using System;

 using System.Collections.Generic;

 using CSCore.DSP;

 namespace Visualization

 {

     /// <summary>

     ///     BasicSpectrumProvider

     /// </summary>

     public class BasicSpectrumProvider : FftProvider, ISpectrumProvider

     {

         private readonly int _sampleRate;

         private readonly List<object> _contexts = new List<object>();

         public BasicSpectrumProvider(int channels, int sampleRate, FftSize fftSize)

             : base(channels, fftSize)

         {

             if (sampleRate <= 0)

                 throw new ArgumentOutOfRangeException("sampleRate");

             _sampleRate = sampleRate;

         }

         public int GetFftBandIndex(float frequency)

         {

             int fftSize = (int)FftSize;

             double f = _sampleRate / 2.0;

             // ReSharper disable once PossibleLossOfFraction

             return (int)((frequency / f) * (fftSize / 2));

         }

         public bool GetFftData(float[] fftResultBuffer, object context)

         {

             if (_contexts.Contains(context))

                 return false;

             _contexts.Add(context);

             GetFftData(fftResultBuffer);

             return true;

         }

         public override void Add(float[] samples, int count)

         {

             base.Add(samples, count);

             if (count > 0)

                 _contexts.Clear();

         }

         public override void Add(float left, float right)

         {

             base.Add(left, right);

             _contexts.Clear();

         }

     }

 }