/*
|-------------------------------------------------------------------------------|
|	Copyright © Computer Ease Limited								            |
|	Address: 1/9 Bloack-A Lalmatia, Dhaka-1207, Bangladesh			            |
|	Email: info@celimited.com, cease@bol-online.com, web: www.celimited.com     |
|	Unauthorized copy or distribution is strictly prohibited		            |
|	Author: S. M. Russel,  Last modified date: 17/04/2009						|
|-------------------------------------------------------------------------------|
*/

using System;
using System.Data;
using System.Data.OracleClient;
using Ease.Core.DataAccess;
using Ease.Core.Utility;

namespace Ease.CoreV35.DataAccess.Oracle
{
    #region DataAccess: Oracle Helper

    public sealed class OracleHelperExtension
    {
        private OracleHelperExtension()
        {
        }

        #region Fill Data set

        /// <summary>
        /// Fills a typed DataSet using the DataReader's current result. This method 
        /// allows paginated access to the database.
        /// </summary>
        /// <param name="dataReader">The DataReader used to fetch the values.</param>
        /// <param name="dataSet">The DataSet used to store the values.</param>
        /// <param name="tableName">The name of the DataSet table used to add the 
        /// DataReader records.</param>
        /// <param name="from">The quantity of records skipped before placing
        /// values on the DataReader on the DataSet.</param>
        /// <param name="count">The maximum quantity of records alloed to fill on the
        /// DataSet.</param>
        public static void Fill(IDataReader dataReader, DataSet dataSet, string tableName, int from, int count)
        {
            DataAccessHelper.Fill(dataReader, dataSet, tableName, from, count);
        }

        /// <summary>
        /// Fills a typed DataSet using the DataReader's current result. This method 
        /// allows paginated access to the database.
        /// </summary>
        /// <param name="dataReader">The DataReader used to fetch the values.</param>
        /// <param name="dataSet">The DataSet used to store the values.</param>
        /// <param name="tableName">The name of the DataSet table used to add the DataReader records.</param>
        public static void Fill(IDataReader dataReader, DataSet dataSet, string tableName)
        {
            OracleHelperExtension.Fill(dataReader, dataSet, tableName, 0, 0);
        }

        #endregion

        #region Parameter

        /// <summary>
        /// Return OracleParameter object according to parameter.
        /// </summary>
        /// <param name="pType">Type of data.</param>
        /// <param name="direction">Direction of parameter.</direction>
        /// <param name="pValue">Value of parametetr.</param>
        /// <returns>Instatnce of OracleParameter.</returns>
        public static OracleParameter CreateParam(OracleType pType, ParameterDirection direction, object pValue)
        {
            return OracleHelperExtension.CreateParam(string.Empty, pType, direction, pValue);
        }

        /// <summary>
        /// Return OracleParameter object according to parameter.
        /// </summary>
        /// <param name="pName">Name of parameter.</param>
        /// <param name="pType">Type of data.</param>
        /// <param name="direction">Direction of parameter.</param>
        /// <returns>Instatnce of OracleParameter.</returns>
        public static OracleParameter CreateParam(string pName, OracleType pType, ParameterDirection direction)
        {
            return OracleHelperExtension.CreateParam(pName, pType, direction, null);
        }

        /// <summary>
        /// Return OracleParameter object according to parameter.
        /// </summary>
        /// <param name="pName">Name of parameter.</param>
        /// <param name="pType">Type of data.</param>
        /// <param name="direction">Direction of parameter.</direction>
        /// <param name="pValue">Value of parametetr.</param>
        /// <returns>Instatnce of OracleParameter.</returns>
        public static OracleParameter CreateParam(string pName, OracleType pType, ParameterDirection direction,
            object pValue)
        {
            OracleParameter param = new OracleParameter(pName, pType);
            param.Direction = direction;
            if (pType == OracleType.VarChar)
                param.Size = 1000;
            param.Value = pValue;

            return param;
        }

        /// <summary>
        /// Return OracleParameter object according to parameter.
        /// </summary>
        /// <param name="pName">Name of parameter.</param>
        /// <param name="pType">Type of data.</param>
        /// <param name="direction">Direction of parameter.</param>
        /// <param name="pValue">Value of parametetr.</param>
        /// <param name="size">If varchar then lenth of value.</param>
        /// <returns>Instatnce of OracleParameter.</returns>
        public static OracleParameter CreateParam(string pName, OracleType pType, ParameterDirection direction,
            int size, object pValue)
        {
            OracleParameter param = new OracleParameter(pName, pType);
            param.Direction = direction;
            param.Size = size;
            param.Value = pValue;

            return param;
        }

        #endregion

        #region Input Parameter

        /// <summary>
        /// Return input direction OracleParameter object.
        /// </summary>
        /// <param name="pType">Type of data.</param>
        /// <param name="pValue">Value of parametetr.</param>
        /// <returns>Instatnce of OracleParameter.</returns>
        public static OracleParameter CreateInParam(OracleType pType, object pValue)
        {
            return OracleHelperExtension.CreateInParam(string.Empty, pType, pValue);
        }


        /// <summary>
        /// Return input direction OracleParameter object.
        /// </summary>
        /// <param name="pName">Name of parameter.</param>
        /// <param name="pType">Type of data.</param>
        /// <returns>Instatnce of OracleParameter.</returns>
        public static OracleParameter CreateInParam(string pName, OracleType pType)
        {
            return OracleHelperExtension.CreateInParam(pName, pType, null);
        }

        /// <summary>
        /// Return input direction OracleParameter object.
        /// </summary>
        /// <param name="pName">Name of parameter.</param>
        /// <param name="pType">Type of data.</param>
        /// <param name="pValue">Value of parametetr.</param>
        /// <returns>Instatnce of OracleParameter.</returns>
        public static OracleParameter CreateInParam(string pName, OracleType pType, object pValue)
        {
            OracleParameter param = new OracleParameter(pName, pType);
            param.Direction = ParameterDirection.Input;
            if (pType == OracleType.VarChar)
                param.Size = 1000;
            param.Value = pValue;

            return param;
        }

        /// <summary>
        /// Return input direction OracleParameter object.
        /// </summary>
        /// <param name="pName">Name of parameter.</param>
        /// <param name="pType">Type of data.</param>
        /// <param name="pValue">Value of parametetr.</param>
        /// <param name="size">If varchar then lenth of value.</param>
        /// <returns>Instatnce of OracleParameter.</returns>
        public static OracleParameter CreateInParam(string pName, OracleType pType, object pValue, int size)
        {
            OracleParameter param = new OracleParameter(pName, pType);
            param.Direction = ParameterDirection.Input;
            param.Size = size;
            param.Value = pValue;

            return param;
        }

        #endregion

        #region Output Parameter

        /// <summary>
        /// Return output direction OracleParameter object.
        /// </summary>
        /// <param name="pType">Type of data.</param>
        /// <param name="pValue">Value of parametetr.</param>
        /// <returns>Instatnce of OracleParameter.</returns>
        public static OracleParameter CreateOutParam(OracleType pType, object pValue)
        {
            return OracleHelperExtension.CreateOutParam(string.Empty, pType, pValue);
        }

        /// <summary>
        /// Return output direction OracleParameter object.
        /// </summary>
        /// <param name="pName">Name of parameter.</param>
        /// <param name="pType">Type of data.</param>
        /// <returns>Instatnce of OracleParameter.</returns>
        public static OracleParameter CreateOutParam(string pName, OracleType pType)
        {
            return OracleHelperExtension.CreateOutParam(pName, pType, null);
        }

        /// <summary>
        /// Return output direction OracleParameter object.
        /// </summary>
        /// <param name="pName">Name of parameter.</param>
        /// <param name="pType">Type of data.</param>
        /// <param name="pValue">Value of parametetr.</param>
        /// <returns>Instatnce of OracleParameter.</returns>
        public static OracleParameter CreateOutParam(string pName, OracleType pType, object pValue)
        {
            OracleParameter param = new OracleParameter(pName, pType);
            param.Direction = ParameterDirection.Output;
            if (pType == OracleType.VarChar)
            {
                param.Size = 1000;
            }

            param.Value = pValue;

            return param;
        }

        /// <summary>
        /// Return output direction OracleParameter object.
        /// </summary>
        /// <param name="pName">Name of parameter.</param>
        /// <param name="pType">Type of data.</param>
        /// <param name="pValue">Value of parametetr.</param>
        /// <param name="size">If varchar then lenth of value.</param>
        /// <returns>Instatnce of OracleParameter.</returns>
        public static OracleParameter CreateOutParam(string pName, OracleType pType, object pValue, int size)
        {
            OracleParameter param = new OracleParameter(pName, pType);
            param.Direction = ParameterDirection.Output;
            param.Size = size;
            param.Value = pValue;

            return param;
        }

        #endregion

        #region Add Parameter

        public static OracleCommand CreateCommand(string name)
        {
            OracleCommand command = new OracleCommand(name);

            return command;
        }

        public static void AddParameter(OracleCommand command, string name, OracleType type,
            ParameterDirection direction, object Value)
        {
            OracleParameter param = command.CreateParameter();

            param.ParameterName = name;
            param.OracleType = type;
            param.Direction = direction;
            if (type == OracleType.VarChar)
                param.Size = 4000;
            param.Value = Value;
            command.Parameters.Add(param);
        }

        public static void AddParameter(OracleCommand command, string name, OracleType type,
            ParameterDirection direction)
        {
            OracleHelperExtension.AddParameter(command, name, type, direction, null);
        }

        #endregion

        #region GetBlob

        public static OracleLob GetBlob(TransactionContext tc, byte[] bytes)
        {
            OracleLob tblob = GetTempBlob(tc);
            tblob.BeginBatch(OracleLobOpenMode.ReadWrite);
            tblob.Write(bytes, 0, bytes.Length);
            tblob.EndBatch();

            return tblob;
        }

        public static OracleLob GetTempBlob(TransactionContext tc)
        {
            OracleCommand command =
                new OracleCommand("DECLARE t BLOB; BEGIN DBMS_LOB.CREATETEMPORARY(t, false, 0); :tempblob := t; END;");
            AddParameter(command, "tempblob", OracleType.Blob, ParameterDirection.Output);

            tc.PrepareCommand(command);
            command.ExecuteNonQuery();

            return (OracleLob) (command.Parameters[0]).Value;
        }

        #endregion

        #region private function

        private static object GetValue(object fieldValue, Type fieldType)
        {
            switch (fieldType.Name)
            {
                case "Int16":
                case "Int32":
                case "Int64":
                    if (fieldValue == DBNull.Value)
                        return 0;
                    else
                        return fieldValue;
            }

            return fieldValue;
        }

        #endregion
    }

    #endregion
}