using System;
using System.Data;
using System.Data.Common;
using EFCachingProvider.Caching;

namespace EFCachingProvider
{
///
/// Implementation of the  which reads the results of another data reader
/// and stores a copy in the cache.
///
internal class EFCachingDataReaderCacheWriter : EFCachingDataReaderBase
{
private DbQueryResults queryResults = new DbQueryResults();
private DbDataReader wrappedReader;
private int maxRows;
private Action addToCache;

///
/// Initializes a new instance of the EFCachingDataReaderCacheWriter class.
///
///
<span> </span>The wrapped reader.         ///
<span> </span>The maximum number of rows which can be cached.         ///
The delegate used to add the result to the cache when the reader finishes.         public EFCachingDataReaderCacheWriter(DbDataReader wrappedReader, int maxRows, Action addToCache)
{
this.wrappedReader = wrappedReader;
this.addToCache = addToCache;
this.maxRows = maxRows;
}

///
/// Gets a value that indicates whether this  contains one or more rows.
///
///
/// true if the  contains one or more rows; otherwise false.
///
public override bool HasRows
{
get { return this.wrappedReader.HasRows; }
}

///
/// Gets the number of rows changed, inserted, or deleted by execution of the SQL statement.
///
///
///
/// The number of rows changed, inserted, or deleted. -1 for SELECT statements; 0 if no rows were affected or the statement failed.
///
public override int RecordsAffected
{
//get { throw new NotImplementedException(); }
get { return this.wrappedReader.RecordsAffected; }
}

///
/// Gets a value indicating whether the  is closed.
///
///
/// true if the  is closed; otherwise false.
///
public override bool IsClosed
{
//get { throw new NotImplementedException(); }
get { return this.wrappedReader.IsClosed; }
}

///
/// Gets a value indicating the depth of nesting for the current row.
///
///
///
/// The depth of nesting for the current row.
///
public override int Depth
{
//get { throw new NotImplementedException(); }
get { return this.wrappedReader.Depth; }
}

///
/// Gets name of the data type of the specified column.
///
///
The zero-based column ordinal.         ///
/// A string representing the name of the data type.
///
public override string GetDataTypeName(int ordinal)
{
//throw new NotImplementedException();
return this.wrappedReader.GetDataTypeName(ordinal);
}

///
/// Gets the data type of the specified column.
///
///
The zero-based column ordinal.         /// The data type of the specified column.
public override Type GetFieldType(int ordinal)
{
return this.wrappedReader.GetFieldType(ordinal);
}

///
/// Gets the name of the column, given the zero-based column ordinal.
///
///
The zero-based column ordinal.         /// The name of the specified column.
public override string GetName(int ordinal)
{
return this.wrappedReader.GetName(ordinal);
}

///
/// Gets the column ordinal given the name of the column.
///
///
The name of the column.         /// The zero-based column ordinal.
///
/// The name specified is not a valid column name.
///
public override int GetOrdinal(string name)
{
return this.wrappedReader.GetOrdinal(name);
}

///
/// Returns a  that describes the column metadata of the .
///
///
/// A  that describes the column metadata.
///
public override DataTable GetSchemaTable()
{
return this.wrappedReader.GetSchemaTable();
}

///
/// Advances the reader to the next result when reading the results of a batch of statements.
///
///
/// true if there are more result sets; otherwise false.
///
public override bool NextResult()
{
if (this.wrappedReader.NextResult())
{
this.queryResults = null;
return true;
}
else
{
return false;
}
}

///
/// Closes the  object.
///
public override void Close()
{
this.wrappedReader.Close();

if (this.queryResults != null)
{
this.addToCache(this.queryResults);
}
}

///
/// Advances the reader to the next record in a result set.
///
///
/// true if there are more rows; otherwise false.
///
public override bool Read()
{
if (this.wrappedReader.Read())
{
object[] values = new object[this.wrappedReader.FieldCount];

this.wrappedReader.GetValues(values);
SetValues(values);
if (this.queryResults != null)
{
this.queryResults.Rows.Add(values);
if (this.queryResults.Rows.Count &gt; this.maxRows)
{
this.queryResults = null;
}
}

return true;
}
else
{
return false;
}
}
}
}