// SqlResult.h

#ifndef SqlResult_H
#define SqlResult_H

#include "dataset_sql/SqlQuery.h"
#include "dataset_sql/SelectQuery.h"
#include "dataset_sql/InsertQuery.h"
#include "dataset_sql/DeleteQuery.h"
#include <vector>
#include <iosfwd>

// Chitra Kannan and Vinay Sambamurthy
// June 2004
//
// Class to describe the result of an SQL query. 
// The result is invalid if the input query is invalid

namespace dset {

class SqlResult { 

public: // Typedefs.

  typedef std::vector<std::string> NameList;
  typedef SqlRow Row;
  typedef std::vector<Row> Result;
  typedef Result::size_type size_type;
  
private: // Data members.

  NameList m_names;
  Result m_result;
  mutable bool m_valid;

public: // Methods.
	
  // Constructor.
  SqlResult();

  // Constructor.
  SqlResult(NameList& names);

  // Copy Constructor.
  SqlResult(const SqlResult& res);

  // Destructor.
  ~SqlResult();	

  // Validity.
  bool is_valid() const;
 
  // Check validity of columns
  bool check_valid_cols(NameList& cols) const;

  // Insert a new row.
  // Returns 0 on success. 
  int insert_row(const Row& row);	

  // Return the number of rows.
  size_type num_rows() const;

  // Return the number of columns.
  int num_cols() const;

  // Return the names of columns.
  NameList get_col_names() const;

  // Return the vector of rows.
  Result get_rows() const;

  // Return the specified row.
  // Return an empty row if invalid index.
  const Row& fetch_row(unsigned int index) const;

  // Return the SqlResult after execution of a SELECT SqlQuery.
  SqlResult execute_select_query(const SelectQuery query) const;	

  // Return the SqlResult after execution of a INSERT SqlQuery.
  int execute_insert_query(const InsertQuery query);	

  // Return the SqlResult after execution of a UPDATE SqlQuery.
  int execute_update_query(const InsertQuery query, const SelectQuery 
								selquery);	
  // Return the SqlResult after execution of a DELETE SqlQuery.
  int execute_delete_query(const DeleteQuery query);	

  // Output stream.
  std::ostream& ostr(std::ostream& str) const;

};

} // end dset namespace.

// Output stream.
std::ostream& operator<<(std::ostream& lhs, const dset::SqlResult& rhs);

#endif