WPF Filename To Icon Converter

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.IO;
using System.Windows.Controls.Primitives;
using System.Diagnostics;

namespace QuickZip.Controls
{
    /// <summary>
    /// Interaction logic for SelectFolderTextBox.xaml
    /// </summary>
    public partial class SelectFolderTextBox : TextBox
    {
        Popup Popup { get { return this.Template.FindName("PART_Popup", this) as Popup; } }
        ListBox ItemList { get { return this.Template.FindName("PART_ItemList", this) as ListBox; } }
        //12-25-08 : Add Ghost image when picking from ItemList
        TextBlock TempVisual { get { return this.Template.FindName("PART_TempVisual", this) as TextBlock; } }
        ScrollViewer Host { get { return this.Template.FindName("PART_ContentHost", this) as ScrollViewer; } }
        UIElement TextBoxView { get { foreach (object o in LogicalTreeHelper.GetChildren(Host)) return o as UIElement; return null; } }

        private bool _loaded = false;
        string lastPath;

        public SelectFolderTextBox()
        {
            InitializeComponent();
        }

        

        public override void OnApplyTemplate()
        {
            base.OnApplyTemplate();
            _loaded = true;
            this.KeyDown += new KeyEventHandler(AutoCompleteTextBox_KeyDown);
            this.PreviewKeyDown += new KeyEventHandler(AutoCompleteTextBox_PreviewKeyDown);            
            ItemList.PreviewMouseDown += new MouseButtonEventHandler(ItemList_PreviewMouseDown);
            ItemList.KeyDown += new KeyEventHandler(ItemList_KeyDown);
            TempVisual.MouseDown += new MouseButtonEventHandler(TempVisual_MouseDown);                       
        }

        void TempVisual_MouseDown(object sender, MouseButtonEventArgs e)
        {
            string text = Text;
            ItemList.SelectedIndex = -1;
            Text = text;            
            Popup.IsOpen = false;
        }

        void AutoCompleteTextBox_PreviewKeyDown(object sender, KeyEventArgs e)
        {
            //12-25-08 - added PageDown Support
            if (ItemList.Items.Count > 0 && !(e.OriginalSource is ListBoxItem))
            switch (e.Key)
            {
                case Key.Up:
                case Key.Down:
                case Key.Prior: 
                case Key.Next:
                    ItemList.Focus();
                    ItemList.SelectedIndex = 0;
                    ListBoxItem lbi = ItemList.ItemContainerGenerator.ContainerFromIndex(ItemList.SelectedIndex) as ListBoxItem;
                    lbi.Focus();
                    e.Handled = true;
                    break;

            }
        }
   

        void ItemList_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.OriginalSource is ListBoxItem)
            {
                
                ListBoxItem tb = e.OriginalSource as ListBoxItem;
                
                e.Handled = true;
                switch (e.Key)
                {
                    case Key.Enter :
                        Text = (tb.Content as string);   updateSource(); break;
                    //12-25-08 - added "\" support when picking in list view
                    case Key.Oem5 :                          
                        Text = (tb.Content as string) + "\\"; 
                        break;
                    //12-25-08 - roll back if escape is pressed
                    case Key.Escape :
                        Text = lastPath.TrimEnd('\\') + "\\"; 
                        break;
                    default: e.Handled = false; break;
                }
                //12-25-08 - Force focus back the control after selected.
                if (e.Handled)
                {
                    Keyboard.Focus(this);
                    Popup.IsOpen = false;
                    this.Select(Text.Length, 0); //Select last char
                }
            }
        }


        void AutoCompleteTextBox_KeyDown(object sender, KeyEventArgs e)
        {           
                if (e.Key == Key.Enter)
                {
                    Popup.IsOpen = false;
                    updateSource();
                }
        }

        void updateSource()
        {
            if (this.GetBindingExpression(TextBox.TextProperty) != null)
                this.GetBindingExpression(TextBox.TextProperty).UpdateSource();
        }

        void ItemList_PreviewMouseDown(object sender, MouseButtonEventArgs e)
        {
            if (e.LeftButton == MouseButtonState.Pressed)
            {
                TextBlock tb = e.OriginalSource as TextBlock;
                if (tb != null)
                {
                    Text = tb.Text;
                    updateSource();
                    Popup.IsOpen = false;
                    e.Handled = true;
                }
            }
        }

        protected override void OnTextChanged(TextChangedEventArgs e)
        {
            if (_loaded)
            {                                
                    try
                    {
                        //if (lastPath != Path.GetDirectoryName(this.Text))
                        //if (textBox.Text.EndsWith("\\"))                        
                        {
                            lastPath = Path.GetDirectoryName(this.Text);
                            string[] paths = Lookup(this.Text);

                            ItemList.Items.Clear();
                            foreach (string path in paths)
                                if (!(String.Equals(path, this.Text, StringComparison.CurrentCultureIgnoreCase)))
                                    ItemList.Items.Add(path);
                        }                        
                            

                        Popup.IsOpen = ItemList.Items.Count > 0;

                        //ItemList.Items.Filter = p =>
                        //{
                        //    string path = p as string;
                        //    return path.StartsWith(this.Text, StringComparison.CurrentCultureIgnoreCase) &&
                        //        !(String.Equals(path, this.Text, StringComparison.CurrentCultureIgnoreCase));
                        //};
                    }
                    catch
                    {

                    }                
            }
        }


        private string[] Lookup(string path)
        {
            try
            {                    
                    if (Directory.Exists(Path.GetDirectoryName(path)))
                    {
                        DirectoryInfo lookupFolder = new DirectoryInfo(Path.GetDirectoryName(path));
                        if (lookupFolder != null)
                        {
                            DirectoryInfo[] AllItems = lookupFolder.GetDirectories();
                            return (from di in AllItems where di.FullName.StartsWith(path, StringComparison.CurrentCultureIgnoreCase) select di.FullName).ToArray();
                        }
                    }                    
            }
            catch (Exception ex)
            {                                
            }
            return new string[0];                
        }
    }    
}