/*******************************************************************************
 * You may amend and distribute as you like, but don't remove this header!
 *
 * EPPlus provides server-side generation of Excel 2007/2010 spreadsheets.
 * See http://www.codeplex.com/EPPlus for details.
 *
 * 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       		        2011-01-08
 * Jan Källman		    License changed GPL-->LGPL  2011-12-27
 *******************************************************************************/

using System;
using System.Globalization;
using System.Xml;

namespace AppsheetEpplus;

internal class ExcelDataValidationFormulaDateTime
    : ExcelDataValidationFormulaValue<DateTime?>,
      IExcelDataValidationFormulaDateTime {
  public ExcelDataValidationFormulaDateTime(
      XmlNamespaceManager namespaceManager,
      XmlNode topNode,
      string formulaPath)
      : base(namespaceManager, topNode, formulaPath) {
    var value = GetXmlNodeString(formulaPath);
    if (!string.IsNullOrEmpty(value)) {
      if (double.TryParse(value, NumberStyles.Any, CultureInfo.InvariantCulture, out var oADate)) {
        Value = DateTime.FromOADate(oADate);
      } else {
        ExcelFormula = value;
      }
    }
  }

  protected override string GetValueAsString() {
    return Value.HasValue
        ? Value.Value.ToOADate().ToString(CultureInfo.InvariantCulture)
        : string.Empty;
  }
}