#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2011 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.Persistence.Default.CompositeSerializers.Storable;
using HeuristicLab.DataImporter.Data.Model;
using System.Drawing;

namespace HeuristicLab.DataImporter.Command {
  public enum MatchOperation {
    Equal = 0,
    NotEqual = 1,
    Smaller = 2,
    Larger = 3,
  }

  [StorableClass]
  public abstract class SearchWithMatchOperationCommandBase : SearchCommandBase {
    private SearchWithMatchOperationCommandBase()
      : base(null, string.Empty, null) {
    }

    public SearchWithMatchOperationCommandBase(DataSet dataSet, string columnGroupName, int[] affectedColumns) :
      base(dataSet, columnGroupName, affectedColumns) {
    }

    [Storable]
    private MatchOperation matchOperation;
    public MatchOperation MatchOperation {
      get { return this.matchOperation; }
      set { this.matchOperation = value; }
    }

    protected Point[] GetAffectedCells() {
      List<Point> affectedCells = new List<Point>();
      Func<IComparable, IComparable, bool> compareFunction = this.GetCompareFunction(this.matchOperation);
      ColumnBase column;
      IComparable compareValue;
      IComparable value;

      for (int col = 0; col < AffectedColumns.Length; col++) {
        column = ColumnGroup.GetColumn(AffectedColumns[col]);
        compareValue = this.GetCompareValue(column, SearchValue);
        for (int row = 0; row < column.TotalValuesCount; row++) {
          value = column.GetValue(row);
          if (compareFunction(compareValue, value))
            affectedCells.Add(new Point(AffectedColumns[col], row));
        }
      }

      return affectedCells.ToArray();
    }

    private IComparable GetCompareValue(ColumnBase column, string searchValue) {
      if (string.IsNullOrEmpty(searchValue))
        return null;

      IComparable compareValue;
      if (column is DoubleColumn) {
        double v;
        if (!double.TryParse(SearchValue, out v)) throw new CommandExecutionException("Can't use value " + SearchValue + " to filter a DoubleColumn.", this);
        compareValue = v;
      } else if (column is DateTimeColumn) {
        DateTime d;
        if (!DateTime.TryParse(SearchValue, out d)) throw new CommandExecutionException("Can't use value " + SearchValue + " to filter a DateTimeColumn.", this);
        compareValue = d;
      } else if (column is StringColumn) {
        compareValue = SearchValue;
      } else throw new CommandExecutionException("Column type " + column.GetType() + " is not supported.", this);
      return compareValue;
    }

    private Func<IComparable, IComparable, bool> GetCompareFunction(MatchOperation matchOperation) {
      Func<IComparable, IComparable, bool> compareFunction;
      switch (matchOperation) {
        case MatchOperation.Equal:
          compareFunction = (left, right) => {
            if (left == null && right == null) return true;
            else if (left != null && right == null) return false;
            else if (left == null && right != null) return false;
            return left.CompareTo(right) == 0;
          };
          break;
        case MatchOperation.NotEqual:
          compareFunction = (left, right) => {
            if (left == null && right == null) return false;
            else if (left != null && right == null) return true;
            else if (left == null && right != null) return true;
            return left.CompareTo(right) != 0;
          };
          break;
        case MatchOperation.Smaller:
          compareFunction = (left, right) => {
            if (left == null && right == null) return false;
            else if (left != null && right == null) return false;
            else if (left == null && right != null) return false;
            return left.CompareTo(right) > 0;
          };
          break;
        case MatchOperation.Larger:
          compareFunction = (left, right) => { 
            if (left == null && right == null) return false;
            else if (left != null && right == null) return false;
            else if (left == null && right != null) return false;
            return left.CompareTo(right) < 0; };
          break;
        default:
          throw new ArgumentException("Undefined compare function.");
      }
      return compareFunction;
    }
  }
}