namespace SqlSugar
{
    public class SqlServerDbMaintenance : DbMaintenanceProvider
    {
        #region DML
        protected override string GetColumnInfosByTableNameSql
        {
            get
            {
                var sql = @"SELECT sysobjects.name AS TableName,
                           syscolumns.Id AS TableId,
                           syscolumns.name AS DbColumnName,
                           systypes.name AS DataType,
                           syscolumns.length AS [Length],
                           sys.extended_properties.[value] AS [ColumnDescription],
                           syscomments.text AS DefaultValue,
                           syscolumns.isnullable AS IsNullable,
	                       columnproperty(syscolumns.id,syscolumns.name,'IsIdentity')as IsIdentity,
                           (CASE
                                WHEN EXISTS
                                       ( 
                                             	select 1
												from sysindexes i
												join sysindexkeys k on i.id = k.id and i.indid = k.indid
												join sysobjects o on i.id = o.id
												join syscolumns c on i.id=c.id and k.colid = c.colid
												where o.xtype = 'U' 
												and exists(select 1 from sysobjects where xtype = 'PK' and name = i.name) 
												and o.name=sysobjects.name and c.name=syscolumns.name
                                       ) THEN 1
                                ELSE 0
                            END) AS IsPrimaryKey
                    FROM syscolumns
                    INNER JOIN systypes ON syscolumns.xtype = systypes.xtype
                    LEFT JOIN sysobjects ON syscolumns.id = sysobjects.id
                    LEFT OUTER JOIN sys.extended_properties ON (sys.extended_properties.minor_id = syscolumns.colid
                                                                AND sys.extended_properties.major_id = syscolumns.id)
                    LEFT OUTER JOIN syscomments ON syscolumns.cdefault = syscomments.id
                    WHERE syscolumns.id IN
                        (SELECT id
                         FROM sysobjects
                         WHERE xtype IN('u',
                                        'v') )
                      AND (systypes.name <> 'sysname')
                      AND sysobjects.name='{0}'
                      AND systypes.name<>'geometry'
                      AND systypes.name<>'geography'
                    ORDER BY syscolumns.colid";
                return sql;
            }
        }
        protected override string GetTableInfoListSql
        {
            get
            {
                return @"SELECT s.Name,Convert(varchar(max),tbp.value) as Description
                            FROM sysobjects s
					     	LEFT JOIN sys.extended_properties as tbp ON s.id=tbp.major_id and tbp.minor_id=0 AND (tbp.Name='MS_Description' OR tbp.Name is null)  WHERE s.xtype IN('U') ";
            }
        }
        protected override string GetViewInfoListSql
        {
            get
            {
                return @"SELECT s.Name,Convert(varchar(max),tbp.value) as Description
                            FROM sysobjects s
					     	LEFT JOIN sys.extended_properties as tbp ON s.id=tbp.major_id and tbp.minor_id=0  AND (tbp.Name='MS_Description' OR tbp.Name is null) WHERE s.xtype IN('V')  ";
            }
        }
        #endregion

        #region DDL
        protected override string AddPrimaryKeySql
        {
            get
            {
                return "ALTER TABLE {0} ADD CONSTRAINT {1} PRIMARY KEY({2})";
            }
        }
        protected override string AddColumnToTableSql
        {
            get
            {
                return "ALTER TABLE {0} ADD {1} {2}{3} {4} {5} {6}";
            }
        }
        protected override string AlterColumnToTableSql
        {
            get
            {
                return "ALTER TABLE {0} ALTER COLUMN {1} {2}{3} {4} {5} {6}";
            }
        }
        protected override string BackupDataBaseSql
        {
            get
            {
                return @"USE master;BACKUP DATABASE {0} TO disk = '{1}'";
            }
        }
        protected override string CreateTableSql
        {
            get
            {
                return "CREATE TABLE {0}(\r\n{1})";
            }
        }
        protected override string CreateTableColumn
        {
            get
            {
                return "{0} {1}{2} {3} {4} {5}";
            }
        }
        protected override string TruncateTableSql
        {
            get
            {
                return "TRUNCATE TABLE {0}";
            }
        }
        protected override string BackupTableSql
        {
            get
            {
                return "SELECT TOP {0} *　INTO {1} FROM  {2}";
            }
        }
        protected override string DropTableSql
        {
            get
            {
                return "DROP TABLE {0}";
            }
        }
        protected override string DropColumnToTableSql
        {
            get
            {
                return "ALTER TABLE {0} DROP COLUMN {1}";
            }
        }
        protected override string DropConstraintSql
        {
            get
            {
                return "ALTER TABLE {0} DROP CONSTRAINT  {1}";
            }
        }
        protected override string RenameColumnSql
        {
            get
            {
                return "exec sp_rename '{0}.{1}','{2}','column';";
            }
        }
        #endregion

        #region Check
        protected override string CheckSystemTablePermissionsSql
        {
            get
            {
                return "select top 1 id from sysobjects";
            }
        }
        #endregion

        #region Scattered
        protected override string CreateTableNull
        {
            get
            {
                return "NULL";
            }
        }
        protected override string CreateTableNotNull
        {
            get
            {
                return "NOT NULL";
            }
        }
        protected override string CreateTablePirmaryKey
        {
            get
            {
                return "PRIMARY KEY";
            }
        }
        protected override string CreateTableIdentity
        {
            get
            {
                return "IDENTITY(1,1)";
            }
        }
        #endregion
    }
}