/* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
 *  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
 *
 *  Copyright (C) 2008 Sun Microsystems
 *
 *  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
 */


#ifndef DRIZZLED_FOREIGN_KEY_H
#define DRIZZLED_FOREIGN_KEY_H

#include <drizzled/sql_alloc.h>
#include <drizzled/key.h>
#include <drizzled/sql_list.h>

class Item;
class Table_ident;

typedef struct st_mem_root MEM_ROOT;

class Foreign_key: public Key {
public:
  enum fk_match_opt 
  {
    FK_MATCH_UNDEF, 
    FK_MATCH_FULL, 
    FK_MATCH_PARTIAL, 
    FK_MATCH_SIMPLE
  };
  enum fk_option 
  {
    FK_OPTION_UNDEF, 
    FK_OPTION_RESTRICT, 
    FK_OPTION_CASCADE, 
    FK_OPTION_SET_NULL, 
    FK_OPTION_NO_ACTION, 
    FK_OPTION_DEFAULT
  };

  Table_ident *ref_table;
  List<Key_part_spec> ref_columns;
  uint32_t delete_opt, update_opt, match_opt;
  Foreign_key(const LEX_STRING &name_arg,
              List<Key_part_spec> &cols,
              Table_ident *table,
              List<Key_part_spec> &ref_cols,
              uint32_t delete_opt_arg,
              uint32_t update_opt_arg,
              uint32_t match_opt_arg) :
    Key(FOREIGN_KEY, name_arg, &default_key_create_info, 0, cols), ref_table(table),
    ref_columns(ref_cols),
    delete_opt(delete_opt_arg),
    update_opt(update_opt_arg),
    match_opt(match_opt_arg)
  { }


  /**
   * Constructs an (almost) deep copy of this foreign key. Only those
   * elements that are known to never change are not copied.
   * If out of memory, a partial copy is returned and an error is set
   * in Session.
   */
  Foreign_key(const Foreign_key &rhs, MEM_ROOT *mem_root);


  /**
   * Used to make a clone of this object for ALTER/CREATE TABLE
   * 
   * @see comment for Key_part_spec::clone
   */
  virtual Key *clone(MEM_ROOT *mem_root) const
  {
    return new (mem_root) Foreign_key(*this, mem_root);
  }


  /* Used to validate foreign key options */
  bool validate(List<CreateField> &table_fields);
};

#endif /* DRIZZLED_FOREIGN_KEY_H */