// Copyright ?2004, 2014, Oracle and/or its affiliates. All rights reserved.
//
// MySQL Connector/NET is licensed under the terms of the GPLv2
// <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>, like most 
// MySQL Connectors. There are special exceptions to the terms and 
// conditions of the GPLv2 as it is applied to this software, see the 
// FLOSS License Exception
// <http://www.mysql.com/about/legal/licensing/foss-exception.html>.
//
// This program is free software; you can redistribute it and/or modify 
// it under the terms of the GNU General Public License as published 
// by the Free Software Foundation; version 2 of the License.
//
// This program is distributed in the hope that it will be useful, but 
// WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
// or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 
// for more details.
//
// You should have received a copy of the GNU General Public License along 
// with this program; if not, write to the Free Software Foundation, Inc., 
// 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA

#if MYSQL_6_9

using System;
using System.Data;
using System.Data.Common;
using System.ComponentModel;
using System.Collections.Generic;
#if MYSQL_6_9
using System.Threading.Tasks;
using System.Threading;
#endif

namespace Externals.MySql.Data.MySqlClient
{
  [System.Drawing.ToolboxBitmap(typeof(MySqlDataAdapter), "MySqlClient.resources.dataadapter.bmp")]
  [System.ComponentModel.DesignerCategory("Code")]
  [Designer("Externals.MySql.Data.MySqlClient.Design.MySqlDataAdapterDesigner,MySqlClient.Design")]
  internal sealed class MySqlDataAdapter : DbDataAdapter, IDbDataAdapter, IDataAdapter, ICloneable
  {
    private bool loadingDefaults;
    private int updateBatchSize;
    List<IDbCommand> commandBatch;

    /// <summary>
    /// Occurs during Update before a command is executed against the data source. The attempt to update is made, so the event fires.
    /// </summary>
    public event MySqlRowUpdatingEventHandler RowUpdating;

    /// <summary>
    /// Occurs during Update after a command is executed against the data source. The attempt to update is made, so the event fires.
    /// </summary>
    public event MySqlRowUpdatedEventHandler RowUpdated;

    public MySqlDataAdapter()
    {
      loadingDefaults = true;
      updateBatchSize = 1;
    }

    public MySqlDataAdapter(MySqlCommand selectCommand)
      : this()
    {
      SelectCommand = selectCommand;
    }


    public MySqlDataAdapter(string selectCommandText, MySqlConnection connection)
      : this()
    {
      SelectCommand = new MySqlCommand(selectCommandText, connection);
    }

    public MySqlDataAdapter(string selectCommandText, string selectConnString)
      : this()
    {
      SelectCommand = new MySqlCommand(selectCommandText,
        new MySqlConnection(selectConnString));
    }

#region Properties

    [Description("Used during Update for deleted rows in Dataset.")]
    public new MySqlCommand DeleteCommand
    {
      get { return (MySqlCommand)base.DeleteCommand; }
      set { base.DeleteCommand = value; }
    }

    [Description("Used during Update for new rows in Dataset.")]
    public new MySqlCommand InsertCommand
    {
      get { return (MySqlCommand)base.InsertCommand; }
      set { base.InsertCommand = value; }
    }

    [Description("Used during Fill/FillSchema")]
    [Category("Fill")]
    public new MySqlCommand SelectCommand
    {
      get { return (MySqlCommand)base.SelectCommand; }
      set { base.SelectCommand = value; }
    }

    [Description("Used during Update for modified rows in Dataset.")]
    public new MySqlCommand UpdateCommand
    {
      get { return (MySqlCommand)base.UpdateCommand; }
      set { base.UpdateCommand = value; }
    }

    internal bool LoadDefaults
    {
      get { return loadingDefaults; }
      set { loadingDefaults = value; }
    }

#endregion

    /// <summary>
    /// Open connection if it was closed.
    /// Necessary to workaround "connection must be open and valid" error
    /// with batched updates.
    /// </summary>
    /// <param name="state">Row state</param>
    /// <param name="openedConnections"> list of opened connections 
    /// If connection is opened by this function, the list is updated
    /// </param>
    /// <returns>true if connection was opened</returns>
    private void OpenConnectionIfClosed(DataRowState state,
      List<MySqlConnection> openedConnections)
    {
      MySqlCommand cmd = null;
      switch (state)
      {
        case DataRowState.Added:
          cmd = InsertCommand;
          break;
        case DataRowState.Deleted:
          cmd = DeleteCommand;
          break;
        case DataRowState.Modified:
          cmd = UpdateCommand;
          break;
        default:
          return;
      }

      if (cmd != null && cmd.Connection != null &&
        cmd.Connection.connectionState == ConnectionState.Closed)
      {
        cmd.Connection.Open();
        openedConnections.Add(cmd.Connection);
      }
    }


    protected override int Update(DataRow[] dataRows, DataTableMapping tableMapping)
    {

      List<MySqlConnection> connectionsOpened = new List<MySqlConnection>();

      try
      {
        // Open connections for insert/update/update commands, if 
        // connections are closed.
        foreach (DataRow row in dataRows)
        {
          OpenConnectionIfClosed(row.RowState, connectionsOpened);
        }

        int ret = base.Update(dataRows, tableMapping);

        return ret;
      }
      finally
      {
        foreach (MySqlConnection c in connectionsOpened)
          c.Close();
      }
    }


#region Batching Support

    public override int UpdateBatchSize
    {
      get { return updateBatchSize; }
      set { updateBatchSize = value; }
    }

    protected override void InitializeBatching()
    {
      commandBatch = new List<IDbCommand>();
    }

    protected override int AddToBatch(IDbCommand command)
    {
      // the first time each command is asked to be batched, we ask
      // that command to prepare its batchable command text.  We only want
      // to do this one time for each command
      MySqlCommand commandToBatch = (MySqlCommand)command;
      if (commandToBatch.BatchableCommandText == null)
        commandToBatch.GetCommandTextForBatching();

      IDbCommand cloneCommand = (IDbCommand)((ICloneable)command).Clone();
      commandBatch.Add(cloneCommand);

      return commandBatch.Count - 1;
    }

    protected override int ExecuteBatch()
    {
      int recordsAffected = 0;
      int index = 0;
      while (index < commandBatch.Count)
      {
        MySqlCommand cmd = (MySqlCommand)commandBatch[index++];
        for (int index2 = index; index2 < commandBatch.Count; index2++, index++)
        {
          MySqlCommand cmd2 = (MySqlCommand)commandBatch[index2];
          if (cmd2.BatchableCommandText == null ||
            cmd2.CommandText != cmd.CommandText) break;
          cmd.AddToBatch(cmd2);
        }
        recordsAffected += cmd.ExecuteNonQuery();
      }
      return recordsAffected;
    }

    protected override void ClearBatch()
    {
      if (commandBatch.Count > 0)
      {
        MySqlCommand cmd = (MySqlCommand)commandBatch[0];
        if (cmd.Batch != null)
          cmd.Batch.Clear();
      }
      commandBatch.Clear();
    }

    protected override void TerminateBatching()
    {
      ClearBatch();
      commandBatch = null;
    }

    protected override IDataParameter GetBatchedParameter(int commandIdentifier, int parameterIndex)
    {
      return (IDataParameter)commandBatch[commandIdentifier].Parameters[parameterIndex];
    }

#endregion

    /// <summary>
    /// Overridden. See <see cref="DbDataAdapter.CreateRowUpdatedEvent"/>.
    /// </summary>
    /// <param name="dataRow"></param>
    /// <param name="command"></param>
    /// <param name="statementType"></param>
    /// <param name="tableMapping"></param>
    /// <returns></returns>
    override protected RowUpdatedEventArgs CreateRowUpdatedEvent(DataRow dataRow, IDbCommand command, StatementType statementType, DataTableMapping tableMapping)
    {
      return new MySqlRowUpdatedEventArgs(dataRow, command, statementType, tableMapping);
    }

    /// <summary>
    /// Overridden. See <see cref="DbDataAdapter.CreateRowUpdatingEvent"/>.
    /// </summary>
    /// <param name="dataRow"></param>
    /// <param name="command"></param>
    /// <param name="statementType"></param>
    /// <param name="tableMapping"></param>
    /// <returns></returns>
    override protected RowUpdatingEventArgs CreateRowUpdatingEvent(DataRow dataRow, IDbCommand command, StatementType statementType, DataTableMapping tableMapping)
    {
      return new MySqlRowUpdatingEventArgs(dataRow, command, statementType, tableMapping);
    }

    /// <summary>
    /// Overridden. Raises the RowUpdating event.
    /// </summary>
    /// <param name="value">A MySqlRowUpdatingEventArgs that contains the event data.</param>
    override protected void OnRowUpdating(RowUpdatingEventArgs value)
    {
      if (RowUpdating != null)
        RowUpdating(this, (value as MySqlRowUpdatingEventArgs));
    }

    /// <summary>
    /// Overridden. Raises the RowUpdated event.
    /// </summary>
    /// <param name="value">A MySqlRowUpdatedEventArgs that contains the event data. </param>
    override protected void OnRowUpdated(RowUpdatedEventArgs value)
    {
      if (RowUpdated != null)
        RowUpdated(this, (value as MySqlRowUpdatedEventArgs));
    }

#if MYSQL_6_9
#region Async
#region Fill
    /// <summary>
    /// Async version of Fill
    /// </summary>
    /// <param name="dataSet">Dataset to use</param>
    /// <returns>int</returns>
    public Task<int> FillAsync(DataSet dataSet)
    {
      return FillAsync(dataSet, CancellationToken.None);
    }

    public Task<int> FillAsync(DataSet dataSet, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<int>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var fillResult = base.Fill(dataSet);
          result.SetResult(fillResult);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

    /// <summary>
    /// Async version of Fill
    /// </summary>
    /// <param name="dataTable">Datatable to use</param>
    /// <returns>int</returns>
    public Task<int> FillAsync(DataTable dataTable)
    {
      return FillAsync(dataTable, CancellationToken.None);
    }

    public Task<int> FillAsync(DataTable dataTable, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<int>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var fillResult = base.Fill(dataTable);
          result.SetResult(fillResult);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

    /// <summary>
    /// Async version of Fill
    /// </summary>
    /// <param name="dataSet">DataSet to use</param>
    /// <param name="srcTable">Source table</param>
    /// <returns>int</returns>
    public Task<int> FillAsync(DataSet dataSet, string srcTable)
    {
      return FillAsync(dataSet, srcTable, CancellationToken.None);
    }

    public Task<int> FillAsync(DataSet dataSet, string srcTable, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<int>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var fillResult = base.Fill(dataSet, srcTable);
          result.SetResult(fillResult);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

    /// <summary>
    /// Async version of Fill
    /// </summary>
    /// <param name="dataTable">Datatable to use</param>
    /// <param name="dataReader">DataReader to use</param>
    /// <returns>int</returns>
    public Task<int> FillAsync(DataTable dataTable, IDataReader dataReader)
    {
      return FillAsync(dataTable, dataReader, CancellationToken.None);
    }

    public Task<int> FillAsync(DataTable dataTable, IDataReader dataReader, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<int>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var fillResult = base.Fill(dataTable, dataReader);
          result.SetResult(fillResult);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

    /// <summary>
    /// Async version of Fill
    /// </summary>
    /// <param name="dataTable">DataTable to use</param>
    /// <param name="command">DbCommand to use</param>
    /// <param name="behavior">Command Behavior</param>
    /// <returns>int</returns>
    public Task<int> FillAsync(DataTable dataTable, IDbCommand command, CommandBehavior behavior)
    {
      return FillAsync(dataTable, command, behavior, CancellationToken.None);
    }

    public Task<int> FillAsync(DataTable dataTable, IDbCommand command, CommandBehavior behavior, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<int>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var fillResult = base.Fill(dataTable, command, behavior);
          result.SetResult(fillResult);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

    /// <summary>
    /// Async version of Fill
    /// </summary>
    /// <param name="startRecord">Start record</param>
    /// <param name="maxRecords">Max records</param>
    /// <param name="dataTables">DataTable[] to use</param>
    /// <returns>int</returns>
    public Task<int> FillAsync(int startRecord, int maxRecords, params DataTable[] dataTables)
    {
      return FillAsync(startRecord, maxRecords, CancellationToken.None, dataTables);
    }

    public Task<int> FillAsync(int startRecord, int maxRecords, CancellationToken cancellationToken, params DataTable[] dataTables)
    {
      var result = new TaskCompletionSource<int>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var fillResult = base.Fill(startRecord, maxRecords, dataTables);
          result.SetResult(fillResult);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

    /// <summary>
    /// Async version of Fill
    /// </summary>
    /// <param name="dataSet">DataSet to use</param>
    /// <param name="startRecord">Start record</param>
    /// <param name="maxRecords">Max records</param>
    /// <param name="srcTable">Source table</param>
    /// <returns>int</returns>
    public Task<int> FillAsync(DataSet dataSet, int startRecord, int maxRecords, string srcTable)
    {
      return FillAsync(dataSet, startRecord, maxRecords, srcTable, CancellationToken.None);
    }

    public Task<int> FillAsync(DataSet dataSet, int startRecord, int maxRecords, string srcTable, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<int>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var fillResult = base.Fill(dataSet, startRecord, maxRecords, srcTable);
          result.SetResult(fillResult);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

    /// <summary>
    /// Async version of Fill
    /// </summary>
    /// <param name="dataSet">DataSet to use</param>
    /// <param name="srcTable">Source table</param>
    /// <param name="dataReader">DataReader to use</param>
    /// <param name="startRecord">Start record</param>
    /// <param name="maxRecords">Max records</param>
    /// <returns></returns>
    public Task<int> FillAsync(DataSet dataSet, string srcTable, IDataReader dataReader, int startRecord, int maxRecords)
    {
      return FillAsync(dataSet, srcTable, dataReader, startRecord, maxRecords, CancellationToken.None);
    }

    public Task<int> FillAsync(DataSet dataSet, string srcTable, IDataReader dataReader, int startRecord, int maxRecords, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<int>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var fillResult = base.Fill(dataSet, srcTable, dataReader, startRecord, maxRecords);
          result.SetResult(fillResult);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

    /// <summary>
    /// Async version of Fill
    /// </summary>
    /// <param name="dataTables">DataTable[] to use</param>
    /// <param name="startRecord">Start record</param>
    /// <param name="maxRecords">Max records</param>
    /// <param name="command">DbCommand to use</param>
    /// <param name="behavior">Command Behavior</param>
    /// <returns></returns>
    public Task<int> FillAsync(DataTable[] dataTables, int startRecord, int maxRecords, IDbCommand command, CommandBehavior behavior)
    {
      return FillAsync(dataTables, startRecord, maxRecords, command, behavior, CancellationToken.None);
    }

    public Task<int> FillAsync(DataTable[] dataTables, int startRecord, int maxRecords, IDbCommand command, CommandBehavior behavior, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<int>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var fillResult = base.Fill(dataTables, startRecord, maxRecords, command, behavior);
          result.SetResult(fillResult);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

    /// <summary>
    /// Async version of Fill
    /// </summary>
    /// <param name="dataSet">DataSet to use</param>
    /// <param name="startRecord">Start record</param>
    /// <param name="maxRecords">Max records</param>
    /// <param name="srcTable">Source table</param>
    /// <param name="command">DbCommand to use</param>
    /// <param name="behavior">Command Behavior</param>
    /// <returns></returns>
    public Task<int> FillAsync(DataSet dataSet, int startRecord, int maxRecords, string srcTable, IDbCommand command, CommandBehavior behavior)
    {
      return FillAsync(dataSet, startRecord, maxRecords, srcTable, command, behavior, CancellationToken.None);
    }

    public Task<int> FillAsync(DataSet dataSet, int startRecord, int maxRecords, string srcTable, IDbCommand command, CommandBehavior behavior, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<int>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var fillResult = base.Fill(dataSet, startRecord, maxRecords, srcTable, command, behavior);
          result.SetResult(fillResult);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

#endregion

#region FillSchema
    /// <summary>
    /// Async version of FillSchema
    /// </summary>
    /// <param name="dataSet">DataSet to use</param>
    /// <param name="schemaType">Schema Type</param>
    /// <returns>DataTable[]</returns>
    public Task<DataTable[]> FillSchemaAsync(DataSet dataSet, SchemaType schemaType)
    {
      return FillSchemaAsync(dataSet, schemaType, CancellationToken.None);
    }

    public Task<DataTable[]> FillSchemaAsync(DataSet dataSet, SchemaType schemaType, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<DataTable[]>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var schemaResult = base.FillSchema(dataSet, schemaType);
          result.SetResult(schemaResult);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

    /// <summary>
    /// Async version of FillSchema
    /// </summary>
    /// <param name="dataSet">DataSet to use</param>
    /// <param name="schemaType">Schema Type</param>
    /// <param name="srcTable">Source Table</param>
    /// <returns>DataTable[]</returns>
    public Task<DataTable[]> FillSchemaAsync(DataSet dataSet, SchemaType schemaType, string srcTable)
    {
      return FillSchemaAsync(dataSet, schemaType, srcTable, CancellationToken.None);
    }

    public Task<DataTable[]> FillSchemaAsync(DataSet dataSet, SchemaType schemaType, string srcTable, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<DataTable[]>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var schemaResult = base.FillSchema(dataSet, schemaType, srcTable);
          result.SetResult(schemaResult);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

    /// <summary>
    /// Async version of FillSchema
    /// </summary>
    /// <param name="dataSet">DataSet to use</param>
    /// <param name="schemaType">Schema Type</param>
    /// <param name="srcTable">Source Table</param>
    /// <param name="dataReader">DataReader to use</param>
    /// <returns>DataTable[]</returns>
    public Task<DataTable[]> FillSchemaAsync(DataSet dataSet, SchemaType schemaType, string srcTable, IDataReader dataReader)
    {
      return FillSchemaAsync(dataSet, schemaType, srcTable, dataReader, CancellationToken.None);
    }

    public Task<DataTable[]> FillSchemaAsync(DataSet dataSet, SchemaType schemaType, string srcTable, IDataReader dataReader, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<DataTable[]>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var schemaResult = base.FillSchema(dataSet, schemaType, srcTable, dataReader);
          result.SetResult(schemaResult);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

    /// <summary>
    /// Async version of FillSchema
    /// </summary>
    /// <param name="dataSet">DataSet to use</param>
    /// <param name="schemaType">Schema Type</param>
    /// <param name="command">DBCommand to use</param>
    /// <param name="srcTable">Source Table</param>
    /// <param name="behavior">Command Behavior</param>
    /// <returns>DataTable[]</returns>
    public Task<DataTable[]> FillSchemaAsync(DataSet dataSet, SchemaType schemaType, IDbCommand command, string srcTable, CommandBehavior behavior)
    {
      return FillSchemaAsync(dataSet, schemaType, command, srcTable, behavior, CancellationToken.None);
    }

    public Task<DataTable[]> FillSchemaAsync(DataSet dataSet, SchemaType schemaType, IDbCommand command, string srcTable, CommandBehavior behavior, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<DataTable[]>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var schemaResult = base.FillSchema(dataSet, schemaType, command, srcTable, behavior);
          result.SetResult(schemaResult);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

    /// <summary>
    /// Async version of FillSchema
    /// </summary>
    /// <param name="dataTable">DataTable to use</param>
    /// <param name="schemaType">Schema Type</param>
    /// <returns>DataTable</returns>
    public Task<DataTable> FillSchemaAsync(DataTable dataTable, SchemaType schemaType)
    {
      return FillSchemaAsync(dataTable, schemaType, CancellationToken.None);
    }

    public Task<DataTable> FillSchemaAsync(DataTable dataTable, SchemaType schemaType, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<DataTable>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var schemaResult = base.FillSchema(dataTable, schemaType);
          result.SetResult(schemaResult);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

    /// <summary>
    /// Async version of FillSchema
    /// </summary>
    /// <param name="dataTable">DataTable to use</param>
    /// <param name="schemaType">Schema Type</param>
    /// <param name="dataReader">DataReader to use</param>
    /// <returns>DataTable</returns>
    public Task<DataTable> FillSchemaAsync(DataTable dataTable, SchemaType schemaType, IDataReader dataReader)
    {
      return FillSchemaAsync(dataTable, schemaType, dataReader, CancellationToken.None);
    }

    public Task<DataTable> FillSchemaAsync(DataTable dataTable, SchemaType schemaType, IDataReader dataReader, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<DataTable>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var schemaResult = base.FillSchema(dataTable, schemaType, dataReader);
          result.SetResult(schemaResult);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

    /// <summary>
    /// Async version of FillSchema
    /// </summary>
    /// <param name="dataTable">DataTable to use</param>
    /// <param name="schemaType">Schema Type</param>
    /// <param name="command">DBCommand to use</param>
    /// <param name="behavior">Command Behavior</param>
    /// <returns>DataTable</returns>
    public Task<DataTable> FillSchemaAsync(DataTable dataTable, SchemaType schemaType, IDbCommand command, CommandBehavior behavior)
    {
      return FillSchemaAsync(dataTable, schemaType, command, behavior, CancellationToken.None);
    }

    public Task<DataTable> FillSchemaAsync(DataTable dataTable, SchemaType schemaType, IDbCommand command, CommandBehavior behavior, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<DataTable>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var schemaResult = base.FillSchema(dataTable, schemaType, command, behavior);
          result.SetResult(schemaResult);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

#endregion

#region Update
    /// <summary>
    /// Async version of Update
    /// </summary>
    /// <param name="dataRows">DataRow[] to use</param>
    /// <returns>int</returns>
    public Task<int> UpdateAsync(DataRow[] dataRows)
    {
      return UpdateAsync(dataRows, CancellationToken.None);
    }

    public Task<int> UpdateAsync(DataRow[] dataRows, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<int>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var update = base.Update(dataRows);
          result.SetResult(update);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

    /// <summary>
    /// Async version of Update
    /// </summary>
    /// <param name="dataSet">DataSet to use</param>
    /// <returns>int</returns>
    public Task<int> UpdateAsync(DataSet dataSet)
    {
      return UpdateAsync(dataSet, CancellationToken.None);
    }

    public Task<int> UpdateAsync(DataSet dataSet, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<int>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var update = base.Update(dataSet);
          result.SetResult(update);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

    /// <summary>
    /// Async version of Update
    /// </summary>
    /// <param name="dataTable">DataTable to use</param>
    /// <returns>int</returns>
    public Task<int> UpdateAsync(DataTable dataTable)
    {
      return UpdateAsync(dataTable, CancellationToken.None);
    }

    public Task<int> UpdateAsync(DataTable dataTable, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<int>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var update = base.Update(dataTable);
          result.SetResult(update);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

    /// <summary>
    /// Async version of Update
    /// </summary>
    /// <param name="dataRows">DataRow[] to use</param>
    /// <param name="tableMapping">Data Table Mapping</param>
    /// <returns>int</returns>
    public Task<int> UpdateAsync(DataRow[] dataRows, DataTableMapping tableMapping)
    {
      return UpdateAsync(dataRows, tableMapping, CancellationToken.None);
    }

    public Task<int> UpdateAsync(DataRow[] dataRows, DataTableMapping tableMapping, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<int>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var update = base.Update(dataRows, tableMapping);
          result.SetResult(update);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

    /// <summary>
    /// Async version of Update
    /// </summary>
    /// <param name="dataSet">DataSet to use</param>
    /// <param name="srcTable">Source Table</param>
    /// <returns></returns>
    public Task<int> UpdateAsync(DataSet dataSet, string srcTable)
    {
      return UpdateAsync(dataSet, srcTable, CancellationToken.None);
    }

    public Task<int> UpdateAsync(DataSet dataSet, string srcTable, CancellationToken cancellationToken)
    {
      var result = new TaskCompletionSource<int>();
      if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
      {
        try
        {
          var update = base.Update(dataSet, srcTable);
          result.SetResult(update);
        }
        catch (Exception ex)
        {
          result.SetException(ex);
        }
      }
      else
      {
        result.SetCanceled();
      }
      return result.Task;
    }

#endregion
#endregion
#endif
  }

  /// <summary>
  /// Represents the method that will handle the <see cref="MySqlDataAdapter.RowUpdating"/> event of a <see cref="MySqlDataAdapter"/>.
  /// </summary>
  internal delegate void MySqlRowUpdatingEventHandler(object sender, MySqlRowUpdatingEventArgs e);

  /// <summary>
  /// Represents the method that will handle the <see cref="MySqlDataAdapter.RowUpdated"/> event of a <see cref="MySqlDataAdapter"/>.
  /// </summary>
  internal delegate void MySqlRowUpdatedEventHandler(object sender, MySqlRowUpdatedEventArgs e);

  /// <summary>
  /// Provides data for the RowUpdating event. This class cannot be inherited.
  /// </summary>
  internal sealed class MySqlRowUpdatingEventArgs : RowUpdatingEventArgs
  {
    /// <summary>
    /// Initializes a new instance of the MySqlRowUpdatingEventArgs class.
    /// </summary>
    /// <param name="row">The <see cref="DataRow"/> to 
    /// <see cref="DbDataAdapter.Update(DataSet)"/>.</param>
    /// <param name="command">The <see cref="IDbCommand"/> to execute during <see cref="DbDataAdapter.Update(DataSet)"/>.</param>
    /// <param name="statementType">One of the <see cref="StatementType"/> values that specifies the type of query executed.</param>
    /// <param name="tableMapping">The <see cref="DataTableMapping"/> sent through an <see cref="DbDataAdapter.Update(DataSet)"/>.</param>
    public MySqlRowUpdatingEventArgs(DataRow row, IDbCommand command, StatementType statementType, DataTableMapping tableMapping)
      : base(row, command, statementType, tableMapping)
    {
    }

    /// <summary>
    /// Gets or sets the MySqlCommand to execute when performing the Update.
    /// </summary>
    new public MySqlCommand Command
    {
      get { return (MySqlCommand)base.Command; }
      set { base.Command = value; }
    }
  }

  /// <summary>
  /// Provides data for the RowUpdated event. This class cannot be inherited.
  /// </summary>
  internal sealed class MySqlRowUpdatedEventArgs : RowUpdatedEventArgs
  {
    /// <summary>
    /// Initializes a new instance of the MySqlRowUpdatedEventArgs class.
    /// </summary>
    /// <param name="row">The <see cref="DataRow"/> sent through an <see cref="DbDataAdapter.Update(DataSet)"/>.</param>
    /// <param name="command">The <see cref="IDbCommand"/> executed when <see cref="DbDataAdapter.Update(DataSet)"/> is called.</param>
    /// <param name="statementType">One of the <see cref="StatementType"/> values that specifies the type of query executed.</param>
    /// <param name="tableMapping">The <see cref="DataTableMapping"/> sent through an <see cref="DbDataAdapter.Update(DataSet)"/>.</param>
    public MySqlRowUpdatedEventArgs(DataRow row, IDbCommand command, StatementType statementType, DataTableMapping tableMapping)
      : base(row, command, statementType, tableMapping)
    {
    }

    /// <summary>
    /// Gets or sets the MySqlCommand executed when Update is called.
    /// </summary>
    new public MySqlCommand Command
    {
      get { return (MySqlCommand)base.Command; }
    }
  }
}

#endif