We use log4net, please remove from the code if you do not use log4net

namespace Upac.Core.Packager.Actions
{
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Xml;

    using log4net;

    using umbraco.BusinessLogic;
    using umbraco.DataLayer;
    using umbraco.cms.businesslogic.datatype;
    using umbraco.cms.businesslogic.packager.standardPackageActions;
    using umbraco.interfaces;

    public class AddMacroAliasToMacroPicker : IPackageAction
    {
        #region Fields

        private static readonly ILog log = LogManager.GetLogger(typeof(AddMacroAliasToMacroPicker));

        private readonly Guid macroPiackerDataTypeId = new Guid("2b4a6034-7063-47b0-9c4b-08bf1f23b3e2");

        #endregion Fields

        #region Methods

        public static string GetAttributeValueFromNode(XmlNode node, string attributeName)
        {
            return (node.Attributes[attributeName] == null) ? string.Empty : node.Attributes[attributeName].InnerText;
        }

        public string Alias()
        {
            return "AddMacroAliasToMacroPicker";
        }

        public bool Execute(string packageName, XmlNode xmlData)
        {
            log.Info("AddMacroAliasToMacroPicker action started");
            string macroAlias = GetAttributeValueFromNode(xmlData, "macroAliasToAdd");
            string dataTypeName = GetAttributeValueFromNode(xmlData, "dataTypeNameToUpdate");
            if (!string.IsNullOrEmpty(macroAlias) && !string.IsNullOrEmpty(dataTypeName))
            {
                log.InfoFormat("Add macro alias: {0} to data type with name: {1}", macroAlias, dataTypeName);
                DataTypeDefinition[] definitions = DataTypeDefinition.GetAll();
                DataTypeDefinition datatypeToUpdate = definitions.SingleOrDefault(dt => dt.Text == dataTypeName);

                if (datatypeToUpdate == null)
                {
                    log.ErrorFormat("Data type with name '{0}' not found!", dataTypeName);
                    return false;
                }

                if (datatypeToUpdate.DataType.Id != macroPiackerDataTypeId)
                {
                    log.ErrorFormat("Data type with name '{0}' has wrong data type id: {1} should be: {2}!", dataTypeName, datatypeToUpdate.DataType.Id, macroPiackerDataTypeId);
                    return false;
                }

                List<string> values = GetPreValues(datatypeToUpdate.Id);
                if (!values.Contains(macroAlias))
                {
                    log.InfoFormat("Adding macro alias: {0} to data type with name: {1}", macroAlias, dataTypeName);
                    values.Add(macroAlias);
                    string[] valuesAsArray = values.ToArray();
                    string newDataTypePrevalue = string.Join(",", valuesAsArray);
                    SavePreValues(newDataTypePrevalue, datatypeToUpdate.Id);
                    log.InfoFormat("Macro alias: {0} added to data type with name: {1}", macroAlias, dataTypeName);
                }
            }
            log.Info("AddMacroAliasToMacroPicker action ended");
            return true;
        }

        public XmlNode SampleXml()
        {
            return helper.parseStringToXmlNode(string.Format("<Action runat=\"install\" undo=\"false\" alias=\"{0}\" macroAliasToAdd=\"CPalm.OEmed\" dataTypeNameToUpdate=\"Macro Picker\" />", Alias()));
        }

        public bool Undo(string packageName, XmlNode xmlData)
        {
            return false;
        }

        private static List<string> GetPreValues(int dataDefinitionID)
        {
            List<string> list = new List<string>();
            string str = string.Format("{0}", Application.SqlHelper.ExecuteScalar<string>("select value from cmsDataTypePreValues where datatypenodeid = @datatypenodeid", new IParameter[] { Application.SqlHelper.CreateParameter("@datatypenodeid", dataDefinitionID) }));
            list.AddRange(str.Split(new char[] { ',' }));
            return list;
        }

        private static void SavePreValues(string data, int dataDefinitionID)
        {
            Application.SqlHelper.ExecuteNonQuery("delete from cmsDataTypePreValues where datatypenodeid = @dtdefid", new IParameter[] { Application.SqlHelper.CreateParameter("@dtdefid", dataDefinitionID) });
            Application.SqlHelper.ExecuteNonQuery("insert into cmsDataTypePreValues (datatypenodeid,[value],sortorder,alias) values (@dtdefid,@value,0,'')", new IParameter[] { Application.SqlHelper.CreateParameter("@dtdefid", dataDefinitionID), Application.SqlHelper.CreateParameter("@value", data) });
        }

        #endregion Methods
    }
}

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