using System.Drawing.Drawing2D;

namespace ClinicBackupSync;

sealed class UploadProgressBar : Control
{
    readonly System.Windows.Forms.Timer _timer;
    readonly Font _percentFont;
    string _fileName = "";
    float _target;
    float _shown;
    float _shimmer;
    float _spin;
    bool _active;

    public UploadProgressBar()
    {
        SetStyle(ControlStyles.AllPaintingInWmPaint | ControlStyles.OptimizedDoubleBuffer | ControlStyles.UserPaint | ControlStyles.ResizeRedraw, true);
        Height = 58;
        Font = new Font("Segoe UI", 9.5f);
        _percentFont = new Font(Font, FontStyle.Bold);
        BackColor = Color.FromArgb(231, 238, 242);
        _timer = new System.Windows.Forms.Timer { Interval = 32 };
        _timer.Tick += (_, _) => Animate();
    }

    public void ShowUpload(string fileName)
    {
        if (!_active || !string.Equals(_fileName, fileName, StringComparison.OrdinalIgnoreCase))
        {
            _fileName = fileName;
            _target = 0;
            _shown = 0;
            _shimmer = 0;
        }

        _active = true;
        Visible = true;
        _timer.Start();
        Invalidate();
    }

    public void SetProgress(string fileName, int percent)
    {
        _fileName = fileName;
        _target = Math.Clamp(percent, 0, 100);
        _active = true;
        Visible = true;
        if (!_timer.Enabled)
        {
            _timer.Start();
        }

        Invalidate();
    }

    public void HideIdle()
    {
        _active = false;
        _target = 0;
        _shown = 0;
        _timer.Stop();
        Visible = false;
    }

    protected override void Dispose(bool disposing)
    {
        if (disposing)
        {
            _timer.Dispose();
            _percentFont.Dispose();
        }

        base.Dispose(disposing);
    }

    void Animate()
    {
        _shown += (_target - _shown) * 0.22f;
        if (Math.Abs(_target - _shown) < 0.15f)
        {
            _shown = _target;
        }

        _shimmer = (_shimmer + 0.018f) % 1f;
        _spin = (_spin + 9f) % 360f;
        Invalidate();
    }

    protected override void OnPaint(PaintEventArgs e)
    {
        var graphics = e.Graphics;
        graphics.SmoothingMode = SmoothingMode.AntiAlias;
        graphics.Clear(BackColor);
        if (!_active && !Visible)
        {
            return;
        }

        var percent = (int)Math.Round(_target);
        var spinner = new Rectangle(18, 10, 16, 16);
        using (var pen = new Pen(Color.FromArgb(40, 12, 110, 105), 2.2f))
        {
            graphics.DrawEllipse(pen, spinner);
        }

        using (var pen = new Pen(Color.FromArgb(12, 110, 105), 2.2f))
        {
            pen.StartCap = LineCap.Round;
            pen.EndCap = LineCap.Round;
            graphics.DrawArc(pen, spinner, _spin, 110);
        }

        var name = string.IsNullOrWhiteSpace(_fileName) ? "Uploading" : _fileName;
        var percentText = $"{percent}%";
        var percentSize = TextRenderer.MeasureText(percentText, _percentFont);
        var nameBounds = new Rectangle(40, 8, Math.Max(40, Width - 56 - percentSize.Width), 20);
        TextRenderer.DrawText(graphics, name, Font, nameBounds, Color.FromArgb(16, 40, 58), TextFormatFlags.Left | TextFormatFlags.VerticalCenter | TextFormatFlags.EndEllipsis | TextFormatFlags.NoPrefix);
        TextRenderer.DrawText(graphics, percentText, _percentFont, new Rectangle(Width - percentSize.Width - 16, 8, percentSize.Width, 20), Color.FromArgb(12, 110, 105), TextFormatFlags.Right | TextFormatFlags.VerticalCenter);

        var track = new Rectangle(18, 34, Math.Max(8, Width - 36), 10);
        FillRound(graphics, track, Color.FromArgb(214, 224, 228));

        if (_shown < 1f)
        {
            var chunk = Math.Max(36, track.Width / 5);
            var travel = track.Width + chunk;
            var x = track.X + (int)(_shimmer * travel) - chunk;
            using (var clip = Round(track))
            {
                graphics.SetClip(clip);
                FillRound(graphics, new Rectangle(x, track.Y, chunk, track.Height), Color.FromArgb(12, 110, 105));
                graphics.ResetClip();
            }
            return;
        }

        var fillWidth = Math.Max(10, (int)(track.Width * (_shown / 100f)));
        var fill = new Rectangle(track.X, track.Y, Math.Min(track.Width, fillWidth), track.Height);
        FillRound(graphics, fill, Color.FromArgb(12, 110, 105));

        var shineWidth = Math.Max(24, fill.Width / 3);
        var shineX = fill.X + (int)((_shimmer * (fill.Width + shineWidth)) - shineWidth);
        using (var clip = Round(fill))
        {
            graphics.SetClip(clip);
            using var brush = new LinearGradientBrush(
                new Rectangle(shineX, fill.Y, shineWidth, fill.Height),
                Color.FromArgb(0, 255, 255, 255),
                Color.FromArgb(170, 255, 255, 255),
                LinearGradientMode.Horizontal);
            brush.SetBlendTriangularShape(0.5f);
            graphics.FillRectangle(brush, shineX, fill.Y, shineWidth, fill.Height);
            graphics.ResetClip();
        }
    }

    static void FillRound(Graphics graphics, Rectangle bounds, Color color)
    {
        using var path = Round(bounds);
        using var brush = new SolidBrush(color);
        graphics.FillPath(brush, path);
    }

    static GraphicsPath Round(Rectangle bounds)
    {
        var radius = bounds.Height;
        var path = new GraphicsPath();
        if (bounds.Width <= radius)
        {
            path.AddEllipse(bounds);
            return path;
        }

        path.AddArc(bounds.X, bounds.Y, radius, radius, 90, 180);
        path.AddArc(bounds.Right - radius, bounds.Y, radius, radius, 270, 180);
        path.CloseFigure();
        return path;
    }
}