/*************************************************************************************************
  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
 *************************************************************************************************
  05/03/2020         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.Engineering
{
    [FunctionMetadata(
        Category = ExcelFunctionCategory.Engineering,
        EPPlusVersion = "5.1",
        Description = "Converts a binary number to hexadecimal")]
    internal class Bin2Hex : ExcelFunction
    {
        public override int ArgumentMinLength => 1;
        public override CompileResult Execute(IList<FunctionArgument> arguments, ParsingContext context)
        {
            var number = ArgToString(arguments, 0);
            var formatString = "X";
            if(arguments.Count > 1)
            {
                var padding = ArgToInt(arguments, 1, out ExcelErrorValue e1);
                if (e1 != null) return CompileResult.GetErrorResult(e1.Type);
                if (padding < 0 ^ padding > 10) return CreateResult(eErrorType.Num);
                formatString += padding;
            }
            if (number.Length > 10) return CreateResult(eErrorType.Num);
            if (number.Length < 10)
            {
                var n = Convert.ToInt32(number, 2);
                return CreateResult(n.ToString(formatString), DataType.Decimal);
            }
            else
            {
                if (!BinaryHelper.TryParseBinaryToDecimal(number, 2, out int result)) return CreateResult(eErrorType.Num);
                var hexStr = result.ToString(formatString);
                if(result < 0)
                {
                    hexStr = PaddingHelper.EnsureLength(hexStr, 10, "F");
                }
                return CreateResult(hexStr, DataType.String);
            }
        }
    }
}
