using System;



namespace CommonSupport

{

	public class SimpleMovingAverage : IMovingAverage

	{

		CircularList<float> samples;

		protected float total;



		/// <summary>

		/// Get the average for the current number of samples.

		/// </summary>

		public float Average

		{

			get

			{

				if (samples.Count == 0)

				{

					throw new ApplicationException("Number of samples is 0.");

				}



				return total / samples.Count;

			}

		}



		/// <summary>

		/// Constructor, initializing the sample size to the specified number.

		/// </summary>

		public SimpleMovingAverage(int numSamples)

		{

			if (numSamples <= 0)

			{

				throw new ArgumentOutOfRangeException("numSamples can't be negative or 0.");

			}



			samples = new CircularList<float>(numSamples);

			total = 0;

		}



		/// <summary>

		/// Adds a sample to the sample collection.

		/// </summary>

		public void AddSample(float val)

		{

			if (samples.Count == samples.Length)

			{

				total -= samples.Value;

			}



			samples.Value = val;

			total += val;

			samples.Next();

		}



		/// <summary>

		/// Clears all samples to 0.

		/// </summary>

		public void ClearSamples()

		{

			total = 0;

			samples.Clear();

		}



		/// <summary>

		/// Initializes all samples to the specified value.

		/// </summary>

		public void InitializeSamples(float v)

		{

			samples.SetAll(v);

			total = v * samples.Length;

		}

	}

}