using CoreAnimation;
using CoreGraphics;
using Microsoft.Maui.Graphics;
using ObjCRuntime;
using UIKit;
 
namespace Microsoft.Maui.Platform
{
	internal static class ShadowExtensions
	{
		public static void SetShadow(this UIView platformView, IShadow? shadow)
		{
			if (shadow == null || shadow.Paint == null)
				return;
 
			var layer = platformView.Layer;
			layer?.SetShadow(shadow);
		}
 
		public static void SetShadow(this CALayer layer, IShadow? shadow)
		{
			if (shadow?.Paint?.ToColor() is not { } paintColor)
				return;
 
			var radius = shadow.Radius;
			var opacity = shadow.Opacity;
			var color = paintColor.ToPlatform();
 
			var offset = new CGSize(shadow.Offset.X, shadow.Offset.Y);
 
			layer.ShadowColor = color.CGColor;
			layer.ShadowOpacity = opacity;
			layer.ShadowRadius = radius / 2;
			layer.ShadowOffset = offset;
 
			layer.SetNeedsDisplay();
		}
 
		public static void ClearShadow(this UIView platformView)
		{
			var layer = platformView.Layer;
			layer?.ClearShadow();
		}
 
		public static void ClearShadow(this CALayer layer)
		{
			layer.ShadowColor = new CGColor(0, 0, 0, 0);
			layer.ShadowRadius = 0;
			layer.ShadowOffset = new CGSize();
			layer.ShadowOpacity = 0;
		}
	}
}