using System;
using System.Data.Common;
using System.Data.SqlClient;
using System.Diagnostics;
using System.Runtime.CompilerServices;
using System.Threading.Tasks;

namespace Gestor.Infrastructure.Helpers
{
	internal static class SqlDataReaderHelper
	{
		public static bool FieldIsNull(this SqlDataReader rd, string fieldName)
		{
			return rd.IsDBNull(rd.GetOrdinal(fieldName));
		}

		public static async Task<bool> FieldIsNullAsync(SqlDataReader rd, string fieldName)
		{
			return await rd.IsDBNullAsync(rd.GetOrdinal(fieldName));
		}

		public static T GetFieldValue<T>(this SqlDataReader rd, string fieldName, bool normalizeNull = true, bool transformField = true)
		{
			Type type = rd[fieldName].GetType();
			Type type1 = typeof(T);
			if (type == typeof(DBNull))
			{
				if (normalizeNull && (!type1.IsGenericType || !(type1.GetGenericTypeDefinition() == typeof(Nullable<>))))
				{
					if (type1 == typeof(int) || type1 == typeof(double) || type1 == typeof(decimal) || type1 == typeof(long))
					{
						return (T)Convert.ChangeType(0, type1);
					}
					if (type1 == typeof(DateTime))
					{
						return (T)Convert.ChangeType(DateTime.MinValue, type1);
					}
					if (type1 == typeof(bool))
					{
						return (T)Convert.ChangeType(false, type1);
					}
				}
				return default(T);
			}
			Type underlyingType = Nullable.GetUnderlyingType(type1) ?? type1;
			if (type == underlyingType)
			{
				return (T)rd[fieldName];
			}
			if (!transformField)
			{
				return (T)rd[fieldName];
			}
			object item = rd[fieldName];
			if (underlyingType.IsEnum)
			{
				item = Enum.Parse(underlyingType, item.ToString());
			}
			if (type == typeof(string) && underlyingType == typeof(bool))
			{
				item = (string)item == "1";
			}
			return (T)Convert.ChangeType(item, underlyingType);
		}
	}
}