/******************************************************************************
 * Class for comparing listview items in general on the selected column.
 * Written by John Cole starting October 12, 2010.
 ******************************************************************************/
using System;
using System.Collections.Generic;
using System.Collections;
using System.ComponentModel;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace Compare
  {
  public class LvComparer : IComparer
    {
    private int col;
    private SortOrder _order;
    public LvComparer()
      {
      col = 0;
      }

    public LvComparer(int pCol)
      {
      col = pCol;
      }

    /**************************************************************************
     * Function called by the ListView to compare two items.  Although the
     * declared type is "object," they are really ListViewItems.
     **************************************************************************/
    public int Compare(object l1, object l2)
      {
      int retVal = -1;
      // Make sure we actually have in the items the columns being compared.
      if (((ListViewItem)l1).SubItems.Count > col && ((ListViewItem)l2).SubItems.Count > col)
        {
        // If the text is right-aligned, this is a numeric column and must be
        // compared as decimal.
        if (((ListViewItem)l1).ListView.Columns[col].TextAlign == HorizontalAlignment.Right)
          {
          Decimal d1, d2;
          if (!decimal.TryParse(((ListViewItem)l1).SubItems[col].Text.Replace(",", "").Replace("$", ""), out d1))
            d1 = 0;
          if (!decimal.TryParse(((ListViewItem)l2).SubItems[col].Text.Replace(",", "").Replace("$", ""), out d2))
            d2 = 0;
          retVal = decimal.Compare(d1, d2);
          }
        else if (((ListViewItem)l1).ListView.Columns[col].Text.ToLower().Contains("date"))
          {
          DateTime dt1, dt2;
          dt1 = Convert.ToDateTime(((ListViewItem)l1).SubItems[col].Text);
          dt2 = Convert.ToDateTime(((ListViewItem)l2).SubItems[col].Text);
          retVal = DateTime.Compare(dt1, dt2);
          }
        else
          {
          // Compare any other alignment as string.
          retVal = string.Compare(((ListViewItem)l1).SubItems[col].Text, ((ListViewItem)l2).SubItems[col].Text);
          }
        }
      if (_order == SortOrder.Ascending)
        retVal = retVal * -1;
      return retVal;
      }

    public int SortColumn
      {
      set { col = value; }
      get { return col; }
      }

    public SortOrder Order
      {
      set { _order = value; }
      get { return _order; }
      }
    }
  }