// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
// Copyright (c) 2004-2006 Novell, Inc.
//
// Authors:
//	Jordi Mas i Hernandez, jordi@ximian.com
//	Mike Kestner  <mkestner@novell.com>
//	Daniel Nauck    (dna(at)mono-project(dot)de)

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Reflection;
using System.ComponentModel.Design;
using System.ComponentModel.Design.Serialization;
using System.Runtime.InteropServices;


namespace System.Windows.Forms
{
	[DefaultProperty("Items")]
	[DefaultEvent("SelectedIndexChanged")]
	[Designer ("System.Windows.Forms.Design.ComboBoxDesigner, " + Consts.AssemblySystem_Design, "System.ComponentModel.Design.IDesigner")]
#if NET_2_0
	[DefaultBindingProperty ("Text")]
	[ClassInterface (ClassInterfaceType.AutoDispatch)]
	[ComVisible(true)]
#endif
	public class ComboBox : ListControl
	{
		private DrawMode draw_mode = DrawMode.Normal;
		private ComboBoxStyle dropdown_style = (ComboBoxStyle)(-1);
		private int dropdown_width = -1;		
		private int selected_index = -1;
		internal ObjectCollection items = null;
		private bool suspend_ctrlupdate;
		private int maxdrop_items = 8;			
		private bool integral_height = true;
		private bool sorted;
		private int max_length;
		private ComboListBox listbox_ctrl;		
		private ComboTextBox textbox_ctrl;
		private bool process_textchanged_event = true;
		private bool item_height_specified = false;
		private int item_height;
		private int requested_height = -1;
		private Hashtable item_heights;
		private bool show_dropdown_button = false;
		private ButtonState button_state = ButtonState.Normal;
		private bool dropped_down;
		private Rectangle text_area;
		private Rectangle button_area;
		private Rectangle listbox_area;
		private const int button_width = 16;
#if NET_2_0
		private AutoCompleteStringCollection auto_complete_custom_source = null;
		private AutoCompleteMode auto_complete_mode = AutoCompleteMode.None;
		private AutoCompleteSource auto_complete_source = AutoCompleteSource.None;
#endif

		[ComVisible(true)]
		public class ChildAccessibleObject : AccessibleObject {

			public ChildAccessibleObject (ComboBox owner, IntPtr handle)
				: base (owner)
			{
			}

			public override string Name {
				get {
					return base.Name;
				}
			}
		}

		public ComboBox ()
		{
			items = new ObjectCollection (this);
			DropDownStyle = ComboBoxStyle.DropDown;
			item_height = FontHeight + 2;
			BackColor = ThemeEngine.Current.ColorWindow;
			border_style = BorderStyle.None;

			/* Events */
			MouseDown += new MouseEventHandler (OnMouseDownCB);
			MouseUp += new MouseEventHandler (OnMouseUpCB);
			MouseMove += new MouseEventHandler (OnMouseMoveCB);
			MouseWheel += new MouseEventHandler (OnMouseWheelCB);				
			KeyDown +=new KeyEventHandler(OnKeyDownCB);
		}

		#region events
		
		[Browsable (false)]
		[EditorBrowsable (EditorBrowsableState.Never)]
		public new event EventHandler BackgroundImageChanged {
			add { base.BackgroundImageChanged += value; }
			remove { base.BackgroundImageChanged -= value; }
		}

		static object DrawItemEvent = new object ();
		static object DropDownEvent = new object ();
		static object DropDownStyleChangedEvent = new object ();
		static object MeasureItemEvent = new object ();
		static object SelectedIndexChangedEvent = new object ();
		static object SelectionChangeCommittedEvent = new object ();

		public event DrawItemEventHandler DrawItem {
			add { Events.AddHandler (DrawItemEvent, value); }
			remove { Events.RemoveHandler (DrawItemEvent, value); }
		}

		public event EventHandler DropDown {
			add { Events.AddHandler (DropDownEvent, value); }
			remove { Events.RemoveHandler (DropDownEvent, value); }
		}

		public event EventHandler DropDownStyleChanged {
			add { Events.AddHandler (DropDownStyleChangedEvent, value); }
			remove { Events.RemoveHandler (DropDownStyleChangedEvent, value); }
		}

		public event MeasureItemEventHandler MeasureItem {
			add { Events.AddHandler (MeasureItemEvent, value); }
			remove { Events.RemoveHandler (MeasureItemEvent, value); }
		}
		
		[Browsable (false)]
		[EditorBrowsable (EditorBrowsableState.Never)]
		public new event PaintEventHandler Paint {
			add { base.Paint += value; }
			remove { base.Paint -= value; }
		}
		
		public event EventHandler SelectedIndexChanged {
			add { Events.AddHandler (SelectedIndexChangedEvent, value); }
			remove { Events.RemoveHandler (SelectedIndexChangedEvent, value); }
		}

		public event EventHandler SelectionChangeCommitted {
			add { Events.AddHandler (SelectionChangeCommittedEvent, value); }
			remove { Events.RemoveHandler (SelectionChangeCommittedEvent, value); }
		}

		#endregion Events

		#region Public Properties
#if NET_2_0
		[MonoTODO("AutoCompletion algorithm is currently not implemented.")]
		[DesignerSerializationVisibility (DesignerSerializationVisibility.Content)]
		[Browsable (true)]
		[EditorBrowsable (EditorBrowsableState.Always)]
		[Localizable (true)]
		[Editor ("System.Windows.Forms.Design.ListControlStringCollectionEditor, " + Consts.AssemblySystem_Design,
			 "System.Drawing.Design.UITypeEditor, " + Consts.AssemblySystem_Drawing)]
		public AutoCompleteStringCollection AutoCompleteCustomSource { 
			get {
				if(auto_complete_custom_source == null) {
					auto_complete_custom_source = new AutoCompleteStringCollection ();
					auto_complete_custom_source.CollectionChanged += new CollectionChangeEventHandler (OnAutoCompleteCustomSourceChanged);
				}
				return auto_complete_custom_source;
			}
			set {
				if(auto_complete_custom_source == value)
					return;

				if(auto_complete_custom_source != null) //remove eventhandler from old collection
					auto_complete_custom_source.CollectionChanged -= new CollectionChangeEventHandler (OnAutoCompleteCustomSourceChanged);

				auto_complete_custom_source = value;

				if(auto_complete_custom_source != null)
					auto_complete_custom_source.CollectionChanged += new CollectionChangeEventHandler (OnAutoCompleteCustomSourceChanged);
			}
		}

		[MonoTODO("AutoCompletion algorithm is currently not implemented.")]
		[Browsable (true)]
		[EditorBrowsable (EditorBrowsableState.Always)]
		[DefaultValue (AutoCompleteMode.None)]
		public AutoCompleteMode AutoCompleteMode {
			get { return auto_complete_mode; }
			set {
				if(auto_complete_mode == value)
					return;

				if((value < AutoCompleteMode.None) || (value > AutoCompleteMode.SuggestAppend))
					throw new InvalidEnumArgumentException (Locale.GetText ("Enum argument value '{0}' is not valid for AutoCompleteMode", value));

				auto_complete_mode = value;
			}
		}

		[MonoTODO("AutoCompletion algorithm is currently not implemented.")]
		[Browsable (true)]
		[EditorBrowsable (EditorBrowsableState.Always)]
		[DefaultValue (AutoCompleteSource.None)]
		public AutoCompleteSource AutoCompleteSource {
			get { return auto_complete_source; }
			set {
				if(auto_complete_source == value)
					return;

				if(!Enum.IsDefined (typeof (AutoCompleteSource), value))
					throw new InvalidEnumArgumentException (Locale.GetText ("Enum argument value '{0}' is not valid for AutoCompleteSource", value));

				auto_complete_source = value;
			}
		}
#endif
		public override Color BackColor {
			get { return base.BackColor; }
			set {
				if (base.BackColor == value)
					return;

    				base.BackColor = value;
				Refresh ();
			}
		}

		[Browsable (false)]
		[EditorBrowsable (EditorBrowsableState.Never)]
		public override Image BackgroundImage {
			get { return base.BackgroundImage; }
			set {
				if (base.BackgroundImage == value)
					return;

    				base.BackgroundImage = value;
				Refresh ();
			}
		}

		protected override CreateParams CreateParams {
			get { return base.CreateParams;}
		}

		protected override Size DefaultSize {
			get { return new Size (121, 21); }
		}

		[RefreshProperties(RefreshProperties.Repaint)]
		[DefaultValue (DrawMode.Normal)]
		public DrawMode DrawMode {
			get { return draw_mode; }

    			set {
				if (!Enum.IsDefined (typeof (DrawMode), value))
					throw new InvalidEnumArgumentException (string.Format("Enum argument value '{0}' is not valid for DrawMode", value));

				if (draw_mode == value)
					return;

				if (draw_mode == DrawMode.OwnerDrawVariable)
					item_heights = null;
    				draw_mode = value;
				if (draw_mode == DrawMode.OwnerDrawVariable)
					item_heights = new Hashtable ();
				Refresh ();
    			}
		}

		[DefaultValue (ComboBoxStyle.DropDown)]
		[RefreshProperties(RefreshProperties.Repaint)]
		public ComboBoxStyle DropDownStyle {
			get { return dropdown_style; }

    			set {
		
				if (!Enum.IsDefined (typeof (ComboBoxStyle), value))
					throw new InvalidEnumArgumentException (string.Format("Enum argument value '{0}' is not valid for ComboBoxStyle", value));

				if (dropdown_style == value)
					return;					

				SuspendLayout ();

				if (dropdown_style == ComboBoxStyle.Simple) {
					if (listbox_ctrl != null) {						
						Controls.RemoveImplicit (listbox_ctrl);
						listbox_ctrl.Dispose ();						
						listbox_ctrl = null;
					}
				}

				dropdown_style = value;					
				
				if (dropdown_style == ComboBoxStyle.DropDownList && textbox_ctrl != null) {
					Controls.RemoveImplicit (textbox_ctrl);
					textbox_ctrl.Dispose ();						
					textbox_ctrl = null;						
				}				

				if (dropdown_style == ComboBoxStyle.Simple) {
					show_dropdown_button = false;					
					
					CreateComboListBox ();

					if (IsHandleCreated) {
						Controls.AddImplicit (listbox_ctrl);
						listbox_ctrl.Visible = true;
					}
				} else {
					show_dropdown_button = true;
					button_state = ButtonState.Normal;
				}				
	
				if (dropdown_style != ComboBoxStyle.DropDownList && textbox_ctrl == null) {
					textbox_ctrl = new ComboTextBox (this);
					object selected_item = SelectedItem;
					if (selected_item != null)
						textbox_ctrl.Text = GetItemText (selected_item);
					textbox_ctrl.BorderStyle = BorderStyle.None;
					textbox_ctrl.TextChanged += new EventHandler (OnTextChangedEdit);
					textbox_ctrl.Click += new EventHandler (OnTextBoxClick);

					if (IsHandleCreated == true) {
						Controls.AddImplicit (textbox_ctrl);
					}
				}
				
				ResumeLayout ();
				OnDropDownStyleChanged (EventArgs.Empty);
    				
				LayoutComboBox ();
				UpdateComboBoxBounds ();
				Refresh ();
    			}
		}

		public int DropDownWidth {
			get { 
				if (dropdown_width == -1)
					return Width;
					
				return dropdown_width; 
			}
			set {
				if (dropdown_width == value)
					return;
					
				if (value < 1)
#if NET_2_0
					throw new ArgumentOutOfRangeException ("DropDownWidth",
						"The DropDownWidth value is less than one.");
#else
					throw new ArgumentException ("The DropDownWidth value is less than one.");
#endif

				dropdown_width = value;
			}
		}
		
		[Browsable (false)]
		[DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
		public bool DroppedDown {
			get { 
				if (dropdown_style == ComboBoxStyle.Simple)
					return true;
				
				return dropped_down;
			}
			set {
				if (dropdown_style == ComboBoxStyle.Simple || dropped_down == value)
					return;
					
				if (value) 
					DropDownListBox ();
				else
					listbox_ctrl.Hide ();
			}
		}		

		public override bool Focused {
			get { return base.Focused; }
		}

		public override Color ForeColor {
			get { return base.ForeColor; }
			set {
				if (base.ForeColor == value)
					return;

    				base.ForeColor = value;
				Refresh ();
			}
		}

		[DefaultValue (true)]
		[Localizable (true)]		
		public bool IntegralHeight {
			get { return integral_height; }
			set {
				if (integral_height == value)
					return;

    				integral_height = value;
				UpdateComboBoxBounds ();
    				Refresh ();
			}
		}

		[Localizable (true)]
		public int ItemHeight {
			get {
				if (item_height == -1) {
					SizeF sz = DeviceContext.MeasureString ("The quick brown Fox", Font);
					item_height = (int) sz.Height;
				}
				return item_height;
			}
			set {
				if (value < 1)
#if NET_2_0
					throw new ArgumentOutOfRangeException ("ItemHeight",
						"The item height value is less than one.");
#else
					throw new ArgumentException ("The item height value is less than one.");
#endif

				item_height_specified = true;
				item_height = value;
				if (IntegralHeight)
					UpdateComboBoxBounds ();
				LayoutComboBox ();
				Refresh ();
			}
		}

		[DesignerSerializationVisibility (DesignerSerializationVisibility.Content)]
		[Localizable (true)]
		[Editor ("System.Windows.Forms.Design.ListControlStringCollectionEditor, " + Consts.AssemblySystem_Design, typeof (System.Drawing.Design.UITypeEditor))]
#if NET_2_0
		[MergableProperty (false)]
#endif
		public ComboBox.ObjectCollection Items {
			get { return items; }
		}

		[DefaultValue (8)]
		[Localizable (true)]
		public int MaxDropDownItems {
			get { return maxdrop_items; }
			set {
				if (maxdrop_items == value)
					return;

    				maxdrop_items = value;
			}
		}

		[DefaultValue (0)]
		[Localizable (true)]
		public int MaxLength {
			get { return max_length; }
			set {
				if (max_length == value)
					return;

				max_length = value;
				
				if (dropdown_style != ComboBoxStyle.DropDownList) {
					
					if (value < 0) {
						value = 0;
					}
					
					textbox_ctrl.MaxLength = value;
				}			
			}
		}

		[DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
		[Browsable (false)]		
		public int PreferredHeight {
			get {
				return ItemHeight + 5;
			}
		}

		[Browsable (false)]
		[DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
		public override int SelectedIndex {
			get { return selected_index; }
			set {
				if (selected_index == value)
					return;

				if (value <= -2 || value >= Items.Count)
					throw new ArgumentOutOfRangeException ("Index of out range");
    				selected_index = value;

    				if (dropdown_style != ComboBoxStyle.DropDownList) {
					if (value == -1)
						SetControlText("");
					else
						SetControlText (GetItemText (Items [value]));
    				}

				if (DropDownStyle == ComboBoxStyle.DropDownList)
    					Invalidate ();

				if (listbox_ctrl != null)
					listbox_ctrl.HighlightedIndex = value;

				OnSelectedValueChanged (new EventArgs ());
				OnSelectedIndexChanged (new EventArgs ());
				OnSelectedItemChanged (new EventArgs ());
			}
		}

		[Browsable (false)]
		[DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
		[Bindable(true)]
		public object SelectedItem {
			get { return selected_index == -1 ? null : Items [selected_index]; }
			set {				
				object item = selected_index == -1 ? null : Items [selected_index];
				if (item == value)
					return;

				SelectedIndex = Items.IndexOf (value);
			}
		}
		
		[Browsable (false)]
		[DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
		public string SelectedText {
			get {
				if (dropdown_style == ComboBoxStyle.DropDownList)
					return "";
					
				return textbox_ctrl.SelectedText;
			}
			set {
				if (dropdown_style == ComboBoxStyle.DropDownList)
					return;
				
				textbox_ctrl.SelectedText = value;
			}
		}

		[Browsable (false)]
		[DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
		public int SelectionLength {
			get {
				if (dropdown_style == ComboBoxStyle.DropDownList) 
					return 0;
				
				int result = textbox_ctrl.SelectionLength;
				return result == -1 ? 0 : result;
			}
			set {
				if (dropdown_style == ComboBoxStyle.DropDownList) 
					return;
					
				if (textbox_ctrl.SelectionLength == value)
					return;
					
				textbox_ctrl.SelectionLength = value;
			}
		}

		[Browsable (false)]
		[DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
		public int SelectionStart {
			get { 
				if (dropdown_style == ComboBoxStyle.DropDownList) 
					return 0; 					
				
				return textbox_ctrl.SelectionStart;				
			}
			set {
				if (dropdown_style == ComboBoxStyle.DropDownList) 
					return;
				
				if (textbox_ctrl.SelectionStart == value)
					return;					
				
				textbox_ctrl.SelectionStart = value;
			}
		}

		[DefaultValue (false)]
		public bool Sorted {
			get { return sorted; }

    			set {
				if (sorted == value)
					return;

    				sorted = value;
				SelectedIndex = -1;
				if (sorted) {
					Items.Sort ();
					LayoutComboBox ();
				}
    			}
    		}

		[Bindable (true)]
		[Localizable (true)]
		public override string Text {
			get {
				if (dropdown_style != ComboBoxStyle.DropDownList) {
					if (textbox_ctrl != null) {
						return textbox_ctrl.Text;
					}
				}

				if (SelectedItem != null)
					return GetItemText (SelectedItem);
								
				return base.Text;				
			}
			set {				
				if (value == null) {
					SelectedIndex = -1;
					return;
				}
				
				int index = FindString (value);
				
				if (index != -1) {
					SelectedIndex = index;
					return;					
				}
				
				if (dropdown_style != ComboBoxStyle.DropDownList)
					textbox_ctrl.Text = GetItemText (value);
			}
		}

		#endregion Public Properties

		#region Public Methods
#if NET_2_0
		[Obsolete ("This method has been deprecated")]
#endif
		protected virtual void AddItemsCore (object[] value)
		{
			
		}

		public void BeginUpdate ()
		{
			suspend_ctrlupdate = true;
		}

		protected override void Dispose (bool disposing)
		{						
			if (disposing) {
				if (listbox_ctrl != null) {
					listbox_ctrl.Dispose ();
					Controls.RemoveImplicit (listbox_ctrl);
					listbox_ctrl = null;
				}			
			
				if (textbox_ctrl != null) {
					Controls.RemoveImplicit (textbox_ctrl);
					textbox_ctrl.Dispose ();
					textbox_ctrl = null;
				}			
			}
			
			base.Dispose (disposing);
		}

		public void EndUpdate ()
		{
			suspend_ctrlupdate = false;
			UpdatedItems ();
			Refresh ();
		}

		public int FindString (string s)
		{
			return FindString (s, -1);
		}

		public int FindString (string s, int startIndex)
		{
			if (Items.Count == 0) 
				return -1; // No exception throwing if empty

			if (startIndex < -1 || startIndex >= Items.Count - 1)
				throw new  ArgumentOutOfRangeException ("Index of out range");

			startIndex++;
			for (int i = startIndex; i < Items.Count; i++) {
				if ((GetItemText (Items[i])).StartsWith (s))
					return i;
			}

			return -1;
		}

		public int FindStringExact (string s)
		{
			return FindStringExact (s, -1);
		}

		public int FindStringExact (string s, int startIndex)
		{
			if (Items.Count == 0) 
				return -1; // No exception throwing if empty

#if NET_2_0
			if (startIndex < -1 || startIndex >= Items.Count)
#else
			if (startIndex < -1 || startIndex >= Items.Count - 1)
#endif
				throw new ArgumentOutOfRangeException ("Index of out range");

			startIndex++;
			for (int i = startIndex; i < Items.Count; i++) {
				if ((GetItemText (Items[i])).Equals (s))
					return i;
			}

			return -1;
		}

		public int GetItemHeight (int index)
		{	
			if (DrawMode == DrawMode.OwnerDrawVariable && IsHandleCreated) {

				if (index < 0 || index >= Items.Count )
					throw new ArgumentOutOfRangeException ("The item height value is less than zero");
				
				object item = Items [index];
				if (item_heights.Contains (item))
					return (int) item_heights [item];
				
				MeasureItemEventArgs args = new MeasureItemEventArgs (DeviceContext, index, ItemHeight);
				OnMeasureItem (args);
				item_heights [item] = args.ItemHeight;
				return args.ItemHeight;
			}

			return ItemHeight;
		}

		protected override bool IsInputKey (Keys keyData)
		{
			switch (keyData) {
			case Keys.Up:
			case Keys.Down:
			case Keys.Left:
			case Keys.Right:
			case Keys.PageUp:
			case Keys.PageDown:			
				return true;
			
			default:					
				return false;
			}
		}

		protected override void OnBackColorChanged (EventArgs e)
		{
			base.OnBackColorChanged (e);
		}

		protected override void OnDataSourceChanged (EventArgs e)
		{
			base.OnDataSourceChanged (e);
			BindDataItems ();
			
			if (DataSource == null || DataManager == null) {
				SelectedIndex = -1;
			} 
			else {
				SelectedIndex = DataManager.Position;
			}
		}

		protected override void OnDisplayMemberChanged (EventArgs e)
		{
			base.OnDisplayMemberChanged (e);

			if (DataManager == null || !IsHandleCreated)
			       return;

			BindDataItems ();
			SelectedIndex = DataManager.Position;
		}

		protected virtual void OnDrawItem (DrawItemEventArgs e)
		{
			switch (DrawMode) {
			case DrawMode.OwnerDrawFixed:
			case DrawMode.OwnerDrawVariable:
				DrawItemEventHandler eh = (DrawItemEventHandler)(Events [DrawItemEvent]);
				if (eh != null)
					eh (this, e);
				break;
			default:
				ThemeEngine.Current.DrawComboBoxItem (this, e);
				break;
			}
		}		

		protected virtual void OnDropDown (EventArgs e)
		{
			EventHandler eh = (EventHandler)(Events [DropDownEvent]);
			if (eh != null)
				eh (this, e);
		}

		protected virtual void OnDropDownStyleChanged (EventArgs e)
		{
			EventHandler eh = (EventHandler)(Events [DropDownStyleChangedEvent]);
			if (eh != null)
				eh (this, e);
		}

		protected override void OnFontChanged (EventArgs e)
		{
			base.OnFontChanged (e);

			if (textbox_ctrl != null)
				textbox_ctrl.Font = Font;
			
			if (!item_height_specified) {
				SizeF sz = DeviceContext.MeasureString ("The quick brown Fox", Font);
				item_height = (int) sz.Height;
			}

			if (IntegralHeight)
				UpdateComboBoxBounds ();

			LayoutComboBox ();
		}

		protected override void OnForeColorChanged (EventArgs e)
		{
			base.OnForeColorChanged (e);
		}

		[EditorBrowsable(EditorBrowsableState.Advanced)]		
		protected override void OnGotFocus (EventArgs e)
		{
			if (dropdown_style == ComboBoxStyle.DropDownList) {
				// We draw DDL styles manually, so they require a
				// refresh to have their selection drawn
				Invalidate ();
			}
			
			if (textbox_ctrl != null) {
				textbox_ctrl.SetSelectable (false);
				textbox_ctrl.ActivateCaret (true);
				textbox_ctrl.ShowSelection = true;
				textbox_ctrl.SelectAll ();
			}

			base.OnGotFocus (e);
		}

		[EditorBrowsable(EditorBrowsableState.Advanced)]		
		protected override void OnLostFocus (EventArgs e)
		{
			if (dropdown_style == ComboBoxStyle.DropDownList) {
				// We draw DDL styles manually, so they require a
				// refresh to have their selection drawn
				Invalidate ();
			}

			if (listbox_ctrl != null && dropped_down) {
				listbox_ctrl.HideWindow ();
			}

			if (textbox_ctrl != null) {
				textbox_ctrl.SetSelectable (true);
				textbox_ctrl.ActivateCaret (false);
				textbox_ctrl.ShowSelection = false;
			}

			base.OnLostFocus (e);
		}

		protected override void OnHandleCreated (EventArgs e)
		{
			base.OnHandleCreated (e);

			if (listbox_ctrl != null) {
				Controls.AddImplicit (listbox_ctrl);
				listbox_ctrl.Visible = true;
			}

			if (textbox_ctrl != null)
				Controls.AddImplicit (textbox_ctrl);

			LayoutComboBox ();
		}

		protected override void OnHandleDestroyed (EventArgs e)
		{
			base.OnHandleDestroyed (e);
		}

		protected override void OnKeyPress (KeyPressEventArgs e)
		{
			// int index = FindStringCaseInsensitive (e.KeyChar.ToString (), SelectedIndex);
			//if (index != -1)
			//	SelectedIndex = index;

			base.OnKeyPress (e);
		}

		protected virtual void OnMeasureItem (MeasureItemEventArgs e)
		{
			MeasureItemEventHandler eh = (MeasureItemEventHandler)(Events [MeasureItemEvent]);
			if (eh != null)
				eh (this, e);
		}

		protected override void OnParentBackColorChanged (EventArgs e)
		{
			base.OnParentBackColorChanged (e);
		}

		protected override void OnResize (EventArgs e)
		{			
			LayoutComboBox ();
			if (listbox_ctrl != null)
				listbox_ctrl.CalcListBoxArea ();
		}

		protected override void OnSelectedIndexChanged (EventArgs e)
		{
			base.OnSelectedIndexChanged (e);

			EventHandler eh = (EventHandler)(Events [SelectedIndexChangedEvent]);
			if (eh != null)
				eh (this, e);
		}

		protected virtual void OnSelectedItemChanged (EventArgs e)
		{
			
		}

		protected override void OnSelectedValueChanged (EventArgs e)
		{
			base.OnSelectedValueChanged (e);
		}

		protected virtual void OnSelectionChangeCommitted (EventArgs e)
		{
			EventHandler eh = (EventHandler)(Events [SelectionChangeCommittedEvent]);
			if (eh != null)
				eh (this, e);
		}

		protected override void RefreshItem (int index)
		{
			if (index < 0 || index >= Items.Count)
				throw new ArgumentOutOfRangeException ("Index of out range");
				
			if (draw_mode == DrawMode.OwnerDrawVariable)
				item_heights.Remove (Items [index]);
		}

#if NET_2_0
		protected override bool ProcessKeyEventArgs (ref Message m)
		{
			return base.ProcessKeyEventArgs (ref m);
		}

		[EditorBrowsable (EditorBrowsableState.Advanced)]
		protected override void OnKeyDown (KeyEventArgs e)
		{
			base.OnKeyDown (e);
		}

		[EditorBrowsable (EditorBrowsableState.Advanced)]
		protected override void OnValidating (CancelEventArgs e)
		{
			base.OnValidating (e);
		}

		[EditorBrowsable (EditorBrowsableState.Advanced)]
		protected override void OnTextChanged (EventArgs e)
		{
			base.OnTextChanged (e);
		}

		protected override void OnMouseLeave (EventArgs e)
		{
			base.OnMouseLeave (e);
		}
		
		protected override void OnMouseEnter (EventArgs e)
		{
			base.OnMouseEnter (e);
		}
#endif

		public void Select (int start, int length)
		{
			if (start < 0)
				throw new ArgumentException ("Start cannot be less than zero");
				
			if (length < 0)
				throw new ArgumentException ("length cannot be less than zero");
				
			if (dropdown_style == ComboBoxStyle.DropDownList)
				return;

			textbox_ctrl.Select (start, length);
		}

		public void SelectAll ()
		{
			if (dropdown_style == ComboBoxStyle.DropDownList)
				return;

			if (textbox_ctrl != null) {
				textbox_ctrl.ShowSelection = true;
				textbox_ctrl.SelectAll ();
			}
		}		

		protected override void SetBoundsCore (int x, int y, int width, int height, BoundsSpecified specified)
		{			
			if ((specified & BoundsSpecified.Height) != 0) {
				requested_height = height;

				if (DropDownStyle == ComboBoxStyle.Simple && height > PreferredHeight) {
					if (IntegralHeight) {
						int border = ThemeEngine.Current.Border3DSize.Height;
						int lb_height = height - PreferredHeight - 2;
						if (lb_height - 2 * border > ItemHeight) {
							int partial = (lb_height - 2 * border) % ItemHeight;
							height -= partial;
						} else
							height = PreferredHeight;
					}
				} else
					height = PreferredHeight;
			}

			base.SetBoundsCore (x, y, width, height, specified);
		}

		protected override void SetItemCore (int index, object value)
		{
			if (index < 0 || index >= Items.Count)
				return;

			Items[index] = value;
		}

		protected override void SetItemsCore (IList value)
		{
			BeginUpdate ();
			try {
				Items.Clear ();
				Items.AddRange (value);
			} finally {
                               EndUpdate ();
			}
		}

		public override string ToString ()
		{
			return base.ToString () + ", Items.Count:" + Items.Count;
		}

		protected override void WndProc (ref Message m)
		{
			switch ((Msg) m.Msg) {
			case Msg.WM_KEYUP:
			case Msg.WM_KEYDOWN:
				Keys keys = (Keys) m.WParam.ToInt32 ();
				if (keys == Keys.Up || keys == Keys.Down)
					break;
				goto case Msg.WM_CHAR;
			case Msg.WM_CHAR:
				if (textbox_ctrl != null)
					XplatUI.SendMessage (textbox_ctrl.Handle, (Msg) m.Msg, m.WParam, m.LParam);
				break;
			case Msg.WM_MOUSE_LEAVE:
				Point location = PointToClient (Control.MousePosition);
				if (ClientRectangle.Contains (location))
					return;
				break;
			default:
				break;
			}
			base.WndProc (ref m);
		}

		#endregion Public Methods

		#region Private Methods
#if NET_2_0
		void OnAutoCompleteCustomSourceChanged(object sender, CollectionChangeEventArgs e) {
			if(auto_complete_source == AutoCompleteSource.CustomSource) {
				//FIXME: handle add, remove and refresh events in AutoComplete algorithm.
			}
		}
#endif

		internal override bool InternalCapture {
			get { return Capture; }
			set {}
		}
		
		void LayoutComboBox ()
		{			
			int border = ThemeEngine.Current.Border3DSize.Width;

			text_area = ClientRectangle;
			text_area.Height = PreferredHeight;
			
			listbox_area = ClientRectangle;
			listbox_area.Y = text_area.Bottom + 3;
			listbox_area.Height -= (text_area.Height + 2);

			Rectangle prev_button_area = button_area;

			if (DropDownStyle == ComboBoxStyle.Simple)
				button_area = Rectangle.Empty;
			else {
				button_area = text_area;
			       	button_area.X = text_area.Right - button_width - border;
			       	button_area.Y = text_area.Y + border;
				button_area.Width = button_width;
				button_area.Height = text_area.Height - 2 * border;
			}

			if (button_area != prev_button_area) {
				prev_button_area.Y -= border;
				prev_button_area.Width += border;
				prev_button_area.Height += 2 * border;
				Invalidate (prev_button_area);
				Invalidate (button_area);
			}

			if (textbox_ctrl != null) {
				textbox_ctrl.Location = new Point (text_area.X + border, text_area.Y + border);
				textbox_ctrl.Width = text_area.Width - button_area.Width - border * 2;
				textbox_ctrl.Height = text_area.Height - border * 2;
			}

			if (listbox_ctrl != null && dropdown_style == ComboBoxStyle.Simple) {
				listbox_ctrl.Location = listbox_area.Location;
				listbox_ctrl.CalcListBoxArea ();
			}
		}

		private void CreateComboListBox ()
		{			
			listbox_ctrl = new ComboListBox (this);			
			listbox_ctrl.HighlightedIndex = SelectedIndex;
		}
		
		internal void Draw (Rectangle clip, Graphics dc)
		{				
			Theme theme = ThemeEngine.Current;

			if (DropDownStyle == ComboBoxStyle.Simple)
				dc.FillRectangle (theme.ResPool.GetSolidBrush (Parent.BackColor), ClientRectangle);

			if (clip.IntersectsWith (text_area))
				ControlPaint.DrawBorder3D (dc, text_area, Border3DStyle.Sunken);

			int border = theme.Border3DSize.Width;

			// No edit control, we paint the edit ourselves
			if (dropdown_style == ComboBoxStyle.DropDownList) {
				DrawItemState state = DrawItemState.None;
				Rectangle item_rect = text_area;
				item_rect.X += border;
				item_rect.Y += border;
				item_rect.Width -= (button_area.Width + 2 * border);				
				item_rect.Height -= 2 * border;				
								
				if (Focused) {
					state = DrawItemState.Selected;
					state |= DrawItemState.Focus;
				}
				
				state |= DrawItemState.ComboBoxEdit;				
				OnDrawItem (new DrawItemEventArgs (dc, Font, item_rect, SelectedIndex, state, ForeColor, BackColor));
			}						
			
			if (show_dropdown_button) {
				dc.FillRectangle (theme.ResPool.GetSolidBrush (theme.ColorControl), button_area);

				if (!is_enabled)
					button_state = ButtonState.Inactive;
				
				theme.CPDrawComboButton (dc, button_area, button_state);
			}			
		}

		internal void DropDownListBox ()
		{
			if (DropDownStyle == ComboBoxStyle.Simple)
				return;			
			
			if (listbox_ctrl == null)
    				CreateComboListBox ();

			listbox_ctrl.Location = PointToScreen (new Point (text_area.X, text_area.Y + text_area.Height));
						
    			if (listbox_ctrl.ShowWindow ())    				
    				dropped_down = true;        				
    			
    			button_state = ButtonState.Pushed;				
    			if (dropdown_style == ComboBoxStyle.DropDownList)
    				Invalidate (text_area);
		}
		
		internal void DropDownListBoxFinished ()
		{
			if (DropDownStyle == ComboBoxStyle.Simple)
				return;			
				
			button_state = ButtonState.Normal;
			Invalidate (button_area);
			dropped_down = false;
		}
		
		private int FindStringCaseInsensitive (string search)
		{			
			if (search.Length == 0) {
				return -1;
			}
			
			for (int i = 0; i < Items.Count; i++) 
			{				
				if (String.Compare (GetItemText (Items[i]), 0, search, 0, search.Length, true) == 0)
					return i;
			}

			return -1;
		}

		internal int FindStringCaseInsensitive (string search, int start_index)
		{
			if (search.Length == 0) {
				return -1;
			}

			for (int i = 0; i < Items.Count; i++) {
				int index = (i + start_index) % Items.Count;
				if (String.Compare (GetItemText (Items [index]), 0, search, 0, search.Length, true) == 0)
					return index;
			}

			return -1;
		}

		private void OnKeyDownCB(object sender, KeyEventArgs e)
		{
			if (Items.Count == 0)
				return;

			switch (e.KeyCode) 
			{			
				case Keys.Up:
					SelectedIndex = Math.Max(SelectedIndex-1, 0);
					break;				
	
				case Keys.Down:
					SelectedIndex = Math.Min(SelectedIndex+1, Items.Count-1);
					break;
				
				case Keys.PageUp:
					if (listbox_ctrl != null)
						SelectedIndex = Math.Max(SelectedIndex- (listbox_ctrl.page_size-1), 0);
					break;				
	
				case Keys.PageDown:		
					if (listbox_ctrl != null)		
						SelectedIndex = Math.Min(SelectedIndex+(listbox_ctrl.page_size-1), Items.Count-1);
					break;
				
				default:
					break;
			}
		}
		
		void OnMouseDownCB (object sender, MouseEventArgs e)
    		{
			Rectangle area;
			if (DropDownStyle == ComboBoxStyle.DropDownList)
				area = ClientRectangle;
			else
				area = button_area;

			if (area.Contains (e.X, e.Y)) {
	    			DropDownListBox ();	    				
	    			Invalidate (button_area);
				Update ();
    			}
			Capture = true;
    		}

    		void OnMouseMoveCB (object sender, MouseEventArgs e)
    		{    			
			if (DropDownStyle == ComboBoxStyle.Simple)
				return;

			if (listbox_ctrl != null && listbox_ctrl.Visible) {
				Point location = listbox_ctrl.PointToClient (Control.MousePosition);
				if (listbox_ctrl.ClientRectangle.Contains (location))
					listbox_ctrl.Capture = true;
			}
    		}

    		void OnMouseUpCB (object sender, MouseEventArgs e)
    		{
			Capture = false;
			OnClick (EventArgs.Empty);

			if (dropped_down)
				listbox_ctrl.Capture = true;
    		}

		private void OnMouseWheelCB (object sender, MouseEventArgs me)
		{
			if (Items.Count == 0)
				return;

			if (listbox_ctrl != null && listbox_ctrl.Visible) {
				int lines = me.Delta / 120 * SystemInformation.MouseWheelScrollLines;
				listbox_ctrl.Scroll (-lines);
			} else {
				int lines = me.Delta / 120;
				int index = SelectedIndex - lines;
				if (index < 0)
					index = 0;
				else if (index >= Items.Count)
					index = Items.Count - 1;
				SelectedIndex = index;
			}
		}

		internal override void OnPaintInternal (PaintEventArgs pevent)
		{
			if (suspend_ctrlupdate)
    				return;
    				
			Draw (ClientRectangle, pevent.Graphics);			
		}
		
		private void OnTextBoxClick (object sender, EventArgs e)
		{
			OnClick (e);
		}

		private void OnTextChangedEdit (object sender, EventArgs e)
		{
			if (process_textchanged_event == false)
				return; 
				
			OnTextChanged (EventArgs.Empty);

			int item = FindStringCaseInsensitive (textbox_ctrl.Text);
			
			if (item == -1)
				return;

			// TODO:  THIS IS BROKEN-ISH
			// I don't think we should hilight, and setting the top item does weirdness
			// when there is no scrollbar
			
			if (listbox_ctrl != null) {
				listbox_ctrl.SetTopItem (item);
				listbox_ctrl.HighlightedIndex = item;
			}

			base.Text = textbox_ctrl.Text;
		}
		
		internal void SetControlText (string s)
		{		
			process_textchanged_event = false;
    			textbox_ctrl.Text = s;
    			process_textchanged_event = true;
    		}
		
		void UpdateComboBoxBounds ()
		{
			if (requested_height == -1)
				return;

			// Save the requested height since set bounds can destroy it
			int save_height = requested_height;
			SetBounds (0, 0, 0, requested_height, BoundsSpecified.Height);
			requested_height = save_height;
		}

		private void UpdatedItems ()
		{
			if (listbox_ctrl != null) {
				listbox_ctrl.UpdateLastVisibleItem ();
				listbox_ctrl.CalcListBoxArea ();
				listbox_ctrl.Refresh ();
			}
		}

		#endregion Private Methods

		[ListBindableAttribute (false)]
		public class ObjectCollection : IList, ICollection, IEnumerable
		{

			private ComboBox owner;
			internal ArrayList object_items = new ArrayList ();

			public ObjectCollection (ComboBox owner)
			{
				this.owner = owner;
			}

			#region Public Properties
			public int Count {
				get { return object_items.Count; }
			}

			public bool IsReadOnly {
				get { return false; }
			}

			[Browsable (false)]
			[DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
			public virtual object this [int index] {
				get {
					if (index < 0 || index >= Count)
						throw new ArgumentOutOfRangeException ("Index of out range");

					return object_items[index];
				}
				set {
					if (index < 0 || index >= Count)
						throw new ArgumentOutOfRangeException ("Index of out range");
					if (value == null)
						throw new ArgumentNullException ("value");

					object_items[index] = value;
					if (owner.listbox_ctrl != null)
						owner.listbox_ctrl.InvalidateItem (index);
					if (index == owner.SelectedIndex) {
						if (owner.textbox_ctrl == null)
							owner.Refresh ();
						else
							owner.textbox_ctrl.SelectedText = value.ToString ();
					}
				}
			}

			bool ICollection.IsSynchronized {
				get { return false; }
			}

			object ICollection.SyncRoot {
				get { return this; }
			}

			bool IList.IsFixedSize {
				get { return false; }
			}

			#endregion Public Properties
			
			#region Public Methods
			public int Add (object item)
			{
				int idx;

				idx = AddItem (item);
				owner.UpdatedItems ();
				return idx;
			}

			public void AddRange (object[] items)
			{
				if (items == null)
					throw new ArgumentNullException ("items");

				foreach (object mi in items)
					AddItem (mi);
					
				owner.UpdatedItems ();
			}

			public void Clear ()
			{
				owner.selected_index = -1;
				object_items.Clear ();
				owner.UpdatedItems ();
				owner.Refresh ();
			}
			
			public bool Contains (object obj)
			{
				if (obj == null)
					throw new ArgumentNullException ("obj");

				return object_items.Contains (obj);
			}

			public void CopyTo (object[] dest, int arrayIndex)
			{
				object_items.CopyTo (dest, arrayIndex);
			}

			void ICollection.CopyTo (Array dest, int index)
			{
				object_items.CopyTo (dest, index);
			}

			public IEnumerator GetEnumerator ()
			{
				return object_items.GetEnumerator ();
			}

			int IList.Add (object item)
			{
				return Add (item);
			}

			public int IndexOf (object value)
			{
				if (value == null)
					throw new ArgumentNullException ("value");

				return object_items.IndexOf (value);
			}

			public void Insert (int index,  object item)
			{
				if (index < 0 || index > Count)
					throw new ArgumentOutOfRangeException ("Index of out range");					
				if (item == null)
					throw new ArgumentNullException ("item");
				
				owner.BeginUpdate ();
				
				if (owner.Sorted)
					AddItem (item);
				else
					object_items.Insert (index, item);
												
				owner.EndUpdate ();	// Calls UpdatedItems
			}

			public void Remove (object value)
			{				
				if (value == null)
					return;

				if (IndexOf (value) == owner.SelectedIndex)
					owner.SelectedIndex = -1;
				
				RemoveAt (IndexOf (value));				
			}

			public void RemoveAt (int index)
			{
				if (index < 0 || index >= Count)
					throw new ArgumentOutOfRangeException ("Index of out range");
					
				if (index == owner.SelectedIndex)
					owner.SelectedIndex = -1;

				object_items.RemoveAt (index);
				owner.UpdatedItems ();
			}
			#endregion Public Methods

			#region Private Methods
			private int AddItem (object item)
			{
				if (item == null)
					throw new ArgumentNullException ("item");

				if (owner.Sorted) {
					int index = 0;
					foreach (object o in object_items) {
						if (String.Compare (item.ToString (), o.ToString ()) < 0) {
							object_items.Insert (index, item);
							return index;
						}
						index++;
					}
				}
				object_items.Add (item);
				return object_items.Count - 1;
			}
			
			internal void AddRange (IList items)
			{
				foreach (object mi in items)
					AddItem (mi);
										
				owner.UpdatedItems ();
			}

			internal void Sort ()
			{
				object_items.Sort ();
			}

			#endregion Private Methods
		}

		internal class ComboTextBox : TextBox {

			private ComboBox owner;

			public ComboTextBox (ComboBox owner)
			{
				this.owner = owner;
				ShowSelection = false;
			}

			internal void SetSelectable (bool selectable)
			{
				SetStyle (ControlStyles.Selectable, selectable);
			}

			internal void ActivateCaret (bool active)
			{
				if (active)
					document.CaretHasFocus ();
				else
					document.CaretLostFocus ();
			}
			
			protected override void OnGotFocus (EventArgs e)
			{
				owner.Select (false, true);
			}

			protected override void OnLostFocus (EventArgs e)
			{
				owner.Select (false, true);
			}			
		}

		internal class ComboListBox : Control
		{
			private ComboBox owner;			
			private VScrollBarLB vscrollbar_ctrl;
			private int top_item;			/* First item that we show the in the current page */
			private int last_item;			/* Last visible item */
			internal int page_size;			/* Number of listbox items per page */
			private Rectangle textarea_drawable;	/* Rectangle of the drawable text area */
			
			internal enum ItemNavigation
			{
				First,
				Last,
				Next,
				Previous,
				NextPage,
				PreviousPage,
			}
			
			class VScrollBarLB : VScrollBar
			{
				public VScrollBarLB ()
				{					
				}
				
				internal override bool InternalCapture {
					get { return Capture; }
					set { }
				}

				public void FireMouseDown (MouseEventArgs e) 
				{
					if (!Visible) 
						return;

					e = TranslateEvent (e);
					OnMouseDown (e);
				}	
				
				public void FireMouseUp (MouseEventArgs e) 
				{
					if (!Visible)
						return;

					e = TranslateEvent (e);
					OnMouseUp (e);
				}
				
				public void FireMouseMove (MouseEventArgs e) 
				{
					if (!Visible)
						return;

					e = TranslateEvent (e);
					OnMouseMove (e);
				}			
				
				MouseEventArgs TranslateEvent (MouseEventArgs e)
				{
					Point loc = PointToClient (Control.MousePosition);
		    			return new MouseEventArgs (e.Button, e.Clicks, loc.X, loc.Y, e.Delta);
				}
			}

			public ComboListBox (ComboBox owner)
			{					
				this.owner = owner;								
				top_item = 0;
				last_item = 0;
				page_size = 0;

				MouseWheel += new MouseEventHandler (OnMouseWheelCLB);

				SetStyle (ControlStyles.UserPaint | ControlStyles.AllPaintingInWmPaint, true);
				SetStyle (ControlStyles.ResizeRedraw | ControlStyles.Opaque, true);

				this.is_visible = false;
				Hwnd.ObjectFromHandle (this.Handle).no_activate = true;

				if (owner.DropDownStyle == ComboBoxStyle.Simple)
					InternalBorderStyle = BorderStyle.Fixed3D;
				else
					InternalBorderStyle = BorderStyle.FixedSingle;
			}

			protected override CreateParams CreateParams
			{
				get {
					CreateParams cp = base.CreateParams;					
					if (owner == null || owner.DropDownStyle == ComboBoxStyle.Simple)
						return cp;

					cp.Style ^= (int) WindowStyles.WS_CHILD;
					cp.Style |= (int) WindowStyles.WS_POPUP;
					cp.ExStyle |= (int) WindowExStyles.WS_EX_TOOLWINDOW | (int) WindowExStyles.WS_EX_TOPMOST;
					return cp;
				}
			}

			protected override void Select (bool directed, bool forward)
			{
				// Do nothing, we never want to be selected
			}

			internal override bool InternalCapture {
				get {
					return Capture;
				}

				set {
				}
			}

			int BorderWidth {
				get {
					switch (border_style) {
					case BorderStyle.Fixed3D:
						return ThemeEngine.Current.Border3DSize.Width;
					default:
						return ThemeEngine.Current.BorderSize.Width;
					}
				}
			}

			#region Private Methods			
			// Calcs the listbox area
			internal void CalcListBoxArea ()
			{				
				int width, height;
				bool show_scrollbar = false;
				
				if (owner.DropDownStyle == ComboBoxStyle.Simple) {
					Rectangle area = owner.listbox_area;
					width = area.Width;
					height = area.Height;
				}
				else { // DropDown or DropDownList
					
					width = owner.DropDownWidth;
					int count = (owner.Items.Count <= owner.MaxDropDownItems) ? owner.Items.Count : owner.MaxDropDownItems;				
					
					if (owner.DrawMode == DrawMode.OwnerDrawVariable) {						
						height = 0;
						for (int i = 0; i < count; i++) {
							height += owner.GetItemHeight (i);
						}
						
					} else	{
						height = owner.ItemHeight * count;
					}
				}
				
				page_size = height / owner.ItemHeight;

				if (owner.Items.Count <= owner.MaxDropDownItems) {					
					if (vscrollbar_ctrl != null)
						vscrollbar_ctrl.Visible = false;
				} else {					
					/* Need vertical scrollbar */
					if (vscrollbar_ctrl == null) {
						vscrollbar_ctrl = new VScrollBarLB ();
						vscrollbar_ctrl.Minimum = 0;
						vscrollbar_ctrl.SmallChange = 1;
						vscrollbar_ctrl.LargeChange = 1;
						vscrollbar_ctrl.Maximum = 0;
						vscrollbar_ctrl.ValueChanged += new EventHandler (VerticalScrollEvent);
						Controls.AddImplicit (vscrollbar_ctrl);
					}
					
					vscrollbar_ctrl.Height = height - 2 * BorderWidth;
							
					vscrollbar_ctrl.Location = new Point (width - vscrollbar_ctrl.Width - BorderWidth - 1, 0);

					vscrollbar_ctrl.Maximum = owner.Items.Count - 2;
					int large = (owner.DropDownStyle == ComboBoxStyle.Simple ? page_size : owner.maxdrop_items) - 1;
					if (large < 0)
						large = 0;
					vscrollbar_ctrl.LargeChange = large;
					show_scrollbar = vscrollbar_ctrl.Visible = true;

					int hli = HighlightedIndex;
					if (hli > 0) {
						hli = Math.Min (hli, vscrollbar_ctrl.Maximum);
						vscrollbar_ctrl.Value = hli;
					}
				}
				
				Size = new Size (width, height);
				textarea_drawable = ClientRectangle;
				textarea_drawable.Width = width;
				textarea_drawable.Height = height;				
				
				if (vscrollbar_ctrl != null && show_scrollbar)
					textarea_drawable.Width -= vscrollbar_ctrl.Width;

				last_item = LastVisibleItem ();
			}			

			private void Draw (Rectangle clip, Graphics dc)
			{	
				dc.FillRectangle (ThemeEngine.Current.ResPool.GetSolidBrush (owner.BackColor), clip);

				if (owner.Items.Count > 0) {
					
					for (int i = top_item; i <= last_item; i++) {
						Rectangle item_rect = GetItemDisplayRectangle (i, top_item);

						if (!clip.IntersectsWith (item_rect))
							continue;

						DrawItemState state = DrawItemState.None;

						if (i == HighlightedIndex) {
							state |= DrawItemState.Selected;
							
							if (owner.DropDownStyle == ComboBoxStyle.DropDownList) {
								state |= DrawItemState.Focus;
							}							
						}
							
						owner.OnDrawItem (new DrawItemEventArgs (dc, owner.Font, item_rect,
							i, state, owner.ForeColor, owner.BackColor));
					}
				}
			}

			int highlighted_index = -1;

			public int HighlightedIndex {
				get { return highlighted_index; }
				set { 
					if (highlighted_index == value)
						return;

					if (highlighted_index != -1 && highlighted_index < this.owner.Items.Count)
						Invalidate (GetItemDisplayRectangle (highlighted_index, top_item));
					highlighted_index = value;
    					if (highlighted_index != -1)
						Invalidate (GetItemDisplayRectangle (highlighted_index, top_item));
				}
			}

			private Rectangle GetItemDisplayRectangle (int index, int top_index)
			{
				if (index < 0 || index >= owner.Items.Count)
					throw new  ArgumentOutOfRangeException ("GetItemRectangle index out of range.");

				Rectangle item_rect = new Rectangle ();
				int height = owner.GetItemHeight (index);

				item_rect.X = 0;
				item_rect.Width = textarea_drawable.Width;
				if (owner.DrawMode == DrawMode.OwnerDrawVariable) {
					item_rect.Y = 0;
					for (int i = top_index; i < index; i++)
						item_rect.Y += owner.GetItemHeight (i);
				} else
					item_rect.Y = height * (index - top_index);

				item_rect.Height = height;
				return item_rect;
			}

			public void HideWindow ()
			{
				if (owner.DropDownStyle == ComboBoxStyle.Simple)
					return;
					
				Capture = false;
				Hide ();
				owner.DropDownListBoxFinished ();
			}

			private int IndexFromPointDisplayRectangle (int x, int y)
			{
	    			for (int i = top_item; i <= last_item; i++) {
					if (GetItemDisplayRectangle (i, top_item).Contains (x, y) == true)
						return i;
				}

				return -1;
			}

			public void InvalidateItem (int index)
			{
				if (Visible)
					Invalidate (GetItemDisplayRectangle (index, top_item));
			}

			private int LastVisibleItem ()
			{
				Rectangle item_rect;
				int top_y = textarea_drawable.Y + textarea_drawable.Height;
				int i = 0;				
				
				for (i = top_item; i < owner.Items.Count; i++) {
					item_rect = GetItemDisplayRectangle (i, top_item);				
					if (item_rect.Y + item_rect.Height > top_y) {
						return i;
					}
				}
				return i - 1;
			}

			public void SetTopItem (int item)
			{
				if (top_item == item)
					return;
				top_item = item;
				UpdateLastVisibleItem ();
				Invalidate ();
			}			

			bool scrollbar_grabbed = false;

			bool InScrollBar {
				get {
					if (vscrollbar_ctrl == null || !vscrollbar_ctrl.is_visible)
						return false;

					return vscrollbar_ctrl.Bounds.Contains (PointToClient (Control.MousePosition));
				}
			}

			protected override void OnMouseDown (MouseEventArgs e)
			{
				if (InScrollBar) {
					vscrollbar_ctrl.FireMouseDown (e);
					scrollbar_grabbed = true;
				}
			}

			protected override void OnMouseMove (MouseEventArgs e)
			{						
				if (owner.DropDownStyle == ComboBoxStyle.Simple)
					return;

				if (scrollbar_grabbed || (!Capture && InScrollBar)) {
					vscrollbar_ctrl.FireMouseMove (e);
					return;
				}

				Point pt = PointToClient (Control.MousePosition);
				int index = IndexFromPointDisplayRectangle (pt.X, pt.Y);

    				if (index != -1)
					HighlightedIndex = index;
			}
			
			protected override void OnMouseUp (MouseEventArgs e)
			{
	    			int index = IndexFromPointDisplayRectangle (e.X, e.Y);

				if (scrollbar_grabbed) {
					vscrollbar_ctrl.FireMouseUp (e);
					scrollbar_grabbed = false;
					if (index != -1)
						HighlightedIndex = index;
					return;
				}

    				if (index == -1) {    					
		    			HideWindow ();
					return;
				}

				owner.SelectedIndex = index;
				owner.OnSelectionChangeCommitted (new EventArgs ());
				HideWindow ();
			}

			internal override void OnPaintInternal (PaintEventArgs pevent)
			{				
				Draw (pevent.ClipRectangle,pevent.Graphics);
			}

			public bool ShowWindow ()
			{
				if (owner.DropDownStyle == ComboBoxStyle.Simple && owner.Items.Count == 0)
					return false;

				HighlightedIndex = owner.SelectedIndex;

				CalcListBoxArea ();				
				Show ();

				Refresh ();
				owner.OnDropDown (EventArgs.Empty);
				return true;
			}
			
			public void UpdateLastVisibleItem ()
			{
				last_item = LastVisibleItem ();
			}

			public void Scroll (int delta)
			{
				if (delta == 0 || vscrollbar_ctrl == null || !vscrollbar_ctrl.Visible)
					return;

				int max = owner.Items.Count - page_size;

				int val = vscrollbar_ctrl.Value + delta;
				if (val > max)
					val = max;
				else if (val < vscrollbar_ctrl.Minimum)
					val = vscrollbar_ctrl.Minimum;
				vscrollbar_ctrl.Value = val;
			}

			private void OnMouseWheelCLB (object sender, MouseEventArgs me)
			{
				if (owner.Items.Count == 0)
					return;

				int lines = me.Delta / 120 * SystemInformation.MouseWheelScrollLines;
				Scroll (-lines);
			}

			// Value Changed
			private void VerticalScrollEvent (object sender, EventArgs e)
			{				
				if (top_item == vscrollbar_ctrl.Value)
					return;

				top_item =  vscrollbar_ctrl.Value;
				UpdateLastVisibleItem ();
				Invalidate ();
			}			
			
			protected override void WndProc(ref Message m) {
				if (m.Msg == (int)Msg.WM_SETFOCUS) {
					if (m.WParam != IntPtr.Zero) {
						XplatUI.SetFocus(m.WParam);
					}
				}
				base.WndProc (ref m);
			}

			#endregion Private Methods
		}
	}
}