using System;
using System.Collections.Generic;
using System.Windows.Media;
using System.Windows.Media.Effects;

namespace Dominion.NET_WPF.Caching
{
	public static class DropShadowRepository
	{
		private static readonly Dictionary<int, DropShadowEffect> DSECache = new Dictionary<int, DropShadowEffect>();

		public static DropShadowEffect GetDSE(int blurRadius, Color color, double opacity)
		{
			return GetDSE(blurRadius, color, opacity, true);
		}

		public static DropShadowEffect GetDSE(int blurRadius, Color color, double opacity, bool isFrozen)
		{
			var hashKey = 3 * blurRadius.GetHashCode() + 5 * color.GetHashCode() + 7 * opacity.GetHashCode();

			if (!isFrozen || !DSECache.ContainsKey(hashKey))
			{
			    var dse = new DropShadowEffect
			    {
			        BlurRadius = blurRadius,
			        Color = color,
			        Opacity = opacity,
			        ShadowDepth = 0,
			        Direction = 0
			    };
			    if (!isFrozen)
					return dse;

				DSECache[hashKey] = dse;
			}

			if (DSECache[hashKey].CanFreeze)
				DSECache[hashKey].Freeze();
			return DSECache[hashKey];
		}
	}
}