﻿using System.Collections.Generic;
using System.Globalization;
using System.Linq;

namespace AppsheetEpplus;

public class Fixed : ExcelFunction {
  public override CompileResult Execute(
      IEnumerable<FunctionArgument> arguments,
      ParsingContext context) {
    ValidateArguments(arguments, 1);
    var number = ArgToDecimal(arguments, 0);
    var nDecimals = 2;
    var noCommas = false;
    if (arguments.Count() > 1) {
      nDecimals = ArgToInt(arguments, 1);
    }
    if (arguments.Count() > 2) {
      noCommas = ArgToBool(arguments, 2);
    }
    var format = (noCommas ? "F" : "N") + nDecimals.ToString(CultureInfo.InvariantCulture);
    if (nDecimals < 0) {
      number = number - (number % (System.Math.Pow(10, nDecimals * -1)));
      number = System.Math.Floor(number);
      format = noCommas ? "F0" : "N0";
    }
    var retVal = number.ToString(format);
    return CreateResult(retVal, DataType.String);
  }
}