using System.Drawing;
using System.Drawing.Drawing2D;
using System.Windows.Forms;
using System.ComponentModel;

namespace ControlServer
{
    public class RoundedPanel : Panel
    {
        [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
        public int CornerRadius { get; set; } = 30;

        public RoundedPanel()
        {
            this.DoubleBuffered = true;
            // 컨트롤의 배경색이 바뀔 때 다시 그리도록 설정
            this.SetStyle(ControlStyles.AllPaintingInWmPaint |
                          ControlStyles.OptimizedDoubleBuffer |
                          ControlStyles.ResizeRedraw |
                          ControlStyles.UserPaint, true);
        }

        protected override void OnPaint(PaintEventArgs e)
        {
            e.Graphics.SmoothingMode = SmoothingMode.AntiAlias;

            // 배경을 투명하게 처리하고 둥근 영역만 남김
            using (GraphicsPath path = new GraphicsPath())
            {
                path.AddArc(0, 0, CornerRadius, CornerRadius, 180, 90);
                path.AddArc(Width - CornerRadius - 1, 0, CornerRadius, CornerRadius, 270, 90);
                path.AddArc(Width - CornerRadius - 1, Height - CornerRadius - 1, CornerRadius, CornerRadius, 0, 90);
                path.AddArc(0, Height - CornerRadius - 1, CornerRadius, CornerRadius, 90, 90);
                path.CloseAllFigures();

                // 영역(Region)을 설정하여 모서리 바깥쪽을 클릭 방지 및 투명 처리
                this.Region = new Region(path);

                // 배경 채우기
                using (SolidBrush brush = new SolidBrush(this.BackColor))
                {
                    e.Graphics.FillPath(brush, path);
                }
            }

            base.OnPaint(e);
        }
    }
}