using System;
using System.Collections.Generic;
using System.Data;
using System.IO;
using System.Text;
using System.Xml;
using System.Xml.Serialization;
using System.Data.Common;
using Mesnac.Equips;
using Mesnac.Maths;

namespace Mesnac.Math.Database
{
    public class ExecuteSql : IMath
    {
        private object NullResult = new DataTable();

        public string Name
        {
            get { return "执行语句"; }
        }

        public string Caption
        {
            get
            {
                StringBuilder sb = new StringBuilder();
                sb.AppendLine("必须填写使用数据库连接的设备名称");
                sb.AppendLine("例：");
                sb.Append("    ").Append(Name).AppendLine("(A1)");
                return sb.ToString();
            }
        }

        public object Execute(string[] parameters, object[] buff)
        {
            string sqlstr = string.Empty;
            if ((buff.Length > 0)
                && (buff[0] != null)
                && (!string.IsNullOrWhiteSpace(buff[0].ToString())))
            {
                sqlstr = buff[0].ToString();
            }
            if (string.IsNullOrWhiteSpace(sqlstr))
            {
                return this.NullResult;
            }
            if (parameters.Length < 1)
            {
                return this.NullResult;
            }
            string equipName = parameters[0];
            BaseEquip equip = null;
            if (!Mesnac.Equips.Factory.Instance.AllEquips.TryGetValue(equipName, out equip))
            {
                return this.NullResult;
            }
            DbConnection conn = equip.Main.ConnType.Connection as DbConnection;
            if (conn == null)
            {
                return this.NullResult;
            }
            bool isOpen = true;
            if (conn.State != ConnectionState.Open)
            {
                isOpen = false;
                conn.Open();
            }


            DataTable Result = new DataTable();
            DbCommand sqlcmd = conn.CreateCommand();
            try
            {
                sqlcmd.CommandType = System.Data.CommandType.Text;
                sqlcmd.CommandText = sqlstr;
                Result.Load(sqlcmd.ExecuteReader());
                if (!isOpen)
                {
                    conn.Close();
                }
            }
            catch
            {
            }
            Result.TableName = sqlstr;
            return Result;
        }
    }


    public class ExecuteSqlXmlToTable : IMath
    {
        private object NullResult = new DataTable();

        public string Name
        {
            get { return "执行SQL反序列化"; }
        }

        public string Caption
        {
            get
            {
                StringBuilder sb = new StringBuilder();
                sb.AppendLine("必须填写使用数据库连接的设备名称");
                sb.AppendLine("例：");
                sb.Append("    ").Append(Name).AppendLine("(A1)");
                return sb.ToString();
            }
        }

        public object Execute(string[] parameters, object[] buff)
        {
            string sqlstr = string.Empty;
            if ((buff.Length > 0)
                && (buff[0] != null)
                && (!string.IsNullOrWhiteSpace(buff[0].ToString())))
            {
                sqlstr = buff[0].ToString();
            }
            if (string.IsNullOrWhiteSpace(sqlstr))
            {
                return this.NullResult;
            }
            if (parameters.Length < 1)
            {
                return this.NullResult;
            }
            string equipName = parameters[0];
            BaseEquip equip = null;
            if (!Mesnac.Equips.Factory.Instance.AllEquips.TryGetValue(equipName, out equip))
            {
                return this.NullResult;
            }
            DbConnection conn = equip.Main.ConnType.Connection as DbConnection;
            if (conn == null)
            {
                return this.NullResult;
            }
            
            bool isOpen = true;
            if (conn.State != ConnectionState.Open)
            {
                isOpen = false;
                conn.Open();
            }

            DataTable Result = new DataTable();
            DbCommand sqlcmd = conn.CreateCommand();
            try
            {
                sqlcmd.CommandType = System.Data.CommandType.Text;
                sqlcmd.CommandText = sqlstr;
                object obj = sqlcmd.ExecuteScalar();
                string xml = string.Empty;
                if (obj != null && obj != DBNull.Value)
                {
                    xml = obj.ToString();
                }
                if (!isOpen)
                {
                    conn.Close();
                }
                if (string.IsNullOrWhiteSpace(xml))
                {
                    return this.NullResult;
                }
                Result = DeserializeDataTable(xml);
            }
            catch
            {
            }
            Result.TableName = sqlstr;
            return Result;
        }

        private DataTable DeserializeDataTable(string pXml)
        {
            StringReader strReader = new StringReader(pXml);
            XmlReader xmlReader = XmlReader.Create(strReader);
            XmlSerializer serializer = new XmlSerializer(typeof(DataTable));
            DataTable dt = serializer.Deserialize(xmlReader) as DataTable;
            return dt;
        } 
    }


}