using System;
namespace AudioStreamer.Processors
{
	public class Echo : BaseAudioProcessor
	{
		Int32 amplification;
		Int16[] delayBuffer;
		int delayPosition;

		public Echo()
		{
			delayBuffer = new short[0];
			FloatAmplification = 0.8f;
			Delay = 4096;
		}

		public Echo(int delay)
		{
			delayBuffer = new short[0];
			FloatAmplification = 0.8f;
			Delay = delay;
		}

		public Int32 Amplification { get { return this.amplification; } set { this.amplification = value; } }
		public float FloatAmplification
		{
			get { return ((float)this.amplification) / 655360f; }
			set { this.amplification = (Int32)(value * 65536.0f); }
		}

		public int Delay {
			get { return this.delayBuffer.Length; }
			set {
				if (value != delayBuffer.Length){
					lock (this){
						Array.Resize(ref delayBuffer,value);
						delayPosition %= value;
					}
				}
			}
		}

		protected override void process(ref short[] samples)
		{
			lock (this){

				for (int n = 0; n < samples.Length;n++){
					delayBuffer[delayPosition] = (Int16)(((((Int32)delayBuffer[delayPosition]) * this.amplification) >> 16) + samples[n]);
					samples[n] = delayBuffer[delayPosition];
					delayPosition++;
					delayPosition %= delayBuffer.Length;
				}

			}
		}

	}
}