EPPlus/FormulaParsing/Excel/Functions/Math/SumProduct.cs

/* Copyright (C) 2011  Jan Källman
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.

 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Lesser General Public License for more details.
 *
 * The GNU Lesser General Public License can be viewed at http://www.opensource.org/licenses/lgpl-license.php
 * If you unfamiliar with this license or have questions about it, here is an http://www.gnu.org/licenses/gpl-faq.html
 *
 * All code and executables are provided "as is" with no warranty either express or implied.
 * The author accepts no liability for any damage or loss of business that this product may cause.
 *
 * Code change notes:
 *
 * Author							Change						Date
 *******************************************************************************
 * Mats Alm   		                Added		                2013-12-03
 *******************************************************************************/

using System;
using System.Collections.Generic;
using System.Linq;
using OfficeOpenXml.FormulaParsing.Exceptions;
using OfficeOpenXml.FormulaParsing.ExpressionGraph;

namespace OfficeOpenXml.FormulaParsing.Excel.Functions.Math;

public class SumProduct : ExcelFunction {
  public override CompileResult Execute(
      IEnumerable<FunctionArgument> arguments,
      ParsingContext context) {
    ValidateArguments(arguments, 1);
    double result = 0d;
    List<List<double>> results = new List<List<double>>();
    foreach (var arg in arguments) {
      results.Add(new());
      var currentResult = results.Last();
      if (arg.Value is IEnumerable<FunctionArgument> value) {
        foreach (var val in value) {
          AddValue(val.Value, currentResult);
        }
      } else if (arg.Value is FunctionArgument) {
        AddValue(arg.Value, currentResult);
      } else if (arg.IsExcelRange) {
        var r = arg.ValueAsRangeInfo;
        for (int col = r.Address._fromCol; col <= r.Address._toCol; col++) {
          for (int row = r.Address._fromRow; row <= r.Address._toRow; row++) {
            AddValue(r.GetValue(row, col), currentResult);
          }
        }
      }
    }
    // Validate that all supplied lists have the same length
    var arrayLength = results.First().Count;
    foreach (var list in results) {
      if (list.Count != arrayLength) {
        throw new ExcelErrorValueException(ExcelErrorValue.Create(eErrorType.Value));
        //throw new ExcelFunctionException("All supplied arrays must have the same length", ExcelErrorCodes.Value);
      }
    }
    for (var rowIndex = 0; rowIndex < arrayLength; rowIndex++) {
      double rowResult = 1;
      for (var colIndex = 0; colIndex < results.Count; colIndex++) {
        rowResult *= results[colIndex][rowIndex];
      }
      result += rowResult;
    }
    return CreateResult(result, DataType.Decimal);
  }

  private void AddValue(object convertVal, List<double> currentResult) {
    if (IsNumeric(convertVal)) {
      currentResult.Add(Convert.ToDouble(convertVal));
    } else if (convertVal is ExcelErrorValue val) {
      throw (new ExcelErrorValueException(val));
    } else {
      currentResult.Add(0d);
    }
  }
}