/*************************************************************************************************
  Required Notice: Copyright (C) EPPlus Software AB. 
  This software is licensed under PolyForm Noncommercial License 1.0.0 
  and may only be used for noncommercial purposes 
  https://polyformproject.org/licenses/noncommercial/1.0.0/

  A commercial license to use this software can be purchased at https://epplussoftware.com
 *************************************************************************************************
  Date               Author                       Change
 *************************************************************************************************
  27/07/2023         EPPlus Software AB         Implemented function
 *************************************************************************************************/

using OfficeOpenXml.FormulaParsing.Excel.Functions.Helpers;
using OfficeOpenXml.FormulaParsing.Excel.Functions.Metadata;
using OfficeOpenXml.FormulaParsing.FormulaExpressions;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace OfficeOpenXml.FormulaParsing.Excel.Functions.Statistical
{

    [FunctionMetadata(
    Category = ExcelFunctionCategory.Statistical,
    EPPlusVersion = "7.0",
    Description = "Calculates the F probability distribution. Takes a boolean argument that determines if PDF or CDF is used.")]
    internal class FDist : ExcelFunction
    {
        public override int ArgumentMinLength => 4;

        public override string NamespacePrefix => "_xlfn.";

        public override CompileResult Execute(IList<FunctionArgument> arguments, ParsingContext context)
        {
            var x = ArgToDecimal(arguments, 0, out ExcelErrorValue e1);
            if (e1 != null) return CompileResult.GetErrorResult(e1.Type);

            var deg_freedom1 = ArgToDecimal(arguments, 1, out ExcelErrorValue e2);
            if (e2 != null) return CompileResult.GetErrorResult(e2.Type);

            var deg_freedom2 = ArgToDecimal(arguments, 2, out ExcelErrorValue e3);
            if (e3 != null) return CompileResult.GetErrorResult(e3.Type);

            var cumulative = ArgToBool(arguments, 3);

            deg_freedom1 = Math.Floor(deg_freedom1);
            deg_freedom2 = Math.Floor(deg_freedom2);

            if (x < 0) return CreateResult(eErrorType.Num);
            if (deg_freedom1 < 1 || deg_freedom2 < 1) return CreateResult(eErrorType.Num);
            var result = FHelper.GetProbability(x, deg_freedom1, deg_freedom2, cumulative);
            return CreateResult(result, DataType.Decimal);
        }
    }
}
