>, IStorableContent {
    public string Filename { get; set; }

    public const string AlgorithmTypeParameterName = "AlgorithmType";
    public const string ProblemTypeParameterName = "ProblemType";
    public const string ProblemsParameterName = "Problems";
    public const string ParameterConfigurationTreeParameterName = "ParameterConfiguration";
    public const string RepetitionsParameterName = "Repetitions";
    public const string QualityMeasureNameName = "QualityMeasureName";

    public const string IntValueManipulatorParameterName = "IntValueManipulator";
    public const string DoubleValueManipulatorParameterName = "DoubleValueManipulator";
    public const string IntValueCrossoverParameterName = "IntValueCrossover";
    public const string DoubleValueCrossoverParameterName = "DoubleValueCrossover";
    public const string QualityWeightParameterName = "QualityWeight";
    public const string StandardDeviationWeightParameterName = "StandardDeviationWeight";
    public const string EvaluatedSolutionsWeightParameterName = "EvaluatedSolutionsWeight";


    #region Parameter Properties
    public IValueParameter<ConstrainedTypeValue<IAlgorithm>> AlgorithmTypeParameter {
      get { return (ValueParameter<ConstrainedTypeValue<IAlgorithm>>)Parameters[AlgorithmTypeParameterName]; }
    }
    public IValueParameter<ConstrainedTypeValue<IProblem>> ProblemTypeParameter {
      get { return (ValueParameter<ConstrainedTypeValue<IProblem>>)Parameters[ProblemTypeParameterName]; }
    }
    public IValueParameter<ConstrainedItemList<IProblem>> ProblemsParameter {
      get { return (ValueParameter<ConstrainedItemList<IProblem>>)Parameters[ProblemsParameterName]; }
    }
    public IValueParameter<ParameterConfigurationTree> ParameterConfigurationTreeParameter {
      get { return (OptionalValueParameter<ParameterConfigurationTree>)Parameters[ParameterConfigurationTreeParameterName]; }
    }
    public IValueParameter<IntValue> RepetitionsParameter {
      get { return (ValueParameter<IntValue>)Parameters[RepetitionsParameterName]; }
    }
    public IConstrainedValueParameter<IIntValueManipulator> IntValueManipulatorParameter {
      get { return (ConstrainedValueParameter<IIntValueManipulator>)Parameters[IntValueManipulatorParameterName]; }
    }
    public IConstrainedValueParameter<IDoubleValueManipulator> DoubleValueManipulatorParameter {
      get { return (ConstrainedValueParameter<IDoubleValueManipulator>)Parameters[DoubleValueManipulatorParameterName]; }
    }
    public IValueParameter<StringValue> QualityMeasureNameParameter {
      get { return (ValueParameter<StringValue>)Parameters[QualityMeasureNameName]; }
    }
    public IConstrainedValueParameter<IIntValueCrossover> IntValueCrossoverParameter {
      get { return (ConstrainedValueParameter<IIntValueCrossover>)Parameters[IntValueCrossoverParameterName]; }
    }
    public IConstrainedValueParameter<IDoubleValueCrossover> DoubleValueCrossoverParameter {
      get { return (ConstrainedValueParameter<IDoubleValueCrossover>)Parameters[DoubleValueCrossoverParameterName]; }
    }
    #endregion

    #region Properties
    public IAlgorithm Algorithm {
      get { return CreateAlgorithm(AlgorithmType.Value, Problems.FirstOrDefault()); }
    }
    public ConstrainedTypeValue<IAlgorithm> AlgorithmType {
      get { return AlgorithmTypeParameter.Value; }
      set { AlgorithmTypeParameter.Value = value; }
    }
    public ConstrainedTypeValue<IProblem> ProblemType {
      get { return ProblemTypeParameter.Value; }
      set { ProblemTypeParameter.Value = value; }
    }
    public ConstrainedItemList<IProblem> Problems {
      get { return ProblemsParameter.Value; }
      set { ProblemsParameter.Value = value; }
    }
    public ParameterConfigurationTree ParameterConfigurationTree {
      get { return ParameterConfigurationTreeParameter.Value; }
      set { ParameterConfigurationTreeParameter.Value = value; }
    }
    public IntValue Repetitions {
      get { return RepetitionsParameter.Value; }
      set { RepetitionsParameter.Value = value; }
    }
    private BestParameterConfigurationAnalyzer BestParameterConfigurationAnalyzer {
      get { return Operators.OfType<BestParameterConfigurationAnalyzer>().FirstOrDefault(); }
    }
    private ReferenceQualityAnalyzer ReferenceQualityAnalyzer {
      get { return Operators.OfType<ReferenceQualityAnalyzer>().FirstOrDefault(); }
    }
    private SolutionCacheAnalyzer RunsAnalyzer {
      get { return Operators.OfType<SolutionCacheAnalyzer>().FirstOrDefault(); }
    }
    private PMOPopulationDiversityAnalyzer PMOPopulationDiversityAnalyzer {
      get { return Operators.OfType<PMOPopulationDiversityAnalyzer>().FirstOrDefault(); }
    }
    private PMOProblemQualitiesAnalyzer PMOProblemQualitiesAnalyzer {
      get { return Operators.OfType<PMOProblemQualitiesAnalyzer>().FirstOrDefault(); }
    }
    private PMOBestSolutionHistoryAnalyzer PMOBestSolutionHistoryAnalyzer {
      get { return Operators.OfType<PMOBestSolutionHistoryAnalyzer>().FirstOrDefault(); }
    }
    #endregion

    #region Constructors and Cloning
    public MetaOptimizationProblem()
      : base() {
      Parameters.Add(new ValueParameter<ConstrainedTypeValue<IAlgorithm>>(AlgorithmTypeParameterName, "The algorithm which's parameters should be optimized.", new ConstrainedTypeValue<IAlgorithm>(typeof(GeneticAlgorithm))));
      Parameters.Add(new ValueParameter<ConstrainedTypeValue<IProblem>>(ProblemTypeParameterName, "The problem type.", new ConstrainedTypeValue<IProblem>()));
      Parameters.Add(new ValueParameter<ConstrainedItemList<IProblem>>(ProblemsParameterName, "The problems that should be evaluated.", new ConstrainedItemList<IProblem>()));
      Parameters.Add(new OptionalValueParameter<ParameterConfigurationTree>(ParameterConfigurationTreeParameterName, "Tree of algorithm parameters that should be optimized.")); // needs to be optional, when last problem is removed from list, it must be set null
      Parameters.Add(new ValueParameter<IntValue>(RepetitionsParameterName, "The number of evaluations for each problem.", new IntValue(3)));
      Parameters.Add(new ValueParameter<StringValue>(QualityMeasureNameName, "The name of the quality result of the base-level algorithm. Subresults can be accessed by dot separator.", new StringValue("BestQuality")));

      var validIntManipulators = new ItemSet<IIntValueManipulator>(ApplicationManager.Manager.GetInstances<IIntValueManipulator>());
      var validDoubleManipulators = new ItemSet<IDoubleValueManipulator>(ApplicationManager.Manager.GetInstances<IDoubleValueManipulator>());
      var validIntCrossovers = new ItemSet<IIntValueCrossover>(ApplicationManager.Manager.GetInstances<IIntValueCrossover>());
      var validDoubleCrossovers = new ItemSet<IDoubleValueCrossover>(ApplicationManager.Manager.GetInstances<IDoubleValueCrossover>());
      Parameters.Add(new ConstrainedValueParameter<IIntValueManipulator>(IntValueManipulatorParameterName, validIntManipulators, validIntManipulators.Where(x => x.GetType() == typeof(NormalIntValueManipulator)).SingleOrDefault()));
      Parameters.Add(new ConstrainedValueParameter<IDoubleValueManipulator>(DoubleValueManipulatorParameterName, validDoubleManipulators, validDoubleManipulators.Where(x => x.GetType() == typeof(NormalDoubleValueManipulator)).SingleOrDefault()));
      Parameters.Add(new ConstrainedValueParameter<IIntValueCrossover>(IntValueCrossoverParameterName, validIntCrossovers, validIntCrossovers.Where(x => x.GetType() == typeof(NormalIntValueCrossover)).SingleOrDefault()));
      Parameters.Add(new ConstrainedValueParameter<IDoubleValueCrossover>(DoubleValueCrossoverParameterName, validDoubleCrossovers, validDoubleCrossovers.Where(x => x.GetType() == typeof(NormalDoubleValueCrossover)).SingleOrDefault()));

      Parameters.Add(new ValueParameter<DoubleValue>(QualityWeightParameterName, new DoubleValue(1)));
      Parameters.Add(new ValueParameter<DoubleValue>(StandardDeviationWeightParameterName, new DoubleValue(0.01)));
      Parameters.Add(new ValueParameter<DoubleValue>(EvaluatedSolutionsWeightParameterName, new DoubleValue(0.0005)));

      Maximization = new BoolValue(false);
      SolutionCreator = new RandomParameterConfigurationCreator();
      Evaluator = new PMOEvaluator();

      InitializeOperators();
      RegisterParameterEvents();
      ParameterizeAnalyzer();
      ParameterizeSolutionCreator();
      ParameterizeEvaluator();
      ParameterizeOperators();

      AlgorithmTypeParameter_ValueChanged(this, EventArgs.Empty);
    }

    [StorableConstructor]
    private MetaOptimizationProblem(bool deserializing) : base(deserializing) { }
    private MetaOptimizationProblem(MetaOptimizationProblem original, Cloner cloner)
      : base(original, cloner) {
      this.RegisterParameterEvents();
    }
    public override IDeepCloneable Clone(Cloner cloner) {
      return new MetaOptimizationProblem(this, cloner);
    }
    #endregion

    #region Helpers
    [StorableHook(HookType.AfterDeserialization)]
    private void AfterDeserializationHook() {
      if (!Parameters.ContainsKey(QualityMeasureNameName)) Parameters.Add(new ValueParameter<StringValue>(QualityMeasureNameName, "The name of the quality result of the base-level algorithm. Subresults can be accessed by dot separator.", new StringValue("BestQuality"))); // backwards compatibility
      RegisterParameterEvents();
    }
    private void RegisterParameterEvents() {
      SolutionCreatorParameter.ValueChanged += new EventHandler(SolutionCreatorParameter_ValueChanged);
      EvaluatorParameter.ValueChanged += new EventHandler(EvaluatorParameter_ValueChanged);
      Evaluator.QualityParameter.ActualNameChanged += new EventHandler(Evaluator_QualityParameter_ActualNameChanged);
      AlgorithmTypeParameter.ValueChanged += new EventHandler(AlgorithmTypeParameter_ValueChanged);
      AlgorithmType.ValueChanged += new EventHandler(AlgorithmType_ValueChanged);
      ProblemTypeParameter.ValueChanged += new EventHandler(ProblemTypeParameter_ValueChanged);
      ProblemType.ValueChanged += new EventHandler(ProblemType_ValueChanged);
      Problems.ItemsAdded += new Collections.CollectionItemsChangedEventHandler<Collections.IndexedItem<IProblem>>(Problems_ItemsAdded);
      Problems.ItemsRemoved += new Collections.CollectionItemsChangedEventHandler<Collections.IndexedItem<IProblem>>(Problems_ItemsRemoved);
    }

    private void InitializeOperators() {
      Operators.AddRange(ApplicationManager.Manager.GetInstances<IParameterConfigurationOperator>().Cast<IOperator>());
      Operators.Add(new ReferenceQualityAnalyzer());
      Operators.Add(new BestParameterConfigurationAnalyzer());
      Operators.Add(new SolutionCacheAnalyzer());
      Operators.Add(new PMOPopulationDiversityAnalyzer());
      Operators.Add(new PMOProblemQualitiesAnalyzer());
      Operators.Add(new PMOBestSolutionHistoryAnalyzer());
      Operators.Add(new PopulationAnalyzer());
    }
    private void ParameterizeSolutionCreator() {
    }
    private void ParameterizeEvaluator() {
      ((PMOEvaluator)Evaluator).ParameterConfigurationParameter.ActualName = ((RandomParameterConfigurationCreator)SolutionCreator).ParameterConfigurationParameter.ActualName;
    }
    private void ParameterizeAnalyzer() {
      if (BestParameterConfigurationAnalyzer != null) {
        BestParameterConfigurationAnalyzer.ParameterConfigurationParameter.ActualName = ((RandomParameterConfigurationCreator)SolutionCreator).ParameterConfigurationParameter.ActualName;
      }
      if (ReferenceQualityAnalyzer != null) {
        ReferenceQualityAnalyzer.ParameterConfigurationParameter.ActualName = ((RandomParameterConfigurationCreator)SolutionCreator).ParameterConfigurationParameter.ActualName;
      }
      if (RunsAnalyzer != null) {
        RunsAnalyzer.ParameterConfigurationParameter.ActualName = ((RandomParameterConfigurationCreator)SolutionCreator).ParameterConfigurationParameter.ActualName;
      }
      if (PMOPopulationDiversityAnalyzer != null) {
        PMOPopulationDiversityAnalyzer.SolutionParameter.ActualName = ((RandomParameterConfigurationCreator)SolutionCreator).ParameterConfigurationParameter.ActualName;
        PMOPopulationDiversityAnalyzer.StoreHistoryParameter.Value.Value = true;
      }
      if (PMOProblemQualitiesAnalyzer != null) {
        PMOProblemQualitiesAnalyzer.ParameterConfigurationParameter.ActualName = ((RandomParameterConfigurationCreator)SolutionCreator).ParameterConfigurationParameter.ActualName;
      }
      if (PMOBestSolutionHistoryAnalyzer != null) {
        PMOBestSolutionHistoryAnalyzer.ParameterConfigurationParameter.ActualName = ((RandomParameterConfigurationCreator)SolutionCreator).ParameterConfigurationParameter.ActualName;
      }
    }
    private void ParameterizeOperators() {
      foreach (IParameterConfigurationCrossover op in Operators.OfType<IParameterConfigurationCrossover>()) {
        op.ParentsParameter.ActualName = ((RandomParameterConfigurationCreator)SolutionCreator).ParameterConfigurationParameter.ActualName;
        op.ChildParameter.ActualName = ((RandomParameterConfigurationCreator)SolutionCreator).ParameterConfigurationParameter.ActualName;
      }
      foreach (IParameterConfigurationManipulator op in Operators.OfType<IParameterConfigurationManipulator>()) {
        op.ParameterConfigurationTreeParameter.ActualName = ((RandomParameterConfigurationCreator)SolutionCreator).ParameterConfigurationParameter.ActualName;
      }
    }

    #endregion

    #region Events

    private void SolutionCreatorParameter_ValueChanged(object sender, EventArgs e) {
      ParameterizeSolutionCreator();
      ParameterizeEvaluator();
      ParameterizeAnalyzer();
      ParameterizeOperators();
      OnSolutionCreatorChanged();
    }
    private void EvaluatorParameter_ValueChanged(object sender, EventArgs e) {
      Evaluator.QualityParameter.ActualNameChanged += new EventHandler(Evaluator_QualityParameter_ActualNameChanged);
      ParameterizeEvaluator();
      ParameterizeAnalyzer();
      OnEvaluatorChanged();
    }
    private void Evaluator_QualityParameter_ActualNameChanged(object sender, EventArgs e) {
      ParameterizeAnalyzer();
    }
    private void AlgorithmTypeParameter_ValueChanged(object sender, EventArgs e) {
      AlgorithmType_ValueChanged(sender, e);
    }

    private void AlgorithmType_ValueChanged(object sender, EventArgs e) {
      IAlgorithm instance = (IAlgorithm)Activator.CreateInstance(AlgorithmType.Value);
      this.ProblemType.ValidTypes = ApplicationManager.Manager.GetTypes(instance.ProblemType, true).ToList();
      var newProblemType = this.ProblemType.ValidTypes.SingleOrDefault(t => t == typeof(SingleObjectiveTestFunctionProblem)) ?? this.ProblemType.ValidTypes.Where(t => t != typeof(MetaOptimizationProblem)).FirstOrDefault();
      if (this.ProblemType.Value != newProblemType)
        this.ProblemType.Value = newProblemType; // ProblemType_ValueChanged will add one problem and create ParameterConfigurationTree
      else
        ProblemType_ValueChanged(this, EventArgs.Empty); // call explicitly
    }

    private void ProblemTypeParameter_ValueChanged(object sender, EventArgs e) {
      ProblemType_ValueChanged(sender, e);
    }

    private void ProblemType_ValueChanged(object sender, EventArgs e) {
      Problems.Clear();
      Problems.Type = ProblemType.Value;
      Problems.Add((IProblem)Activator.CreateInstance(this.ProblemType.Value));
    }

    private void Problems_ItemsAdded(object sender, CollectionItemsChangedEventArgs<IndexedItem<IProblem>> e) {
      // the first problem in the list is always the instance for the algorithm - this way some basic wiring between problem and algorithm can be sustained
      if (e.Items.Single().Index == 0) {
        ParameterConfigurationTreeParameter.ActualValue = new ParameterConfigurationTree(CreateAlgorithm(AlgorithmType.Value, e.Items.Single().Value), e.Items.Single().Value);

        // special for DataAnalysisProblem: Because of wiring between algorithm and problem, ParameterConfigurationTree needs to be recreated on Reset event
        var dap = e.Items.Single().Value as IDataAnalysisProblem;
        if (dap != null) {
          dap.Reset += new EventHandler(DataAnalysisProblem_Reset);
        }
      }
    }

    private void Problems_ItemsRemoved(object sender, CollectionItemsChangedEventArgs<IndexedItem<IProblem>> e) {
      if (e.Items.Single().Index == 0) {
        ParameterConfigurationTreeParameter.ActualValue = null;

        var dap = e.Items.Single().Value as IDataAnalysisProblem;
        if (dap != null) {
          dap.Reset -= new EventHandler(DataAnalysisProblem_Reset);
        }
      }
    }

    private void DataAnalysisProblem_Reset(object sender, EventArgs e) {
      ParameterConfigurationTreeParameter.ActualValue = new ParameterConfigurationTree(CreateAlgorithm(AlgorithmType.Value, Problems.First()), Problems.First());
    }
    #endregion

    private IAlgorithm CreateAlgorithm(Type algorithmType, IProblem problem) {
      IAlgorithm algorithm = (IAlgorithm)Activator.CreateInstance(algorithmType);
      algorithm.Problem = problem;
      return algorithm;
    }

    public void ImportAlgorithm(IAlgorithm algorithm) {
      AlgorithmType.Value = algorithm.GetType();
      if (algorithm.Problem != null) ProblemType.Value = algorithm.Problem.GetType();
      if (algorithm.Problem != null) {
        Problems.Clear();
        Problems.Add((IProblem)algorithm.Problem);
      }
      ParameterConfigurationTreeParameter.ActualValue = new ParameterConfigurationTree(algorithm, Problems.First());
    }
  }
}