Live Roulette v1 (#59)

* Enabling/disabling gamba games with dynamic settting lookup.

* Its roulette baby

KfChatDotNetBot/Commands/Kasino/Roulette/RouletteanImationGenerator.cs

@@ -0,0 +1,137 @@
+using SixLabors.Fonts;
+using SixLabors.ImageSharp;
+using SixLabors.ImageSharp.Drawing;
+using SixLabors.ImageSharp.Drawing.Processing;
+using SixLabors.ImageSharp.Formats.Webp;
+using SixLabors.ImageSharp.PixelFormats;
+using SixLabors.ImageSharp.Processing;
+
+namespace KfChatDotNetBot.Commands.Kasino.Roulette;
+
+public static class RouletteAnimationGenerator
+{
+    // European Wheel Sequence
+    private static readonly int[] WheelNumbers = {
+        0, 32, 15, 19, 4, 21, 2, 25, 17, 34, 6, 27, 13, 36, 11, 30, 8, 23, 10, 5, 24, 16, 33, 1, 20, 14, 31, 9, 22, 18, 29, 7, 28, 12, 35, 3, 26
+    };
+
+    /// <summary>
+    /// Generates an animated roulette wheel that lands on the specified winning number
+    /// </summary>
+    /// <param name="winningNumber">The number (0-36) that the ball should land on</param>
+    /// <returns>A tuple containing the animation duration in seconds and the WebP animation bytes</returns>
+    public static (int durationSeconds, byte[] animationBytes) GenerateAnimation(int winningNumber)
+    {
+        if (winningNumber < 0 || winningNumber > 36)
+        {
+            throw new ArgumentOutOfRangeException(nameof(winningNumber), "Winning number must be between 0 and 36");
+        }
+
+        using var board = DrawWheelBase();
+        int fps = 20;
+        int duration = Random.Shared.Next(6, 9);
+        int totalFrames = fps * duration;
+        using var animation = new Image<Rgba32>(500, 500);
+
+        // Find the index of the winning number in the wheel sequence
+        int winningIndex = Array.IndexOf(WheelNumbers, winningNumber);
+        if (winningIndex == -1)
+        {
+            throw new InvalidOperationException($"Winning number {winningNumber} not found in wheel sequence");
+        }
+
+        // Set the "Journey"
+        float endWheelRotation = 720f + Random.Shared.Next(0, 360);
+        float sliceAngle = 360f / 37f;
+        
+        // The pocket index 'i' is located at (i * sliceAngle) degrees relative to wheel zero.
+        // Our '0' pocket was drawn at -90 degrees.
+        float pocketOffsetOnWheel = (winningIndex * sliceAngle) - 90;
+        
+        // This is where the ball MUST be at the end of the video
+        float finalBallAngle = endWheelRotation + pocketOffsetOnWheel;
+
+        // Render frames
+        for (int i = 0; i < totalFrames; i++)
+        {
+            float progress = (float)i / totalFrames;
+            float ease = 1f - MathF.Pow(1f - progress, 3); // Smooth stop
+
+            // Wheel rotates Clockwise (Adding degrees)
+            float currentWheelAngle = endWheelRotation * ease;
+            
+            // Ball rotates Counter-Clockwise (Starting high and subtracting)
+            // We start with 5 extra laps (1800 degrees) and "go back" to the final angle
+            float startBallAngle = finalBallAngle + 1800f;
+            float currentBallAngle = startBallAngle - ((startBallAngle - finalBallAngle) * ease);
+
+            var frame = new Image<Rgba32>(500, 500);
+            frame.Mutate(ctx => {
+                // Draw Wheel
+                using var rotatedBoard = board.Clone(b => b.Rotate(currentWheelAngle));
+                int ox = 250 - (rotatedBoard.Width / 2);
+                int oy = 250 - (rotatedBoard.Height / 2);
+                ctx.DrawImage(rotatedBoard, new Point(ox, oy), 1f);
+
+                // Ball Radius (Physics)
+                float dropT = MathF.Max(0, (progress - 0.7f) / 0.3f);
+                float radius = 230 - (45 * MathF.Pow(dropT, 2));
+                
+                float rads = currentBallAngle * MathF.PI / 180;
+                float bx = 250 + (radius * MathF.Cos(rads));
+                float by = 250 + (radius * MathF.Sin(rads));
+                
+                ctx.Fill(Color.White, new EllipsePolygon(bx, by, 14));
+            });
+
+            frame.Frames.RootFrame.Metadata.GetWebpMetadata().FrameDelay = (uint)(1000 / fps);
+            animation.Frames.AddFrame(frame.Frames.RootFrame);
+            frame.Dispose();
+        }
+
+        animation.Frames.RemoveFrame(0);
+        using var ms = new MemoryStream();
+        animation.SaveAsWebp(ms, new WebpEncoder { FileFormat = WebpFileFormatType.Lossy, Quality = 50 });
+        
+        return (duration, ms.ToArray());
+    }
+
+    private static Image<Rgba32> DrawWheelBase()
+    {
+        var img = new Image<Rgba32>(500, 500);
+        float centerX = 250, centerY = 250, outerRadius = 245, innerRadius = 170, step = 360f / 37f;
+        
+        img.Mutate(ctx => {
+            for (int i = 0; i < 37; i++) {
+                float startAngle = i * step - (step / 2) - 90;
+                var color = WheelNumbers[i] == 0 ? Color.Green : (i % 2 == 0 ? Color.DarkRed : Color.Black);
+                var path = new PathBuilder().AddArc(centerX, centerY, outerRadius, outerRadius, 0, startAngle, step)
+                    .AddArc(centerX, centerY, innerRadius, innerRadius, 0, startAngle + step, -step).Build();
+                ctx.Fill(color, path);
+                ctx.Draw(Color.Gold, 1, path);
+                
+                string text = WheelNumbers[i].ToString();
+                float textAngle = (startAngle + (step / 2)) * MathF.PI / 180;
+                float tx = centerX + ((outerRadius + innerRadius) / 2) * MathF.Cos(textAngle);
+                float ty = centerY + ((outerRadius + innerRadius) / 2) * MathF.Sin(textAngle);
+                
+                try {
+                    var font = SystemFonts.CreateFont("Arial", 14, FontStyle.Bold);
+                    ctx.DrawText(
+                        new DrawingOptions { 
+                            Transform = Matrix3x2Extensions.CreateRotationDegrees(startAngle + (step / 2) + 90, new PointF(tx, ty)) 
+                        }, 
+                        text, 
+                        font, 
+                        Color.White, 
+                        new PointF(tx - 6, ty - 9));
+                } catch { 
+                    // Font loading failed, skip text rendering
+                }
+            }
+            ctx.Fill(Color.DarkSlateGray, new EllipsePolygon(centerX, centerY, innerRadius - 5));
+        });
+        
+        return img;
+    }
+}