﻿/*******************************************************************************
 * 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
 * ******************************************************************************
 * Jan Källman		Initial Release		        2010-06-01
 * Jan Källman		License changed GPL-->LGPL 2011-12-16
 *******************************************************************************/

using System.Xml;

namespace OfficeOpenXml.Drawing.Vml;

/// <summary>
/// The position of a VML drawing. Used for comments
/// </summary>
public class ExcelVmlDrawingPosition : XmlHelper {
  private readonly int _startPos;

  internal ExcelVmlDrawingPosition(XmlNamespaceManager ns, XmlNode topNode, int startPos)
      : base(ns, topNode) {
    _startPos = startPos;
  }

  /// <summary>
  /// Row. Zero based
  /// </summary>
  public int Row {
    get => GetNumber(2);
    set => SetNumber(2, value);
  }

  /// <summary>
  /// Row offset in pixels. Zero based
  /// </summary>
  public int RowOffset {
    get => GetNumber(3);
    set => SetNumber(3, value);
  }

  /// <summary>
  /// Column. Zero based
  /// </summary>
  public int Column {
    get => GetNumber(0);
    set => SetNumber(0, value);
  }

  /// <summary>
  /// Column offset. Zero based
  /// </summary>
  public int ColumnOffset {
    get => GetNumber(1);
    set => SetNumber(1, value);
  }

  private void SetNumber(int pos, int value) {
    string anchor = GetXmlNodeString("x:Anchor");
    string[] numbers = anchor.Split(',');
    if (numbers.Length == 8) {
      numbers[_startPos + pos] = value.ToString();
    } else {
      throw (new("Anchor element is invalid in vmlDrawing"));
    }
    SetXmlNodeString("x:Anchor", string.Join(",", numbers));
  }

  private int GetNumber(int pos) {
    string anchor = GetXmlNodeString("x:Anchor");
    string[] numbers = anchor.Split(',');
    if (numbers.Length == 8) {
      if (int.TryParse(numbers[_startPos + pos], out var ret)) {
        return ret;
      }
    }
    throw (new("Anchor element is invalid in vmlDrawing"));
  }
}