// Copyright © 2004, 2013, 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

using System;
using System.ComponentModel;
using System.Data.Common;
using System.Data;
using System.Text;
using MySql.Data.Common;
using System.Collections;
using MySql.Data.Types;
using System.Globalization;
using MySql.Data.MySqlClient.Properties;
using System.Collections.Generic;

namespace MySql.Data.MySqlClient
{
  /// <include file='docs/MySqlCommandBuilder.xml' path='docs/class/*'/>
#if !CF && !RT
  [ToolboxItem(false)]
  [System.ComponentModel.DesignerCategory("Code")]
#endif
  public sealed class MySqlCommandBuilder : DbCommandBuilder
  {
    /// <include file='docs/MySqlCommandBuilder.xml' path='docs/Ctor/*'/>
    public MySqlCommandBuilder()
    {
      QuotePrefix = QuoteSuffix = "`";
    }

    /// <include file='docs/MySqlCommandBuilder.xml' path='docs/Ctor2/*'/>
    public MySqlCommandBuilder(MySqlDataAdapter adapter)
      : this()
    {
      DataAdapter = adapter;
    }

    /// <include file='docs/mysqlcommandBuilder.xml' path='docs/DataAdapter/*'/>
    public new MySqlDataAdapter DataAdapter
    {
      get { return (MySqlDataAdapter)base.DataAdapter; }
      set { base.DataAdapter = value; }
    }

    #region Public Methods

    /// <summary>
    /// Retrieves parameter information from the stored procedure specified 
    /// in the MySqlCommand and populates the Parameters collection of the 
    /// specified MySqlCommand object.
    /// This method is not currently supported since stored procedures are 
    /// not available in MySql.
    /// </summary>
    /// <param name="command">The MySqlCommand referencing the stored 
    /// procedure from which the parameter information is to be derived. 
    /// The derived parameters are added to the Parameters collection of the 
    /// MySqlCommand.</param>
    /// <exception cref="InvalidOperationException">The command text is not 
    /// a valid stored procedure name.</exception>
    public static void DeriveParameters(MySqlCommand command)
    {
      if (command.CommandType != CommandType.StoredProcedure)
        throw new InvalidOperationException(Resources.CanNotDeriveParametersForTextCommands);

      // retrieve the proc definition from the cache.
      string spName = command.CommandText;
      if (spName.IndexOf(".") == -1)
        spName = command.Connection.Database + "." + spName;

      try
      {
        ProcedureCacheEntry entry = command.Connection.ProcedureCache.GetProcedure(command.Connection, spName, null);
        command.Parameters.Clear();
        foreach (MySqlSchemaRow row in entry.parameters.Rows)
        {
          MySqlParameter p = new MySqlParameter();
          p.ParameterName = String.Format("@{0}", row["PARAMETER_NAME"]);
          if (row["ORDINAL_POSITION"].Equals(0) && p.ParameterName == "@")
            p.ParameterName = "@RETURN_VALUE";
          p.Direction = GetDirection(row);
          bool unsigned = StoredProcedure.GetFlags(row["DTD_IDENTIFIER"].ToString()).IndexOf("UNSIGNED") != -1;
          bool real_as_float = entry.procedure.Rows[0]["SQL_MODE"].ToString().IndexOf("REAL_AS_FLOAT") != -1;
          p.MySqlDbType = MetaData.NameToType(row["DATA_TYPE"].ToString(),
            unsigned, real_as_float, command.Connection);
          if (row["CHARACTER_MAXIMUM_LENGTH"] != null )
            p.Size = (int)row["CHARACTER_MAXIMUM_LENGTH"];
          if (row["NUMERIC_PRECISION"] != null)
            p.Precision = Convert.ToByte(row["NUMERIC_PRECISION"]);
          if (row["NUMERIC_SCALE"] != null )
            p.Scale = Convert.ToByte(row["NUMERIC_SCALE"]);
          if (p.MySqlDbType == MySqlDbType.Set || p.MySqlDbType == MySqlDbType.Enum)
            p.PossibleValues = GetPossibleValues(row);
          command.Parameters.Add(p);
        }
      }
      catch (InvalidOperationException ioe)
      {
        throw new MySqlException(Resources.UnableToDeriveParameters, ioe);
      }
    }

    private static List<string> GetPossibleValues(MySqlSchemaRow row)
    {
      string[] types = new string[] { "ENUM", "SET" };
      string dtdIdentifier = row["DTD_IDENTIFIER"].ToString().Trim();

      int index = 0;
      for (; index < 2; index++)
        if (dtdIdentifier.StartsWith(types[index], StringComparison.OrdinalIgnoreCase ))
          break;
      if (index == 2) return null;
      dtdIdentifier = dtdIdentifier.Substring(types[index].Length).Trim();
      dtdIdentifier = dtdIdentifier.Trim('(', ')').Trim();

      List<string> values = new List<string>();
      MySqlTokenizer tokenzier = new MySqlTokenizer(dtdIdentifier);
      string token = tokenzier.NextToken();
      int start = tokenzier.StartIndex;
      while (true)
      {
        if (token == null || token == ",")
        {
          int end = dtdIdentifier.Length - 1;
          if (token == ",")
            end = tokenzier.StartIndex;

          string value = dtdIdentifier.Substring(start, end - start).Trim('\'', '\"').Trim();
          values.Add(value);
          start = tokenzier.StopIndex;
        }
        if (token == null) break;
        token = tokenzier.NextToken();
      }
      return values;
    }

    private static ParameterDirection GetDirection(MySqlSchemaRow row)
    {
      string mode = row["PARAMETER_MODE"].ToString();
      int ordinal = Convert.ToInt32(row["ORDINAL_POSITION"]);

      if (0 == ordinal)
        return ParameterDirection.ReturnValue;
      else if (mode == "IN")
        return ParameterDirection.Input;
      else if (mode == "OUT")
        return ParameterDirection.Output;
      return ParameterDirection.InputOutput;
    }

    /// <summary>
    /// Gets the delete command.
    /// </summary>
    /// <returns></returns>
    public new MySqlCommand GetDeleteCommand()
    {
      return (MySqlCommand)base.GetDeleteCommand();
    }

    /// <summary>
    /// Gets the update command.
    /// </summary>
    /// <returns></returns>
    public new MySqlCommand GetUpdateCommand()
    {
      return (MySqlCommand)base.GetUpdateCommand();
    }

    /// <summary>
    /// Gets the insert command.
    /// </summary>
    /// <returns></returns>
    public new MySqlCommand GetInsertCommand()
    {
      return (MySqlCommand)GetInsertCommand(false);
    }

    public override string QuoteIdentifier(string unquotedIdentifier)
    {
      if (unquotedIdentifier == null) throw new
        ArgumentNullException("unquotedIdentifier");

      // don't quote again if it is already quoted
      if (unquotedIdentifier.StartsWith(QuotePrefix) &&
        unquotedIdentifier.EndsWith(QuoteSuffix))
        return unquotedIdentifier;

      unquotedIdentifier = unquotedIdentifier.Replace(QuotePrefix, QuotePrefix + QuotePrefix);

      return String.Format("{0}{1}{2}", QuotePrefix, unquotedIdentifier, QuoteSuffix);
    }

    public override string UnquoteIdentifier(string quotedIdentifier)
    {
      if (quotedIdentifier == null) throw new
        ArgumentNullException("quotedIdentifier");

      // don't unquote again if it is already unquoted
      if (!quotedIdentifier.StartsWith(QuotePrefix) ||
        !quotedIdentifier.EndsWith(QuoteSuffix))
        return quotedIdentifier;

      if (quotedIdentifier.StartsWith(QuotePrefix))
        quotedIdentifier = quotedIdentifier.Substring(1);
      if (quotedIdentifier.EndsWith(QuoteSuffix))
        quotedIdentifier = quotedIdentifier.Substring(0, quotedIdentifier.Length - 1);

      quotedIdentifier = quotedIdentifier.Replace(QuotePrefix + QuotePrefix, QuotePrefix);

      return quotedIdentifier;
    }

    #endregion

    protected override DataTable GetSchemaTable(DbCommand sourceCommand)
    {
      DataTable schemaTable = base.GetSchemaTable(sourceCommand);

      foreach (DataRow row in schemaTable.Rows)
        if (row["BaseSchemaName"].Equals(sourceCommand.Connection.Database))
          row["BaseSchemaName"] = null;

      return schemaTable;
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="parameterName"></param>
    /// <returns></returns>
    protected override string GetParameterName(string parameterName)
    {
      StringBuilder sb = new StringBuilder(parameterName);
      sb.Replace(" ", "");
      sb.Replace("/", "_per_");
      sb.Replace("-", "_");
      sb.Replace(")", "_cb_");
      sb.Replace("(", "_ob_");
      sb.Replace("%", "_pct_");
      sb.Replace("<", "_lt_");
      sb.Replace(">", "_gt_");
      sb.Replace(".", "_pt_");
      return String.Format("@{0}", sb.ToString());
    }

    protected override void ApplyParameterInfo(DbParameter parameter, DataRow row,
      StatementType statementType, bool whereClause)
    {
      ((MySqlParameter)parameter).MySqlDbType = (MySqlDbType)row["ProviderType"];
    }

    protected override string GetParameterName(int parameterOrdinal)
    {
      return String.Format("@p{0}", parameterOrdinal.ToString(CultureInfo.InvariantCulture));
    }

    protected override string GetParameterPlaceholder(int parameterOrdinal)
    {
      return String.Format("@p{0}", parameterOrdinal.ToString(CultureInfo.InvariantCulture));
    }

    protected override void SetRowUpdatingHandler(DbDataAdapter adapter)
    {
      MySqlDataAdapter myAdapter = (adapter as MySqlDataAdapter);
      if (adapter != base.DataAdapter)
        myAdapter.RowUpdating += new MySqlRowUpdatingEventHandler(RowUpdating);
      else
        myAdapter.RowUpdating -= new MySqlRowUpdatingEventHandler(RowUpdating);
    }

    private void RowUpdating(object sender, MySqlRowUpdatingEventArgs args)
    {
      base.RowUpdatingHandler(args);
    }

  }
}
