using System;
using System.Collections.Generic;
using System.Data;
using System.Data.SqlClient;
using DTS.Common.Storage;
using DTS.Common.Utilities.Logging;

// ReSharper disable CheckNamespace
// ReSharper disable InconsistentNaming

namespace DTS.Common.Settings
{
    public class GlobalSetting : Setting
    {
        private const string SYSTEM = "SYSTEM";

        protected GlobalSetting()
            : base("", PropertyTypes.Global, "", SYSTEM)
        {
        }
        public GlobalSetting(string id, string defaultPropertyValue)
            : base(id, PropertyTypes.Global, defaultPropertyValue, SYSTEM)
        {
        }
        public static GlobalSetting ReadXML(System.Xml.XmlElement root)
        {
            var gs = new GlobalSetting();
            foreach (var node in root.ChildNodes)
            {
                if (node is System.Xml.XmlElement element) { ProcessXMLElement(element, ref gs); }
            }
            return gs;
        }

        public enum XMLFields
        {
            NAME,
            VALUE
        };
        private static void ProcessXMLElement(System.Xml.XmlElement node, ref GlobalSetting gs)
        {
            XMLFields field;
            if (Enum.TryParse(node.Name, out field))
            {
                switch (field)
                {
                    case XMLFields.NAME: gs._propertyId = node.InnerText; break;
                    case XMLFields.VALUE: gs._propertyValue = node.InnerText; break;
                    default:
                        // TODO: handle exception properly
                        throw new NotImplementedException("Unsupported xml tag for GlobalSetting: " + field.ToString());

                }
            }
        }

        public class NullDefaultValueException : NullReferenceException { }

        public static GlobalSetting[] GetAllGlobalSettings()
        {
            var list = new List<GlobalSetting>();
            try
            {
                using (var cmd = DbOperations.GetSQLCommand(true))
                {
                    try
                    {
                        cmd.CommandType = CommandType.StoredProcedure;
                        cmd.CommandText = DbOperationsEnum.StoredProcedure.sp_SettingsGet.ToString();
                        cmd.Parameters.Add(new SqlParameter("@UserId", SqlDbType.NVarChar) { Value = SYSTEM });
                        cmd.Parameters.Add(new SqlParameter("@PropertyId", SqlDbType.NVarChar) { Value = DBNull.Value });

                        var reader = cmd.ExecuteReader();
                        while (reader.Read())
                        {
                            var gs = new GlobalSetting()
                            {
                                _propertyId = Convert.ToString(reader["PropertyId"]),
                                _propertyType = Convert.ToInt32(reader["PropertyType"]),
                                _propertyValue = Convert.ToString(reader["PropertyValue"])
                            };
                            list.Add(gs);
                        }
                    }
                    finally { cmd.Connection.Dispose(); }
                }
            }
            catch (Exception ex)
            {
                APILogger.Log($"Failed to retrieve global settings", ex);
            }
            return list.ToArray();
        }
        protected override void GetPropertyValue(string defaultValue)
        {
            try
            {
                using (var cmd = DbOperations.GetSQLCommand(true))
                {
                    try
                    {
                        cmd.CommandType = CommandType.StoredProcedure;
                        cmd.CommandText = DbOperationsEnum.StoredProcedure.sp_SettingsGet.ToString();
                        cmd.Parameters.Add(new SqlParameter("@UserId", SqlDbType.NVarChar) { Value = SYSTEM });
                        cmd.Parameters.Add(new SqlParameter("@PropertyId", SqlDbType.NVarChar) { Value = PropertyId });

                        var reader = cmd.ExecuteReader();
                        if (reader.Read())
                        {
                            _propertyValue = Convert.ToString(reader[DbOperations.Settings.UserFields.PropertyValue.ToString()]);
                        }
                        else
                        {
                            //null being passed in will create an exception when we try to StoreInDB
                            //handle this as an explicit case
                            //26754 Exceptions thrown and eaten when Export is clicked in Export Settings
                            if (null == defaultValue)
                            {
                                throw new NullDefaultValueException();
                            }
                            _propertyValue = defaultValue;
                            StoreInDB();
                        }
                    }
                    finally { cmd.Connection.Dispose(); }
                }
            }
            catch (NullDefaultValueException)
            {
                //we tried to retrieve a global setting, it didn't exist in the db, we don't have a default value
                //return this as an explicit case
                //26754 Exceptions thrown and eaten when Export is clicked in Export Settings
                throw;
            }
            catch (Exception ex)
            {
                APILogger.Log($"Failed to retrieve global setting {PropertyId} - {defaultValue}", ex);
                _propertyValue = defaultValue;
            }
        }
    }
}