using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Drawing.Drawing2D;
using System.Threading;

namespace TemuKJD.UserComponent
{
    /// <summary>
    /// 基于树视图的任务控件
    /// </summary>
    public partial class UcTreeView : TreeView
    {
        #region //construckor
        /// <summary>
        /// 自定义树视图控件构造函数
        /// </summary>
        public UcTreeView()
        {
            FullRowSelect = true;
            ShowLines = true;
            // 开启双缓冲等
            this.SetStyle(ControlStyles.OptimizedDoubleBuffer | ControlStyles.EnableNotifyMessage | ControlStyles.ResizeRedraw | ControlStyles.AllPaintingInWmPaint, true);
            this.DrawMode = TreeViewDrawMode.OwnerDrawAll;
            this.ItemHeight = 32;
            this.ShowLines = true;
            this.AfterExpand += UserTreeView_AfterExpand;
            this.AfterSelect += UserTreeView_AfterSelect;
            this.Layout += UserTreeView_Layout;
            if (Properties.Resources.ResourceManager.GetObject("tree_default_icon_select") != null)
                defaultNodeImageSelect = (Bitmap)Properties.Resources.ResourceManager.GetObject("tree_default_icon_select");
            if (Properties.Resources.ResourceManager.GetObject("tree_default_icon") != null)
                defaultNodeImage = (Bitmap)Properties.Resources.ResourceManager.GetObject("tree_default_icon");
        }

        protected override void OnNotifyMessage(Message m)
        {
            if (m.Msg != 0x14)
            {
                base.OnNotifyMessage(m);
            }
        }

        protected override CreateParams CreateParams
        {
            get
            {
                CreateParams cp = base.CreateParams;
                cp.ExStyle |= 0x02000000;
                return cp;
            }
        }

        private void UserTreeView_AfterSelect(object sender, TreeViewEventArgs e)
        {
            if (e.Node.Parent != null)
                dicSelectNodeId[e.Node.Parent] = e.Node;
        }
        #endregion

        #region //event
        // 定义委托
        public delegate void NodeGroupClickHandle(object sender, TreeViewEventArgs e);

        // 定义事件
        public event NodeGroupClickHandle NodeGroupClick;

        // 执行事件
        protected virtual void OnNodeGroupClick(TreeViewEventArgs e)
        {
            if (NodeGroupClick != null)
            {
                NodeGroupClick(this, e);
            }
        }

        private void UserTreeView_Layout(object sender, LayoutEventArgs e)
        {
            if (!DesignMode)
            {
                foreach (TreeNode node in this.Nodes)
                {
                    if (node != null)
                    {
                        if (allNodes.Contains(node) == false)
                            allNodes.Add(node);
                    }
                    foreach (TreeNode childNode in node.Nodes)
                    {
                        if (node == null)
                            continue;
                        if (!dicNodeImageSelect.Keys.Contains(childNode))
                        {
                            // 获取图标
                            if (Properties.Resources.ResourceManager.GetObject("tree_" + childNode.Text + "_select") != null)
                            {
                                var bitmap = (Bitmap)Properties.Resources.ResourceManager.GetObject("tree_" + childNode.Text + "_select");
                                dicNodeImageSelect[childNode] = bitmap;
                            }
                        }
                        if (!dicNodeImage.Keys.Contains(childNode))
                        {
                            // 获取图标
                            if (Properties.Resources.ResourceManager.GetObject("tree_" + childNode.Text) != null)
                            {
                                var bitmap = (Bitmap)Properties.Resources.ResourceManager.GetObject("tree_" + childNode.Text);
                                dicNodeImage[childNode] = bitmap;
                            }
                        }
                    }
                }
            }
        }

        private void UserTreeView_AfterExpand(object sender, TreeViewEventArgs e)
        {
            BeginUpdate();
            if (HideCollapsedGroup && !DesignMode)
            {
                for (int i = 0; i < this.Nodes.Count; i++)
                {
                    if (e.Node != this.Nodes[i])
                    {
                        this.Nodes.Remove(this.Nodes[i]);
                        i--;
                    }
                }
            }

            foreach (TreeNode node in this.AllNodes)
            {
                if (node == null)
                    continue;

                if (node != e.Node)
                {
                    node.Collapse(true);
                }
                else
                {
                    if (this.SelectedNode == null || this.SelectedNode.Parent == node)
                        continue;
                    else if (dicSelectNodeId.Keys.Contains(node))
                        this.SelectedNode = dicSelectNodeId[node];
                    else if (node.Nodes.Count > 0)
                        this.SelectedNode = node.Nodes[0];
                }
            }
            EndUpdate();
        }
        #endregion

        #region //field & property
        private Bitmap defaultNodeImage;
        private Bitmap defaultNodeImageSelect;
        private List<TreeNode> lstTreeNode = new List<TreeNode>();
        private Dictionary<TreeNode, TreeNode> dicSelectNodeId = new Dictionary<TreeNode, TreeNode>();
        private Dictionary<TreeNode, Bitmap> dicNodeImage = new Dictionary<TreeNode, Bitmap>();
        private Dictionary<TreeNode, Bitmap> dicNodeImageSelect = new Dictionary<TreeNode, Bitmap>();
        /// <summary>
        /// 展开按扭的大小
        /// </summary>
        private Size ExpandButtonSize = new Size(16, 16);
        private Color _ExpandButtonColor = Color.FromArgb(255, 255, 255);
        /// <summary>
        /// 展开按扭颜色
        /// </summary>
        [Description("展开按扭颜色"), Category("UserProperty")]
        public Color ExpandButtonColor
        {
            get
            {
                return _ExpandButtonColor;
            }
            set
            {
                if (_ExpandButtonColor != value)
                {
                    _ExpandButtonColor = value;
                    this.Invalidate();
                }
            }
        }
        private Color _GroupBgColor = Color.FromArgb(249, 249, 249);
        /// <summary>
        /// 分组栏背景色
        /// </summary>
        [Description("分组栏背景色"), Category("UserProperty")]
        public Color GroupBgColor
        {
            get
            {
                return _GroupBgColor;
            }
            set
            {
                if (_GroupBgColor != value)
                {
                    _GroupBgColor = value;
                    this.Invalidate();
                }
            }
        }

        private Color _ChildNodeSelectedBgColor = Color.FromArgb(34, 148, 203);
        /// <summary>
        /// 子节点选中背景色
        /// </summary>
        [Description("子节点选中背景色"), Category("UserProperty")]
        public Color ChildNodeSelectedBgColor
        {
            get
            {
                return this._ChildNodeSelectedBgColor;
            }
            set
            {
                if (_ChildNodeSelectedBgColor != value)
                {
                    _ChildNodeSelectedBgColor = value;
                    this.Invalidate();
                }
            }
        }

        private Color _GroupTitleColor = Color.FromArgb(80, 80, 80);
        /// <summary>
        /// 分组栏标题色
        /// </summary>
        [Description("分组栏标题色"), Category("UserProperty")]
        public Color GroupTitleColor
        {
            get
            {
                return _GroupTitleColor;
            }
            set
            {
                if (_GroupTitleColor != value)
                {
                    _GroupTitleColor = value;
                    this.Invalidate();
                }
            }
        }

        private Color _OverForeColor = Color.FromArgb(235, 235, 235);
        /// <summary>
        /// 鼠标悬停色
        /// </summary>
        [Description("鼠标悬停色"), Category("UserProperty")]
        public Color OverForeColor
        {
            get
            {
                return _OverForeColor;
            }
            set
            {
                if (_OverForeColor != value)
                {
                    _OverForeColor = value;
                    this.Invalidate();
                }
            }
        }

        private Font groupFont = new Font("宋体", 10.5f);
        /// <summary>
        /// 组标题字体样式
        /// </summary>
        [Description("组标题字体样式"), Category("UserProperty")]
        public Font GroupFont
        {
            get
            {
                return groupFont;
            }
            set
            {
                if (groupFont != value)
                {
                    groupFont = value;
                    this.Invalidate();
                }
            }
        }

        private bool _HideCollpasedGroup = false;
        [Description("隐藏折叠的组"), Category("UserProperty")]
        public bool HideCollapsedGroup
        {
            get
            {
                return _HideCollpasedGroup;
            }
            set
            {
                if (_HideCollpasedGroup != value)
                {
                    _HideCollpasedGroup = value;
                    this.Invalidate();
                }
            }
        }

        /// <summary>
        /// 节点高度
        /// </summary>
        public new int ItemHeight
        {
            get
            {
                return base.ItemHeight;
            }
            set
            {
                if (base.ItemHeight != value && value >= 20)
                {
                    base.ItemHeight = value;
                    this.Invalidate();
                }
            }
        }

        private List<TreeNode> allNodes = new List<TreeNode>();
        /// <summary>
        /// 所有节点列表
        /// </summary>
        public List<TreeNode> AllNodes { get { return allNodes; } }

        #endregion

        #region //override
        protected override void OnDrawNode(DrawTreeNodeEventArgs e)
        {
            //base.OnDrawNode(e);
            DrawNodeItem(e);
        }
        protected override void WndProc(ref Message m)
        {
            if (m.Msg == 0x0201)//单击
            {
                int wparam = m.LParam.ToInt32();
                Point point = new Point(
                    LOWORD(wparam),
                    HIWORD(wparam));
                //point = PointToClient(point);
                TreeNode tn = this.GetNodeAt(point);
                if (tn == null)
                {
                    base.WndProc(ref m);
                    return;
                }
                if (tn.Level == 0)
                {
                    if (tn.IsExpanded)
                    {
                        //tn.Collapse();
                    }
                    else
                    {
                        tn.Expand();
                    }
                    m.Result = IntPtr.Zero;
                    OnNodeGroupClick(new TreeViewEventArgs(tn, TreeViewAction.ByMouse));
                    return;
                }
                else
                {
                    base.WndProc(ref m);
                    //tn.IsSelected = true;
                    //this.SelectedNode = tn;
                }
                this.SelectedNode = tn;
            }
            else if (m.Msg == 0x0203)//双击
            {
                int wparam = m.LParam.ToInt32();
                Point point = new Point(
                    LOWORD(wparam),
                    HIWORD(wparam));
                //point = PointToClient(point);
                TreeNode tn = this.GetNodeAt(point);
                if (tn == null)
                {
                    base.WndProc(ref m);
                    return;
                }
                if (tn.Level == 0)
                {
                    m.Result = IntPtr.Zero;
                    return;
                }
                else
                {
                    base.WndProc(ref m);
                }
                this.SelectedNode = tn;
            }
            else if (m.Msg == 0x0200)//鼠标移动
            {
                try
                {
                    int wparam = m.LParam.ToInt32();
                    Point point = new Point(
                        LOWORD(wparam),
                        HIWORD(wparam));
                    //point = PointToClient(point);
                    TreeNode tn = this.GetNodeAt(point);
                    if (tn == null)
                    {
                        Cursor = Cursors.Default;
                        // this.SelectedNode = null;
                        base.WndProc(ref m);
                        return;
                    }
                    Cursor = Cursors.Hand;
                    //this.SelectedNode = tn;
                }
                catch { }
            }
            else if (m.Msg == 0x02A3)//鼠标移出 WM_MOUSELEAVE = $02A3;
            {
                // this.SelectedNode = null;
                base.WndProc(ref m);
                return;
            }
            else
            {
                base.WndProc(ref m);
            }
            //WM_LBUTTONDOWN = $0201
            //WM_LBUTTONDBLCLK = $0203;
        }
        #endregion

        #region //private method
        /// <summary>
        /// 自定义绘制节点
        /// </summary>
        /// <param name="e"></param>
        private void DrawNodeItem(DrawTreeNodeEventArgs e)
        {
            TreeNode tn = e.Node;
            if (tn.Level == 0)
            {
                using (Graphics g = e.Graphics)
                {
                    //g.Clear(this.BackColor); // 清空画布，完整重绘时才能使用
                    //g.SmoothingMode = SmoothingMode.HighQuality; // 高质量
                    //g.PixelOffsetMode = PixelOffsetMode.HighQuality; // 高像素偏移质量
                    //绘制分组的背景
                    //RenderBackgroundInternalRate(g,
                    //    e.Bounds,
                    //    GroupBgColor,
                    //    GroupBgColor,
                    //    Color.FromArgb(200, 255, 255, 255),
                    //    0.45f,
                    //    true,
                    //    300);
                    int red = GroupBgColor.R;
                    int green = GroupBgColor.G;
                    int blue = GroupBgColor.B;
                    if (red < 127) red += 15; else red -= 15;
                    if (green < 127) green += 15; else green -= 15;
                    if (blue < 127) blue += 15; else blue -= 15;
                    var color = Color.FromArgb(red, green, blue);
                    RenderBackgroundSolid(g, e.Bounds, color, color, color, false);
                    //绘制展开按扭
                    //g.FillEllipse(new SolidBrush(ExpandButtonColor), ExpandButtonBounds(e.Bounds));
                    //g.DrawEllipse(new Pen(Color.LightGray), ExpandButtonBounds(e.Bounds));
                    //Point p1;
                    //Point p2;
                    //Point p3;
                    //if (tn.IsExpanded)
                    //{
                    //    p1 = new Point(ExpandButtonBounds(e.Bounds).X + 3, ExpandButtonBounds(e.Bounds).Bottom - 4);
                    //    p2 = new Point(ExpandButtonBounds(e.Bounds).X + (ExpandButtonSize.Width) / 2, ExpandButtonBounds(e.Bounds).Top + 5);
                    //    p3 = new Point(ExpandButtonBounds(e.Bounds).Right - 3, ExpandButtonBounds(e.Bounds).Bottom - 4);
                    //}
                    //else
                    //{
                    //    p1 = new Point(ExpandButtonBounds(e.Bounds).X + 3, ExpandButtonBounds(e.Bounds).Y + 4);
                    //    p2 = new Point(ExpandButtonBounds(e.Bounds).X + (ExpandButtonSize.Width) / 2, ExpandButtonBounds(e.Bounds).Bottom - 5);
                    //    p3 = new Point(ExpandButtonBounds(e.Bounds).Right - 3, ExpandButtonBounds(e.Bounds).Y + 4);
                    //}
                    //GraphicsPath gp = new GraphicsPath();
                    //gp.AddLine(p1, p2);
                    //gp.AddLine(p2, p3);
                    //g.DrawPath(new Pen(Color.FromArgb(255, 150, 0, 0), 2f), gp);

                    //绘制分组的文本
                    TextRenderer.DrawText(g, e.Node.Text, this.GroupFont, GroupTitleBounds(e.Bounds), this.GroupTitleColor,
                        TextFormatFlags.Left | TextFormatFlags.VerticalCenter | TextFormatFlags.EndEllipsis);
                }
            }
            else if (tn.Level == 1)
            {
                //e.DrawDefault = true;

                using (Graphics g = e.Graphics)
                {
                    #region  小奶猫增加权限后，无法自动绘制TreeNode图标，经调试确认，增加此段代码 by ttzhao 2020.7.1
                    if (!dicNodeImageSelect.Keys.Contains(e.Node))
                    {
                        // 获取图标
                        if (Properties.Resources.ResourceManager.GetObject(e.Node.Text + "_select") != null)
                        {
                            var bitmap = (Bitmap)Properties.Resources.ResourceManager.GetObject(e.Node.Text + "_select");
                            dicNodeImageSelect[e.Node] = bitmap;
                        }
                    }
                    if (!dicNodeImage.Keys.Contains(e.Node))
                    {
                        // 获取图标
                        if (Properties.Resources.ResourceManager.GetObject(e.Node.Text) != null)
                        {
                            var bitmap = (Bitmap)Properties.Resources.ResourceManager.GetObject(e.Node.Text);
                            dicNodeImage[e.Node] = bitmap;
                        }
                    }
                    #endregion 小奶猫增加权限后，无法自动绘制TreeNode图标，经调试确认，增加此段代码 by ttzhao 2020.7.1

                    if (tn.IsSelected)
                    {
                        RenderBackgroundSolid(g, e.Bounds, ChildNodeSelectedBgColor, ChildNodeSelectedBgColor, ChildNodeSelectedBgColor, false);
                        //TextRenderer.DrawText(g, e.Node.Text, new Font(this.Font.FontFamily.Name, this.Font.Size, FontStyle.Underline), e.Bounds, OverForeColor, TextFormatFlags.Left | TextFormatFlags.VerticalCenter);
                        TextRenderer.DrawText(g, e.Node.Text, this.Font, ChildTitleBounds(e.Bounds), this.OverForeColor,
                            TextFormatFlags.Left | TextFormatFlags.VerticalCenter);

                        // 绘制图标
                        if (dicNodeImageSelect.Keys.Contains(e.Node))
                            g.DrawImage(dicNodeImageSelect[e.Node], new Rectangle(e.Bounds.X + 30, e.Bounds.Y + 8, 16, 16));
                        else if (defaultNodeImageSelect != null)
                            g.DrawImage(defaultNodeImageSelect, new Rectangle(e.Bounds.X + 30, e.Bounds.Y + 8, 16, 16));
                    }
                    else
                    {
                        RenderBackgroundSolid(g, e.Bounds, GroupBgColor, GroupBgColor, GroupBgColor, false);
                        //TextRenderer.DrawText(g, e.Node.Text, this.Font, e.Bounds, this.ForeColor, TextFormatFlags.Left | TextFormatFlags.VerticalCenter);
                        TextRenderer.DrawText(g, e.Node.Text, this.Font, ChildTitleBounds(e.Bounds), this.ForeColor,
                            TextFormatFlags.Left | TextFormatFlags.VerticalCenter);

                        // 绘制图标
                        if (dicNodeImage.Keys.Contains(e.Node))
                            g.DrawImage(dicNodeImage[e.Node], new Rectangle(e.Bounds.X + 30, e.Bounds.Y + 8, 16, 16));
                        else if (defaultNodeImage != null)
                            g.DrawImage(defaultNodeImage, new Rectangle(e.Bounds.X + 30, e.Bounds.Y + 8, 16, 16));
                    }
                }
            }
        }
        /// <summary>
        /// 展开按扭区域  一级菜单后面的展开按钮
        /// </summary>
        /// <param name="childRect"></param>
        /// <returns></returns>
        private Rectangle ExpandButtonBounds(Rectangle childRect)
        {
            Rectangle lrect = new Rectangle(new Point(childRect.Right - ExpandButtonSize.Width * 3 / 2, (childRect.Height - ExpandButtonSize.Height) / 2 + childRect.Top), ExpandButtonSize);
            return lrect;
        }
        /// <summary>
        /// 取得分组标题绘制空间  一级菜单
        /// </summary>
        /// <param name="childRect"></param>
        /// <returns></returns>
        private Rectangle GroupTitleBounds(Rectangle childRect)
        {
            Rectangle lrect = childRect;
            lrect.Width -= ExpandButtonSize.Width * 3 / 2 + 20;
            //lrect.Offset(45, 0);
            lrect.Offset(12, 0);
            return lrect;
        }
        private Rectangle ChildTitleBounds(Rectangle rect)
        {
            Rectangle lrect = rect;
            lrect.Width -= 50;
            lrect.Offset(55, 0);
            return lrect;
        }
        #endregion

        #region //draw
        internal void RenderBackgroundSolid(Graphics g, Rectangle rect, Color baseColor, Color borderColor, Color innerBorderColor, bool drawBorder)
        {
            if (drawBorder)
            {
                rect.Width--;
                rect.Height--;
            }
            using (SolidBrush brush = new SolidBrush(baseColor))
            {
                g.FillRectangle(brush, rect);
            }
            if (drawBorder)
            {
                using (Pen pen = new Pen(borderColor))
                {
                    g.DrawRectangle(pen, rect);
                }
                rect.Inflate(-1, -1);
                using (Pen pen = new Pen(innerBorderColor))
                {
                    g.DrawRectangle(pen, rect);
                }
            }
        }

        internal void RenderBackgroundInternal(Graphics g, Rectangle rect, Color baseColor, Color borderColor, Color innerBorderColor,
            float basePosition, bool drawBorder, LinearGradientMode mode)
        {
            if (drawBorder)
            {
                rect.Width--;
                rect.Height--;
            }
            using (LinearGradientBrush brush = new LinearGradientBrush(rect, Color.Transparent, Color.Transparent, mode))
            {
                Color[] colors = new Color[4];
                colors[0] = GetColor(baseColor, 0, 35, 24, 9);
                colors[1] = GetColor(baseColor, 0, 13, 8, 3);
                colors[2] = baseColor;
                colors[3] = GetColor(baseColor, 0, 68, 69, 54);
                ColorBlend blend = new ColorBlend();
                blend.Positions = new float[] { 0.0f, basePosition, basePosition + 0.05f, 1.0f };
                blend.Colors = colors;
                brush.InterpolationColors = blend;
                g.FillRectangle(brush, rect);
            }
            if (baseColor.A > 80)
            {
                Rectangle rectTop = rect;
                if (mode == LinearGradientMode.Vertical)
                {
                    rectTop.Height = (int)(rectTop.Height * basePosition);
                }
                else
                {
                    rectTop.Width = (int)(rect.Width * basePosition);
                }
                using (SolidBrush brushAlpha =
                    new SolidBrush(Color.FromArgb(80, 255, 255, 255)))
                {
                    g.FillRectangle(brushAlpha, rectTop);
                }
            }
            if (drawBorder)
            {
                using (Pen pen = new Pen(borderColor))
                {
                    g.DrawRectangle(pen, rect);
                }
                rect.Inflate(-1, -1);
                using (Pen pen = new Pen(innerBorderColor))
                {
                    g.DrawRectangle(pen, rect);
                }
            }
        }
        internal void RenderBackgroundInternalRate(Graphics g, Rectangle rect, Color baseColor, Color borderColor, Color innerBorderColor,
            float basePosition, bool drawBorder, float rate)
        {
            if (drawBorder)
            {
                rect.Width--;
                rect.Height--;
            }
            using (LinearGradientBrush brush = new LinearGradientBrush(rect, Color.Transparent, Color.Transparent, rate))
            {
                Color[] colors = new Color[4];
                colors[0] = GetColor(baseColor, 0, 35, 24, 9);
                colors[1] = GetColor(baseColor, 0, 13, 8, 3);
                colors[2] = baseColor;
                colors[3] = GetColor(baseColor, 0, 68, 69, 54);
                ColorBlend blend = new ColorBlend();
                blend.Positions = new float[] { 0.0f, basePosition, basePosition + 0.05f, 1.0f };
                blend.Colors = colors;
                brush.InterpolationColors = blend;
                g.FillRectangle(brush, rect);
            }
            if (baseColor.A > 80)
            {
                Rectangle rectTop = rect;
                if (true/*mode == LinearGradientMode.Vertical*/)
                {
                    rectTop.Height = (int)(rectTop.Height * basePosition);
                }
                else
                {
                    rectTop.Width = (int)(rect.Width * basePosition);
                }
                using (SolidBrush brushAlpha =
                    new SolidBrush(Color.FromArgb(80, 255, 255, 255)))
                {
                    g.FillRectangle(brushAlpha, rectTop);
                }
            }
            if (drawBorder)
            {
                using (Pen pen = new Pen(borderColor))
                {
                    g.DrawRectangle(pen, rect);
                }
                rect.Inflate(-1, -1);
                using (Pen pen = new Pen(innerBorderColor))
                {
                    g.DrawRectangle(pen, rect);
                }
            }
        }

        private Color GetColor(Color colorBase, int a, int r, int g, int b)
        {
            int a0 = colorBase.A;
            int r0 = colorBase.R;
            int g0 = colorBase.G;
            int b0 = colorBase.B;
            if (a + a0 > 255) { a = 255; } else { a = a + a0; }
            if (r + r0 > 255) { r = 255; } else { r = r + r0; }
            if (g + g0 > 255) { g = 255; } else { g = g + g0; }
            if (b + b0 > 255) { b = 255; } else { b = b + b0; }
            return Color.FromArgb(a, r, g, b);
        }
        private Color GetColor2(Color colorBase, int a, int r, int g, int b)
        {
            int a0 = colorBase.A;
            int r0 = colorBase.R;
            int g0 = colorBase.G;
            int b0 = colorBase.B;
            if (a + a0 > 255) { a = 255; } else { a = a + a0; }
            if (r0 - r < 0) { r = 0; } else { r = r0 - r; }
            if (g0 - g < 0) { g = 0; } else { g = g0 - g; }
            if (b0 - b < 0) { b = 0; } else { b = b0 - b; }
            return Color.FromArgb(a, r, g, b);
        }
        #endregion

        public static int LOWORD(int value)
        {
            return value & 0xFFFF;
        }

        public static int HIWORD(int value)
        {
            return value >> 16;
        }

        public void ExpandGroup(string groupName)
        {
            var node = this.AllNodes.FirstOrDefault(n => n.Name == groupName);
            if (node == null)
                return;
            BeginUpdate();
            if (!this.Nodes.Contains(node))
                this.Nodes.Insert(0, node);
            node.Expand();
            EndUpdate();
        }
    }
}