#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2008 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.Text;
using System.Windows.Forms;
using HeuristicLab.PluginInfrastructure;
using System.Net;
using System.ServiceModel;
using HeuristicLab.CEDMA.DB.Interfaces;
using HeuristicLab.CEDMA.DB;
using System.ServiceModel.Description;
using System.Linq;
using HeuristicLab.CEDMA.Core;
using HeuristicLab.GP.StructureIdentification;
using HeuristicLab.Data;
using HeuristicLab.Core;

namespace HeuristicLab.CEDMA.Server {
  public abstract class DispatcherBase :IDispatcher {
    public enum ModelComplexity { Low, Medium, High };
    public enum Algorithm { StandardGP };

    private IStore store;
    private ModelComplexity[] possibleComplexities = new ModelComplexity[] { ModelComplexity.Low, ModelComplexity.Medium, ModelComplexity.High };
    private Dictionary<LearningTask, Algorithm[]> possibleAlgorithms = new Dictionary<LearningTask, Algorithm[]>() {
      {LearningTask.Classification, new Algorithm[] {}},
      {LearningTask.Regression, new Algorithm[] { Algorithm.StandardGP }},
      {LearningTask.TimeSeries, new Algorithm[] { }}
    };

    public DispatcherBase(IStore store) {
      this.store = store;
    }

    public Execution GetNextJob() {
      // find and select a dataset
      var dataSetVar = new HeuristicLab.CEDMA.DB.Interfaces.Variable("DataSet");
      var dataSetQuery = new Statement[] {
        new Statement(dataSetVar, Ontology.PredicateInstanceOf, Ontology.TypeDataSet)
      };

      Entity[] datasets = store.Query("?DataSet <" + Ontology.PredicateInstanceOf.Uri + "> <" + Ontology.TypeDataSet.Uri + "> .")
        .Select(x => (Entity)x.Get("DataSet"))
        .ToArray();

      // no datasets => do nothing
      if (datasets.Length == 0) return null;

      Entity dataSetEntity = SelectDataSet(datasets);
      DataSet dataSet = new DataSet(store, dataSetEntity);

      int targetVariable = SelectTargetVariable(dataSet, dataSet.Problem.AllowedInputVariables.ToArray());
      Algorithm selectedAlgorithm = SelectAlgorithm(dataSet, targetVariable, possibleAlgorithms[dataSet.Problem.LearningTask]);
      string targetVariableName = dataSet.Problem.GetVariableName(targetVariable);
      ModelComplexity selectedComplexity = SelectComplexity(dataSet, targetVariable, selectedAlgorithm, possibleComplexities);

      Execution exec = CreateExecution(dataSet.Problem, targetVariable, selectedAlgorithm, selectedComplexity);
      if (exec != null) {
        exec.DataSetEntity = dataSetEntity;
        exec.TargetVariable = targetVariableName;
      }
      return exec;
    }

    public abstract Entity SelectDataSet(Entity[] datasets);
    public abstract int SelectTargetVariable(DataSet dataSet, int[] targetVariables);
    public abstract Algorithm SelectAlgorithm(DataSet dataSet, int targetVariable, Algorithm[] possibleAlgorithms);
    public abstract ModelComplexity SelectComplexity(DataSet dataSet, int targetVariable, Algorithm algorithm, ModelComplexity[] possibleComplexities);

    private Execution CreateExecution(Problem problem, int targetVariable, Algorithm algorithm, ModelComplexity complexity) {
      switch (algorithm) {
        case Algorithm.StandardGP: {
            return CreateStandardGpExecution(problem, targetVariable, complexity);
          }
        default: {
            return null;
          }
      }
    }

    private Execution CreateStandardGpExecution(Problem problem, int targetVariable, ModelComplexity complexity) {
      ProblemInjector probInjector = new ProblemInjector(problem);
      probInjector.TargetVariable = targetVariable;
      StandardGP sgp = new StandardGP();
      sgp.SetSeedRandomly = true;
      sgp.MaxGenerations = 2;
      sgp.PopulationSize = 100;
      sgp.Elites = 1;
      sgp.ProblemInjector = probInjector;

      int maxTreeHeight = 10;
      int maxTreeSize = 100;
      switch (complexity) {
        case ModelComplexity.Low: {
            maxTreeHeight = 5;
            maxTreeSize = 20;
            break;
          }
        case ModelComplexity.Medium: {
            maxTreeHeight = 10;
            maxTreeSize = 100;
            break;
          }
        case ModelComplexity.High: {
            maxTreeHeight = 12;
            maxTreeSize = 200;
            break;
          }
      }

      sgp.MaxTreeHeight = maxTreeHeight;
      sgp.MaxTreeSize = maxTreeSize;
      Execution exec = new Execution(sgp.Engine);
      exec.Description = "StandardGP - Complexity: " + complexity;
      return exec;
    }
  }
}