#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;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;

namespace HeuristicLab.DataImporter.Data.Model {
  [StorableClass]
  public class DoubleColumn : ColumnBase {
    [Storable]
    private List<double?> values;

    [StorableConstructor]
    protected DoubleColumn(bool deserializing) : base(deserializing) { }

    public DoubleColumn(string columnName)
      : base(columnName) {
      this.values = new List<double?>();
    }

    public DoubleColumn(string columnName, int capacity)
      : this(columnName) {
      this.values.Capacity = capacity;
    }

    public override Type DataType {
      get { return typeof(double?); }
    }

    public override string ToString() {
      return base.ToString() + " <Double>";
    }

    protected override IList Values {
      get { return this.values; }
    }

    public override void AddValue(IComparable value) {
      this.values.Add((double?)value);
    }

    public override void AddValueOrNull(IComparable value) {
      this.values.Add(ConvertToDouble(value));
    }

    public override void InsertValue(int position, IComparable value) {
      this.values.Insert(position, (double?)value);
    }

    public override void ChangeValue(int position, IComparable value) {
      this.values[position] = (double?)value;
    }

    public override void ChangeValueOrNull(int position, IComparable value) {
      this.values[position] = ConvertToDouble(value);
    }

    public override void ChangeValueOrLeaveOldValue(int position, IComparable value) {
      if (value == null)
        this.values[position] = null;
      else {
        double? val = ConvertToDouble(value);
        if (val != null)
          this.values[position] = val;
      }
    }

    private double? ConvertToDouble(IComparable value) {
      double? val = null;
      double test;
      if (value != null) {
        if (value is DateTime)
          val = double.Parse(((DateTime)value).ToString("yyyyMMddHHmmss"));
        else if (value is string) {
          string s = value.ToString();
          if (s.StartsWith("."))
            s = s.Insert(0, "0");
          else if (s.StartsWith("-."))
            s = s.Insert(1, "0");
          CultureInfo culture = CultureInfo.CurrentCulture;
          if (s.Contains('.'))
            culture = CultureInfo.InvariantCulture;
          if (double.TryParse(s, NumberStyles.Any, culture, out test))
            val = test;
        } else if (value is double)
          val = (double)value;
      }
      return val;
    }

    public double? Mean {
      get {
        double sum = 0;
        int cnt = 0;
        for (int i = 0; i < this.values.Count; i++) {
          if (this.values[i] != null) {
            sum += (double)this.values[i];
            cnt++;
          }
        }
        if (cnt != 0)
          return sum / cnt;
        else
          return null;
      }
    }

    public double? StandardDeviation {
      get {
        double? mean = Mean;
        double sum = 0;
        if (mean == null)
          return null;

        for (int i = 0; i < this.values.Count; i++) {
          if (values[i] == null)
            continue;
          sum += Math.Pow((double)(values[i] - mean), 2.0);
        }
        return Math.Sqrt(sum / NonNullValuesCount);
      }
    }

    public double? Median {
      get {
        return GetMedian(0, this.TotalValuesCount);
      }
    }

    public double? GetMedian(int startIndex, int endIndex) {
      List<double?> sortedValues = values.GetRange(startIndex, endIndex - startIndex).Where(x => x != null).ToList(); ;
      if (sortedValues.Count == 0)
        return null;

      sortedValues.Sort();
      if (sortedValues.Count % 2 == 0)
        return (sortedValues[sortedValues.Count / 2] + sortedValues[sortedValues.Count / 2 - 1]) / 2;
      else
        return sortedValues[sortedValues.Count / 2];
    }

    public override ColumnBase CreateCopyOfColumnWithoutValues() {
      return CreateCopyOfColumnWithoutValues(this.values.Capacity);
    }

    public override ColumnBase CreateCopyOfColumnWithoutValues(int capacity) {
      return new DoubleColumn(this.Name, capacity);
    }
  }
}