using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using System.Text;

using Dapper;
using System.Data.SqlClient;

namespace DapperExtensions.SqlServerExt
{
    public static class SqlServerExt
    {
        private static readonly ConcurrentDictionary<RuntimeTypeHandle, DapperExtSqls> dapperExtsqlsDict = new ConcurrentDictionary<RuntimeTypeHandle, DapperExtSqls>();
        public static DapperExtSqls GetDapperExtSqls(Type t)
        {
            if (dapperExtsqlsDict.Keys.Contains(t.TypeHandle))
            {
                return dapperExtsqlsDict[t.TypeHandle];
            }
            else
            {
                DapperExtSqls sqls = DapperExtCommon.GetDapperExtSqls(t);

                string Fields = DapperExtCommon.GetFieldsStr(sqls.AllFieldList, "[", "]");
                string FieldsAt = DapperExtCommon.GetFieldsAtStr(sqls.AllFieldList);
                string FieldsEq = DapperExtCommon.GetFieldsEqStr(sqls.AllFieldList, "[", "]");

                string FieldsExtKey = DapperExtCommon.GetFieldsStr(sqls.ExceptKeyFieldList, "[", "]");
                string FieldsAtExtKey = DapperExtCommon.GetFieldsAtStr(sqls.ExceptKeyFieldList);
                string FieldsEqExtKey = DapperExtCommon.GetFieldsEqStr(sqls.ExceptKeyFieldList, "[", "]");

                sqls.AllFields = Fields;

                if (sqls.HasKey && sqls.IsIdentity) //有主键并且是自增
                {
                    sqls.InsertSql = string.Format("INSERT INTO [{0}]({1})VALUES({2})", sqls.TableName, FieldsExtKey, FieldsAtExtKey);
                    sqls.InsertIdentitySql = string.Format("SET IDENTITY_INSERT [{0}] ON;INSERT INTO [{0}]({1})VALUES({2});SET IDENTITY_INSERT [{0}] OFF", sqls.TableName, Fields, FieldsAt);
                }
                else
                {
                    sqls.InsertSql = string.Format("INSERT INTO [{0}]({1})VALUES({2})", sqls.TableName, Fields, FieldsAt);
                }

                if (sqls.HasKey) //含有主键
                {
                    sqls.DeleteByIdSql = string.Format("DELETE FROM [{0}] WHERE [{1}]=@id", sqls.TableName, sqls.KeyName);
                    sqls.DeleteByIdsSql = string.Format("DELETE FROM [{0}] WHERE [{1}] IN @ids", sqls.TableName, sqls.KeyName);
                    sqls.GetByIdSql = string.Format("SELECT {0} FROM [{1}] WITH(NOLOCK) WHERE [{2}]=@id", Fields, sqls.TableName, sqls.KeyName);
                    sqls.GetByIdsSql = string.Format("SELECT {0} FROM [{1}] WITH(NOLOCK) WHERE [{2}] IN @ids", Fields, sqls.TableName, sqls.KeyName);
                    sqls.UpdateByIdSql = string.Format("UPDATE [{0}] SET {1} WHERE [{2}]=@{2}", sqls.TableName, FieldsEqExtKey, sqls.KeyName);
                }
                sqls.DeleteAllSql = string.Format("DELETE FROM [{0}]", sqls.TableName);
                sqls.GetAllSql = string.Format("SELECT {0} FROM [{1}] WITH(NOLOCK)", Fields, sqls.TableName);

                dapperExtsqlsDict[t.TypeHandle] = sqls;
                return sqls;
            }
        }

        /// <summary>
        /// 新增单条记录
        /// </summary>
        public static dynamic Insert<T>(this IDbConnection conn, T entity, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            if (sqls.HasKey && sqls.IsIdentity)
            {
                switch (sqls.KeyType)
                {
                    case "Int32": return conn.ExecuteScalar<int>(sqls.InsertSql + ";SELECT @@IDENTITY", entity, transaction, commandTimeout); //int
                    case "Int64": return conn.ExecuteScalar<long>(sqls.InsertSql + ";SELECT @@IDENTITY", entity, transaction, commandTimeout); //long
                    case "Decimal": return conn.ExecuteScalar<decimal>(sqls.InsertSql + ";SELECT @@IDENTITY", entity, transaction, commandTimeout); //decimal
                    case "UInt32": return conn.ExecuteScalar<uint>(sqls.InsertSql + ";SELECT @@IDENTITY", entity, transaction, commandTimeout); //uint
                    case "UInt64": return conn.ExecuteScalar<ulong>(sqls.InsertSql + ";SELECT @@IDENTITY", entity, transaction, commandTimeout); //ulong
                    case "Double": return conn.ExecuteScalar<double>(sqls.InsertSql + ";SELECT @@IDENTITY", entity, transaction, commandTimeout); //double
                    case "Single": return conn.ExecuteScalar<float>(sqls.InsertSql + ";SELECT @@IDENTITY", entity, transaction, commandTimeout); //float
                    case "Byte": return conn.ExecuteScalar<byte>(sqls.InsertSql + ";SELECT @@IDENTITY", entity, transaction, commandTimeout);  //byte
                    case "SByte": return conn.ExecuteScalar<sbyte>(sqls.InsertSql + ";SELECT @@IDENTITY", entity, transaction, commandTimeout); //sbyte
                    case "Int16": return conn.ExecuteScalar<short>(sqls.InsertSql + ";SELECT @@IDENTITY", entity, transaction, commandTimeout); //short
                    case "UInt16": return conn.ExecuteScalar<ushort>(sqls.InsertSql + ";SELECT @@IDENTITY", entity, transaction, commandTimeout); //ushort
                    default: return conn.ExecuteScalar<dynamic>(sqls.InsertSql + ";SELECT @@IDENTITY", entity, transaction, commandTimeout); //dynamic
                }
            }
            else
            {
                return conn.Execute(sqls.InsertSql, entity, transaction, commandTimeout);
            }
        }

        /// <summary>
        /// 新增多条记录
        /// </summary>
        public static int InsertBatch<T>(this IDbConnection conn, IEnumerable<T> entitys, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            return conn.Execute(sqls.InsertSql, entitys, transaction, commandTimeout);
        }

        /// <summary>
        /// 新增(插入自增键)
        /// </summary>
        public static int InsertIdentity<T>(this IDbConnection conn, T entity, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            if (sqls.HasKey && sqls.IsIdentity)
            {
                return conn.Execute(sqls.InsertIdentitySql, entity, transaction, commandTimeout);
            }
            else
            {
                throw new ArgumentException("表" + sqls.TableName + "没有自增键，无法进行InsertIdentity。");
            }
        }


        /// <summary>
        /// 新增多条记录(插入自增键)
        /// </summary>
        public static int InsertIdentityBatch<T>(this IDbConnection conn, IEnumerable<T> entitys, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            if (sqls.HasKey && sqls.IsIdentity)
            {
                return conn.Execute(sqls.InsertIdentitySql, entitys, transaction, commandTimeout);
            }
            else
            {
                throw new ArgumentException("表" + sqls.TableName + "没有自增键，无法进行InsertIdentity。");
            }
        }

        /// <summary>
        /// 根据Id，若存在则更新，不存在就插入
        /// </summary>
        public static dynamic InsertOrUpdate<T>(this IDbConnection conn, T entity, string updateFields = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            if (sqls.HasKey)
            {
                int result = UpdateById<T>(conn, entity, updateFields, transaction, commandTimeout);
                if (result == 0)
                    return Insert<T>(conn, entity, transaction, commandTimeout);
                return result;
            }
            else
            {
                throw new ArgumentException("表" + sqls.TableName + "没有主键，无法进行InsertOrUpdate。");
            }
        }

        /// <summary>
        /// 根据Id，若存在则更新，不存在就插入，连id都一起插入
        /// </summary>
        public static dynamic InsertOrUpdateIdentity<T>(this IDbConnection conn, T entity, string updateFields = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            if (sqls.HasKey && sqls.IsIdentity)
            {
                int result = UpdateById<T>(conn, entity, updateFields, transaction, commandTimeout);
                if (result == 0)
                    return InsertIdentity<T>(conn, entity, transaction, commandTimeout);
                return result;
            }
            else
            {
                throw new ArgumentException("表" + sqls.TableName + "没有自增键，无法进行InsertOrUpdateIdentity。");
            }
        }


        /// <summary>
        /// 根据主键返回实体Base
        /// returnFields需要返回的列，用逗号隔开。默认null，返回所有列
        /// </summary>
        private static T GetByIdBase<T>(this IDbConnection conn, Type t, dynamic id, string returnFields = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(t);
            if (sqls.HasKey)
            {
                DynamicParameters dpar = new DynamicParameters();
                dpar.Add("@id", id);
                if (returnFields == null)
                {
                    return conn.QueryFirstOrDefault<T>(sqls.GetByIdSql, dpar, transaction, commandTimeout);
                }
                else
                {
                    string sql = string.Format("SELECT {0} FROM [{1}] WITH(NOLOCK) WHERE [{2}]=@id", returnFields, sqls.TableName, sqls.KeyName);
                    return conn.QueryFirstOrDefault<T>(sql, dpar, transaction, commandTimeout);
                }
            }
            else
            {
                throw new ArgumentException("表" + sqls.TableName + "没有主键，无法GetById。");
            }
        }

        /// <summary>
        /// 根据主键返dynamic
        /// returnFields需要返回的列，用逗号隔开。默认null，返回所有列
        /// </summary>
        public static dynamic GetByIdDynamic<T>(this IDbConnection conn, dynamic id, string returnFields = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            if (sqls.HasKey)
            {
                DynamicParameters dpar = new DynamicParameters();
                dpar.Add("@id", id);
                if (returnFields == null)
                {
                    return conn.QueryFirstOrDefault(sqls.GetByIdSql, dpar, transaction, commandTimeout);
                }
                else
                {
                    string sql = string.Format("SELECT {0} FROM [{1}] WITH(NOLOCK) WHERE [{2}]=@id", returnFields, sqls.TableName, sqls.KeyName);
                    return conn.QueryFirstOrDefault(sql, dpar, transaction, commandTimeout);
                }
            }
            else
            {
                throw new ArgumentException("表" + sqls.TableName + "没有主键，无法GetByIdDynamic。");
            }
        }

        /// <summary>
        /// 根据主键返回实体
        /// returnFields需要返回的列，用逗号隔开。默认null，返回所有列
        /// </summary>
        public static T GetById<T>(this IDbConnection conn, dynamic id, string returnFields = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return GetByIdBase<T>(conn, typeof(T), id, returnFields, transaction, commandTimeout);
        }

        /// <summary>
        /// 根据主键返回任意类型实体
        /// returnFields需要返回的列，用逗号隔开。默认null，返回所有列
        /// </summary>
        public static T GetById<Table, T>(this IDbConnection conn, dynamic id, string returnFields = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return GetByIdBase<T>(conn, typeof(Table), id, returnFields, transaction, commandTimeout);
        }

        /// <summary>
        /// 根据主键ids返回实体列表
        /// returnFields需要返回的列，用逗号隔开。默认null，返回所有列
        /// </summary>
        private static IEnumerable<T> GetByIdsBase<T>(this IDbConnection conn, Type t, object ids, string returnFields = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            if (DapperExtCommon.ObjectIsEmpty(ids))
                return new List<T>();

            DapperExtSqls sqls = GetDapperExtSqls(t);
            if (sqls.HasKey)
            {
                DynamicParameters dpar = new DynamicParameters();
                dpar.Add("@ids", ids);
                if (returnFields == null)
                {
                    return conn.Query<T>(sqls.GetByIdsSql, dpar, transaction, true, commandTimeout);
                }
                else
                {
                    string sql = string.Format("SELECT {0} FROM [{1}] WITH(NOLOCK) WHERE [{2}] IN @ids", returnFields, sqls.TableName, sqls.KeyName);
                    return conn.Query<T>(sql, dpar, transaction, true, commandTimeout);
                }
            }
            else
            {
                throw new ArgumentException("表" + sqls.TableName + "没有主键，无法GetByIds。");
            }
        }

        /// <summary>
        /// 根据主键ids返回dynamic列表
        /// returnFields需要返回的列，用逗号隔开。默认null，返回所有列
        /// </summary>
        public static IEnumerable<dynamic> GetByIdsDynamic<T>(this IDbConnection conn, object ids, string returnFields = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            if (DapperExtCommon.ObjectIsEmpty(ids))
                return new List<dynamic>();

            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            if (sqls.HasKey)
            {
                DynamicParameters dpar = new DynamicParameters();
                dpar.Add("@ids", ids);
                if (returnFields == null)
                {
                    return conn.Query(sqls.GetByIdsSql, dpar, transaction, true, commandTimeout);
                }
                else
                {
                    string sql = string.Format("SELECT {0} FROM [{1}] WITH(NOLOCK) WHERE [{2}] IN @ids", returnFields, sqls.TableName, sqls.KeyName);
                    return conn.Query(sql, dpar, transaction, true, commandTimeout);
                }
            }
            else
            {
                throw new ArgumentException("表" + sqls.TableName + "没有主键，无法GetByIdsDynamic。");
            }
        }

        /// <summary>
        /// 根据主键ids返回任意类型实体列表
        /// returnFields需要返回的列，用逗号隔开。默认null，返回所有列
        /// </summary>
        public static IEnumerable<T> GetByIds<T>(this IDbConnection conn, object ids, string returnFields = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return GetByIdsBase<T>(conn, typeof(T), ids, returnFields, transaction, commandTimeout);
        }

        /// <summary>
        /// 根据主键ids返回任意类型实体列表
        /// returnFields需要返回的列，用逗号隔开。默认null，返回所有列
        /// </summary>
        public static IEnumerable<T> GetByIds<Table, T>(this IDbConnection conn, object ids, string returnFields = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return GetByIdsBase<T>(conn, typeof(Table), ids, returnFields, transaction, commandTimeout);
        }

        /// <summary>
        /// 返回整张表数据
        /// returnFields需要返回的列，用逗号隔开。默认null，返回所有列
        /// </summary>
        private static IEnumerable<T> GetAllBase<T>(this IDbConnection conn, Type t, string returnFields = null, string orderby = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(t);
            if (returnFields == null)
            {
                return conn.Query<T>(sqls.GetAllSql + " " + orderby, null, transaction, true, commandTimeout);
            }
            else
            {
                string sql = string.Format("SELECT {0} FROM [{1}] WITH(NOLOCK) " + orderby, returnFields, sqls.TableName);
                return conn.Query<T>(sql, null, transaction, true, commandTimeout);
            }
        }

        /// <summary>
        /// 返回整张表数据
        /// returnFields需要返回的列，用逗号隔开。默认null，返回所有列
        /// </summary>
        public static IEnumerable<dynamic> GetAllDynamic<T>(this IDbConnection conn, string returnFields = null, string orderby = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            if (returnFields == null)
            {
                return conn.Query(sqls.GetAllSql + " " + orderby, null, transaction, true, commandTimeout);
            }
            else
            {
                string sql = string.Format("SELECT {0} FROM [{1}] WITH(NOLOCK) " + orderby, returnFields, sqls.TableName);
                return conn.Query(sql, null, transaction, true, commandTimeout);
            }
        }

        /// <summary>
        /// 返回整张表数据
        /// returnFields需要返回的列，用逗号隔开。默认null，返回所有列
        /// </summary>
        public static IEnumerable<T> GetAll<T>(this IDbConnection conn, string returnFields = null, string orderby = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return GetAllBase<T>(conn, typeof(T), returnFields, orderby, transaction, commandTimeout);
        }

        /// <summary>
        /// 返回整张表任意类型数据
        /// returnFields需要返回的列，用逗号隔开。默认null，返回所有列
        /// </summary>
        public static IEnumerable<T> GetAll<Table, T>(this IDbConnection conn, string returnFields = null, string orderby = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return GetAllBase<T>(conn, typeof(Table), returnFields, orderby, transaction, commandTimeout);
        }

        /// <summary>
        /// 根据主键删除数据
        /// </summary>
        public static int DeleteById<T>(this IDbConnection conn, dynamic id, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            if (sqls.HasKey)
            {
                DynamicParameters dpar = new DynamicParameters();
                dpar.Add("@id", id);
                return conn.Execute(sqls.DeleteByIdSql, dpar, transaction, commandTimeout);
            }
            else
            {
                throw new ArgumentException("表" + sqls.TableName + "没有主键，无法DeleteById。");
            }
        }

        /// <summary>
        /// 根据主键批量删除数据
        /// </summary>
        public static int DeleteByIds<T>(this IDbConnection conn, object ids, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            if (DapperExtCommon.ObjectIsEmpty(ids))
                return 0;

            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            if (sqls.HasKey)
            {
                DynamicParameters dpar = new DynamicParameters();
                dpar.Add("@ids", ids);
                return conn.Execute(sqls.DeleteByIdsSql, dpar, transaction, commandTimeout);
            }
            else
            {
                throw new ArgumentException("表" + sqls.TableName + "没有主键，无法DeleteById。");
            }
        }

        /// <summary>
        /// 删除整张表数据
        /// </summary>
        public static int DeleteAll<T>(this IDbConnection conn, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            return conn.Execute(sqls.DeleteAllSql, null, transaction, commandTimeout);
        }

        /// <summary>
        /// 根据条件删除
        /// </summary>
        public static int DeleteByWhere<T>(this IDbConnection conn, string where, object param = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            string sql = string.Format("DELETE FROM [{0}] {1}", sqls.TableName, where);
            return conn.Execute(sql, param, transaction, commandTimeout);
        }

        /// <summary>
        /// 根据主键修改数据
        /// </summary>
        public static int UpdateById<T>(this IDbConnection conn, T entity, string updateFields = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            if (sqls.HasKey)
            {
                if (updateFields == null)
                {
                    return conn.Execute(sqls.UpdateByIdSql, entity, transaction, commandTimeout);
                }
                else
                {
                    string updateList = DapperExtCommon.GetFieldsEqStr(updateFields.Split(',').ToList(), "[", "]");
                    string sql = string.Format("UPDATE [{0}] SET {1} WHERE [{2}]=@{2}", sqls.TableName, updateList, sqls.KeyName);
                    return conn.Execute(sql, entity, transaction, commandTimeout);
                }
            }
            else
            {
                throw new ArgumentException("表" + sqls.TableName + "没有主键，无法UpdateById。");
            }
        }

        /// <summary>
        /// 根据主键修改数据(批量修改)
        /// </summary>
        public static int UpdateByIdBatch<T>(this IDbConnection conn, IEnumerable<T> entitys, string updateFields = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            if (sqls.HasKey)
            {
                if (updateFields == null)
                {
                    return conn.Execute(sqls.UpdateByIdSql, entitys, transaction, commandTimeout);
                }
                else
                {
                    string updateList = DapperExtCommon.GetFieldsEqStr(updateFields.Split(',').ToList(), "[", "]");
                    string sql = string.Format("UPDATE [{0}] SET {1} WHERE [{2}]=@{2}", sqls.TableName, updateList, sqls.KeyName);
                    return conn.Execute(sql, entitys, transaction, commandTimeout);
                }
            }
            else
            {
                throw new ArgumentException("表" + sqls.TableName + "没有主键，无法UpdateById。");
            }
        }

        /// <summary>
        /// 根据条件修改数据
        /// </summary>
        public static int UpdateByWhere<T>(this IDbConnection conn, string where, string updateFields, object entity, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            updateFields = DapperExtCommon.GetFieldsEqStr(updateFields.Split(',').ToList(), "[", "]");
            string sql = string.Format("UPDATE [{0}] SET {1} {2}", sqls.TableName, updateFields, where);
            return conn.Execute(sql, entity, transaction, commandTimeout);
        }

        /// <summary>
        /// 获取总数
        /// </summary>
        /// <returns></returns>
        public static int GetTotal<T>(this IDbConnection conn, string where = null, object param = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            string sql = string.Format("SELECT COUNT(1) FROM [{0}] WITH(NOLOCK) {1}", sqls.TableName, where);
            return conn.ExecuteScalar<int>(sql, param, transaction, commandTimeout);
        }

        /// <summary>
        /// Base获取数据,使用skip 和take
        /// </summary>
        /// <returns></returns>
        private static IEnumerable<T> GetBySkipBase<T>(this IDbConnection conn, Type t, int skip, int take, string returnFields = null, string where = null, object param = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(t);
            if (returnFields == null)
                returnFields = sqls.AllFields;

            if (orderBy == null)
            {
                if (sqls.HasKey)
                {
                    orderBy = string.Format("ORDER BY [{0}] DESC", sqls.KeyName);
                }
                else
                {
                    orderBy = string.Format("ORDER BY [{0}]", sqls.AllFieldList.First());
                }
            }

            StringBuilder sb = new StringBuilder();
            if (skip == 0) //第一页,使用Top语句
            {
                sb.AppendFormat("SELECT TOP ({0}) {1} FROM [{2}] WITH(NOLOCK) {3} {4}", take, returnFields, sqls.TableName, where, orderBy);
            }
            else //使用ROW_NUMBER()
            {
                sb.AppendFormat("WITH cte AS(SELECT ROW_NUMBER() OVER({0}) AS rownum,{1} FROM [{2}] WITH(NOLOCK) {3})", orderBy, returnFields, sqls.TableName, where);
                if (returnFields.Contains(" AS") || returnFields.Contains(" as"))
                {
                    sb.AppendFormat("SELECT * FROM cte WHERE cte.rownum BETWEEN {1} AND {2}", returnFields, skip + 1, skip + take);
                }
                else
                {
                    sb.AppendFormat("SELECT {0} FROM cte WHERE cte.rownum BETWEEN {1} AND {2}", returnFields, skip + 1, skip + take);
                }
            }
            return conn.Query<T>(sb.ToString(), param, transaction, true, commandTimeout);
        }

        /// <summary>
        /// 获取dynamic数据,使用skip 和take
        /// </summary>
        /// <returns></returns>
        public static IEnumerable<dynamic> GetBySkipDynamic<T>(this IDbConnection conn, int skip, int take, string returnFields = null, string where = null, object param = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            if (returnFields == null)
                returnFields = sqls.AllFields;

            if (orderBy == null)
            {
                if (sqls.HasKey)
                {
                    orderBy = string.Format("ORDER BY [{0}] DESC", sqls.KeyName);
                }
                else
                {
                    orderBy = string.Format("ORDER BY [{0}]", sqls.AllFieldList.First());
                }
            }

            StringBuilder sb = new StringBuilder();
            if (skip == 0) //第一页,使用Top语句
            {
                sb.AppendFormat("SELECT TOP ({0}) {1} FROM [{2}] WITH(NOLOCK) {3} {4}", take, returnFields, sqls.TableName, where, orderBy);
            }
            else //使用ROW_NUMBER()
            {
                sb.AppendFormat("WITH cte AS(SELECT ROW_NUMBER() OVER({0}) AS rownum,{1} FROM [{2}] WITH(NOLOCK) {3})", orderBy, returnFields, sqls.TableName, where);
                if (returnFields.Contains(" AS") || returnFields.Contains(" as"))
                {
                    sb.AppendFormat("SELECT * FROM cte WHERE cte.rownum BETWEEN {1} AND {2}", returnFields, skip + 1, skip + take);
                }
                else
                {
                    sb.AppendFormat("SELECT {0} FROM cte WHERE cte.rownum BETWEEN {1} AND {2}", returnFields, skip + 1, skip + take);
                }
            }
            return conn.Query(sb.ToString(), param, transaction, true, commandTimeout);
        }

        /// <summary>
        /// 获取dynamic分页数据
        /// </summary>
        public static IEnumerable<dynamic> GetByPageIndexDynamic<T>(this IDbConnection conn, int pageIndex, int pageSize, string returnFields = null, string where = null, object param = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            int skip = 0;
            if (pageIndex > 0)
            {
                skip = (pageIndex - 1) * pageSize;
            }
            return GetBySkipDynamic<T>(conn, skip, pageSize, returnFields, where, param, orderBy, transaction, commandTimeout);
        }

        /// <summary>
        /// 获取数据,使用skip 和take
        /// </summary>
        /// <returns></returns>
        public static IEnumerable<T> GetBySkip<T>(this IDbConnection conn, int skip, int take, string returnFields = null, string where = null, object param = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return GetBySkipBase<T>(conn, typeof(T), skip, take, returnFields, where, param, orderBy, transaction, commandTimeout);
        }

        /// <summary>
        /// 获取数据，使用skip 和take,返回任意类型数据
        /// </summary>
        /// <returns></returns>
        public static IEnumerable<T> GetBySkip<Table, T>(this IDbConnection conn, int skip, int take, string returnFields = null, string where = null, object param = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return GetBySkipBase<T>(conn, typeof(Table), skip, take, returnFields, where, param, orderBy, transaction, commandTimeout);
        }

        /// <summary>
        /// 获取分页数据
        /// </summary>
        public static IEnumerable<T> GetByPageIndex<T>(this IDbConnection conn, int pageIndex, int pageSize, string returnFields = null, string where = null, object param = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            int skip = 0;
            if (pageIndex > 0)
            {
                skip = (pageIndex - 1) * pageSize;
            }
            return GetBySkip<T>(conn, skip, pageSize, returnFields, where, param, orderBy, transaction, commandTimeout);
        }

        /// <summary>
        /// 获取分页数据,返回任意类型数据
        /// </summary>
        public static IEnumerable<T> GetByPageIndex<Table, T>(this IDbConnection conn, int pageIndex, int pageSize, string returnFields = null, string where = null, object param = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            int skip = 0;
            if (pageIndex > 0)
            {
                skip = (pageIndex - 1) * pageSize;
            }
            return GetBySkip<Table, T>(conn, skip, pageSize, returnFields, where, param, orderBy, transaction, commandTimeout);
        }

        /// <summary>
        /// 根据查询条件获取数据
        /// </summary>
        private static IEnumerable<T> GetByWhereBase<T>(this IDbConnection conn, Type t, string where = null, object param = null, string returnFields = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(t);
            if (returnFields == null)
                returnFields = sqls.AllFields;
            string sql = string.Format("SELECT {0} FROM [{1}] WITH(NOLOCK) {2} {3}", returnFields, sqls.TableName, where, orderBy);

            return conn.Query<T>(sql, param, transaction, true, commandTimeout);
        }

        /// <summary>
        /// 根据查询条件获取Dynamic数据
        /// </summary>
        public static IEnumerable<dynamic> GetByWhereDynamic<T>(this IDbConnection conn, string where = null, object param = null, string returnFields = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            if (returnFields == null)
                returnFields = sqls.AllFields;
            string sql = string.Format("SELECT {0} FROM [{1}] WITH(NOLOCK) {2} {3}", returnFields, sqls.TableName, where, orderBy);

            return conn.Query(sql, param, transaction, true, commandTimeout);
        }

        /// <summary>
        /// 根据查询条件获取数据
        /// </summary>
        public static IEnumerable<T> GetByWhere<T>(this IDbConnection conn, string where = null, object param = null, string returnFields = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return GetByWhereBase<T>(conn, typeof(T), where, param, returnFields, orderBy, transaction, commandTimeout);
        }

        /// <summary>
        /// 根据查询条件获取数据
        /// </summary>
        public static IEnumerable<T> GetByWhere<Table, T>(this IDbConnection conn, string where = null, object param = null, string returnFields = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return GetByWhereBase<T>(conn, typeof(Table), where, param, returnFields, orderBy, transaction, commandTimeout);
        }

        /// <summary>
        /// 返回DataTable
        /// </summary>
        public static DataTable GetDataTable(this IDbConnection conn, string sql, object param = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return DapperExtAllSQL.GetDataTableBase(conn, sql, param, transaction, commandTimeout);
        }

        /// <summary>
        /// 返回DataSet
        /// </summary>
        public static DataSet GetDataSet(this IDbConnection conn, string sql, object param = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return DapperExtAllSQL.GetDataSetBase(conn, sql, param, transaction, commandTimeout);
        }

        /// <summary>
        /// 获取表结构，返回DataTable
        /// </summary>
        public static DataTable GetSchemaTable<T>(this IDbConnection conn, string returnFields = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            if (returnFields == null)
            {
                returnFields = sqls.AllFields;
            }

            string sql = string.Format("SELECT TOP (0) {0} FROM [{1}] WITH(NOLOCK)", returnFields, sqls.TableName);
            return GetDataTable(conn, sql, null, transaction, commandTimeout);
        }

        /// <summary>
        /// 大批量插入数据
        /// 默认自增主键
        /// insert_identity为true时允许插入自增主键
        /// </summary>
        public static void BulkCopy<T>(this IDbConnection conn, DataTable dt, IDbTransaction transaction, string fields = null, bool insert_identity = false, int batchSize = 5000, int commandTimeout = 500000)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            SqlBulkCopyOptions option = SqlBulkCopyOptions.Default; //Default不插入主键
            if (insert_identity == true)
            {
                option = SqlBulkCopyOptions.KeepIdentity;
            }

            using (SqlBulkCopy bulkCopy = new SqlBulkCopy((SqlConnection)conn, option, (SqlTransaction)transaction))
            {
                bulkCopy.BatchSize = batchSize;
                bulkCopy.BulkCopyTimeout = commandTimeout;
                bulkCopy.DestinationTableName = sqls.TableName;
                if (fields != null)
                {

                    foreach (var item in fields.Split(','))
                    {
                        bulkCopy.ColumnMappings.Add(item, item);
                    }
                }
                else
                {

                    foreach (DataColumn col in dt.Columns)
                    {
                        bulkCopy.ColumnMappings.Add(col.ColumnName, col.ColumnName);
                    }
                }
                bulkCopy.WriteToServer(dt);
            }
        }

        /// <summary>
        /// 根据主键大批量更新数据
        /// 要求表有主键，根据主键更新数据
        /// updateFields修改个别字段一定要加上主键字段
        /// </summary>
        public static void BulkUpdate<T>(this IDbConnection conn, DataTable dt, IDbTransaction transaction, string updateFields = null, int batchSize = 5000, int commandTimeout = 500000)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            using (SqlCommand comm = (SqlCommand)conn.CreateCommand())
            {
                comm.CommandTimeout = commandTimeout;
                comm.CommandType = CommandType.Text;
                using (SqlDataAdapter adapter = new SqlDataAdapter(comm))
                {
                    using (SqlCommandBuilder commandBulider = new SqlCommandBuilder(adapter))
                    {
                        commandBulider.ConflictOption = ConflictOption.OverwriteChanges; //根据主键更新
                        adapter.UpdateBatchSize = batchSize;
                        adapter.SelectCommand.Transaction = (SqlTransaction)transaction;
                        if (updateFields == null)
                        {
                            updateFields = sqls.AllFields;
                        }
                        adapter.SelectCommand.CommandText = string.Format("SELECT TOP (0) {0} FROM [{1}]", updateFields, sqls.TableName);
                        adapter.Update(dt.GetChanges());
                    }
                }
            }


        }

        /// <summary>
        /// 获取分页数据
        /// </summary>
        private static IEnumerable<T> GetByPageBase<T>(this IDbConnection conn, Type t, int pageIndex, int pageSize, out int total, string returnFields = null, string where = null, object param = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(t);
            if (returnFields == null)
                returnFields = sqls.AllFields;

            if (orderBy == null)
            {
                if (sqls.HasKey)
                {
                    orderBy = string.Format("ORDER BY [{0}] DESC", sqls.KeyName);
                }
                else
                {
                    orderBy = string.Format("ORDER BY [{0}]", sqls.AllFieldList.First());
                }
            }

            int skip = 0;
            if (pageIndex > 0)
            {
                skip = (pageIndex - 1) * pageSize;
            }

            StringBuilder sb = new StringBuilder();
            sb.AppendFormat("DECLARE @total INT;SELECT @total = COUNT(1) FROM [{0}] WITH(NOLOCK) {1};SELECT @total;", sqls.TableName, where);
            sb.Append("IF(@total>0) BEGIN ");
            if (pageIndex == 1)
            {
                sb.AppendFormat("SELECT TOP ({0}) {1} FROM [{2}] WITH(NOLOCK) {3} {4}", pageSize, returnFields, sqls.TableName, where, orderBy);
            }
            else
            {
                sb.AppendFormat("WITH cte AS (SELECT ROW_NUMBER() OVER({0}) AS rownum,{1} FROM [{2}] WITH(NOLOCK) {3})", orderBy, returnFields, sqls.TableName, where);
                if (returnFields.Contains(" AS") || returnFields.Contains(" as"))
                {
                    sb.AppendFormat("SELECT * FROM cte WHERE cte.rownum BETWEEN {0} AND {1}", skip + 1, skip + pageSize);
                }
                else
                {
                    sb.AppendFormat("SELECT {0} FROM cte WHERE cte.rownum BETWEEN {1} AND {2}", returnFields, skip + 1, skip + pageSize);
                }
            }
            sb.Append(" END");

            using (var reader = conn.QueryMultiple(sb.ToString(), param, transaction, commandTimeout))
            {
                total = reader.ReadFirst<int>();
                if (total > 0)
                {
                    return reader.Read<T>();
                }
                else
                {
                    return new List<T>();
                }
            }

        }

        /// <summary>
        /// 获取分页数据
        /// </summary>
        public static IEnumerable<dynamic> GetByPageDynamic<T>(this IDbConnection conn, int pageIndex, int pageSize, out int total, string returnFields = null, string where = null, object param = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            if (returnFields == null)
                returnFields = sqls.AllFields;

            if (orderBy == null)
            {
                if (sqls.HasKey)
                {
                    orderBy = string.Format("ORDER BY [{0}] DESC", sqls.KeyName);
                }
                else
                {
                    orderBy = string.Format("ORDER BY [{0}]", sqls.AllFieldList.First());
                }
            }

            int skip = 0;
            if (pageIndex > 0)
            {
                skip = (pageIndex - 1) * pageSize;
            }

            StringBuilder sb = new StringBuilder();
            sb.AppendFormat("DECLARE @total INT;SELECT @total = COUNT(1) FROM [{0}] WITH(NOLOCK) {1};SELECT @total;", sqls.TableName, where);
            sb.Append("IF(@total>0) BEGIN ");
            if (pageIndex == 1)
            {
                sb.AppendFormat("SELECT TOP ({0}) {1} FROM [{2}] WITH(NOLOCK) {3} {4}", pageSize, returnFields, sqls.TableName, where, orderBy);
            }
            else
            {
                sb.AppendFormat("WITH cte AS (SELECT ROW_NUMBER() OVER({0}) AS rownum,{1} FROM [{2}] WITH(NOLOCK) {3})", orderBy, returnFields, sqls.TableName, where);
                if (returnFields.Contains(" AS") || returnFields.Contains(" as"))
                {
                    sb.AppendFormat("SELECT * FROM cte WHERE cte.rownum BETWEEN {0} AND {1}", skip + 1, skip + pageSize);
                }
                else
                {
                    sb.AppendFormat("SELECT {0} FROM cte WHERE cte.rownum BETWEEN {1} AND {2}", returnFields, skip + 1, skip + pageSize);
                }
            }
            sb.Append(" END");

            using (var reader = conn.QueryMultiple(sb.ToString(), param, transaction, commandTimeout))
            {
                total = reader.ReadFirst<int>();
                if (total > 0)
                {
                    return reader.Read();
                }
                else
                {
                    return new List<dynamic>();
                }
            }

        }

        /// <summary>
        /// 获取分页数据
        /// </summary>
        public static IEnumerable<T> GetByPage<T>(this IDbConnection conn, int pageIndex, int pageSize, out int total, string returnFields = null, string where = null, object param = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return GetByPageBase<T>(conn, typeof(T), pageIndex, pageSize, out total, returnFields, where, param, orderBy, transaction, commandTimeout);
        }

        /// <summary>
        /// 获取分页数据
        /// </summary>
        public static IEnumerable<T> GetByPage<Table, T>(this IDbConnection conn, int pageIndex, int pageSize, out int total, string returnFields = null, string where = null, object param = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return GetByPageBase<T>(conn, typeof(Table), pageIndex, pageSize, out total, returnFields, where, param, orderBy, transaction, commandTimeout);
        }

        /// <summary>
        /// 根据查询条件获取数据
        /// </summary>
        private static T GetByWhereFirstBase<T>(this IDbConnection conn, Type t, string where = null, object param = null, string returnFields = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(t);
            if (returnFields == null)
                returnFields = sqls.AllFields;
            string sql = string.Format("SELECT {0} FROM [{1}] WITH(NOLOCK) {2} {3}", returnFields, sqls.TableName, where, orderBy);

            return conn.QueryFirstOrDefault<T>(sql, param, transaction, commandTimeout);

        }

        /// <summary>
        /// 根据查询条件获取Dynamic数据
        /// </summary>
        public static dynamic GetByWhereFirstDynamic<T>(this IDbConnection conn, string where = null, object param = null, string returnFields = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            if (returnFields == null)
                returnFields = sqls.AllFields;
            string sql = string.Format("SELECT {0} FROM [{1}] WITH(NOLOCK) {2} {3}", returnFields, sqls.TableName, where, orderBy);

            return conn.QueryFirstOrDefault(sql, param, transaction, commandTimeout);
        }

        /// <summary>
        /// 根据查询条件获取数据
        /// </summary>
        public static T GetByWhereFirst<T>(this IDbConnection conn, string where = null, object param = null, string returnFields = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return GetByWhereFirstBase<T>(conn, typeof(T), where, param, returnFields, orderBy, transaction, commandTimeout);
        }

        /// <summary>
        /// 根据查询条件获取数据
        /// </summary>
        public static T GetByWhereFirst<Table, T>(this IDbConnection conn, string where = null, object param = null, string returnFields = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return GetByWhereFirstBase<T>(conn, typeof(Table), where, param, returnFields, orderBy, transaction, commandTimeout);
        }


        private static IEnumerable<T> GetByInBase<T>(this IDbConnection conn, Type t, string field, object ids, string returnFields = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            if (DapperExtCommon.ObjectIsEmpty(ids))
                return new List<T>();

            DapperExtSqls sqls = GetDapperExtSqls(t);
            DynamicParameters dpar = new DynamicParameters();

            dpar.Add("@ids", ids);
            if (returnFields == null)
                returnFields = sqls.AllFields;

            string sql = string.Format("SELECT {0} FROM [{1}] WITH(NOLOCK) WHERE [{2}] IN @ids", returnFields, sqls.TableName, field);
            return conn.Query<T>(sql, dpar, transaction, true, commandTimeout);
        }

        public static IEnumerable<dynamic> GetByInDynamic<T>(this IDbConnection conn, string field, object ids, string returnFields = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            if (DapperExtCommon.ObjectIsEmpty(ids))
                return new List<dynamic>();

            DapperExtSqls sqls = GetDapperExtSqls(typeof(T));
            DynamicParameters dpar = new DynamicParameters();

            dpar.Add("@ids", ids);
            if (returnFields == null)
                returnFields = sqls.AllFields;

            string sql = string.Format("SELECT {0} FROM [{1}] WITH(NOLOCK) WHERE [{2}] IN @ids", returnFields, sqls.TableName, field);
            return conn.Query(sql, dpar, transaction, true, commandTimeout);
        }

        public static IEnumerable<T> GetByIn<T>(this IDbConnection conn, string field, object ids, string returnFields = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return GetByInBase<T>(conn, typeof(T), field, ids, returnFields, transaction, commandTimeout);
        }

        public static IEnumerable<T> GetByIn<Table, T>(this IDbConnection conn, string field, object ids, string returnFields = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            return GetByInBase<T>(conn, typeof(Table), field, ids, returnFields, transaction, commandTimeout);
        }

        /// <summary>
        /// 获取分页数据 联合查询
        /// </summary>
        public static IEnumerable<T> GetByPageUnite<T>(this IDbConnection conn, string prefix, int pageIndex, int pageSize, out int total, string returnFields = null, string where = null, object param = null, string orderBy = null, IDbTransaction transaction = null, int? commandTimeout = null)
        {
            StringBuilder sb = new StringBuilder();
            sb.AppendFormat("SELECT COUNT(1) FROM {0};", where);
            sb.AppendFormat("select top {3} * from(select row_number() over(order by {4}CreateTime desc) as rownumber,{0} from {1}) temp_table where rownumber > (({2}-1)*{3})", returnFields, where, pageIndex, pageSize, prefix);
            using (var reader = conn.QueryMultiple(sb.ToString(), param, transaction, commandTimeout))
            {
                total = reader.ReadFirst<int>();
                return reader.Read<T>();
            }
        }
    }
}