using log4net;
using System.Data.SqlClient;
using System.Data;
using Dapper;
using Dlhis.ScheduledTask.Job;

namespace Dlhis.ScheduledTask.Extensions
{
    public static class DbConnectionExtensions
    {
        private static readonly ILog log = LogManager.GetLogger(typeof(JinkoHrJob));

        public static void BulkcopyInsert<T>(this IDbConnection conn, string tableName, List<T> data)
        {
            using (var bulkcopy = new SqlBulkCopy(conn as SqlConnection))
            {
                bulkcopy.BatchSize = 10000;
                bulkcopy.BulkCopyTimeout = 60;
                bulkcopy.DestinationTableName = tableName;
                var dt = ToDataTable(data);
                foreach (DataColumn column in dt.Columns)
                {
                    bulkcopy.ColumnMappings.Add(new SqlBulkCopyColumnMapping(column.ColumnName, column.ColumnName));
                }

                bulkcopy.WriteToServer(dt);
            }
        }


        private static DataTable ToDataTable<T>(List<T> data)
        {
            var dt = new DataTable();
            var properties = typeof(T).GetProperties();//.Where(x => x.IsDefined(typeof(CopyAttribute), false));

            foreach (var property in properties)
            {
                dt.Columns.Add(property.Name, Nullable.GetUnderlyingType(property.PropertyType) ?? property.PropertyType);
            }

            foreach (var item in data)
            {
                var values = new object[properties.Length];
                for (int i = 0; i < properties.Length; i++)
                {
                    if (properties[i].PropertyType == typeof(DateTime?))
                    {
                        var o = (DateTime?)properties[i].GetValue(item);
                        if (!o.HasValue || o.Value == DateTime.MinValue)
                        {
                            o = new DateTime(1900, 1, 1);
                        }
                        values[i] = o;
                    }
                    else
                    {
                        var o = properties[i].GetValue(item);
                        values[i] = o;
                    }

                }

                dt.Rows.Add(values);
            }

            return dt;
        }



        public static void BulkcopyUpdate<T>(this IDbConnection conn, string targetTableName, List<T> data)
        {
            var tmpTable = "#tmp_" + targetTableName;
            try
            {
                //go 语法错误 ??? 
                conn.Execute($@"
if object_id('tempdb..{tmpTable}') is not null
drop table {tmpTable}");

                conn.Execute($@"
select *
into {tmpTable}
from {targetTableName} where 1=2 ;");

                conn.BulkcopyInsert(tmpTable, data);

                var properties = typeof(T).GetProperties();
                var updates = properties.Where(x => !x.Name.Equals("ename"))
                        .Where(x => !x.Name.Equals("id"))
                        .Where(x => !x.Name.Equals("timeid"))
                        .Select(x =>
                        {
                            return $"T.{x.Name}=S.{x.Name}";
                        });

                var updateScript = string.Join(",", updates);

                var merge = $@"
Merge into {targetTableName} AS T 
Using {tmpTable} AS S 
ON T.ename = S.ename
WHEN MATCHED 
THEN UPDATE  SET {updateScript} ;
";

                conn.Execute(merge);
            }
            catch (Exception ex)
            {
                log.Error($"批量更新失败:{ex.Message}", ex);
            }
            finally
            {
                conn.Execute($@"
drop table {tmpTable}
"
);
            }
        }
    }
}