using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.SqlClient;
using System.Collections;
using System.Data;
using System.Windows.Forms;
namespace CRVM.Utility
{
    class SqlDBUtility
    {
        private static SqlDBUtility dbInstance = null;
        //public static string sqlConnectionString = "Data Source=FAC1CAL;Persist Security Info=True;User ID=prdb;Password=prdb;Unicode=True";
       //sqlConnStr = "server = localhost;  user id = sa; password = xxx; database = northwind"
        public static string sqlConnectionString ="";

        private Hashtable parmCache = Hashtable.Synchronized(new Hashtable());


        private SqlDBUtility()
        {
            sqlConnectionString = SettingConnectionString();
        }

       /// <summary>
       /// singleton
       /// </summary>
        public static SqlDBUtility Instance
       {
           get
           {
               if (dbInstance == null)
                   dbInstance = new SqlDBUtility();
               return dbInstance;
           }
       }

       /// <summary>
       /// Make connection string for open database
       /// </summary>
       /// <returns>connection string</returns>
       private string SettingConnectionString()
       {
           //string path = Application.StartupPath + "\\app\\form\\hmisetting.xml";
           string dataconn = "";
           //const string dataConf = "数据库配置";
           //EntityConfigItem database = ConfigHelper.GetInstance(path).GetConfigItemData(dataConf, "database");
           //EntityConfigItem userid = ConfigHelper.GetInstance(path).GetConfigItemData(dataConf, "userid");
           //EntityConfigItem password = ConfigHelper.GetInstance(path).GetConfigItemData(dataConf, "password");
           //EntityConfigItem ip = ConfigHelper.GetInstance(path).GetConfigItemData(dataConf, "ip");
           //dataconn = "server = " + ip.Values + ";User ID=" + userid.Values + ";Password=" + password.Values + ";database=" + database.Values;
           return dataconn;
       }


        /// <summary>
        /// Execute a database query which does not include a select
        /// </summary>
        /// <param name="connString">Connection string to database</param>
        /// <param name="cmdType">Command type either stored procedure or SQL</param>
        /// <param name="cmdText">Acutall SQL Command</param>
        /// <param name="commandParameters">Parameters to bind to the command</param>
        /// <returns></returns>
       public int ExecuteNonQuery(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)
       {
           // Create a new Sql command
           SqlCommand cmd = new SqlCommand();

           //Create a connection
           using (SqlConnection connection = new SqlConnection(connectionString))
           {

               //Prepare the command
               PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);

               //Execute the command
               int val = cmd.ExecuteNonQuery();
               cmd.Parameters.Clear();
               try
               {
                   connection.Close();
               }
               catch
               { }
               return val;
           }
       }

        /// <summary>
        /// Execute an SqlCommand (that returns no resultset) against an existing database transaction 
        /// using the provided parameters.
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "PublishOrders", new SqlParameter(":prodid", 24));
        /// </remarks>
        /// <param name="trans">an existing database transaction</param>
        /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
        /// <param name="commandText">the stored procedure name or PL/SQL command</param>
        /// <param name="commandParameters">an array of SqlParamters used to execute the command</param>
        /// <returns>an int representing the number of rows affected by the command</returns>
       public int ExecuteNonQuery(SqlTransaction trans, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)
       {
           SqlCommand cmd = new SqlCommand();
           PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, commandParameters);
           int val = cmd.ExecuteNonQuery();
           cmd.Parameters.Clear();
           return val;
       }

        /// <summary>
        /// Execute an SqlCommand (that returns no resultset) against an existing database connection 
        /// using the provided parameters.
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter(":prodid", 24));
        /// </remarks>
        /// <param name="conn">an existing database connection</param>
        /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
        /// <param name="commandText">the stored procedure name or PL/SQL command</param>
        /// <param name="commandParameters">an array of SqlParamters used to execute the command</param>
        /// <returns>an int representing the number of rows affected by the command</returns>
       public int ExecuteNonQuery(SqlConnection connection, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)
       {
           try
           {
               SqlCommand cmd = new SqlCommand();

               PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);
               int val = cmd.ExecuteNonQuery();
               cmd.Parameters.Clear();
               return val;
           }
           catch
           {
               throw;
           }
           finally
           {
               connection.Close();
           }
       }

        /// <summary>
        /// Execute a select query that will return a result set
        /// </summary>
        /// <param name="connString">Connection string</param>
        //// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
        /// <param name="commandText">the stored procedure name or PL/SQL command</param>
        /// <param name="commandParameters">an array of SqlParamters used to execute the command</param>
        /// <returns></returns>
       public SqlDataReader ExecuteReader(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)
       {
           //if (oraconn.State != ConnectionState.Open)
           //{
           //    oraconn.Open();
           //}
           //Create the command and connection
           SqlCommand cmd = new SqlCommand();
           SqlConnection conn = new SqlConnection(connectionString);

           try
           {
               //Prepare the command to execute
               PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);
               // PrepareCommand(cmd, oraconn, null, cmdType, cmdText, commandParameters);
               //Execute the query, stating that the connection should close when the resulting datareader has been read
               SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
               //SqlDataReader rdr = cmd.ExecuteReader(); //xcs,2009-07-27
               cmd.Parameters.Clear();
               return rdr;

           }
           catch
           {
               conn.Close();

               //If an error occurs close the connection as the reader will not be used and we expect it to close the connection
               throw;
           }

       }

       /// <summary>
        /// Execute an SqlCommand that returns the first column of the first record against the database specified in the connection string 
        /// using the provided parameters.
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  Object obj = ExecuteScalar(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter(":prodid", 24));
        /// </remarks>
        /// <param name="connectionString">a valid connection string for a SqlConnection</param>
        /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
        /// <param name="commandText">the stored procedure name or PL/SQL command</param>
        /// <param name="commandParameters">an array of SqlParamters used to execute the command</param>
        /// <returns>An object that should be converted to the expected type using Convert.To{Type}</returns>
       public object ExecuteScalar(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)
       {
           SqlCommand cmd = new SqlCommand();

           using (SqlConnection conn = new SqlConnection(connectionString))
           {
               PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);
               object val = cmd.ExecuteScalar();
               cmd.Parameters.Clear();
               return val;
           }
       }

       ///	<summary>
        ///	Execute	a SqlCommand (that returns a 1x1 resultset)	against	the	specified SqlTransaction
        ///	using the provided parameters.
        ///	</summary>
        ///	<param name="transaction">A	valid SqlTransaction</param>
        ///	<param name="commandType">The CommandType (stored procedure, text, etc.)</param>
        ///	<param name="commandText">The stored procedure name	or PL/SQL command</param>
        ///	<param name="commandParameters">An array of	SqlParamters used to execute the command</param>
        ///	<returns>An	object containing the value	in the 1x1 resultset generated by the command</returns>
       public object ExecuteScalar(SqlTransaction transaction, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
       {
           if (transaction == null)
               throw new ArgumentNullException("transaction");
           if (transaction != null && transaction.Connection == null)
               throw new ArgumentException("The transaction was rollbacked	or commited, please	provide	an open	transaction.", "transaction");

           // Create a	command	and	prepare	it for execution
           SqlCommand cmd = new SqlCommand();

           PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters);

           // Execute the command & return	the	results
           object retval = cmd.ExecuteScalar();

           // Detach the SqlParameters	from the command object, so	they can be	used again
           cmd.Parameters.Clear();
           return retval;
       }

       /// <summary>
        /// Execute an SqlCommand that returns the first column of the first record against an existing database connection 
        /// using the provided parameters.
        /// </summary>
        /// <remarks>
        /// e.g.:  
        ///  Object obj = ExecuteScalar(conn, CommandType.StoredProcedure, "PublishOrders", new SqlParameter(":prodid", 24));
        /// </remarks>
        /// <param name="conn">an existing database connection</param>
        /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
        /// <param name="commandText">the stored procedure name or PL/SQL command</param>
        /// <param name="commandParameters">an array of SqlParamters used to execute the command</param>
        /// <returns>An object that should be converted to the expected type using Convert.To{Type}</returns>
       public object ExecuteScalar(SqlConnection connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)
       {
           try
           {
               SqlCommand cmd = new SqlCommand();

               PrepareCommand(cmd, connectionString, null, cmdType, cmdText, commandParameters);
               object val = cmd.ExecuteScalar();
               cmd.Parameters.Clear();
               return val;
           }
           catch
           {
               //If an error occurs close the connection as the reader will not be used and we expect it to close the connection
               throw;
           }
           finally
           {
               connectionString.Close();

           }
       }

       /// <summary>
        /// Add a set of parameters to the cached
        /// </summary>
        /// <param name="cacheKey">Key value to look up the parameters</param>
        /// <param name="commandParameters">Actual parameters to cached</param>
       public void CacheParameters(string cacheKey, params SqlParameter[] commandParameters)
       {
           parmCache[cacheKey] = commandParameters;
       }

        /// <summary>
        /// Fetch parameters from the cache
        /// </summary>
        /// <param name="cacheKey">Key to look up the parameters</param>
        /// <returns></returns>
       public SqlParameter[] GetCachedParameters(string cacheKey)
       {
           SqlParameter[] cachedParms = (SqlParameter[])parmCache[cacheKey];

           if (cachedParms == null)
               return null;

           // If the parameters are in the cache
           SqlParameter[] clonedParms = new SqlParameter[cachedParms.Length];

           // return a copy of the parameters
           for (int i = 0, j = cachedParms.Length; i < j; i++)
               clonedParms[i] = (SqlParameter)((ICloneable)cachedParms[i]).Clone();

           return clonedParms;
       }

        /// <summary>
        /// Internal function to prepare a command for execution by the database
        /// </summary>
        /// <param name="cmd">Existing command object</param>
        /// <param name="conn">Database connection object</param>
        /// <param name="trans">Optional transaction object</param>
        /// <param name="cmdType">Command type, e.g. stored procedure</param>
        /// <param name="cmdText">Command test</param>
        /// <param name="commandParameters">Parameters for the command</param>
       private void PrepareCommand(SqlCommand cmd, SqlConnection conn, SqlTransaction trans, CommandType cmdType, string cmdText, SqlParameter[] commandParameters)
       {

           //Open the connection if required
           if (conn.State != ConnectionState.Open)
               conn.Open();

           //Set up the command
           cmd.Connection = conn;
           cmd.CommandText = cmdText;
           cmd.CommandType = cmdType;

           //Bind it to the transaction if it exists
           if (trans != null)
               cmd.Transaction = trans;

           // Bind the parameters passed in
           if (commandParameters != null)
           {
               foreach (SqlParameter parm in commandParameters)
                   cmd.Parameters.Add(parm);
           }
       }


       /// <summary>
        /// Converter to use boolean data type with Sql
        /// </summary>
        /// <param name="value">Value to convert</param>
        /// <returns></returns>
        public  string OraBit(bool value)
        {
            if (value)
                return "Y";
            else
                return "N";
        }

        /// <summary>
        /// Converter to use boolean data type with Sql
        /// </summary>
        /// <param name="value">Value to convert</param>
        /// <returns></returns>
        public  bool OraBool(string value)
        {
            if (value.Equals("Y"))
                return true;
            else
                return false;
        }


    }
}