using System;
using QuanTAlib;
using Skender.Stock.Indicators;
using Xunit;

namespace Validations;
public class Skender
{
  private readonly GBM_Feed bars;
  private readonly Random rnd = new();
  private readonly int period, digits, skip;
  private readonly IEnumerable<Quote> quotes;
	

  public Skender()
  {
    bars = new(Bars: 10000, Volatility: 0.5, Drift: 0.0, Precision: 2);
    period = rnd.Next(30) + 5;
    digits = 2; //minimizing rounding errors in type conversions
    skip = 300;

    quotes = bars.Select(q => new Quote
    {
      Date = q.t,
      Open = (decimal)q.o,
      High = (decimal)q.h,
      Low = (decimal)q.l,
      Close = (decimal)q.c,
      Volume = (decimal)q.v
    });
  }

  [Fact]
  public void ADL()
  {
    // TODO: check precision of ADL()
    ADL_Series QL = new(bars, false);
    var SK = quotes.GetAdl().Select(i => i.Adl);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round(SK.ElementAt(i - 1)!, digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void ALMA()
  {
    ALMA_Series QL = new(bars.Close, period, useNaN: false);
    var SK = quotes.GetAlma(period).Select(i => i.Alma.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round((double)SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void ATR()
  {
    ATR_Series QL = new(bars, period, false);
    var SK = quotes.GetAtr(period).Select(i => i.Atr.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round((double)SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void ATRP()
  {
    ATRP_Series QL = new(bars, period, false);
    var SK = quotes.GetAtr(period).Select(i => i.Atrp.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round((double)SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void BBANDS()
  {
    BBANDS_Series QL = new(bars.Close, period, 2.0, useNaN: false);
    var SK = quotes.GetBollingerBands(period, 2.0);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL.Mid[i - 1].v, digits: digits);
      double SK_item = Math.Round((double)SK.ElementAt(i - 1).Sma!.Value, digits: digits);
      Assert.Equal(SK_item!, QL_item);
      QL_item = Math.Round(QL.Upper[i - 1].v, digits: digits);
      SK_item = Math.Round((double)SK.ElementAt(i - 1).UpperBand!.Value, digits: digits);
      Assert.Equal(SK_item!, QL_item);
      QL_item = Math.Round(QL.Lower[i - 1].v, digits: digits);
      SK_item = Math.Round((double)SK.ElementAt(i - 1).LowerBand!.Value, digits: digits);
      Assert.Equal(SK_item!, QL_item);
      QL_item = Math.Round(QL.Bandwidth[i - 1].v, digits: digits);
      SK_item = Math.Round((double)SK.ElementAt(i - 1).Width!.Value, digits: digits);
      Assert.Equal(SK_item!, QL_item);
      QL_item = Math.Round(QL.PercentB[i - 1].v, digits: digits);
      SK_item = Math.Round((double)SK.ElementAt(i - 1).PercentB!.Value, digits: digits);
      Assert.Equal(SK_item!, QL_item);
      QL_item = Math.Round(QL.Zscore[i - 1].v, digits: digits);
      SK_item = Math.Round((double)SK.ElementAt(i - 1).ZScore!.Value, digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void CCI()
  {
    CCI_Series QL = new(bars, period, false);
    var SK = quotes.GetCci(period).Select(i => i.Cci.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round((double)SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void CORR()
  {
    CORR_Series QL = new(bars.High, bars.Low, period, false);
    var SK = quotes.Use(CandlePart.High).GetCorrelation(quotes.Use(CandlePart.Low), period).Select(i => i.Correlation.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round((double)SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void COVAR()
  {
    COVAR_Series QL = new(bars.High, bars.Low, period, false);
    var SK = quotes.Use(CandlePart.High).GetCorrelation(quotes.Use(CandlePart.Low), period).Select(i => i.Covariance.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round((double)SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void DEMA()
  {
    DEMA_Series QL = new(bars.Close, period, false);
    var SK = quotes.GetDema(period).Select(i => i.Dema.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round((double)SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void EMA()
  {
    EMA_Series QL = new(bars.Close, period, false);
    var SK = quotes.GetEma(period).Select(i => i.Ema.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round((double)SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
	/*
  [Fact]
  public void HL2()
  {
    TSeries QL = bars.HL2;
    var SK = quotes.GetBaseQuote(CandlePart.HL2).Select(i => i.Value);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round((double)SK.ElementAt(i - 1)!, digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void HLC3()
  {
    TSeries QL = bars.HLC3;
    var SK = quotes.GetBaseQuote(CandlePart.HLC3).Select(i => i.Value);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round((double)SK.ElementAt(i - 1)!, digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
	*/
  [Fact]
  public void HMA()
  {
    HMA_Series QL = new(bars.Close, period, useNaN: false);
    var SK = quotes.GetHma(period).Select(i => i.Hma.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round(SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void KAMA()
  {
    // TODO: check precision of KAMA()
    KAMA_Series QL = new(bars.Close, period, useNaN: false);
    var SK = quotes.GetKama(period).Select(i => i.Kama.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round(SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void LINREG()
  {
    LINREG_Series QL = new(bars.Close, period, useNaN: false);
    var SK = quotes.GetSlope(period);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round((double)SK.ElementAt(i - 1).Slope!, digits: digits);
      Assert.Equal(SK_item!, QL_item);
      QL_item = Math.Round(QL.Intercept[i - 1].v, digits: digits);
      SK_item = Math.Round((double)SK.ElementAt(i - 1).Intercept!, digits: digits);
      Assert.Equal(SK_item!, QL_item);
      QL_item = Math.Round(QL.RSquared[i - 1].v, digits: digits);
      SK_item = Math.Round((double)SK.ElementAt(i - 1).RSquared!, digits: digits);
      Assert.Equal(SK_item!, QL_item);
      QL_item = Math.Round(QL.StdDev[i - 1].v, digits: digits);
      SK_item = Math.Round((double)SK.ElementAt(i - 1).StdDev!, digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void MACD()
  {
    MACD_Series QL = new(bars.Close, 26, 12, 9, useNaN: false);
    var SK = quotes.GetMacd(12, 26, 9);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round(SK.ElementAt(i - 1).Macd.Null2NaN()!, digits: digits);
      Assert.Equal(SK_item!, QL_item);
      QL_item = Math.Round(QL.Signal[i - 1].v, digits: digits);
      SK_item = Math.Round(SK.ElementAt(i - 1).Signal.Null2NaN()!, digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void MAD()
  {
    MAD_Series QL = new(bars.Close, period, false);
    var SK = quotes.GetSmaAnalysis(period).Select(i => i.Mad.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round(SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void MAMA()
  {
    MAMA_Series QL = new(bars.HL2, fastlimit: 0.5, slowlimit: 0.05);
    var SK = quotes.GetMama(fastLimit: 0.5, slowLimit: 0.05);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round(SK.ElementAt(i - 1).Mama.Null2NaN()!, digits: digits);
      Assert.Equal(SK_item!, QL_item);
      QL_item = Math.Round(QL.Fama[i - 1].v, digits: digits);
      SK_item = Math.Round(SK.ElementAt(i - 1).Fama.Null2NaN()!, digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void MAPE()
  {
    MAPE_Series QL = new(bars.Close, period, false);
    var SK = quotes.GetSmaAnalysis(period).Select(i => i.Mape.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round(SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void MSE()
  {
    MSE_Series QL = new(bars.Close, period, false);
    var SK = quotes.GetSmaAnalysis(period).Select(i => i.Mse.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round(SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void OBV()
  {
    OBV_Series QL = new(bars, period, false);
    var SK = quotes.GetObv(period).Select(i => i.Obv!);
    // adding volume[0] to OBV to pass the test and keep compatibility with TA-LIB
        for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL.Last().v, digits: digits);
      double SK_item = Math.Round(SK.Last()! + (double)quotes.First().Volume!, digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
	/*
  [Fact]
  public void OC2()
  {
    TSeries QL = bars.OC2;
    var SK = quotes.GetBaseQuote(CandlePart.OC2).Select(i => i.Value);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round((double)SK.ElementAt(i - 1)!, digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
	[Fact]
  public void OHL3()
  {
    TSeries QL = bars.OHL3;
    var SK = quotes.GetBaseQuote(CandlePart.OHL3).Select(i => i.Value);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round((double)SK.ElementAt(i - 1)!, digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void OHLC4()
  {
    TSeries QL = bars.OHLC4;
    var SK = quotes.GetBaseQuote(CandlePart.OHLC4).Select(i => i.Value);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round((double)SK.ElementAt(i - 1)!, digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
	*/
	[Fact]
  public void RSI()
  {
    RSI_Series QL = new(bars.Close, period, useNaN: false);
    var SK = quotes.GetRsi(period).Select(i => i.Rsi.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round(SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void SDEV()
  {
    SDEV_Series QL = new(bars.Close, period, useNaN: false);
    var SK = quotes.GetStdDev(period).Select(i => i.StdDev.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round(SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void SMA()
  {
    SMA_Series QL = new(bars.Close, period, false);
    var SK = quotes.GetSma(period).Select(i => i.Sma.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round(SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void SMMA()
  {
    SMMA_Series QL = new(bars.Close, period, useNaN: false);
    var SK = quotes.GetSmma(period).Select(i => i.Smma.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round(SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void T3()
  {
    T3_Series QL = new(source: bars.Close, period: period, vfactor: 0.7, false);
    var SK = quotes.GetT3(lookbackPeriods: period, volumeFactor: 0.7).Select(i => i.T3.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round(SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void TEMA()
  {
    TEMA_Series QL = new(bars.Close, period, false);
    var SK = quotes.GetTema(period).Select(i => i.Tema.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round(SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void TR()
  {
    TR_Series QL = new(bars, useNaN: false);
    var SK = quotes.GetTr().Select(i => i.Tr.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round(SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void WMA()
  {
    WMA_Series QL = new(bars.Close, period, false);
    var SK = quotes.GetWma(period).Select(i => i.Wma.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round(SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }
  [Fact]
  public void ZSCORE()
  {
    ZSCORE_Series QL = new(bars.Close, period, useNaN: false);
    var SK = quotes.GetStdDev(period).Select(i => i.ZScore.Null2NaN()!);
    for (int i = QL.Length; i > skip; i--)
    {
      double QL_item = Math.Round(QL[i - 1].v, digits: digits);
      double SK_item = Math.Round(SK.ElementAt(i - 1), digits: digits);
      Assert.Equal(SK_item!, QL_item);
    }
  }

}