#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2013 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.Collections.Generic;
using System.Linq;
using System.Text;
using HeuristicLab.Optimization;
using HeuristicLab.Core;
using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
using HeuristicLab.Data;
using HeuristicLab.Common;
using HeuristicLab.Parameters;
using HeuristicLab.Operators;

namespace HeuristicLab.Problems.VehicleRouting.Encodings.Alba {
  [Item("AlbaLambdaInterchangeLocalImprovementOperator", "Takes a solution and finds the local optimum with respect to the lambda interchange neighborhood by decending along the steepest gradient.")]
  [StorableClass]
  public class AlbaLambdaInterchangeLocalImprovementOperator : SingleSuccessorOperator, IStochasticOperator, ILocalImprovementOperator {
    public Type ProblemType {
      get { return typeof(VehicleRoutingProblem); }
    }

    [Storable]
    private VehicleRoutingProblem problem;
    public IProblem Problem {
      get { return problem; }
      set { problem = (VehicleRoutingProblem)value; }
    }

    public IValueLookupParameter<IntValue> MaximumIterationsParameter {
      get { return (IValueLookupParameter<IntValue>)Parameters["MaximumIterations"]; }
    }

    public ILookupParameter<IntValue> EvaluatedSolutionsParameter {
      get { return (ILookupParameter<IntValue>)Parameters["EvaluatedSolutions"]; }
    }

    public ILookupParameter<ResultCollection> ResultsParameter {
      get { return (ILookupParameter<ResultCollection>)Parameters["Results"]; }
    }

    public ILookupParameter<IVRPEncoding> VRPToursParameter {
      get { return (ILookupParameter<IVRPEncoding>)Parameters["VRPTours"]; }
    }

    public ILookupParameter<DoubleValue> QualityParameter {
      get { return (ILookupParameter<DoubleValue>)Parameters["Quality"]; }
    }

    public IValueParameter<IntValue> LambdaParameter {
      get { return (IValueParameter<IntValue>)Parameters["Lambda"]; }
    }

    public IValueParameter<IntValue> SampleSizeParameter {
      get { return (IValueParameter<IntValue>)Parameters["SampleSize"]; }
    }

    public ILookupParameter<IRandom> RandomParameter {
      get { return (ILookupParameter<IRandom>)Parameters["Random"]; }
    }

    [StorableConstructor]
    protected AlbaLambdaInterchangeLocalImprovementOperator(bool deserializing) : base(deserializing) { }
    protected AlbaLambdaInterchangeLocalImprovementOperator(AlbaLambdaInterchangeLocalImprovementOperator original, Cloner cloner)
      : base(original, cloner) {
      this.problem = cloner.Clone(original.problem);
    }
    public AlbaLambdaInterchangeLocalImprovementOperator()
      : base() {
      Parameters.Add(new ValueLookupParameter<IntValue>("MaximumIterations", "The maximum amount of iterations that should be performed (note that this operator will abort earlier when a local optimum is reached.", new IntValue(10000)));
      Parameters.Add(new LookupParameter<IntValue>("EvaluatedSolutions", "The amount of evaluated solutions (here a move is counted only as 4/n evaluated solutions with n being the length of the permutation)."));
      Parameters.Add(new LookupParameter<ResultCollection>("Results", "The collection where to store results."));
      Parameters.Add(new LookupParameter<IVRPEncoding>("VRPTours", "The VRP tours to be manipulated."));
      Parameters.Add(new LookupParameter<DoubleValue>("Quality", "The quality value of the assignment."));
      Parameters.Add(new ValueParameter<IntValue>("Lambda", "The lambda value.", new IntValue(1)));
      Parameters.Add(new ValueParameter<IntValue>("SampleSize", "The number of moves to generate.", new IntValue(2000)));
      Parameters.Add(new LookupParameter<IRandom>("Random", "The random number generator."));
    }

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

    public static void Apply(AlbaEncoding solution, int maxIterations, 
      int lambda, int samples, IRandom random, ref double quality, out int evaluatedSolutions, 
      DoubleMatrix distanceMatrix, IntValue vehicles, DoubleArray dueTime, DoubleArray serviceTime, DoubleArray readyTime,
      DoubleArray demand, DoubleValue capacity, 
      DoubleMatrix coordinates, DoubleValue fleetUsageFactor, DoubleValue timeFactor, DoubleValue distanceFactor,
      DoubleValue overloadPenalty, DoubleValue tardinessPenalty, BoolValue useDistanceMatrix) {
      ValueLookupParameter<DoubleMatrix> distanceMatrixParameter = new ValueLookupParameter<DoubleMatrix>("DistanceMatrix", distanceMatrix);

      evaluatedSolutions = 0;

      for (int i = 0; i < maxIterations; i++) {
        AlbaLambdaInterchangeMove bestMove = null;
        foreach (AlbaLambdaInterchangeMove move in AlbaStochasticLambdaInterchangeMultiMoveGenerator.GenerateAllMoves(solution, lambda, samples, random)) {
          double moveQuality =
            AlbaLambdaInterchangeMoveEvaluator.GetMoveQuality(solution,
            move,
            vehicles,
            dueTime, serviceTime,readyTime,
            demand, capacity,
            coordinates, fleetUsageFactor,
            timeFactor, distanceFactor,
            overloadPenalty, tardinessPenalty,
            distanceMatrixParameter,useDistanceMatrix).Quality;

          evaluatedSolutions++;
          if (moveQuality < quality || quality == -1) {
            quality = moveQuality;
            bestMove = move;
          }
        }
        if (bestMove != null) 
          AlbaLambdaInterchangeMoveMaker.Apply(solution, bestMove);
      }
    }

    public override IOperation Apply() {
      int maxIterations = MaximumIterationsParameter.ActualValue.Value;
      ValueLookupParameter<DoubleMatrix> distanceMatrix = new ValueLookupParameter<DoubleMatrix>("DistanceMatrix", problem.DistanceMatrix);

      AlbaEncoding solution = null;

      if (VRPToursParameter.ActualValue is AlbaEncoding)
        solution = VRPToursParameter.ActualValue as AlbaEncoding;
      else
        VRPToursParameter.ActualValue = solution = AlbaEncoding.ConvertFrom(VRPToursParameter.ActualValue, problem.VehiclesParameter.Value.Value,
        distanceMatrix);

      int lambda = LambdaParameter.Value.Value;
      int samples = SampleSizeParameter.Value.Value;
      IRandom random = RandomParameter.ActualValue;

      double quality = QualityParameter.ActualValue.Value;
      int evaluatedSolutions;

      Apply(solution, maxIterations, lambda, samples, random, ref quality, out evaluatedSolutions,
        problem.DistanceMatrix, problem.Vehicles, problem.DueTime, problem.ServiceTime,
        problem.ReadyTime, problem.Demand, problem.Capacity, problem.Coordinates,
        problem.FleetUsageFactorParameter.Value, problem.TimeFactorParameter.Value,
        problem.DistanceFactorParameter.Value, problem.OverloadPenaltyParameter.Value,
        problem.TardinessPenaltyParameter.Value, problem.UseDistanceMatrix);

      EvaluatedSolutionsParameter.ActualValue.Value += evaluatedSolutions;
      QualityParameter.ActualValue.Value = quality;

      return base.Apply();
    }
  }
}