/*******************************************************************************
 * 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		        2009-10-01
 * Jan Källman		License changed GPL-->LGPL 2011-12-16
 *******************************************************************************/

using System.Globalization;
using System.Xml;

namespace OfficeOpenXml.Style.XmlAccess;

/// <summary>
/// Xml access class for gradient fillsde
/// </summary>
public sealed class ExcelGradientFillXml : ExcelFillXml {
  internal ExcelGradientFillXml(XmlNamespaceManager nameSpaceManager)
      : base(nameSpaceManager) {
    GradientColor1 = new(nameSpaceManager);
    GradientColor2 = new(nameSpaceManager);
  }

  internal ExcelGradientFillXml(XmlNamespaceManager nsm, XmlNode topNode)
      : base(nsm, topNode) {
    Degree = GetXmlNodeDouble(_degreePath);
    Type =
        GetXmlNodeString(_typePath) == "path"
            ? ExcelFillGradientType.Path
            : ExcelFillGradientType.Linear;
    GradientColor1 = new(nsm, topNode.SelectSingleNode(_gradientColor1Path, nsm));
    GradientColor2 = new(nsm, topNode.SelectSingleNode(_gradientColor2Path, nsm));

    Top = GetXmlNodeDouble(_topPath);
    Bottom = GetXmlNodeDouble(_bottomPath);
    Left = GetXmlNodeDouble(_leftPath);
    Right = GetXmlNodeDouble(_rightPath);
  }

  private const string _typePath = "d:gradientFill/@type";

  /// <summary>
  /// Type of gradient fill.
  /// </summary>
  public ExcelFillGradientType Type { get; internal set; }

  private const string _degreePath = "d:gradientFill/@degree";

  /// <summary>
  /// Angle of the linear gradient
  /// </summary>
  public double Degree { get; internal set; }

  private const string _gradientColor1Path = "d:gradientFill/d:stop[@position=\"0\"]/d:color";

  /// <summary>
  /// Gradient color 1
  /// </summary>
  public ExcelColorXml GradientColor1 { get; private set; }

  private const string _gradientColor2Path = "d:gradientFill/d:stop[@position=\"1\"]/d:color";

  /// <summary>
  /// Gradient color 2
  /// </summary>
  public ExcelColorXml GradientColor2 { get; private set; }

  private const string _bottomPath = "d:gradientFill/@bottom";

  /// <summary>
  /// Percentage format bottom
  /// </summary>
  public double Bottom { get; internal set; }

  private const string _topPath = "d:gradientFill/@top";

  /// <summary>
  /// Percentage format top
  /// </summary>
  public double Top { get; internal set; }

  private const string _leftPath = "d:gradientFill/@left";

  /// <summary>
  /// Percentage format left
  /// </summary>
  public double Left { get; internal set; }

  private const string _rightPath = "d:gradientFill/@right";

  /// <summary>
  /// Percentage format right
  /// </summary>
  public double Right { get; internal set; }

  internal override string Id =>
    base.Id + Degree + GradientColor1.Id + GradientColor2.Id + Type + Left + Right + Bottom + Top;

  internal override ExcelFillXml Copy() {
    ExcelGradientFillXml newFill = new ExcelGradientFillXml(NameSpaceManager);
    newFill.PatternType = _fillPatternType;
    newFill.BackgroundColor = _backgroundColor.Copy();
    newFill.PatternColor = _patternColor.Copy();

    newFill.GradientColor1 = GradientColor1.Copy();
    newFill.GradientColor2 = GradientColor2.Copy();
    newFill.Type = Type;
    newFill.Degree = Degree;
    newFill.Top = Top;
    newFill.Bottom = Bottom;
    newFill.Left = Left;
    newFill.Right = Right;

    return newFill;
  }

  internal override XmlNode CreateXmlNode(XmlNode topNode) {
    TopNode = topNode;
    CreateNode("d:gradientFill");
    if (Type == ExcelFillGradientType.Path) {
      SetXmlNodeString(_typePath, "path");
    }
    if (!double.IsNaN(Degree)) {
      SetXmlNodeString(_degreePath, Degree.ToString(CultureInfo.InvariantCulture));
    }
    if (GradientColor1 != null) {
      /*** Gradient color node 1***/
      var node = TopNode.SelectSingleNode("d:gradientFill", NameSpaceManager);
      var stopNode = node.OwnerDocument.CreateElement("stop", ExcelPackage._schemaMain);
      stopNode.SetAttribute("position", "0");
      node.AppendChild(stopNode);
      var colorNode = node.OwnerDocument.CreateElement("color", ExcelPackage._schemaMain);
      stopNode.AppendChild(colorNode);
      GradientColor1.CreateXmlNode(colorNode);

      /*** Gradient color node 2***/
      stopNode = node.OwnerDocument.CreateElement("stop", ExcelPackage._schemaMain);
      stopNode.SetAttribute("position", "1");
      node.AppendChild(stopNode);
      colorNode = node.OwnerDocument.CreateElement("color", ExcelPackage._schemaMain);
      stopNode.AppendChild(colorNode);

      GradientColor2.CreateXmlNode(colorNode);
    }
    if (!double.IsNaN(Top)) {
      SetXmlNodeString(_topPath, Top.ToString("F5", CultureInfo.InvariantCulture));
    }
    if (!double.IsNaN(Bottom)) {
      SetXmlNodeString(_bottomPath, Bottom.ToString("F5", CultureInfo.InvariantCulture));
    }
    if (!double.IsNaN(Left)) {
      SetXmlNodeString(_leftPath, Left.ToString("F5", CultureInfo.InvariantCulture));
    }
    if (!double.IsNaN(Right)) {
      SetXmlNodeString(_rightPath, Right.ToString("F5", CultureInfo.InvariantCulture));
    }

    return topNode;
  }
}