// 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 MySql.Data.Types;
using System;
using System.Collections;
using System.Data;
using System.Data.Common;

namespace MySql.Data.MySqlClient
{
  public sealed partial class MySqlDataReader : DbDataReader, IDataReader, IDataRecord
  {
    /// <summary>
    /// Gets a value indicating the depth of nesting for the current row.  This method is not 
    /// supported currently and always returns 0.
    /// </summary>
    public override int Depth
    {
      get { return 0; }
    }

#if !CF
    public MySqlGeometry GetMySqlGeometry(int i)
    {
      try
      {
        IMySqlValue v = GetFieldValue(i, false);
        if (v is MySqlGeometry || v is MySqlBinary)
          return new MySqlGeometry(MySqlDbType.Geometry, (Byte[])v.Value);
      }
      catch
      {
        Throw(new Exception("Can't get MySqlGeometry from value"));
      }
      return new MySqlGeometry(true);
    }

    public MySqlGeometry GetMySqlGeometry(string column)
    {
      return GetMySqlGeometry(GetOrdinal(column));
    }
#endif

    /// <summary>
    /// Returns a DataTable that describes the column metadata of the MySqlDataReader.
    /// </summary>
    /// <returns></returns>
    public override DataTable GetSchemaTable()
    {
      // Only Results from SQL SELECT Queries 
      // get a DataTable for schema of the result
      // otherwise, DataTable is null reference
      if (FieldCount == 0) return null;

      DataTable dataTableSchema = new DataTable("SchemaTable");

      dataTableSchema.Columns.Add("ColumnName", typeof(string));
      dataTableSchema.Columns.Add("ColumnOrdinal", typeof(int));
      dataTableSchema.Columns.Add("ColumnSize", typeof(int));
      dataTableSchema.Columns.Add("NumericPrecision", typeof(int));
      dataTableSchema.Columns.Add("NumericScale", typeof(int));
      dataTableSchema.Columns.Add("IsUnique", typeof(bool));
      dataTableSchema.Columns.Add("IsKey", typeof(bool));
      DataColumn dc = dataTableSchema.Columns["IsKey"];
      dc.AllowDBNull = true; // IsKey can have a DBNull
      dataTableSchema.Columns.Add("BaseCatalogName", typeof(string));
      dataTableSchema.Columns.Add("BaseColumnName", typeof(string));
      dataTableSchema.Columns.Add("BaseSchemaName", typeof(string));
      dataTableSchema.Columns.Add("BaseTableName", typeof(string));
      dataTableSchema.Columns.Add("DataType", typeof(Type));
      dataTableSchema.Columns.Add("AllowDBNull", typeof(bool));
      dataTableSchema.Columns.Add("ProviderType", typeof(int));
      dataTableSchema.Columns.Add("IsAliased", typeof(bool));
      dataTableSchema.Columns.Add("IsExpression", typeof(bool));
      dataTableSchema.Columns.Add("IsIdentity", typeof(bool));
      dataTableSchema.Columns.Add("IsAutoIncrement", typeof(bool));
      dataTableSchema.Columns.Add("IsRowVersion", typeof(bool));
      dataTableSchema.Columns.Add("IsHidden", typeof(bool));
      dataTableSchema.Columns.Add("IsLong", typeof(bool));
      dataTableSchema.Columns.Add("IsReadOnly", typeof(bool));

      int ord = 1;
      for (int i = 0; i < FieldCount; i++)
      {
        MySqlField f = resultSet.Fields[i];
        DataRow r = dataTableSchema.NewRow();
        r["ColumnName"] = f.ColumnName;
        r["ColumnOrdinal"] = ord++;
        r["ColumnSize"] = f.IsTextField ? f.ColumnLength / f.MaxLength : f.ColumnLength;
        int prec = f.Precision;
        int pscale = f.Scale;
        if (prec != -1)
          r["NumericPrecision"] = (short)prec;
        if (pscale != -1)
          r["NumericScale"] = (short)pscale;
        r["DataType"] = GetFieldType(i);
        r["ProviderType"] = (int)f.Type;
        r["IsLong"] = f.IsBlob && f.ColumnLength > 255;
        r["AllowDBNull"] = f.AllowsNull;
        r["IsReadOnly"] = false;
        r["IsRowVersion"] = false;
        r["IsUnique"] = false;
        r["IsKey"] = f.IsPrimaryKey;
        r["IsAutoIncrement"] = f.IsAutoIncrement;
        r["BaseSchemaName"] = f.DatabaseName;
        r["BaseCatalogName"] = null;
        r["BaseTableName"] = f.RealTableName;
        r["BaseColumnName"] = f.OriginalColumnName;

        dataTableSchema.Rows.Add(r);
      }

      return dataTableSchema;
    }

    /// <summary>
    /// Returns an <see cref="IEnumerator"/> that iterates through the <see cref="MySqlDataReader"/>. 
    /// </summary>
    /// <returns></returns>
    public override IEnumerator GetEnumerator()
    {
      return new DbEnumerator(this, (commandBehavior & CommandBehavior.CloseConnection) != 0);
    }
  }
}
