SRange Contraction indicator

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

namespace cAlgo
{
    [Levels(0)]
    [Indicator(IsOverlay = false, AccessRights = AccessRights.None)]
    public class mSRangeContraction : Indicator
    {
        [Parameter("Threshold (50.0)", DefaultValue = 50.0)]
        public double inpThreshold { get; set; }
        [Parameter("Show RC (yes)", DefaultValue = true)]
        public bool inpShowRC { get; set; }
        [Parameter("Calculation Mode (current)", DefaultValue = enumCalculationMode.Current)]
        public enumCalculationMode inpCalculationMode { get; set; }

        [Output("SRange", LineColor = "Black", PlotType = PlotType.Line, Thickness = 1)]
        public IndicatorDataSeries outSRC { get; set; }
        [Output("SRange Contraction", LineColor = "Red", PlotType = PlotType.Points, Thickness = 5)]
        public IndicatorDataSeries outRC { get; set; }
        [Output("Threshold", LineColor = "Silver", PlotType = PlotType.Line, Thickness = 1)]
        public IndicatorDataSeries outThreshold { get; set; }
        
        private IndicatorDataSeries _hld, _src, _rc;
        private int lookback;
        

        protected override void Initialize()
        {
            lookback = inpCalculationMode == enumCalculationMode.Current ? 0 : 1;
            _hld = CreateDataSeries();
            _src = CreateDataSeries();
            _rc = CreateDataSeries();
        }

        public override void Calculate(int i)
        {
            _hld[i] = Bars.HighPrices[i-1-lookback] != Bars.LowPrices[i-1-lookback] ? 1 : 0;
            _src[i] = _hld[i] == 1 ? 100.0 * (Bars.HighPrices[i-lookback] - Bars.LowPrices[i-lookback]) / (Bars.HighPrices[i-1-lookback] - Bars.LowPrices[i-1-lookback]) : 0;
            _rc[i] = inpShowRC == true && _src[i] < inpThreshold ? _src[i] : double.NaN;
            
            outSRC[i] = _src[i];
            outRC[i] = _rc[i];
            outThreshold[i+100] = inpThreshold;
        }
    }
    
    public enum enumCalculationMode
    {
        Current,
        Previous
    }
}