Ehlers Detrending Filter indicator

using System;
using cAlgo.API;
using cAlgo.API.Collections;
using cAlgo.API.Indicators;
using cAlgo.API.Internals;

namespace cAlgo
{
    [Levels(0)]
    [Indicator(IsOverlay = false, AccessRights = AccessRights.None)]
    public class mEhlersDetrendingFilter : Indicator
    {
        [Parameter("Data Source (hlcc4)", DefaultValue = enumPriceTypes.hlcc4)]
        public enumPriceTypes inpPriceType { get; set; }
        [Parameter("Period (10)", DefaultValue = 10)]
        public int inpPeriod { get; set; }

        [Output("Ehlers Detrending Filter", LineColor = "Black", PlotType = PlotType.DiscontinuousLine, Thickness = 1)]
        public IndicatorDataSeries outEDF { get; set; }
        
        private IndicatorDataSeries _price, _edf, _filtq;
        private double _cosine, _filt, _coef;
        

        protected override void Initialize()
        {
            _price = CreateDataSeries();
            _edf = CreateDataSeries();
            _filtq = CreateDataSeries();
        }

        public override void Calculate(int i)
        {
            switch (inpPriceType)
            {
                case enumPriceTypes.Open:
                    _price[i] = Bars.OpenPrices[i];
                    break;
                case enumPriceTypes.Close:
                    _price[i] = Bars.ClosePrices[i];
                     break;
                case enumPriceTypes.High:
                     _price[i] = Bars.HighPrices[i];
                     break;
                case enumPriceTypes.Low:
                     _price[i] = Bars.LowPrices[i];
                     break;
                case enumPriceTypes.Median:
                     _price[i] = Bars.MedianPrices[i];
                     break;
                case enumPriceTypes.Typical:
                    _price[i] = Bars.TypicalPrices[i];
                    break;
                case enumPriceTypes.Weighted:
                    _price[i] = Bars.WeightedPrices[i];
                    break;
                case enumPriceTypes.hl2:
                    _price[i] = (Bars.HighPrices[i] + Bars.LowPrices[i]) / 2;
                    break;
                case enumPriceTypes.hlc3:
                    _price[i] = (Bars.HighPrices[i] + Bars.LowPrices[i] + Bars.ClosePrices[i]) / 3;
                    break;
                case enumPriceTypes.hlcc4:
                    _price[i] = (Bars.HighPrices[i] + Bars.LowPrices[i] + Bars.ClosePrices[i] + Bars.ClosePrices[i]) / 4;
                    break;
                case enumPriceTypes.ohlc4:
                    _price[i] = (Bars.OpenPrices[i] + Bars.HighPrices[i] + Bars.LowPrices[i] + Bars.ClosePrices[i]) / 4;
                    break;
                case enumPriceTypes.FIR:
                    _price[i] = i>4 ? (Bars.ClosePrices[i] + 2.0 * Bars.ClosePrices[i-1] + 2.0 * Bars.ClosePrices[i-2] + Bars.ClosePrices[i-3]) / 6.0 : Bars.ClosePrices[i];
                    break;
                default:
                    _price[i] = Bars.ClosePrices[i];
                     break;
            }

            _edf[i] = i>1 ? (0.95 * _price[i]) - (0.95 * _price[i-1]) + (0.95 * _edf[i-1]) : (0.95 * _price[i]);
            _filt = 0;
            _coef = 0;
            for (int j=1; j<=inpPeriod; j++)
            {
                _cosine = 1 - Math.Cos(2 * Math.PI * j / (inpPeriod + 1));
                _filt += _filt + (_cosine * _edf[i-j-1]);
                _coef += _coef + _cosine;
            } 
            _filtq[i] = _coef != 0 ? _filt / _coef : 0;
            
            outEDF[i] = _filtq[i];
        }
    }
    
    public enum enumPriceTypes
    {
        Open,
        Close,
        High,
        Low,
        Median,
        Typical,
        Weighted,
        hl2,
        hlc3,
        hlcc4,
        ohlc4,
        FIR
    }
}