//------------------------------------------------------------------------------
// <copyright file="ScrollBarRenderer.cs" company="Microsoft">
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// </copyright>                                                                
//------------------------------------------------------------------------------
namespace System.Windows.Forms { 
 
using System;
using System.Drawing;
using System.Windows.Forms.VisualStyles;
using System.Diagnostics.CodeAnalysis;
using Microsoft.Win32;
 
    /// <include file='doc\ScrollBarRenderer.uex' path='docs/doc[@for="ScrollBarRenderer"]/*' />
    /// <devdoc>
    ///    <para>
    ///       This is a rendering class for the ScrollBar control.
    ///    </para>
    /// </devdoc>
    public sealed class ScrollBarRenderer {
 
       //Make this per-thread, so that different threads can safely use these methods.
       [ThreadStatic]
       private static VisualStyleRenderer visualStyleRenderer = null;
       
        //cannot instantiate
       private ScrollBarRenderer() {
       }
 
       /// <include file='doc\ScrollBarRenderer.uex' path='docs/doc[@for="ScrollBarRenderer.IsSupported"]/*' />
       /// <devdoc>
       ///    <para>
       ///       Returns true if this class is supported for the current OS and user/application settings, 
       ///       otherwise returns false.
       ///    </para>
       /// </devdoc>
       public static bool IsSupported {
           get {
               return VisualStyleRenderer.IsSupported; // no downlevel support
           }
       }
 
       /// <include file='doc\ScrollBarRenderer.uex' path='docs/doc[@for="ScrollBarRenderer.DrawArrowButton"]/*' />
       /// <devdoc>
       ///    <para>
       ///       Renders a ScrollBar arrow button.
       ///    </para>
       /// </devdoc>
       [SuppressMessage("Microsoft.Design", "CA1011:ConsiderPassingBaseTypesAsParameters")] // Using Graphics instead of IDeviceContext intentionally
       public static void DrawArrowButton(Graphics g, Rectangle bounds, ScrollBarArrowButtonState state) {
           InitializeRenderer(VisualStyleElement.ScrollBar.ArrowButton.LeftNormal, (int)state);
 
           visualStyleRenderer.DrawBackground(g, bounds);
       }
 
       /// <include file='doc\ScrollBarRenderer.uex' path='docs/doc[@for="ScrollBarRenderer.DrawHorizontalThumb"]/*' />
       /// <devdoc>
       ///    <para>
       ///       Renders a horizontal ScrollBar thumb.
       ///    </para>
       /// </devdoc>
       [SuppressMessage("Microsoft.Design", "CA1011:ConsiderPassingBaseTypesAsParameters")] // Using Graphics instead of IDeviceContext intentionally
       public static void DrawHorizontalThumb(Graphics g, Rectangle bounds, ScrollBarState state) {
           InitializeRenderer(VisualStyleElement.ScrollBar.ThumbButtonHorizontal.Normal, (int)state);
 
           visualStyleRenderer.DrawBackground(g, bounds);
       }
 
              /// <include file='doc\ScrollBarRenderer.uex' path='docs/doc[@for="ScrollBarRenderer.DrawVerticalThumb"]/*' />
       /// <devdoc>
       ///    <para>
       ///       Renders a vertical ScrollBar thumb.
       ///    </para>
       /// </devdoc>
       [SuppressMessage("Microsoft.Design", "CA1011:ConsiderPassingBaseTypesAsParameters")] // Using Graphics instead of IDeviceContext intentionally
       public static void DrawVerticalThumb(Graphics g, Rectangle bounds, ScrollBarState state) {
           InitializeRenderer(VisualStyleElement.ScrollBar.ThumbButtonVertical.Normal, (int)state);
 
           visualStyleRenderer.DrawBackground(g, bounds);
       }
 
       /// <include file='doc\ScrollBarRenderer.uex' path='docs/doc[@for="ScrollBarRenderer.DrawHorizontalThumbGrip"]/*' />
       /// <devdoc>
       ///    <para>
       ///       Renders a horizontal ScrollBar thumb grip.
       ///    </para>
       /// </devdoc>
       [SuppressMessage("Microsoft.Design", "CA1011:ConsiderPassingBaseTypesAsParameters")] // Using Graphics instead of IDeviceContext intentionally
       public static void DrawHorizontalThumbGrip(Graphics g, Rectangle bounds, ScrollBarState state) {
           InitializeRenderer(VisualStyleElement.ScrollBar.GripperHorizontal.Normal, (int)state);
 
           visualStyleRenderer.DrawBackground(g, bounds);
       }
 
       /// <include file='doc\ScrollBarRenderer.uex' path='docs/doc[@for="ScrollBarRenderer.DrawVerticalThumbGrip"]/*' />
       /// <devdoc>
       ///    <para>
       ///       Renders a vertical ScrollBar thumb grip.
       ///    </para>
       /// </devdoc>
       [SuppressMessage("Microsoft.Design", "CA1011:ConsiderPassingBaseTypesAsParameters")] // Using Graphics instead of IDeviceContext intentionally
       public static void DrawVerticalThumbGrip(Graphics g, Rectangle bounds, ScrollBarState state) {
           InitializeRenderer(VisualStyleElement.ScrollBar.GripperVertical.Normal, (int)state);
 
           visualStyleRenderer.DrawBackground(g, bounds);
       }
 
       /// <include file='doc\ScrollBarRenderer.uex' path='docs/doc[@for="ScrollBarRenderer.DrawRightHorizontalTrack"]/*' />
       /// <devdoc>
       ///    <para>
       ///       Renders a horizontal ScrollBar thumb.
       ///    </para>
       /// </devdoc>
       [SuppressMessage("Microsoft.Design", "CA1011:ConsiderPassingBaseTypesAsParameters")] // Using Graphics instead of IDeviceContext intentionally
       public static void DrawRightHorizontalTrack(Graphics g, Rectangle bounds, ScrollBarState state) {
           InitializeRenderer(VisualStyleElement.ScrollBar.RightTrackHorizontal.Normal, (int)state);
 
           visualStyleRenderer.DrawBackground(g, bounds);
       }
 
       /// <include file='doc\ScrollBarRenderer.uex' path='docs/doc[@for="ScrollBarRenderer.DrawLeftHorizontalTrack"]/*' />
       /// <devdoc>
       ///    <para>
       ///       Renders a horizontal ScrollBar thumb.
       ///    </para>
       /// </devdoc>
       [SuppressMessage("Microsoft.Design", "CA1011:ConsiderPassingBaseTypesAsParameters")] // Using Graphics instead of IDeviceContext intentionally
       public static void DrawLeftHorizontalTrack(Graphics g, Rectangle bounds, ScrollBarState state) {
           InitializeRenderer(VisualStyleElement.ScrollBar.LeftTrackHorizontal.Normal, (int)state);
 
           visualStyleRenderer.DrawBackground(g, bounds);
       }
              
       /// <include file='doc\ScrollBarRenderer.uex' path='docs/doc[@for="ScrollBarRenderer.DrawUpperVerticalTrack"]/*' />
       /// <devdoc>
       ///    <para>
       ///       Renders a vertical ScrollBar thumb in the center of the given bounds.
       ///    </para>
       /// </devdoc>
       [SuppressMessage("Microsoft.Design", "CA1011:ConsiderPassingBaseTypesAsParameters")] // Using Graphics instead of IDeviceContext intentionally
       public static void DrawUpperVerticalTrack(Graphics g, Rectangle bounds, ScrollBarState state) {
           InitializeRenderer(VisualStyleElement.ScrollBar.UpperTrackVertical.Normal, (int)state);
 
           visualStyleRenderer.DrawBackground(g, bounds);
       }
 
       /// <include file='doc\ScrollBarRenderer.uex' path='docs/doc[@for="ScrollBarRenderer.DrawLowerVerticalTrack"]/*' />
       /// <devdoc>
       ///    <para>
       ///       Renders a vertical ScrollBar thumb in the center of the given bounds.
       ///    </para>
       /// </devdoc>
       [SuppressMessage("Microsoft.Design", "CA1011:ConsiderPassingBaseTypesAsParameters")] // Using Graphics instead of IDeviceContext intentionally
       public static void DrawLowerVerticalTrack(Graphics g, Rectangle bounds, ScrollBarState state) {
           InitializeRenderer(VisualStyleElement.ScrollBar.LowerTrackVertical.Normal, (int)state);
 
           visualStyleRenderer.DrawBackground(g, bounds);
       }
 
       /// <include file='doc\ScrollBarRenderer.uex' path='docs/doc[@for="ScrollBarRenderer.DrawSizeBox"]/*' />
       /// <devdoc>
       ///    <para>
       ///       Renders a ScrollBar size box in the center of the given bounds.
       ///    </para>
       /// </devdoc>
       [SuppressMessage("Microsoft.Design", "CA1011:ConsiderPassingBaseTypesAsParameters")] // Using Graphics instead of IDeviceContext intentionally
       public static void DrawSizeBox(Graphics g, Rectangle bounds, ScrollBarSizeBoxState state) {
           InitializeRenderer(VisualStyleElement.ScrollBar.SizeBox.LeftAlign, (int)state);
 
           visualStyleRenderer.DrawBackground(g, bounds);
       }
 
       /// <include file='doc\ScrollBarRenderer.uex' path='docs/doc[@for="ScrollBarRenderer.GetThumbGripSize"]/*' />
       /// <devdoc>
       ///    <para>
       ///       Returns the size of the ScrollBar thumb grip.
       ///    </para>
       /// </devdoc>
       [SuppressMessage("Microsoft.Design", "CA1011:ConsiderPassingBaseTypesAsParameters")] // Using Graphics instead of IDeviceContext intentionally
       public static Size GetThumbGripSize(Graphics g, ScrollBarState state) {
           InitializeRenderer(VisualStyleElement.ScrollBar.GripperHorizontal.Normal, (int)state);
 
           return visualStyleRenderer.GetPartSize(g, ThemeSizeType.True);
       }
 
       /// <include file='doc\ScrollBarRenderer.uex' path='docs/doc[@for="ScrollBarRenderer.GetSizeBoxSize"]/*' />
       /// <devdoc>
       ///    <para>
       ///       Returns the size of the ScrollBar size box.
       ///    </para>
       /// </devdoc>
       [SuppressMessage("Microsoft.Design", "CA1011:ConsiderPassingBaseTypesAsParameters")] // Using Graphics instead of IDeviceContext intentionally
       public static Size GetSizeBoxSize(Graphics g, ScrollBarState state) {
           InitializeRenderer(VisualStyleElement.ScrollBar.SizeBox.LeftAlign, (int)state);
 
           return visualStyleRenderer.GetPartSize(g, ThemeSizeType.True);
       }
 
       private static void InitializeRenderer(VisualStyleElement element, int state) {
           if (visualStyleRenderer == null) {
               visualStyleRenderer = new VisualStyleRenderer(element.ClassName, element.Part, state);
           }
           else {
               visualStyleRenderer.SetParameters(element.ClassName, element.Part, state);
           }
       }
    }
}