/*******************************************************************************
 * 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
 * ******************************************************************************
 * Eyal Seagull        Added       		  2012-04-03
 *******************************************************************************/

using System;
using System.Collections.Immutable;
using System.Xml;

namespace AppsheetEpplus;

/// <summary>
///
/// </summary>
public abstract class ExcelConditionalFormattingRule : XmlHelper, IExcelConditionalFormattingRule {
  private eExcelConditionalFormattingRuleType? _type;
  private readonly ExcelWorksheet _worksheet;

  /// <summary>
  /// Sinalize that we are in a Cnaging Priorities opeartion so that we won't enter
  /// a recursive loop.
  /// </summary>
  private static bool _changingPriority;

  protected override ImmutableArray<string> SchemaNodeOrder =>
    ExcelWorksheet.WorksheetSchemaNodeOrder;

  /// <summary>
  /// Initialize the <see cref="ExcelConditionalFormattingRule"/>
  /// </summary>
  /// <param name="type"></param>
  /// <param name="address"></param>
  /// <param name="priority">Used also as the cfRule unique key</param>
  /// <param name="worksheet"></param>
  /// <param name="itemElementNode"></param>
  /// <param name="namespaceManager"></param>
  internal ExcelConditionalFormattingRule(
      eExcelConditionalFormattingRuleType type,
      ExcelAddress address,
      int priority,
      ExcelWorksheet worksheet,
      XmlNode itemElementNode,
      XmlNamespaceManager namespaceManager)
      : base(namespaceManager, itemElementNode) {
    ArgumentNullException.ThrowIfNull(address);
    ArgumentOutOfRangeException.ThrowIfLessThan(priority, 1);
    ArgumentNullException.ThrowIfNull(worksheet);

    _type = type;
    _worksheet = worksheet;

    if (itemElementNode == null) {
      // Create/Get the <cfRule> inside <conditionalFormatting>
      itemElementNode = CreateComplexNode(
          _worksheet.WorksheetXml.DocumentElement,
          string.Format(
              "{0}[{1}='{2}']/{1}='{2}'/{3}[{4}='{5}']/{4}='{5}'",
              //{0}
              ExcelConditionalFormattingConstants.Paths._conditionalFormatting,
              // {1}
              ExcelConditionalFormattingConstants.Paths._sqrefAttribute,
              // {2}
              address.AddressSpaceSeparated, //CF node don't what to have comma between multi addresses, use space instead.
              // {3}
              ExcelConditionalFormattingConstants.Paths._cfRule,
              //{4}
              ExcelConditionalFormattingConstants.Paths._priorityAttribute,
              //{5}
              priority));
    }

    // Point to <cfRule>
    TopNode = itemElementNode;

    Address = address;
    Priority = priority;
    Type = type;
    if (DxfId >= 0) {
      worksheet.Workbook.Styles.Dxfs[DxfId].AllowChange = true; //This Id is referenced by CF, so we can use it when we save.
      _style = worksheet.Workbook.Styles.Dxfs[DxfId].Clone(); //Clone, so it can be altered without effecting other dxf styles
    }
  }

  /// <summary>
  /// Initialize the <see cref="ExcelConditionalFormattingRule"/>
  /// </summary>
  /// <param name="type"></param>
  /// <param name="address"></param>
  /// <param name="priority"></param>
  /// <param name="worksheet"></param>
  /// <param name="namespaceManager"></param>
  internal ExcelConditionalFormattingRule(
      eExcelConditionalFormattingRuleType type,
      ExcelAddress address,
      int priority,
      ExcelWorksheet worksheet,
      XmlNamespaceManager namespaceManager)
      : this(type, address, priority, worksheet, null, namespaceManager) {}

  /// <summary>
  /// Get the &lt;cfRule&gt; node
  /// </summary>
  public XmlNode Node => TopNode;

  /// <summary>
  /// Address of the conditional formatting rule
  /// </summary>
  /// <remarks>
  /// The address is stores in a parent node called &lt;conditionalFormatting&gt; in the
  /// @sqref attribute. Excel groups rules that have the same address inside one node.
  /// </remarks>
  public ExcelAddress Address {
    get =>
      new(Node.ParentNode.Attributes[ExcelConditionalFormattingConstants.Attributes._sqref].Value);
    set {
      // Check if the address is to be changed
      if (Address.Address != value.Address) {
        // Save the old parente node
        XmlNode oldNode = Node;
        XmlNode oldParentNode = Node.ParentNode;

        // Create/Get the new <conditionalFormatting> parent node
        XmlNode newParentNode = CreateComplexNode(
            _worksheet.WorksheetXml.DocumentElement,
            string.Format(
                "{0}[{1}='{2}']/{1}='{2}'",
                //{0}
                ExcelConditionalFormattingConstants.Paths._conditionalFormatting,
                // {1}
                ExcelConditionalFormattingConstants.Paths._sqrefAttribute,
                // {2}
                value.AddressSpaceSeparated));

        // Move the <cfRule> node to the new <conditionalFormatting> parent node
        TopNode = newParentNode.AppendChild(Node);

        // Check if the old <conditionalFormatting> parent node has <cfRule> node inside it
        if (!oldParentNode.HasChildNodes) {
          // Remove the old parent node
          oldParentNode.ParentNode.RemoveChild(oldParentNode);
        }
      }
    }
  }

  /// <summary>
  /// Type of conditional formatting rule. ST_CfType §18.18.12.
  /// </summary>
  public eExcelConditionalFormattingRuleType Type {
    get {
      // Transform the @type attribute to EPPlus Rule Type (slighty diferente)
      if (_type == null) {
        _type = ExcelConditionalFormattingRuleType.GetTypeByAttrbiute(
            GetXmlNodeString(ExcelConditionalFormattingConstants.Paths._typeAttribute),
            TopNode,
            _worksheet.NameSpaceManager);
      }
      return (eExcelConditionalFormattingRuleType)_type;
    }
    internal set {
      _type = value;
      // Transform the EPPlus Rule Type to @type attribute (slighty diferente)
      SetXmlNodeString(
          ExcelConditionalFormattingConstants.Paths._typeAttribute,
          ExcelConditionalFormattingRuleType.GetAttributeByType(value),
          true);
    }
  }

  /// <summary>
  /// The priority of this conditional formatting rule. This value is used to determine
  /// which format should be evaluated and rendered. Lower numeric values are higher
  /// priority than higher numeric values, where 1 is the highest priority.
  /// </summary>
  public int Priority {
    get => GetXmlNodeInt(ExcelConditionalFormattingConstants.Paths._priorityAttribute);
    set {
      // Save the current CF rule priority
      int priority = Priority;

      // Check if the @priority is to be changed
      if (priority != value) {
        // Check if we are not already inside a "Change Priority" operation
        if (!_changingPriority) {
          if (value < 1) {
            throw new IndexOutOfRangeException(
                ExcelConditionalFormattingConstants.Errors._invalidPriority);
          }

          // Sinalize that we are already changing cfRules priorities
          _changingPriority = true;

          // Check if we lowered the priority
          if (priority > value) {
            for (int i = priority - 1; i >= value; i--) {
              var cfRule = _worksheet.ConditionalFormatting.RulesByPriority(i);

              if (cfRule != null) {
                cfRule.Priority++;
              }
            }
          } else {
            for (int i = priority + 1; i <= value; i++) {
              var cfRule = _worksheet.ConditionalFormatting.RulesByPriority(i);

              if (cfRule != null) {
                cfRule.Priority--;
              }
            }
          }

          // Sinalize that we are no longer changing cfRules priorities
          _changingPriority = false;
        }

        // Change the priority in the XML
        SetXmlNodeString(
            ExcelConditionalFormattingConstants.Paths._priorityAttribute,
            value.ToString(),
            true);
      }
    }
  }

  /// <summary>
  /// If this flag is true, no rules with lower priority shall be applied over this rule,
  /// when this rule evaluates to true.
  /// </summary>
  public bool StopIfTrue {
    get => GetXmlNodeBool(ExcelConditionalFormattingConstants.Paths._stopIfTrueAttribute);
    set =>
      SetXmlNodeString(
          ExcelConditionalFormattingConstants.Paths._stopIfTrueAttribute,
          value ? "1" : string.Empty,
          true);
  }

  /// <summary>
  /// DxfId Style Attribute
  /// </summary>
  internal int DxfId {
    get => GetXmlNodeInt(ExcelConditionalFormattingConstants.Paths._dxfIdAttribute);
    set =>
      SetXmlNodeString(
          ExcelConditionalFormattingConstants.Paths._dxfIdAttribute,
          (value == int.MinValue) ? string.Empty : value.ToString(),
          true);
  }

  internal ExcelDxfStyleConditionalFormatting _style;

  public ExcelDxfStyleConditionalFormatting Style {
    get {
      if (_style == null) {
        _style = new(NameSpaceManager, null, _worksheet.Workbook.Styles);
      }
      return _style;
    }
  }

  /// <summary>
  /// StdDev (zero is not allowed and will be converted to 1)
  /// </summary>
  public UInt16 StdDev {
    get =>
      Convert.ToUInt16(GetXmlNodeInt(ExcelConditionalFormattingConstants.Paths._stdDevAttribute));
    set =>
      SetXmlNodeString(
          ExcelConditionalFormattingConstants.Paths._stdDevAttribute,
          (value == 0) ? "1" : value.ToString(),
          true);
  }

  /// <summary>
  /// Rank (zero is not allowed and will be converted to 1)
  /// </summary>
  public UInt16 Rank {
    get =>
      Convert.ToUInt16(GetXmlNodeInt(ExcelConditionalFormattingConstants.Paths._rankAttribute));
    set =>
      SetXmlNodeString(
          ExcelConditionalFormattingConstants.Paths._rankAttribute,
          (value == 0) ? "1" : value.ToString(),
          true);
  }

  /// <summary>
  /// AboveAverage
  /// </summary>
  internal protected bool? AboveAverage {
    get {
      bool? aboveAverage = GetXmlNodeBoolNullable(
          ExcelConditionalFormattingConstants.Paths._aboveAverageAttribute);

      // Above Avarege if TRUE or if attribute does not exists
      return (aboveAverage == true) || (aboveAverage == null);
    }
    set {
      string aboveAverageValue = string.Empty;

      // Only the types that needs the @AboveAverage
      if ((_type == eExcelConditionalFormattingRuleType.BelowAverage)
          || (_type == eExcelConditionalFormattingRuleType.BelowOrEqualAverage)
          || (_type == eExcelConditionalFormattingRuleType.BelowStdDev)) {
        aboveAverageValue = "0";
      }

      SetXmlNodeString(
          ExcelConditionalFormattingConstants.Paths._aboveAverageAttribute,
          aboveAverageValue,
          true);
    }
  }

  /// <summary>
  /// EqualAverage
  /// </summary>
  internal protected bool? EqualAverage {
    get {
      bool? equalAverage = GetXmlNodeBoolNullable(
          ExcelConditionalFormattingConstants.Paths._equalAverageAttribute);

      // Equal Avarege only if TRUE
      return (equalAverage == true);
    }
    set {
      string equalAverageValue = string.Empty;

      // Only the types that needs the @EqualAverage
      if ((_type == eExcelConditionalFormattingRuleType.AboveOrEqualAverage)
          || (_type == eExcelConditionalFormattingRuleType.BelowOrEqualAverage)) {
        equalAverageValue = "1";
      }

      SetXmlNodeString(
          ExcelConditionalFormattingConstants.Paths._equalAverageAttribute,
          equalAverageValue,
          true);
    }
  }

  /// <summary>
  /// Bottom attribute
  /// </summary>
  internal protected bool? Bottom {
    get {
      bool? bottom = GetXmlNodeBoolNullable(
          ExcelConditionalFormattingConstants.Paths._bottomAttribute);

      // Bottom if TRUE
      return (bottom == true);
    }
    set {
      string bottomValue = string.Empty;

      // Only the types that needs the @Bottom
      if ((_type == eExcelConditionalFormattingRuleType.Bottom)
          || (_type == eExcelConditionalFormattingRuleType.BottomPercent)) {
        bottomValue = "1";
      }

      SetXmlNodeString(
          ExcelConditionalFormattingConstants.Paths._bottomAttribute,
          bottomValue,
          true);
    }
  }

  /// <summary>
  /// Percent attribute
  /// </summary>
  internal protected bool? Percent {
    get {
      bool? percent = GetXmlNodeBoolNullable(
          ExcelConditionalFormattingConstants.Paths._percentAttribute);

      // Bottom if TRUE
      return (percent == true);
    }
    set {
      string percentValue = string.Empty;

      // Only the types that needs the @Bottom
      if ((_type == eExcelConditionalFormattingRuleType.BottomPercent)
          || (_type == eExcelConditionalFormattingRuleType.TopPercent)) {
        percentValue = "1";
      }

      SetXmlNodeString(
          ExcelConditionalFormattingConstants.Paths._percentAttribute,
          percentValue,
          true);
    }
  }

  /// <summary>
  /// TimePeriod
  /// </summary>
  internal protected eExcelConditionalFormattingTimePeriodType TimePeriod {
    get =>
      ExcelConditionalFormattingTimePeriodType.GetTypeByAttribute(
          GetXmlNodeString(ExcelConditionalFormattingConstants.Paths._timePeriodAttribute));
    set =>
      SetXmlNodeString(
          ExcelConditionalFormattingConstants.Paths._timePeriodAttribute,
          ExcelConditionalFormattingTimePeriodType.GetAttributeByType(value),
          true);
  }

  /// <summary>
  /// Operator
  /// </summary>
  internal protected eExcelConditionalFormattingOperatorType Operator {
    get =>
      ExcelConditionalFormattingOperatorType.GetTypeByAttribute(
          GetXmlNodeString(ExcelConditionalFormattingConstants.Paths._operatorAttribute));
    set =>
      SetXmlNodeString(
          ExcelConditionalFormattingConstants.Paths._operatorAttribute,
          ExcelConditionalFormattingOperatorType.GetAttributeByType(value),
          true);
  }

  /// <summary>
  /// Formula
  /// </summary>
  public string Formula {
    get => GetXmlNodeString(ExcelConditionalFormattingConstants.Paths._formula);
    set => SetXmlNodeString(ExcelConditionalFormattingConstants.Paths._formula, value);
  }

  /// <summary>
  /// Formula2
  /// </summary>
  public string Formula2 {
    get =>
      GetXmlNodeString(
          string.Format(
              "{0}[position()=2]",
              // {0}
              ExcelConditionalFormattingConstants.Paths._formula));
    set {
      // Create/Get the first <formula> node (ensure that it exists)
      var firstNode = CreateComplexNode(
          TopNode,
          string.Format(
              "{0}[position()=1]",
              // {0}
              ExcelConditionalFormattingConstants.Paths._formula));

      // Create/Get the seconde <formula> node (ensure that it exists)
      var secondNode = CreateComplexNode(
          TopNode,
          string.Format(
              "{0}[position()=2]",
              // {0}
              ExcelConditionalFormattingConstants.Paths._formula));

      // Save the formula in the second <formula> node
      secondNode.InnerText = value;
    }
  }
}