#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.Collections.Generic;
using System.Linq;
using System.Text;
using HeuristicLab.DataImporter.Data.CommandBase;
using HeuristicLab.DataImporter.Data.Model;
using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
using HeuristicLab.DataImporter.Data;
using HeuristicLab.DataImporter.Command.View;
using System.Windows.Forms;

namespace HeuristicLab.DataImporter.Command {
  [StorableClass]
  [ViewableCommandInfoAttribute("Change DateTimeColumn to DoubleColumn", 1, ColumnGroupState.DateTimeColumnSelected, "Time Series",
Position = 5, OptionsView = typeof(ChangeDateTimeCommandView))]
  public class ChangeDateTimeColumnToDoubleColumn : ColumnGroupCommandWithAffectedColumnsBase {
    private List<ColumnBase> newColumns;
    private List<ColumnBase> oldColumns;
    private List<int> positions;
    private ICollection<int> oldSortedColumnIndexes;
    private IEnumerable<SortOrder> oldSortOrder;

    private ChangeDateTimeColumnToDoubleColumn()
      : base(null, string.Empty, null) {
      newColumns = new List<ColumnBase>();
      oldColumns = new List<ColumnBase>();
      positions = new List<int>();
    }

    public ChangeDateTimeColumnToDoubleColumn(DataSet dataSet, string columnGroupName, int[] affectedColumns)
      : base(dataSet, columnGroupName, affectedColumns) {
      newColumns = new List<ColumnBase>();
      oldColumns = new List<ColumnBase>();
      positions = new List<int>();
    }

    public override string Description {
      get { return "Changes the date values to double by substracting from a given date and converting the result to the given unit."; }
    }

    [Storable]
    private DateTimeSpan frequency;
    public DateTimeSpan Frequency {
      get { return this.frequency; }
      set { this.frequency = value; }
    }

    [Storable]
    private DateTime startTime;
    public DateTime StartTime {
      get { return this.startTime; }
      set { this.startTime = value; }
    }

    public override void Execute() {
      base.Execute();
      oldSortOrder = ColumnGroup.SortOrdersForColumns.ToList();
      oldSortedColumnIndexes = new List<int>(ColumnGroup.SortedColumnIndexes);

      DateTimeColumn oldColumn;
      DoubleColumn newColumn;
      DateTime? value;
      double newValue;
      for (int j = 0; j < AffectedColumns.Length; j++) {
        oldColumn = (DateTimeColumn)ColumnGroup.Columns.ElementAt(AffectedColumns[j]);
        positions.Add(AffectedColumns[j]);
        oldColumns.Add(oldColumn);

        newColumn = new DoubleColumn(oldColumn.Name, oldColumn.TotalValuesCount);
        for (int i = 0; i < oldColumn.TotalValuesCount; i++) {
          value = (DateTime?)oldColumn.GetValue(i);
          if (!value.HasValue)
            newColumn.AddValue(null);
          else {
            TimeSpan elapsedTime = value.Value - startTime;
            if (frequency.Seconds == 1)
              newValue = elapsedTime.TotalSeconds;
            else if (frequency.Minutes == 1)
              newValue = elapsedTime.TotalMinutes;
            else if (frequency.Hours == 1)
              newValue = elapsedTime.TotalHours;
            else if (frequency.Days == 1)
              newValue = elapsedTime.TotalDays;
            else
              throw new CommandExecutionException("Unit for ChangeDateTimeColumnToDoubleColumn not correclty set.", this);
            newColumn.AddValue(newValue);
          }
        }
        newColumns.Add(newColumn);
      }

      for (int i = 0; i < positions.Count; i++)
        ColumnGroup.ReplaceColumn(positions[i], newColumns[i]);
      ColumnGroup.FireChanged();
    }

    public override void UndoExecute() {
      base.UndoExecute();

      for (int i = 0; i < positions.Count; i++)
        ColumnGroup.ReplaceColumn(positions[i], oldColumns[i]);

      ColumnGroup.SortOrdersForColumns = oldSortOrder;
      ColumnGroup.SortedColumnIndexes = oldSortedColumnIndexes;
      oldSortedColumnIndexes = null;
      oldSortOrder = null;
      oldColumns.Clear();
      newColumns.Clear();
      positions.Clear();

      ColumnGroup.FireChanged();
    }

  }
}