2007-03-19 Chris Toshok <toshok@ximian.com>

[mono-project.git] / mcs / class / Managed.Windows.Forms / System.Windows.Forms / DateTimePicker.cs

// 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) 2004-2005 Novell, Inc.
//
// Authors:
//      John BouAntoun  jba-mono@optusnet.com.au
//      Rolf Bjarne Kvinge      rolfkvinge@ya.com
//
// TODO:
//              - wire in all events from monthcalendar


using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Runtime.InteropServices;
using System.Windows.Forms;

namespace System.Windows.Forms {
#if NET_2_0
        [ClassInterface (ClassInterfaceType.AutoDispatch)]
        [DefaultBindingProperty ("Value")]
        [ComVisible (true)]
#endif
        [DefaultEvent("ValueChanged")]
        [DefaultProperty("Value")]
        [Designer("System.Windows.Forms.Design.DateTimePickerDesigner, " + Consts.AssemblySystem_Design, "System.ComponentModel.Design.IDesigner")]
        public class DateTimePicker : Control {

                #region Public variables
                
                // this class has to have the specified hour, minute and second, as it says in msdn
#if NET_2_0
                [EditorBrowsable (EditorBrowsableState.Never)]
                [Browsable (false)]
#endif
                public static readonly DateTime MaxDateTime = new DateTime (9998, 12, 31, 0, 0, 0);
#if NET_2_0
                [EditorBrowsable (EditorBrowsableState.Never)]
                [Browsable (false)]
#endif
                public static readonly DateTime MinDateTime = new DateTime (1753, 1, 1);

                internal const int check_box_size = 13;
                internal const int check_box_space = 4;
                
                #endregion      // Public variables
                
                #region Local variables
                
                protected static readonly Color DefaultMonthBackColor = ThemeEngine.Current.ColorWindow;
                protected static readonly Color DefaultTitleBackColor = ThemeEngine.Current.ColorActiveCaption;
                protected static readonly Color DefaultTitleForeColor = ThemeEngine.Current.ColorActiveCaptionText;
                protected static readonly Color DefaultTrailingForeColor = SystemColors.GrayText;
                
                internal MonthCalendar                  month_calendar;
                bool                                                    is_checked;
                string                                                  custom_format;
                LeftRightAlignment                              drop_down_align;
                DateTimePickerFormat                    format;
                DateTime                                                max_date;
                DateTime                                                min_date;
                bool                                                    show_check_box;
                bool                                                    show_up_down;
                DateTime                                                date_value;
#if NET_2_0
                bool                                                    right_to_left_layout;
#endif
                // variables used for drawing and such
                internal const int                                      up_down_width = check_box_size;
                internal bool                                   is_drop_down_visible;
                internal bool                                           is_up_pressed;
                internal bool                                           is_down_pressed;
                internal Timer                                          updown_timer;
                internal const int                                      initial_timer_delay = 500;
                internal const int                                      subsequent_timer_delay = 100;
                internal bool                                           is_checkbox_selected;

                // variables for determining how to format the string
                internal PartData[]                                     part_data;

                #endregion      // Local variables
                
                #region DateTimePickerAccessibleObject Subclass
                [ComVisible(true)]
                public class DateTimePickerAccessibleObject : ControlAccessibleObject {
                        #region DateTimePickerAccessibleObject Local Variables
                        private new DateTimePicker      owner;
                        #endregion      // DateTimePickerAccessibleObject Local Variables

                        #region DateTimePickerAccessibleObject Constructors
                        public DateTimePickerAccessibleObject(DateTimePicker owner) : base(owner) {
                                this.owner = owner;
                        }
                        #endregion      // DateTimePickerAccessibleObject Constructors

                        #region DateTimePickerAccessibleObject Properties
#if NET_2_0
                        public override string KeyboardShortcut {
                                get {
                                        return base.KeyboardShortcut;
                                }
                        }

                        public override AccessibleRole Role {
                                get {
                                        return base.Role;
                                }
                        }
#endif
                        public override AccessibleStates State {
                                get {
                                        AccessibleStates        retval;

                                        retval = AccessibleStates.Default;

                                        if (owner.Checked) {
                                                retval |= AccessibleStates.Checked;
                                        }

                                        return retval;
                                }
                        }

                        public override string Value {
                                get {
                                        return owner.Text;
                                }
                        }
                        #endregion      // DateTimePickerAccessibleObject Properties
                }
                #endregion      // DateTimePickerAccessibleObject Sub-class

                #region public constructors
                
                // only public constructor
                public DateTimePicker () {
                
                        // initialise the month calendar
                        month_calendar = new MonthCalendar (this);
                        month_calendar.CalendarDimensions = new Size (1, 1);
                        month_calendar.MaxSelectionCount = 1;
                        month_calendar.ForeColor = Control.DefaultForeColor;
                        month_calendar.BackColor = DefaultMonthBackColor;
                        month_calendar.TitleBackColor = DefaultTitleBackColor;
                        month_calendar.TitleForeColor = DefaultTitleForeColor;
                        month_calendar.TrailingForeColor = DefaultTrailingForeColor;
                        month_calendar.Visible = false;
                        // initialize the timer
                        updown_timer = new Timer();
                        updown_timer.Interval = initial_timer_delay;

                        
                        // initialise other variables
                        is_checked = true;
                        custom_format = null;
                        drop_down_align = LeftRightAlignment.Left;
                        format = DateTimePickerFormat.Long;
                        max_date = MaxDateTime;
                        min_date = MinDateTime;
                        show_check_box = false;
                        show_up_down = false;
                        date_value = DateTime.Now;
                                                
                        is_drop_down_visible = false;
                        BackColor = SystemColors.Window;
                        ForeColor = SystemColors.WindowText;
                        
                        month_calendar.DateChanged += new DateRangeEventHandler (MonthCalendarDateChangedHandler);
                        month_calendar.DateSelected += new DateRangeEventHandler (MonthCalendarDateSelectedHandler);
                        month_calendar.LostFocus += new EventHandler (MonthCalendarLostFocusHandler);
                        updown_timer.Tick += new EventHandler (UpDownTimerTick);
                        KeyPress += new KeyPressEventHandler (KeyPressHandler);
                        KeyDown += new KeyEventHandler (KeyDownHandler);
                        LostFocus += new EventHandler (LostFocusHandler);
                        MouseDown += new MouseEventHandler (MouseDownHandler);                  
                        MouseUp += new MouseEventHandler (MouseUpHandler);
                        Paint += new PaintEventHandler (PaintHandler);
                        Resize += new EventHandler (ResizeHandler);
                        SetStyle (ControlStyles.UserPaint | ControlStyles.StandardClick, false);
                        SetStyle (ControlStyles.FixedHeight, true);
                        SetStyle (ControlStyles.Selectable, true);

                        CalculateFormats ();
                }
                
                #endregion
                
                #region public properties
                
                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public override Color BackColor {
                        set {
                                base.BackColor = value;
                        }
                        get {
                                return base.BackColor;
                        }
                }
                
                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public override Image BackgroundImage {
                        set {
                                base.BackgroundImage = value;
                        }
                        get {
                                return base.BackgroundImage;
                        }
                }

#if NET_2_0
                [Browsable (false)]
                [EditorBrowsable (EditorBrowsableState.Never)]
                public override ImageLayout BackgroundImageLayout {
                        get{
                                return base.BackgroundImageLayout;
                        }
                        set {
                                base.BackgroundImageLayout = value;
                        }
                }
#endif

                [AmbientValue(null)]
                [Localizable(true)]
                public Font CalendarFont {
                        set {
                                month_calendar.Font = value;
                        }
                        get {
                                return month_calendar.Font;
                        }
                }

                public Color CalendarForeColor {
                        set {
                                month_calendar.ForeColor = value;
                        }
                        get {
                                return month_calendar.ForeColor;
                        }
                }

                public Color CalendarMonthBackground {
                        set {
                                month_calendar.BackColor = value;
                        }
                        get {
                                return month_calendar.BackColor;
                        }
                }

                public Color CalendarTitleBackColor {
                        set {
                                month_calendar.TitleBackColor = value;
                        }
                        get {
                                return month_calendar.TitleBackColor;
                        }
                }

                public Color CalendarTitleForeColor {
                        set {
                                month_calendar.TitleForeColor = value;
                        }
                        get {
                                return month_calendar.TitleForeColor;
                        }
                }

                public Color CalendarTrailingForeColor {
                        set {
                                month_calendar.TrailingForeColor = value;
                        }
                        get {
                                return month_calendar.TrailingForeColor;
                        }
                }
                
                // when checked the value is grayed out
                [Bindable(true)]
                [DefaultValue(true)]
                public bool Checked {
                        set {
                                if (is_checked != value) {
                                        is_checked = value;
                                        // invalidate the value inside this control
                                        if (ShowCheckBox) {
                                                for (int i = 0; i < part_data.Length; i++)
                                                        part_data [i].is_selected = false;
                                                Invalidate (date_area_rect);
                                        }
                                }
                        }
                        get {
                                return is_checked;
                        }
                }
                
                // the custom format string to format this control with
#if NET_2_0
                [Localizable (true)]
#endif
                [DefaultValue(null)]
                [RefreshProperties(RefreshProperties.Repaint)]
                public string CustomFormat {
                        set {
                                if (custom_format != value) {
                                        custom_format = value;
                                        if (this.Format == DateTimePickerFormat.Custom) {
                                                CalculateFormats ();
                                        }
                                }
                        }
                        get {
                                return custom_format;
                        }
                }
                
#if NET_2_0
                [EditorBrowsable (EditorBrowsableState.Never)]
                protected override bool DoubleBuffered {
                        get {
                                return base.DoubleBuffered;
                        }
                        set {
                                base.DoubleBuffered = value;
                        }
                }
#endif

                // which side the drop down is to be aligned on
                [DefaultValue(LeftRightAlignment.Left)]
                [Localizable(true)]
                public LeftRightAlignment DropDownAlign {
                        set {
                                if (drop_down_align != value) {
                                        drop_down_align = value;
                                }
                        }
                        get {
                                return drop_down_align;
                        }
                }

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public override Color ForeColor {
                        set {
                                base.ForeColor = value;
                        }
                        get {
                                return base.ForeColor;
                        }
                }
                
                // the format of the date time picker text, default is long
                [RefreshProperties(RefreshProperties.Repaint)]
                public DateTimePickerFormat Format {
                        set {
                                if (format != value) {
                                        format = value;
                                        RecreateHandle (); // MS recreates the handle on every format change.
                                        CalculateFormats ();
                                        this.OnFormatChanged (EventArgs.Empty);
                                        // invalidate the value inside this control
                                        this.Invalidate (date_area_rect);
                                }
                        }
                        get {
                                return format;
                        }
                }
                
                public DateTime MaxDate {
                        set {
                                if (value < min_date) {
                                        throw new ArgumentException ();
                                }
                                if (value > MaxDateTime) {
                                        throw new SystemException ();
                                }
                                if (max_date != value) {
                                        max_date = value;
                                        
                                        // TODO: verify this is correct behaviour when value > max date
                                        if (Value > max_date) {
                                                Value = max_date;
                                                // invalidate the value inside this control
                                                this.Invalidate (date_area_rect);
                                        }
                                }
                        }
                        get {
                                return max_date;
                        }
                }
                
#if NET_2_0
                public static DateTime MaximumDateTime {
                        get {
                                return MaxDateTime;
                        }
                }
#endif
                
                public DateTime MinDate {
                        set {
                                if (value < min_date) {
                                        throw new ArgumentException ();
                                }
                                if (value < MinDateTime) {
                                        throw new SystemException ();
                                }
                                if (min_date != value) {
                                        min_date = value;
                                        
                                        // TODO: verify this is correct behaviour when value > max date
                                        if (Value < min_date) {
                                                Value = min_date;
                                                // invalidate the value inside this control
                                                this.Invalidate (date_area_rect);
                                        }
                                }
                        }
                        get {
                                return min_date;
                        }
                }
#if NET_2_0
                public static DateTime MinimumDateTime {
                        get {
                                return MinDateTime;
                        }
                }
#endif
#if NET_2_0
                [EditorBrowsable (EditorBrowsableState.Never)]
                [DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
                [Browsable (false)]
                public new Padding Padding {
                        get { return base.Padding; }
                        set { base.Padding = value; }
                }
#endif

                // the prefered height to draw this control using current font
                [Browsable(false)]
                [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
                public int PreferredHeight {
                        get {
                                // Make it proportional
                                return (int) Math.Ceiling (Font.Height * 1.5);
                        }
                }

#if NET_2_0
                [DefaultValue (false)]
                [Localizable (true)]
                public virtual bool RightToLeftLayout {
                        get {
                                return right_to_left_layout;
                        }
                        set {
                                if (right_to_left_layout != value) {
                                        right_to_left_layout = value;
                                        OnRightToLeftLayoutChanged (EventArgs.Empty);
                                }
                        }
                }
#endif

                // whether or not the check box is shown
                [DefaultValue(false)]
                public bool ShowCheckBox {
                        set {
                                if (show_check_box != value) {
                                        show_check_box = value;
                                        // invalidate the value inside this control
                                        this.Invalidate (date_area_rect);
                                }
                        }
                        get {
                                return show_check_box;
                        }
                }
                
                // if true show the updown control, else popup the monthcalendar
                [DefaultValue(false)]
                public bool ShowUpDown {
                        set {
                                if (show_up_down != value) {
                                        show_up_down = value;
                                        // need to invalidate the whole control
                                        this.Invalidate ();
                                }
                        }
                        get {
                                return show_up_down;
                        }
                }

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Advanced)]
                [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
                public override string Text {
                        set {
                                DateTime parsed_value;
                                
                                if (value == null || value == string.Empty) {
                                        Value = DateTime.Now;
                                        OnTextChanged (EventArgs.Empty);
                                        return;
                                }
                                
                                if (format == DateTimePickerFormat.Custom) {
                                        // TODO: if the format is a custom format we need to do a custom parse here
                                        // This implementation will fail if the custom format is set to something that can
                                        // be a standard datetime format string
                                        // http://msdn2.microsoft.com/en-us/library/az4se3k1.aspx
                                        parsed_value = DateTime.ParseExact (value, GetExactFormat (), null);
                                } else {
                                        parsed_value = DateTime.ParseExact (value, GetExactFormat (), null);
                                }
                                
                                if (date_value != parsed_value) {
                                        Value = parsed_value;
                                }
                        }
                        get {
                                if (!IsHandleCreated)
                                        return "";
                                
                                if (format == DateTimePickerFormat.Custom) {
                                        System.Text.StringBuilder result = new System.Text.StringBuilder ();
                                        for (int i = 0; i < part_data.Length; i++) { 
                                                result.Append(part_data[i].GetText(date_value));
                                        }
                                        return result.ToString ();
                                } else {
                                        return Value.ToString (GetExactFormat ());
                                }
                        }
                }       

                [Bindable(true)]
                [RefreshProperties(RefreshProperties.All)]
                public DateTime Value {
                        set {
                                if (date_value != value) {
                                        date_value = value;
                                        this.OnValueChanged (EventArgs.Empty);
                                        this.Invalidate (date_area_rect);
                                }
                        }
                        get {
                                return date_value;
                        }                       
                }

                #endregion      // public properties
                
                #region public methods
                
                // just return the text value
                public override string ToString () {
                        return this.Text;
                } 
                                
                #endregion      // public methods
                
                #region public events
                static object CloseUpEvent = new object ();
                static object DropDownEvent = new object ();
                static object FormatChangedEvent = new object ();
                static object ValueChangedEvent = new object ();
#if NET_2_0
                static object RightToLeftLayoutChangedEvent = new object ();
#endif

                // raised when the monthcalendar is closed
                public event EventHandler CloseUp {
                        add { Events.AddHandler (CloseUpEvent, value); }
                        remove { Events.RemoveHandler (CloseUpEvent, value); }
                }
                
                // raised when the monthcalendar is opened
                public event EventHandler DropDown {
                        add { Events.AddHandler (DropDownEvent, value); }
                        remove { Events.RemoveHandler (DropDownEvent, value); }
                }
                
                // raised when the format of the value is changed
                public event EventHandler FormatChanged {
                        add { Events.AddHandler (FormatChangedEvent, value); }
                        remove { Events.RemoveHandler (FormatChangedEvent, value); }
                }
                
                // raised when the date Value is changed
                public event EventHandler ValueChanged {
                        add { Events.AddHandler (ValueChangedEvent, value); }
                        remove { Events.RemoveHandler (ValueChangedEvent, value); }
                }

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public new event EventHandler BackColorChanged {
                        add {
                                base.BackColorChanged += value;
                        }

                        remove {
                                base.BackColorChanged -= value;
                        }
                }

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

                        remove {
                                base.BackgroundImageChanged -= value;
                        }
                }
#if NET_2_0
                [Browsable (false)]
                [EditorBrowsable (EditorBrowsableState.Never)]
                public new event EventHandler BackgroundImageLayoutChanged {
                        add
                        {
                                base.BackgroundImageLayoutChanged += value;
                        }

                        remove
                        {
                                base.BackgroundImageLayoutChanged -= value;
                        }
                }
                
                [Browsable (false)]
                [EditorBrowsable (EditorBrowsableState.Never)]
                public new event EventHandler Click {
                        add {
                                base.Click += value;
                        }
                        remove {
                                base.Click -= value;
                        }
                }
                
                [Browsable (false)]
                [EditorBrowsable (EditorBrowsableState.Never)]
                public new event EventHandler DoubleClick {
                        add {
                                base.DoubleClick += value;
                        }
                        remove {
                                base.DoubleClick -= value;
                        }
                }
#endif

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public new event EventHandler ForeColorChanged {
                        add {
                                base.ForeColorChanged += value;
                        }

                        remove {
                                base.ForeColorChanged -= value;
                        }
                }
#if NET_2_0
                [Browsable (false)]
                [EditorBrowsable (EditorBrowsableState.Never)]
                public new event MouseEventHandler MouseClick {
                        add {
                                base.MouseClick += value;
                        }
                        remove {
                                base.MouseClick -= value;
                        }
                }
                
                [Browsable (false)]
                [EditorBrowsable (EditorBrowsableState.Never)]
                public new event MouseEventHandler MouseDoubleClick {
                        add {
                                base.MouseDoubleClick += value;
                        }
                        remove {
                                base.MouseDoubleClick -= value;
                        }
                }

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

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public new event PaintEventHandler Paint {
                        add {
                                base.Paint += value;
                        }

                        remove {
                                base.Paint -= value;
                        }
                }
#if NET_2_0
                public event EventHandler RightToLeftLayoutChanged {
                        add {
                                Events.AddHandler (RightToLeftLayoutChangedEvent, value);
                        }
                        remove {
                                Events.RemoveHandler (RightToLeftLayoutChangedEvent, value);
                        }
                }
#endif

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Advanced)]
                public new event EventHandler TextChanged {
                        add {
                                base.TextChanged += value;
                        }

                        remove {
                                base.TextChanged -= value;
                        }
                }
                #endregion      // public events
                
                #region protected properties

                // not sure why we're overriding this one               
                protected override CreateParams CreateParams {
                        get {
                                return base.CreateParams;
                        }
                }
                
                // specify the default size for this control
                protected override Size DefaultSize {
                        get {
                                // todo actually measure this properly
                                return new Size (200, PreferredHeight);
                        }
                }
                
                #endregion      // protected properties
                
                #region protected methods
                
                // not sure why we're overriding this one
                protected override AccessibleObject CreateAccessibilityInstance () {
                        return base.CreateAccessibilityInstance ();
                }
                
                // not sure why we're overriding this one
                protected override void CreateHandle () {
                        base.CreateHandle ();
                }
                
                // not sure why we're overriding this one
                protected override void DestroyHandle () {
                        base.DestroyHandle ();
                }

#if !NET_2_0
                // not sure why we're overriding this one
                protected override void Dispose (bool disposing) {
                        updown_timer.Dispose ();
                        base.Dispose (disposing);
                }
#endif

                // find out if this key is an input key for us, depends on which date part is focused
                protected override bool IsInputKey (Keys keyData) {
                        switch (keyData)
                        {
                                case Keys.Up:
                                case Keys.Down:
                                case Keys.Left:
                                case Keys.Right:
                                        return true;
                        }
                        return false;
                }
                
                // raises the CloseUp event
                protected virtual void OnCloseUp (EventArgs eventargs) {
                        EventHandler eh = (EventHandler)(Events [CloseUpEvent]);
                        if (eh != null)
                                eh (this, eventargs);
                }
                
                // raise the drop down event
                protected virtual void OnDropDown (EventArgs eventargs) {
                        EventHandler eh = (EventHandler)(Events [DropDownEvent]);
                        if (eh != null)
                                eh (this, eventargs);
                }

                protected override void OnFontChanged(EventArgs e) {
                        // FIXME - do we need to update/invalidate/recalc our stuff?
                        month_calendar.Font = Font;
                        Size = new Size (Size.Width, PreferredHeight);

                        base.OnFontChanged (e);
                }
                
                // raises the format changed event
                protected virtual void OnFormatChanged (EventArgs e) {
                        EventHandler eh = (EventHandler)(Events [FormatChangedEvent]);
                        if (eh != null)
                                eh (this, e);
                }
#if NET_2_0
                protected override void  OnHandleCreated (EventArgs e) {
                         base.OnHandleCreated(e);
                }
                protected override void  OnHandleDestroyed (EventArgs e) {
                         base.OnHandleDestroyed(e);
                }
                
                [EditorBrowsable (EditorBrowsableState.Advanced)]
                protected virtual void OnRightToLeftLayoutChanged (EventArgs e) {
                        EventHandler eh = (EventHandler) Events [RightToLeftLayoutChangedEvent];
                        if (eh != null)
                                eh (this, e);
                }
#endif
                // not sure why we're overriding this one 
                protected override void OnSystemColorsChanged (EventArgs e) {
                        base.OnSystemColorsChanged (e);
                }
                
                // raise the ValueChanged event
                protected virtual void OnValueChanged (EventArgs eventargs) {
                        EventHandler eh = (EventHandler)(Events [ValueChangedEvent]);
                        if (eh != null)
                                eh (this, eventargs);
                }
                
                // overridden to set the bounds of this control properly
                protected override void SetBoundsCore(int x, int y, int width, int height, BoundsSpecified specified) {
                        // TODO: ensure I implemented the bounds core setting properly.
                        if ((specified & BoundsSpecified.Height) == BoundsSpecified.Height ||
                                (specified & BoundsSpecified.Size) == BoundsSpecified.Size)  {
                                base.SetBoundsCore (x, y, width, DefaultSize.Height, specified);
                        } else {
                                base.SetBoundsCore (x, y, width, height, specified);
                        }
                        
                        // need to set the rectangles for all the support internal rects
                        // this is done here as a optimisation since this is an array of rects
                        if ((specified & BoundsSpecified.X) == BoundsSpecified.X ||
                                (specified & BoundsSpecified.Y) == BoundsSpecified.Y) {
                                // TODO set up all the datepart rects
                        }
                }

                // not sure why we're overriding this
                protected override void WndProc (ref Message m) {
                        base.WndProc (ref m);
                }
                
                #endregion      // protected methods
                
                #region internal / private properties
                
                // this is the region that the date and the check box is drawn on
                internal Rectangle date_area_rect {
                        get {
                                Rectangle rect = this.ClientRectangle;
                                if (ShowUpDown) {
                                        // set the space to the left of the up/down button
                                        if (rect.Width > (up_down_width + 4)) {
                                                rect.Width -= (up_down_width + 4);
                                        } else {
                                                rect.Width = 0;
                                        }
                                } else {
                                        // set the space to the left of the up/down button
                                        // TODO make this use up down button
                                        if (rect.Width > (SystemInformation.VerticalScrollBarWidth + 4)) {
                                                rect.Width -= SystemInformation.VerticalScrollBarWidth;
                                        } else {
                                                rect.Width = 0;
                                        }
                                }
                                
                                rect.Inflate (-2, -2);
                                return rect;
                        }
                }

                internal Rectangle CheckBoxRect {
                        get {
                                Rectangle retval = new Rectangle (check_box_space, ClientSize.Height / 2 - check_box_size / 2, 
                                                check_box_size, check_box_size);
                                return retval;
                        }
                }
                
                // the rectangle for the drop down arrow
                internal Rectangle drop_down_arrow_rect {
                        get {
                                Rectangle rect = this.ClientRectangle;
                                rect.X = rect.Right - SystemInformation.VerticalScrollBarWidth - 2;
                                if (rect.Width > (SystemInformation.VerticalScrollBarWidth + 2)) {
                                        rect.Width = SystemInformation.VerticalScrollBarWidth;
                                } else {
                                        rect.Width = Math.Max (rect.Width - 2, 0);
                                }
                                
                                rect.Inflate (0, -2);
                                return rect;
                        }
                }
                
                // the part of the date that is currently hilighted
                internal Rectangle hilight_date_area {
                        get {
                                // TODO: put hilighted part calculation in here
                                return Rectangle.Empty;
                        }
                }       
                        
                #endregion
                
                #region internal / private methods

                private void ResizeHandler (object sender, EventArgs e)
                {
                        Invalidate ();
                }

                private void UpDownTimerTick (object sender, EventArgs e)
                {
                        if (updown_timer.Interval == initial_timer_delay)
                                updown_timer.Interval = subsequent_timer_delay;

                        if (is_down_pressed)
                                IncrementSelectedPart (-1);
                        else if (is_up_pressed)
                                IncrementSelectedPart (1);
                        else
                                updown_timer.Enabled = false;
                }
                
                // calculates the maximum width 
                internal Single CalculateMaxWidth(string format, Graphics gr, StringFormat string_format)
                {
                        SizeF size;
                        float result = 0;
                        string text;
                        Font font = this.Font;

                        switch (format)
                        {
                                case "M":
                                case "MM":
                                case "MMM":
                                case "MMMM":
                                        for (int i = 1; i <= 12; i++) {
                                                text = PartData.GetText (Value.AddMonths (i), format);
                                                size = gr.MeasureString (text, font, int.MaxValue, string_format);
                                                result = Math.Max (result, size.Width);
                                        }
                                        return result;
                                case "d":
                                case "dd":
                                case "ddd":
                                case "dddd":
                                        for (int i = 1; i <= 12; i++) {
                                                text = PartData.GetText (Value.AddDays (i), format);
                                                size = gr.MeasureString (text, font, int.MaxValue, string_format);
                                                result = Math.Max (result, size.Width);
                                        }
                                        return result;
                                case "h":
                                case "hh":
                                        for (int i = 1; i <= 12; i++) {
                                                text = PartData.GetText (Value.AddHours (i), format);
                                                size = gr.MeasureString (text, font, int.MaxValue, string_format);
                                                result = Math.Max (result, size.Width);
                                        }
                                        return result;
                                case "H":
                                case "HH":
                                        for (int i = 1; i <= 24; i++) {
                                                text = PartData.GetText (Value.AddDays (i), format);
                                                size = gr.MeasureString (text, font, int.MaxValue, string_format);
                                                result = Math.Max (result, size.Width);
                                        }
                                        return result;
                                case "m":
                                case "mm":
                                        for (int i = 1; i <= 60; i++) {
                                                text = PartData.GetText (Value.AddMinutes (i), format);
                                                size = gr.MeasureString (text, font, int.MaxValue, string_format);
                                                result = Math.Max (result, size.Width);
                                        }
                                        return result;
                                case "s":
                                case "ss":
                                        for (int i = 1; i <= 60; i++) {
                                                text = PartData.GetText (Value.AddSeconds (i), format);
                                                size = gr.MeasureString (text, font, int.MaxValue, string_format);
                                                result = Math.Max (result, size.Width);
                                        }
                                        return result;
                                case "t":
                                case "tt":
                                        for (int i = 1; i <= 2; i++) {
                                                text = PartData.GetText (Value.AddHours (i * 12), format);
                                                size = gr.MeasureString (text, font, int.MaxValue, string_format);
                                                result = Math.Max (result, size.Width);
                                        }
                                        return result;
                                case "y":
                                case "yy":
                                case "yyyy":
                                        for (int i = 1; i <= 10; i++) {
                                                text = PartData.GetText (Value.AddYears (i), format);
                                                size = gr.MeasureString (text, font, int.MaxValue, string_format);
                                                result = Math.Max (result, size.Width);
                                        }
                                        return result;
                                default:
                                        return gr.MeasureString (format, font, int.MaxValue, string_format).Width;
                        }
                }

                // returns the format of the date as a string 
                // (i.e. resolves the Format enum values to it's corresponding string format)
                // Why CurrentCulture and not CurrentUICulture is explained here:
                // http://blogs.msdn.com/michkap/archive/2007/01/11/1449754.aspx
                private string GetExactFormat()
                {
                        switch (this.format) {
                        case DateTimePickerFormat.Long:
                                return Threading.Thread.CurrentThread.CurrentCulture.DateTimeFormat.LongDatePattern;
                        case DateTimePickerFormat.Short:
                                return Threading.Thread.CurrentThread.CurrentCulture.DateTimeFormat.ShortDatePattern;
                        case DateTimePickerFormat.Time:
                                return Threading.Thread.CurrentThread.CurrentCulture.DateTimeFormat.LongTimePattern;
                        case DateTimePickerFormat.Custom:
                                return this.custom_format == null ? String.Empty : this.custom_format;
                        default:
                                return Threading.Thread.CurrentThread.CurrentCulture.DateTimeFormat.LongDatePattern;
                        }
                }

                private void CalculateFormats()
                {
                        string real_format;
                        System.Text.StringBuilder literal = new System.Text.StringBuilder ();
                        System.Collections.ArrayList formats = new ArrayList ();
                        bool is_literal = false;
                        char lastch = (char) 0;
                        char ch;

                        real_format = GetExactFormat ();

                        // parse the format string
                        for (int i = 0; i < real_format.Length; i++)
                        {
                                ch = real_format [i];

                                if (is_literal && ch != '\'')
                                {
                                        literal.Append (ch);
                                        continue;
                                }

                                switch (ch)
                                {
                                        case 't':
                                        case 'd':
                                        case 'h':
                                        case 'H':
                                        case 'm':
                                        case 'M':
                                        case 's':
                                        case 'y':
                                        case 'g': // Spec says nothing about g, but it seems to be treated like spaces.
                                                if (!(lastch == ch || lastch == 0) && literal.Length != 0)
                                                {
                                                        formats.Add (new PartData(literal.ToString (), false));
                                                        literal.Length = 0;
                                                }
                                                literal.Append (ch);
                                                break;
                                        case '\'':
                                                if (is_literal && i < real_format.Length - 1 && real_format [i + 1] == '\'') {
                                                        literal.Append (ch);
                                                        i++;
                                                        break;
                                                }
                                                if (literal.Length == 0) {
                                                        is_literal = !is_literal;
                                                        break;
                                                }
                                                formats.Add (new PartData (literal.ToString (), is_literal));
                                                literal.Length = 0;
                                                is_literal = !is_literal;
                                                break;
                                        default:
                                                if (literal.Length != 0)
                                                {
                                                        formats.Add (new PartData(literal.ToString (), false));
                                                        literal.Length = 0;
                                                }
                                                formats.Add (new PartData (ch.ToString(), true));
                                                break;

                                }
                                lastch = ch;
                        }
                        if (literal.Length >= 0)
                                formats.Add (new PartData (literal.ToString (), is_literal));

                        part_data = new PartData [formats.Count];
                        formats.CopyTo (part_data);
                }

                private Point CalculateDropDownLocation (Rectangle parent_control_rect, Size child_size, bool align_left)
                {
                        // default bottom left
                        Point location = new Point(parent_control_rect.Left + 5, parent_control_rect.Bottom);
                        // now adjust the alignment
                        if (!align_left) {
                                location.X = parent_control_rect.Right - child_size.Width;                              
                        }
                        
                        Point screen_location = PointToScreen (location);                       
                        Rectangle working_area = Screen.FromControl(this).WorkingArea;
                        // now adjust if off the right side of the screen                       
                        if (screen_location.X < working_area.X) {
                                screen_location.X = working_area.X;
                        }  
                        // now adjust if it should be displayed above control
                        if (screen_location.Y + child_size.Height > working_area.Bottom) {
                                screen_location.Y -= (parent_control_rect.Height + child_size.Height);
                        }

                        // since the parent of the month calendar is the form, adjust accordingly.
                        screen_location = month_calendar.Parent.PointToClient(screen_location);

                        return screen_location;
                }
                
                // actually draw this control
                internal void Draw (Rectangle clip_rect, Graphics dc)
                {                       
                        ThemeEngine.Current.DrawDateTimePicker (dc, clip_rect, this);
                }                       
                
                // drop the calendar down
                internal void DropDownMonthCalendar ()
                {
                        // ensure the right date is set for the month_calendar
                        month_calendar.SetDate (this.date_value);
                        // get a rectangle that has the dimensions of the text area,
                        // but the height of the dtp control.
                        Rectangle align_area = this.date_area_rect;
                        align_area.Y = this.ClientRectangle.Y;
                        align_area.Height = this.ClientRectangle.Height;

                        month_calendar.Parent = this.FindForm ();
                        // establish the month calendar's location
                        month_calendar.Location = CalculateDropDownLocation (
                                align_area,
                                month_calendar.Size,
                                (this.DropDownAlign == LeftRightAlignment.Left));
                        month_calendar.Show ();
                        month_calendar.Focus ();
                        month_calendar.Capture = true;

                        // fire any registered events
                        // XXX should this just call OnDropDown?
                        EventHandler eh = (EventHandler)(Events [DropDownEvent]);
                        if (eh != null)
                                eh (this, EventArgs.Empty);
                }
                
                // hide the month calendar
                internal void HideMonthCalendar () 
                {
                        this.is_drop_down_visible = false;
                        Invalidate (drop_down_arrow_rect);
                        month_calendar.Capture = false;
                        if (month_calendar.Visible) {
                                month_calendar.Hide ();
                        }
        }

                private int GetSelectedPartIndex()
                {
                        for (int i = 0; i < part_data.Length; i++)
                        {
                                if (part_data[i].is_selected && !part_data[i].is_literal)
                                        return i;
                        }
                        return -1;
                }

                private void IncrementSelectedPart(int delta)
                {
                        int selected_index = GetSelectedPartIndex();

                        if (selected_index == -1) {
                                return;
                        }
                        
                        switch (part_data[selected_index].value)
                        {
                                case "d":
                                case "dd": // number day formats
                                        if (delta < 0) {
                                                if (Value.Day == 1)
                                                        SetPart(DateTime.DaysInMonth(Value.Year, Value.Month), 'd');
                                                else
                                                        SetPart(Value.Day + delta, 'd');
                                        } else {
                                                if (Value.Day == DateTime.DaysInMonth(Value.Year, Value.Month))
                                                        SetPart(1, 'd');
                                                else
                                                        SetPart(Value.Day + delta, 'd') ;
                                        }
                                        break;
                                case "ddd":
                                case "dddd": // text day formats
                                        Value = Value.AddDays(delta);
                                        break;
                                case "h":
                                case "hh":
                                case "H":
                                case "HH": // hour formats
                                        SetPart(Value.Hour + delta, 'h');
                                        break;
                                case "m":
                                case "mm": // minute formats
                                        SetPart(Value.Minute + delta, 'm');
                                        break;
                                case "M":
                                case "MM":
                                case "MMM":
                                case "MMMM": // month formats
                                        SetPart(Value.Month + delta, 'M');
                                        break;
                                case "s":
                                case "ss": // second format
                                        SetPart(Value.Second + delta, 's');
                                        break;
                                case "t":
                                case "tt": // AM / PM specifier
                                        SetPart(Value.Hour + delta * 12, 'h');
                                        break;
                                case "y":
                                case "yy":
                                case "yyy":
                                case "yyyy":
                                        SetPart(Value.Year + delta, 'y');
                                        break;
                        }
                }

                private void SelectNextPart()
                {
                        int selected_index;
                        if (is_checkbox_selected) {
                                for (int i = 0; i < part_data.Length; i++)
                                {
                                        if (!part_data[i].is_literal)
                                        {
                                                is_checkbox_selected = false;
                                                part_data[i].is_selected = true;
                                                Invalidate();
                                                break;
                                        }
                                }
                        } else {
                                selected_index = GetSelectedPartIndex();
                                if (selected_index >= 0)
                                        part_data[selected_index].is_selected = false;
                                for (int i = selected_index + 1; i < part_data.Length; i++)
                                {
                                        if (!part_data[i].is_literal)
                                        {
                                                part_data[i].is_selected = true;
                                                Invalidate();
                                                break;
                                        }
                                }
                                if (GetSelectedPartIndex() == -1)
                                { // if no part was found before the end, look from the beginning
                                        if (ShowCheckBox)
                                        {
                                                is_checkbox_selected = true;
                                                Invalidate();
                                        }
                                        else
                                        {
                                                for (int i = 0; i <= selected_index; i++)
                                                {
                                                        if (!part_data[i].is_literal)
                                                        {
                                                                part_data[i].is_selected = true;
                                                                Invalidate();
                                                                break;
                                                        }
                                                }
                                        }
                                }
                        }

                }

                private void SelectPreviousPart()
                {
                        if (is_checkbox_selected)
                        {
                                for (int i = part_data.Length - 1; i >= 0; i--)
                                {
                                        if (!part_data[i].is_literal)
                                        {
                                                is_checkbox_selected = false;
                                                part_data[i].is_selected = true;
                                                Invalidate();
                                                break;
                                        }
                                }
                        }
                        else
                        {
                                int selected_index = GetSelectedPartIndex();

                                if (selected_index >= 0)
                                        part_data[selected_index].is_selected = false;

                                for (int i = selected_index - 1; i >= 0; i--)
                                {
                                        if (!part_data[i].is_literal)
                                        {
                                                part_data[i].is_selected = true;
                                                Invalidate();
                                                break;
                                        }
                                }
                                if (GetSelectedPartIndex() == -1)
                                {       // if no part was found before the beginning, look from the end
                                        if (ShowCheckBox)
                                        {
                                                is_checkbox_selected = true;
                                                Invalidate();
                                        }
                                        else
                                        {
                                                for (int i = part_data.Length - 1; i >= selected_index; i--)
                                                {
                                                        if (!part_data[i].is_literal)
                                                        {
                                                                part_data[i].is_selected = true;
                                                                Invalidate();
                                                                break;
                                                        }
                                                }
                                        }
                                }
                        }
                }

                // raised by key down events.
                private void KeyDownHandler(object sender, KeyEventArgs e)
                {
                        switch (e.KeyCode)
                        {
                                case Keys.Add:
                                case Keys.Up:
                                        {
                                                if (ShowCheckBox && Checked == false)
                                                        break;
                                                IncrementSelectedPart(1);
                                                e.Handled = true;
                                                break;
                                        }
                                case Keys.Subtract:
                                case Keys.Down:
                                        {
                                                if (ShowCheckBox && Checked == false)
                                                        break;
                                                IncrementSelectedPart(-1);
                                                e.Handled = true;
                                                break;
                                        }
                                case Keys.Left:
                                        {// select the next part to the left
                                                if (ShowCheckBox && Checked == false)
                                                        break;
                                                SelectPreviousPart();
                                                e.Handled = true;
                                                break;
                                        }
                                case Keys.Right:
                                        {// select the next part to the right
                                                if (ShowCheckBox && Checked == false)
                                                        break;
                                                SelectNextPart();
                                                e.Handled = true;
                                                break;
                                        }
                                case Keys.F4:
                                        if (!is_drop_down_visible)
                                                DropDownMonthCalendar();
                                        break;
                        }
                }

                // raised by any key down events
                private void KeyPressHandler (object sender, KeyPressEventArgs e)
                {
                        switch (e.KeyChar) {
                                case ' ':
                                        if (is_checkbox_selected)
                                        {
                                                Checked = !Checked;
                                        }
                                        break;
                                case '0':
                                case '1':
                                case '2':
                                case '3':
                                case '4':
                                case '5':
                                case '6':
                                case '7':
                                case '8':
                                case '9':
                                        int number = e.KeyChar - (int) '0';
                                        int selected_index = GetSelectedPartIndex();
                                        if (selected_index == -1)
                                                break;
                                        if (!part_data[selected_index].is_numeric_format)
                                                break;
                                        switch (part_data[selected_index].value)
                                        {
                                                case "d":
                                                case "dd":
                                                        int newDay = Value.Day * 10 + number;
                                                        if (DateTime.DaysInMonth(Value.Year, Value.Month) < newDay)
                                                                newDay = number;
                                                        SetPart(newDay, 'd');
                                                        break;
                                                case "M":
                                                case "MM":
                                                        int newMonth = Value.Month * 10 + number;
                                                        if (newMonth > 12)
                                                                newMonth = number;
                                                        SetPart(newMonth, 'M');
                                                        break;
                                                case "y":
                                                case "yy":
                                                case "yyyy":
                                                        int newYear = Value.Year * 10 + number;
                                                        if (newYear > 9999)
                                                                newYear = number;
                                                        SetPart(newYear, 'y');
                                                        break;
                                                case "h":
                                                case "hh":
                                                case "H":
                                                case "HH":
                                                        int newHour = Value.Hour * 10 + number;
                                                        if (newHour >= 24)
                                                                newHour = number;
                                                        SetPart(newHour, 'h');
                                                        break;
                                                case "m":
                                                case "mm":
                                                        int newMinute = Value.Minute* 10 + number;
                                                        if (newMinute >= 60)
                                                                newMinute = number;
                                                        SetPart(newMinute, 'm');
                                                        break;
                                                case "s":
                                                case "ss":
                                                        int newSecond = Value.Second * 10 + number;
                                                        if (newSecond >= 60)
                                                                newSecond = number;
                                                        SetPart(newSecond, 's');
                                                        break;

                                        }
                                        break;
                                default:
                                        break;
                        }
                        e.Handled = true;
                }

                // set the specified part of the date to the specified value
                private void SetPart(int value, char part)
                {
                        switch (part)
                        {
                                case 's': // seconds
                                        value %= 60;
                                        if (value == -1)
                                                value = 59;
                                        if (value >= 0 && value <= 59)
                                                Value = new DateTime(Value.Year, Value.Month, Value.Day, Value.Hour, Value.Minute, value, Value.Millisecond);
                                        break;
                                case 'm': // minutes
                                        value %= 60;
                                        if (value == -1)
                                                value = 59;
                                        if (value >= 0 && value <= 59)
                                                Value = new DateTime(Value.Year, Value.Month, Value.Day, Value.Hour, value, Value.Second, Value.Millisecond);
                                        break;
                                case 'h':
                                case 'H': // hours
                                        value %= 24;
                                        if (value == -1)
                                                value = 23;
                                        if (value >= 0 && value <= 23)
                                                Value = new DateTime(Value.Year, Value.Month, Value.Day, value, Value.Minute, Value.Second, Value.Millisecond);
                                        break;
                                case 'd': // days
                                        int max_days = DateTime.DaysInMonth(Value.Year, Value.Month);
                                        if (value > max_days)
                                                Value = new DateTime(Value.Year, Value.Month, max_days, Value.Hour, Value.Minute, Value.Second, Value.Millisecond);
                                        if (value >= 1 && value <= 31)
                                                Value = new DateTime(Value.Year, Value.Month, value, Value.Hour, Value.Minute, Value.Second, Value.Millisecond);
                                        break;
                                case 'M': // months
                                        value %= 12;
                                        if (value == 0)
                                                value = 12;
                                        if (value >= 1 && value <= 12)
                                                Value = new DateTime(Value.Year, value, Value.Day, Value.Hour, Value.Minute, Value.Second, Value.Millisecond);
                                        break;
                                case 'y': // years
                                        value %= 10000;
                                        if (value > 0 && value <= 9999)
                                                Value = new DateTime(value, Value.Month, Value.Day, Value.Hour, Value.Minute, Value.Second, Value.Millisecond);
                                        break;
                        }
                }

                // if we loose focus deselect any selected parts.
                private void LostFocusHandler (object sender, EventArgs e) 
                {
                        int selected_index = GetSelectedPartIndex ();
                        if (selected_index != -1)
                        {
                                part_data [selected_index].is_selected = false;
                                Rectangle invalidate_rect = Rectangle.Ceiling (part_data [selected_index].drawing_rectangle);
                                invalidate_rect.Inflate (2, 2);
                                Invalidate (invalidate_rect);
                        }
                        else if (is_checkbox_selected)
                        {
                                is_checkbox_selected = false;
                                Invalidate (CheckBoxRect);
                        }
                }

                // if month calendar looses focus and the drop down is up, then close it
                private void MonthCalendarLostFocusHandler(object sender, EventArgs e)
                {
                        if (is_drop_down_visible && !month_calendar.Focused)
                        {
                                //this.HideMonthCalendar(); 
                                //This is handled from the monthcalender itself, 
                                //it may loose focus, but still has to be visible,
                                //for instance when the context menu is displayed.
                        }

                }

                private void MonthCalendarDateChangedHandler (object sender, DateRangeEventArgs e)
                {
                        if (month_calendar.Visible)
                                this.Value = e.Start.Date.Add (this.Value.TimeOfDay);
                }

                // fired when a user clicks on the month calendar to select a date
                private void MonthCalendarDateSelectedHandler (object sender, DateRangeEventArgs e)
                {
                        this.HideMonthCalendar ();      
                        this.Focus ();                  
                } 

                private void MouseUpHandler(object sender, MouseEventArgs e)
                {
                        if (ShowUpDown)
                        {
                                if (is_up_pressed || is_down_pressed)
                                {
                                        updown_timer.Enabled = false;
                                        is_up_pressed = false;
                                        is_down_pressed = false;
                                        Invalidate (drop_down_arrow_rect);
                                }
                        }
                }

                // to check if the mouse has come down on this control
                private void MouseDownHandler (object sender, MouseEventArgs e)
                {
                        // Only left clicks are handled.
                        if (e.Button != MouseButtons.Left)
                                return;

                        is_checkbox_selected = false;

                        if (ShowCheckBox && CheckBoxRect.Contains(e.X, e.Y))
                        {
                                is_checkbox_selected = true;
                                Checked = !Checked;
                                return;
                        }


                        if (ShowUpDown && drop_down_arrow_rect.Contains (e.X, e.Y))
                        {
                                if (!(ShowCheckBox && Checked == false))
                                {
                                        if (e.Y < this.Height / 2) {
                                                is_up_pressed = true;
                                                is_down_pressed = false;
                                                IncrementSelectedPart (1);
                                        } else {
                                                is_up_pressed = false;
                                                is_down_pressed = true;
                                                IncrementSelectedPart (-1);
                                        }
                                        Invalidate (drop_down_arrow_rect);
                                        updown_timer.Interval = initial_timer_delay;
                                        updown_timer.Enabled = true;
                                }
                        } else if (is_drop_down_visible == false && drop_down_arrow_rect.Contains (e.X, e.Y)) {
                                is_drop_down_visible = true;
                                if (!Checked)
                                        Checked = true;
                                Invalidate (drop_down_arrow_rect);
                                DropDownMonthCalendar ();
                        } else {
                                // mouse down on this control anywhere else collapses it
                                if (is_drop_down_visible) {                             
                                        HideMonthCalendar ();
                                        this.Focus ();
                                }
                                if (!(ShowCheckBox && Checked == false))
                                {
                                        // go through the parts to see if the click is in any of them
                                        bool invalidate_afterwards = false;
                                        for (int i = 0; i < part_data.Length; i++) {
                                                bool old = part_data [i].is_selected;

                                                if (part_data [i].is_literal)
                                                        continue;

                                                if (part_data [i].drawing_rectangle.Contains (e.X, e.Y)) {
                                                        part_data [i].is_selected = true;
                                                } else {
                                                        part_data [i].is_selected = false;
                                                }
                                                if (old != part_data [i].is_selected) 
                                                        invalidate_afterwards = true;
                                        }
                                        if (invalidate_afterwards)
                                                Invalidate ();
                                }
                                
                        }
                }
                
                
                // paint this control now
                private void PaintHandler (object sender, PaintEventArgs pe) {
                        if (Width <= 0 || Height <=  0 || Visible == false)
                                return;

                        Draw (pe.ClipRectangle, pe.Graphics);
                }
                
                #endregion              

                #region internal classes
                internal class PartData
                {
                        internal string value;
                        internal bool is_literal;
                        internal bool is_selected;
                        internal RectangleF drawing_rectangle;

                        internal bool is_numeric_format
                        {
                                get
                                {
                                        if (is_literal)
                                                return false;
                                        switch (value) {
                                        case "m":
                                        case "mm":
                                        case "d":
                                        case "dd":
                                        case "h":
                                        case "hh":
                                        case "H":
                                        case "HH":
                                        case "M":
                                        case "MM":
                                        case "s":
                                        case "ss":
                                        case "y":
                                        case "yy":
                                        case "yyyy":
                                                return true;
                                        case "ddd":
                                        case "dddd":
                                                return false;
                                        default:
                                                return false;
                                        }
                                }
                        }

                        internal PartData(string value, bool is_literal)
                        {
                                this.value = value;
                                this.is_literal = is_literal;
                        }

                        // calculate the string to show for this data
                        internal string GetText(DateTime date)
                        {
                                if (is_literal) {
                                        return value;
                                } else {
                                        return GetText (date, value);
                                }
                        }

                        static internal string GetText(DateTime date, string format)
                        {
                                if (format.StartsWith ("g")) 
                                        return " ";
                                else if (format.Length == 1)
                                        return date.ToString ("%" + format);
                                else
                                        return date.ToString (format);
                        }
                }
                
                #endregion              
        }
}