#ifndef PLUGIN_QUERY_REWRITE_INCLUDED
#define PLUGIN_QUERY_REWRITE_INCLUDED

/* Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.

   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 */

#include "plugin.h"

/**
  @file include/mysql/plugin_query_rewrite.h
  API for the query rewrite plugin types (MYSQL_REWRITE_PRE_PARSE_PLUGIN and
  MYSQL_REWRITE_POST_PARSE_PLUGIN).
*/

/// Must be set by a plugin if the query is rewritten.
#define FLAG_REWRITE_PLUGIN_QUERY_REWRITTEN 1

/// Is set by the server if the query is prepared statement.
#define FLAG_REWRITE_PLUGIN_IS_PREPARED_STATEMENT 2

/// Structure that is passed during each step of a rewriting.
typedef struct Mysql_rewrite_post_parse_param
{
  /**
    Indicate the status of the current rewrite.
    @see FLAG_REWRITE_PLUGIN_QUERY_REWRITTEN
    @see FLAG_REWRITE_PLUGIN_IS_PREPARED_STATEMENT
  */
  int flags;

  /// The current session.
  MYSQL_THD thd;

  /// Pointer left to the plugin to store any necessary info as needed.
  void* data;
} Mysql_rewrite_post_parse_param;

struct st_mysql_rewrite_post_parse
{
  int interface_version;
  int needs_statement_digest;
  int (*rewrite)(Mysql_rewrite_post_parse_param *param);
};


/// Structure that is passed during each step of a rewriting.
typedef struct Mysql_rewrite_pre_parse_param
{
  /**
    Indicate the status of the current rewrite.
    @see FLAG_REWRITE_PLUGIN_QUERY_REWRITTEN
    @see FLAG_REWRITE_PLUGIN_IS_PREPARED_STATEMENT
  */
  int flags;

  /// The current session.
  MYSQL_THD thd;

  /// Pointer left to the plugin to store any necessary info as needed.
  void* data;

  /// The query potentially to be rewritten.
  const char* query;

  /// Length of query potentially to be rewritten.
  size_t query_length;

  /// The rewritten query, if applicable.
  const char* rewritten_query;

  /// Length of the rewritten query, if applicable.
  size_t rewritten_query_length;
} Mysql_rewrite_pre_parse_param;

struct st_mysql_rewrite_pre_parse
{
  int interface_version;
  int (*rewrite)(Mysql_rewrite_pre_parse_param *param);
  int (*deinit)(Mysql_rewrite_pre_parse_param *param);
};

#endif /* PLUGIN_QUERY_REWRITE_INCLUDED */
