#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 HeuristicLab.Common;
using HeuristicLab.Core;
using HeuristicLab.Data;
using HeuristicLab.Parameters;
using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;

namespace HeuristicLab.Problems.DataAnalysis.Symbolic {
  [StorableClass]
  [Item("Sliding Window GP Analyzer", "Base class for concrete sliding window GP analyzers.")]
  public abstract class SlidingWindowAnalyzer : SymbolicDataAnalysisAnalyzer {
    private const string ProblemDataParameterName = "ProblemData";
    private const string FitnessCalculationPartitionParameterName = "FitnessCalculationPartition";
    private const string ValidationPartitionParameterName = "ValidationPartition";
    private const string SlidingWindowSizeParameterName = "Sliding Window Size";
    private const string ValidationSlidingWindowSizeParameterName = "Validation Sliding Window Size";
    private const string SlidingWindowStepWidthParameterName = "Sliding Window Step Width";
    private const string InitialSlidingWindowParameterName = "Initial Sliding Window";
    private const string TerminateSlidingWindowParameterName = "TerminateSlidingWindow";

    #region parameter properties
    public IValueLookupParameter<IDataAnalysisProblemData> ProblemDataParameter {
      get { return (IValueLookupParameter<IDataAnalysisProblemData>)Parameters[ProblemDataParameterName]; }
    }
    public ILookupParameter<IntRange> FitnessCalculationPartitionParameter {
      get { return (ILookupParameter<IntRange>)Parameters[FitnessCalculationPartitionParameterName]; }
    }
    public ILookupParameter<IntRange> ValidationPartitionParameter {
      get { return (ILookupParameter<IntRange>)Parameters[ValidationPartitionParameterName]; }
    }
    public IFixedValueParameter<IntValue> SlidingWindowSizeParameter {
      get { return (IFixedValueParameter<IntValue>)Parameters[SlidingWindowSizeParameterName]; }
    }
    public IFixedValueParameter<IntValue> ValidationSlidingWindowSizeParameter {
      get { return (IFixedValueParameter<IntValue>)Parameters[ValidationSlidingWindowSizeParameterName]; }
    }
    public IFixedValueParameter<IntValue> SlidingWindowStepWidthParameter {
      get { return (IFixedValueParameter<IntValue>)Parameters[SlidingWindowStepWidthParameterName]; }
    }
    public IFixedValueParameter<IntRange> InitialSlidingWindowParameter {
      get { return (IFixedValueParameter<IntRange>)Parameters[InitialSlidingWindowParameterName]; }
    }
    public ILookupParameter<BoolValue> TerminateSlidingWindowParameter {
      get { return (ILookupParameter<BoolValue>)Parameters[TerminateSlidingWindowParameterName]; }
    }
    #endregion

    #region properties
    public override bool EnabledByDefault { get { return false; } }
    public IntValue SlidingWindowSize { get { return SlidingWindowSizeParameter.Value; } }
    public IntValue ValidiationSlidingWindowSize { get { return ValidationSlidingWindowSizeParameter.Value; } }
    public IntValue SlidingWindowStepWidth { get { return SlidingWindowStepWidthParameter.Value; } }
    public IntRange InitialSlidingWindow { get { return InitialSlidingWindowParameter.Value; } }
    #endregion


    [StorableConstructor]
    protected SlidingWindowAnalyzer(bool deserializing) : base(deserializing) { }
    protected SlidingWindowAnalyzer(SlidingWindowAnalyzer original, Cloner cloner)
      : base(original, cloner) { }

    protected SlidingWindowAnalyzer()
      : base() {
      Parameters.Add(new ValueLookupParameter<IDataAnalysisProblemData>(ProblemDataParameterName, "The problem data on which the symbolic data analysis solution should be evaluated."));
      Parameters.Add(new LookupParameter<IntRange>(FitnessCalculationPartitionParameterName, ""));
      Parameters.Add(new LookupParameter<IntRange>(ValidationPartitionParameterName, ""));
      Parameters.Add(new FixedValueParameter<IntValue>(SlidingWindowSizeParameterName, "", new IntValue(1)));
      Parameters.Add(new FixedValueParameter<IntValue>(ValidationSlidingWindowSizeParameterName, "", new IntValue(0)));
      Parameters.Add(new FixedValueParameter<IntValue>(SlidingWindowStepWidthParameterName, "", new IntValue(1)));
      Parameters.Add(new FixedValueParameter<IntRange>(InitialSlidingWindowParameterName, "", new IntRange(0, 1)));
      Parameters.Add(new LookupParameter<BoolValue>(TerminateSlidingWindowParameterName, ""));

      ProblemDataParameter.Hidden = true;
    }

    public override IOperation Apply() {
      //intialize sliding window
      if (FitnessCalculationPartitionParameter.ActualValue == null) {
        TerminateSlidingWindowParameter.ActualValue = new BoolValue(false);
        FitnessCalculationPartitionParameter.ActualValue = (IntRange)InitialSlidingWindow.Clone();
        ValidationPartitionParameter.ActualValue = new IntRange(InitialSlidingWindow.End, InitialSlidingWindow.End + ValidiationSlidingWindowSize.Value);
        return base.Apply();
      }

      if (!CheckForUpdate()) return base.Apply();

      //update necessary - move sliding window
      var fitnessPartition = (IntRange)FitnessCalculationPartitionParameter.ActualValue.Clone();
      if (fitnessPartition.End - fitnessPartition.Start == SlidingWindowSize.Value)
        fitnessPartition.Start += SlidingWindowStepWidth.Value;

      fitnessPartition.End += SlidingWindowStepWidth.Value;
      if (fitnessPartition.End - fitnessPartition.Start > SlidingWindowSize.Value)
        fitnessPartition.End = fitnessPartition.Start + SlidingWindowSize.Value;

      //check if update should be performed or if the algorithm should stop
      if (fitnessPartition.End > ProblemDataParameter.ActualValue.TrainingPartition.End)
        TerminateSlidingWindowParameter.ActualValue.Value = true;
      else {
        FitnessCalculationPartitionParameter.ActualValue.Start = fitnessPartition.Start;
        FitnessCalculationPartitionParameter.ActualValue.End = fitnessPartition.End;
        ValidationPartitionParameter.ActualValue.Start = fitnessPartition.End;
        ValidationPartitionParameter.ActualValue.End = ValidationPartitionParameter.ActualValue.Start + ValidiationSlidingWindowSize.Value;
      }

      return base.Apply();
    }

    protected abstract bool CheckForUpdate();
  }
}