using System;
using System.Collections.Generic;
 
namespace Microsoft.Maui.Devices.Sensors
{
	class LowPassFilter
	{
		const int length = 10;
 
		readonly Queue<float> history = new Queue<float>(length);
		float sin;
		float cos;
 
		internal void Add(float radians)
		{
			sin += MathF.Sin(radians);
 
			cos += MathF.Cos(radians);
 
			history.Enqueue(radians);
 
			if (history.Count > length)
			{
				var old = history.Dequeue();
 
				sin -= MathF.Sin(old);
 
				cos -= MathF.Cos(old);
			}
		}
 
		internal float Average()
		{
			var size = history.Count;
 
			return MathF.Atan2(sin / size, cos / size);
		}
	}
}