#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.Common;
using HeuristicLab.Core;
using HeuristicLab.Data;
using HeuristicLab.Operators;
using HeuristicLab.Optimization;
using HeuristicLab.Optimization.Operators;
using HeuristicLab.Parameters;
using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
using HeuristicLab.Problems.GeneralizedQuadraticAssignment.Common;
using HeuristicLab.Selection;

namespace HeuristicLab.Problems.GeneralizedQuadraticAssignment.Algorithms {
  [Item("GRASP+PR MainLoop", "The main loop that implements the behavior of the GRASP+PR algorithm.")]
  [StorableClass]
  public class GRASPWithPathRelinkingMainLoop : AlgorithmOperator {
    public IValueLookupParameter<IOperator> SolutionCreatorParameter {
      get { return (IValueLookupParameter<IOperator>)Parameters["SolutionCreator"]; }
    }
    public IValueLookupParameter<IOperator> EvaluatorParameter {
      get { return (IValueLookupParameter<IOperator>)Parameters["Evaluator"]; }
    }
    public IValueLookupParameter<IntValue> EvaluatedSolutionsParameter {
      get { return (IValueLookupParameter<IntValue>)Parameters["EvaluatedSolutions"]; }
    }
    public IValueLookupParameter<IntValue> MaximumIterationsParameter {
      get { return (IValueLookupParameter<IntValue>)Parameters["MaximumIterations"]; }
    }
    public IValueLookupParameter<ResultCollection> ResultsParameter {
      get { return (IValueLookupParameter<ResultCollection>)Parameters["Results"]; }
    }
    public IValueLookupParameter<IntValue> EliteSetSizeParameter {
      get { return (IValueLookupParameter<IntValue>)Parameters["EliteSetSize"]; }
    }
    public IValueLookupParameter<IOperator> LocalImprovementParameter {
      get { return (IValueLookupParameter<IOperator>)Parameters["LocalImprovement"]; }
    }
    public IValueLookupParameter<IOperator> PathRelinkingParameter {
      get { return (IValueLookupParameter<IOperator>)Parameters["PathRelinking"]; }
    }
    public IValueLookupParameter<IOperator> EliteSetReplacerParameter {
      get { return (IValueLookupParameter<IOperator>)Parameters["EliteSetReplacer"]; }
    }
    public IValueLookupParameter<IOperator> AnalyzerParameter {
      get { return (IValueLookupParameter<IOperator>)Parameters["Analyzer"]; }
    }

    [StorableConstructor]
    protected GRASPWithPathRelinkingMainLoop(bool deserializing) : base(deserializing) { }
    protected GRASPWithPathRelinkingMainLoop(GRASPWithPathRelinkingMainLoop original, Cloner cloner)
      : base(original, cloner) { }
    public GRASPWithPathRelinkingMainLoop()
      : base() {
      Parameters.Add(new ValueLookupParameter<IOperator>("SolutionCreator", "The solution creation procedure which ideally should be a greedy initialization heuristic."));
      Parameters.Add(new ValueLookupParameter<IOperator>("Evaluator", "The evaluator which calculates the fitness of a solutions."));
      Parameters.Add(new ValueLookupParameter<IntValue>("EvaluatedSolutions", "The number of evaluated solutions."));
      Parameters.Add(new ValueLookupParameter<IntValue>("MaximumIterations", "The number of maximum iterations that should be performed."));
      Parameters.Add(new ValueLookupParameter<ResultCollection>("Results", "Specifies where the results are stored."));
      Parameters.Add(new ValueLookupParameter<IntValue>("EliteSetSize", "The size of the elite set."));
      Parameters.Add(new ValueLookupParameter<IOperator>("LocalImprovement", "The operator which performs the local improvement."));
      Parameters.Add(new ValueLookupParameter<IOperator>("PathRelinking", "The operator which performs the path relinking."));
      Parameters.Add(new ValueLookupParameter<IOperator>("EliteSetReplacer", "The operator that replaces elements in the elite set."));
      Parameters.Add(new ValueLookupParameter<IOperator>("Analyzer", "The analyzer that is to be applied."));

      var variableCreator1 = new VariableCreator();
      variableCreator1.CollectedValues.Add(new ValueParameter<IntValue>("Iterations", new IntValue(0)));

      var variableCreator2 = new VariableCreator();
      variableCreator2.CollectedValues.Add(new ValueParameter<IntValue>("ActualEliteSetSize", new IntValue(0)));
      variableCreator2.Name = "ActualEliteSetSize = 0";

      var subScopesCounter1 = new SubScopesCounter();
      subScopesCounter1.Name = "ActualEliteSetSize += |SubScopes|";
      subScopesCounter1.ValueParameter.ActualName = "ActualEliteSetSize";

      var comparator1 = new Comparator();
      comparator1.Name = "ActualEliteSetSize >= MinimumEliteSetSize";
      comparator1.Comparison.Value = ComparisonType.GreaterOrEqual;
      comparator1.LeftSideParameter.ActualName = "ActualEliteSetSize";
      comparator1.RightSideParameter.ActualName = EliteSetSizeParameter.ActualName;
      comparator1.ResultParameter.ActualName = "SizeOkay";

      var conditionalBranch1 = new ConditionalBranch();
      conditionalBranch1.Name = "Elite set has at least ρ elements";
      conditionalBranch1.ConditionParameter.ActualName = "SizeOkay";

      var selector1 = new RandomSelector();
      selector1.NumberOfSelectedSubScopesParameter.Value = new IntValue(1);
      selector1.CopySelected.Value = true;

      var selector2 = new RandomSelector();
      selector2.NumberOfSelectedSubScopesParameter.Value = new IntValue(0);

      var ssp1 = new SubScopesProcessor();

      var eo1 = new EmptyOperator();

      var solutionsCreator = new SolutionsCreator();
      solutionsCreator.EvaluatorParameter.ActualName = EvaluatorParameter.Name;
      solutionsCreator.SolutionCreatorParameter.ActualName = SolutionCreatorParameter.Name;
      solutionsCreator.NumberOfSolutions = new IntValue(1);

      var subScopesCounter2 = new SubScopesCounter();
      subScopesCounter2.Name = "Count subscopes";
      subScopesCounter2.ValueParameter.ActualName = "SolutionScopes";

      var comparator2 = new Comparator();
      comparator2.Name = "SolutionScopes == 2";
      comparator2.Comparison.Value = ComparisonType.Equal;
      comparator2.LeftSideParameter.ActualName = "SolutionScopes";
      comparator2.RightSideParameter.Value = new IntValue(2);
      comparator2.ResultParameter.ActualName = "PerformPR";

      var conditionalBranch2 = new ConditionalBranch();
      conditionalBranch2.Name = "Path relinking?";
      conditionalBranch2.ConditionParameter.ActualName = "PerformPR";

      var ssp2 = new SubScopesProcessor();

      var eo2 = new EmptyOperator();

      var placeholder1 = new Placeholder();
      placeholder1.Name = "(LocalImprovement)";
      placeholder1.OperatorParameter.ActualName = LocalImprovementParameter.Name;

      var childrenCreator = new ChildrenCreator();
      childrenCreator.ParentsPerChild = new IntValue(2);

      var placeholder2 = new Placeholder();
      placeholder2.Name = "(PathRelinking)";
      placeholder2.OperatorParameter.ActualName = PathRelinkingParameter.Name;

      var subScopesRemover = new SubScopesRemover();
      subScopesRemover.RemoveAllSubScopes = true;

      var ssp3 = new SubScopesProcessor();

      var placeholder3 = new Placeholder();
      placeholder3.Name = "(LocalImprovement)";
      placeholder3.OperatorParameter.ActualName = LocalImprovementParameter.Name;

      var placeholder4 = new Placeholder();
      placeholder4.Name = "(Replacer)";
      placeholder4.OperatorParameter.ActualName = EliteSetReplacerParameter.Name;

      var counter = new IntCounter();
      counter.Name = "Iterations++";
      counter.ValueParameter.ActualName = "Iterations";
      counter.Increment = new IntValue(1);

      var analyzer1 = new Placeholder();
      analyzer1.Name = "(Analyzer)";
      analyzer1.OperatorParameter.ActualName = AnalyzerParameter.Name;

      var comparator3 = new Comparator();
      comparator3.Name = "Iterations >= MaximumIterations";
      comparator3.Comparison.Value = ComparisonType.GreaterOrEqual;
      comparator3.LeftSideParameter.ActualName = "Iterations";
      comparator3.RightSideParameter.ActualName = MaximumIterationsParameter.Name;
      comparator3.ResultParameter.ActualName = "TerminatedByIteration";

      var conditionalBranch3 = new ConditionalBranch();
      conditionalBranch3.Name = "Terminate by Iterations?";
      conditionalBranch3.ConditionParameter.ActualName = "TerminatedByIteration";

      OperatorGraph.InitialOperator = variableCreator1;
      variableCreator1.Successor = variableCreator2;
      variableCreator2.Successor = subScopesCounter1;
      subScopesCounter1.Successor = comparator1;
      comparator1.Successor = conditionalBranch1;
      conditionalBranch1.TrueBranch = selector1;
      conditionalBranch1.FalseBranch = selector2;
      conditionalBranch1.Successor = ssp1;
      ssp1.Operators.Add(eo1);
      ssp1.Operators.Add(solutionsCreator);
      ssp1.Successor = placeholder4;
      eo1.Successor = null;
      solutionsCreator.Successor = subScopesCounter2;
      subScopesCounter2.Successor = comparator2;
      comparator2.Successor = conditionalBranch2;
      conditionalBranch2.TrueBranch = ssp2;
      conditionalBranch2.FalseBranch = null;
      conditionalBranch2.Successor = ssp3;
      ssp2.Operators.Add(eo2);
      ssp2.Operators.Add(placeholder1);
      ssp2.Successor = null;
      eo2.Successor = null;
      placeholder1.Successor = childrenCreator;
      childrenCreator.Successor = placeholder2;
      placeholder2.Successor = subScopesRemover;
      subScopesRemover.Successor = null;
      ssp3.Operators.Add(placeholder3);
      ssp3.Successor = null;
      placeholder4.Successor = counter;
      counter.Successor = analyzer1;
      analyzer1.Successor = comparator3;
      comparator3.Successor = conditionalBranch3;
      conditionalBranch3.TrueBranch = null;
      conditionalBranch3.FalseBranch = variableCreator2;
      conditionalBranch3.Successor = null;
    }

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

    private void Parameterize() {
      var operators = OperatorGraph.InitialOperator.Walk().ToArray();

      foreach (var solutionsCreator in operators.OfType<SolutionsCreator>()) {
        solutionsCreator.SolutionCreatorParameter.ActualName = SolutionCreatorParameter.Name;
        solutionsCreator.EvaluatorParameter.ActualName = EvaluatorParameter.Name;
      }
    }

    public event EventHandler ProblemChanged;
    protected virtual void OnProblemChanged() {
      Parameterize();
      var handler = ProblemChanged;
      if (handler != null) handler(this, EventArgs.Empty);
    }
  }
}