using System;
using System.Drawing;
using System.Drawing.Drawing2D;

namespace StarfaceOutlookSync.UI
{
    /// <summary>
    /// Generiert das App-Icon programmatisch (Kontakt-Symbol mit Sync-Pfeilen).
    /// Kein externes ICO-File noetig.
    /// </summary>
    public static class AppIcon
    {
        private static Icon _icon;

        public static Icon GetIcon()
        {
            if (_icon != null) return _icon;
            _icon = CreateIcon(32);
            return _icon;
        }

        public static Icon GetSmallIcon()
        {
            return CreateIcon(16);
        }

        private static Icon CreateIcon(int size)
        {
            using (var bmp = new Bitmap(size, size))
            using (var g = Graphics.FromImage(bmp))
            {
                g.SmoothingMode = SmoothingMode.AntiAlias;
                g.Clear(Color.Transparent);

                if (size >= 32)
                    DrawIcon32(g);
                else
                    DrawIcon16(g);

                return Icon.FromHandle(bmp.GetHicon());
            }
        }

        private static void DrawIcon32(Graphics g)
        {
            // Hintergrund: abgerundetes Quadrat
            using (var bgBrush = new SolidBrush(Color.FromArgb(0, 120, 212)))
            {
                FillRoundedRect(g, bgBrush, 0, 0, 31, 31, 6);
            }

            // Person (Kopf)
            using (var whiteBrush = new SolidBrush(Color.White))
            {
                g.FillEllipse(whiteBrush, 11, 4, 10, 10);
                // Person (Koerper)
                g.FillPie(whiteBrush, 6, 14, 20, 18, 180, 180);
            }

            // Sync-Pfeile unten rechts
            using (var arrowPen = new Pen(Color.FromArgb(120, 255, 120), 2f))
            {
                arrowPen.StartCap = LineCap.Round;
                arrowPen.EndCap = LineCap.ArrowAnchor;
                // Pfeil rechts
                g.DrawArc(arrowPen, 20, 22, 10, 8, 200, 140);
                arrowPen.Color = Color.FromArgb(255, 200, 80);
                // Pfeil links
                g.DrawArc(arrowPen, 20, 22, 10, 8, 20, 140);
            }
        }

        private static void DrawIcon16(Graphics g)
        {
            // Hintergrund
            using (var bgBrush = new SolidBrush(Color.FromArgb(0, 120, 212)))
            {
                FillRoundedRect(g, bgBrush, 0, 0, 15, 15, 3);
            }

            // Person (vereinfacht)
            using (var whiteBrush = new SolidBrush(Color.White))
            {
                g.FillEllipse(whiteBrush, 4, 1, 7, 7);
                g.FillPie(whiteBrush, 2, 8, 12, 10, 180, 180);
            }

            // Kleiner Sync-Indikator
            using (var dotBrush = new SolidBrush(Color.FromArgb(120, 255, 120)))
            {
                g.FillEllipse(dotBrush, 11, 11, 4, 4);
            }
        }

        private static void FillRoundedRect(Graphics g, Brush brush, int x, int y, int w, int h, int r)
        {
            using (var path = new GraphicsPath())
            {
                path.AddArc(x, y, r * 2, r * 2, 180, 90);
                path.AddArc(x + w - r * 2, y, r * 2, r * 2, 270, 90);
                path.AddArc(x + w - r * 2, y + h - r * 2, r * 2, r * 2, 0, 90);
                path.AddArc(x, y + h - r * 2, r * 2, r * 2, 90, 90);
                path.CloseFigure();
                g.FillPath(brush, path);
            }
        }
    }
}