Dual Pane File Manager

using System;
using System.Collections;
using System.Runtime.InteropServices;
using System.Text;
using System.Windows.Forms;
using JGLibrary;

namespace JGFSControls
{
	/// <summary>
	/// Specialist ListView sorter for JSysListViewFS
	/// </summary>
	internal class JListViewSorterFS : IComparer
	{
		private int m_SortColumn;
		private ListView m_ParentListView;
		private SortOrder m_SortOrder;

		internal JListViewSorterFS(ListView parentListView, int sortColumn, SortOrder sortOrder)
		{
			this.m_ParentListView = parentListView;
			m_SortColumn = sortColumn;
			this.m_SortOrder = sortOrder;
		}

		public int Compare(object ob1, object ob2)
		{
			int compareResult = 0;

			JListViewItemFS lvItem1 = (JListViewItemFS)ob1;
			JListViewItemFS lvItem2 = (JListViewItemFS)ob2;

			string str1 = "", str2 = "";

			//	If not detail view then use Name
			if (this.m_ParentListView.View != View.Details)
			{
				str1 = lvItem1.Text;
				str2 = lvItem2.Text;
				compareResult = String.Compare(str1, str2);
			}
			else
			{
				string strColumnName = this.m_ParentListView.Columns[m_SortColumn].Text;

				//	SortName has a prefix to ensure we keep files/folders separate
				if (this.m_SortColumn == 0)
				{
					compareResult = String.Compare(lvItem1.SortName, lvItem2.SortName);
				}

				//	If we are sorting column 1 we want to use sizes - except for folders where we use names
				else if (this.m_SortColumn == 1)
				{
					if (lvItem1.ObjectType == ObjectTypes.FOLDER || lvItem2.ObjectType == ObjectTypes.FOLDER)
					{
						compareResult = String.Compare(lvItem1.Text, lvItem2.Text);
					}
					else
					{
						if (lvItem1.Size > lvItem2.Size)
							compareResult = 1;
						else if (lvItem1.Size < lvItem2.Size)
							compareResult = -1;
						else
							compareResult = 0;
					}
				}

				//	If we are sorting column 2 we want to use dates - but separate folders
				else if (this.m_SortColumn == 2)
				{
					if (lvItem1.ObjectType == ObjectTypes.FOLDER && lvItem2.ObjectType >= ObjectTypes.FILE)
						compareResult = -1;
					else if (lvItem1.ObjectType >= ObjectTypes.FILE && lvItem2.ObjectType == ObjectTypes.FOLDER)
						compareResult = 1;
					else
						compareResult = DateTime.Compare(lvItem1.LastWriteTime, lvItem2.LastWriteTime);
				}

				//	OK may be Attributes or File Type or File Notes
				//	Could have a separate SortName for each but is it worth it?
				else if (strColumnName == "File Type" || strColumnName == "Attributes" || strColumnName == "File Notes")
				{
					str1 = lvItem1.SubItems[m_SortColumn].Text;
					if (lvItem1.ObjectType == ObjectTypes.FOLDER)
						str1 = "0" + str1;
					else
						str1 = "1" + str1;

					str2 = lvItem2.SubItems[m_SortColumn].Text;
					if (lvItem2.ObjectType == ObjectTypes.FOLDER)
						str2 = "0" + str2;
					else
						str2 = "1" + str2;
					compareResult = String.Compare(str1, str2);
				}
			}
			// Determine whether the sort order is descending - if so Invert the value returned by Compare
			if (m_SortOrder == SortOrder.Descending)
				compareResult *= -1;
			return compareResult;
		}

		
		internal void SetSortIcon()
		{
			const int HDF_LEFT = 0x0000;
			const int HDF_RIGHT = 0x0001;
			const int HDF_CENTER = 0x0002;
			const int HDF_STRING = 0x4000;
			const int HDF_SORTUP = 0x0400;
			const int HDF_SORTDOWN = 0x0200;
			const int HDI_TEXT = 0x0002;
			const int HDI_FORMAT = 0x0004;

			//	NB Only works in XP and later!
			const int HDM_FIRST = 0x1200;
			//	const int HDM_SETITEM = (HDM_FIRST + 4);
			//	Oooh Unicode in x64?
			const int HDM_SETITEMW = (HDM_FIRST + 12);
			const int LVM_GETHEADER = 4127;

			HDITEM hd;
			int intCount;

			//	In a long operation there can be a problem getting the handle to the ImageList
			try
			{
				IntPtr ipHeader = (IntPtr)JDll.SendMessage(this.m_ParentListView.Handle, LVM_GETHEADER, 0, 0);

				//	Set/Clear the Appropriate Icon
				for (intCount = 0; intCount < this.m_ParentListView.Columns.Count; intCount++)
				{
					hd = new HDITEM();
					hd.mask = HDI_FORMAT | HDI_TEXT;
					hd.pszText = this.m_ParentListView.Columns[intCount].Text;

					//	Set icon
					if (intCount == this.m_SortColumn)
					{
						if (this.m_SortOrder == SortOrder.Ascending)
							hd.fmt |= HDF_SORTUP;
						else
							hd.fmt |= HDF_SORTDOWN;
					}
					else
					//	clear icon
					{
						hd.fmt &= ~(HDF_SORTDOWN | HDF_SORTUP);
					}

					hd.fmt |= HDF_STRING;

					if (this.m_ParentListView.Columns[intCount].TextAlign == HorizontalAlignment.Left)
						hd.fmt |= HDF_LEFT;
					else if (this.m_ParentListView.Columns[intCount].TextAlign == HorizontalAlignment.Right)
						hd.fmt |= HDF_RIGHT;
					else
						hd.fmt |= HDF_CENTER;
					JDll.SendMessage(ipHeader, HDM_SETITEMW, intCount, ref hd);
				}
			}
			catch
			{
			}
		}

	}
}