using System;
using System.Data;

namespace EntityMapping
{
	/// <summary>
	/// DataAccessObject 的摘要說明。
	/// </summary>
	public class DataAccessObject
	{
		private EntityMapping.DataType m_dbType;
		private System.Data.IDbDataAdapter m_DataAp;
		private System.Data.IDbConnection m_DBCon;
		private System.Data.IDbCommand m_DBCom;
		private System.Data.DataSet m_Ds = new DataSet();

		private string m_str_Con ;


		public EntityMapping.DataType DBType
		{
			get 
			{
				return this.m_dbType;
			}
		}
		/// <summary>
		/// 設置數據類別
		/// </summary>
		/// <param name="dbType">數據庫的類別</param>
		public DataAccessObject(DataType dbType)
		{
			this.m_dbType = dbType;
			if(this.m_dbType == DataType.Oracle)
			{
				
			}
			//if(this.m_dbType = )
			//
			// TODO: 在此處添加構造函數邏輯
			//
		}

		/// <summary>
		/// 設置數據訪問對象的數據庫類別以及鏈接字符串
		/// </summary>
		/// <param name="dbType"></param>
		/// <param name="str_Con"></param>
		public DataAccessObject(DataType dbType,string str_Con)
		{
			this.m_str_Con = str_Con;
			this.m_dbType = dbType;
			EntityMapping.IDataAccess dataAccess = new OracleFactory();
			if(this.m_dbType == DataType.Oracle)
			{
				dataAccess = new OracleFactory();
			}
			this.m_DBCon = dataAccess.GetConnection();
			this.m_DBCon.ConnectionString = str_Con;
			this.m_DBCom = dataAccess.GetCommand();
			this.m_DataAp = dataAccess.GetDataAdapter();

		}
		
		/// <summary>
		/// 執行ＳＱＬ語句
		/// </summary>
		/// <param name="Sql">要執行的ＳＱＬ語句</param>
		/// <returns>返回受影響記錄的條數</returns>
		public int ExcuteBySql(string Sql)
		{
			try
			{
				if(this.m_DBCon.State == System.Data.ConnectionState.Closed)
				{
					this.m_DBCon.Open();
				}
				this.m_DBCom.Connection = this.m_DBCon;
				this.m_DBCom.CommandText = Sql;
				int i = this.m_DBCom.ExecuteNonQuery();
				if(this.m_DBCon.State == System.Data.ConnectionState.Open)
				{
					this.m_DBCon.Close();
				}
				return i;
			}
			catch(Exception exp)
			{
				throw new Exception(exp.ToString());
				this.m_DBCon.Close();
			}
		}

		/// <summary>
		/// 打開一個鏈接對象
		/// </summary>
		/// <returns>返回鏈接對象的當前狀態</returns>
		public string Open()
		{
			try
			{
				this.m_DBCon.ConnectionString = this.m_str_Con;
				this.m_DBCon.Open();
				return this.m_DBCon.State.ToString();

			}
			catch
			{
				return this.m_DBCon.State.ToString();
	
			}
		}

		/// <summary>
		/// 關閉鏈接對象
		/// </summary>
		/// <returns>返回鏈接對象的當前狀態</returns>
		public string Close()
		{
			try
			{
				this.m_DBCon.Close();
				return this.m_DBCon.State.ToString();
			}
			catch
			{
				return this.m_DBCon.State.ToString();
			}

		}

		/// <summary>
		/// 根據ＳＱＬ語句查詢數據
		/// </summary>
		/// <param name="Sql">ＳＱＬ查詢語句</param>
		/// <returns>返回包含查詢結果的數據集對象</returns>
		public DataSet QueryBySql(string Sql)
		{
			if(this.m_DBCon.State == System.Data.ConnectionState.Closed)
			{
				this.m_DBCon.Open();
			}
			this.m_DBCom.Connection = this.m_DBCon;
			this.m_DBCom.CommandText = Sql;
			//System.Data.SqlClient.SqlDataAdapter s = new System.Data.SqlClient.SqlDataAdapter();
			
			this.m_DataAp.SelectCommand = this.m_DBCom;
			this.m_DataAp.Fill(this.m_Ds);
			this.m_DBCon.Close();
			return this.m_Ds;
		}

		 ~DataAccessObject()
		{
			if(this.m_DBCon.State == System.Data.ConnectionState.Open)
			{
				this.m_DBCon.Close();
			}
		}
	}
}