/* Copyright (c) 2015, 2017, 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, version 2.0,
   as published by the Free Software Foundation.

   This program is also distributed with certain software (including
   but not limited to OpenSSL) that is licensed under separate terms,
   as designated in a particular file or component or in included license
   documentation.  The authors of MySQL hereby grant you an additional
   permission to link the program and your derivative works with the
   separately licensed software that they have included with MySQL.

   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, version 2.0, 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,
   51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA */

#ifndef SQL_SERVICE_INTERFACE_INCLUDE
#define SQL_SERVICE_INTERFACE_INCLUDE

#include "sql_service_context.h"

#define MAX_NUMBER_RETRIES 100
#define SESSION_WAIT_TIMEOUT 2

class Sql_service_interface
{
private:

  /** Pointer to Srv_session class */
  MYSQL_SESSION m_session;

  /** Pointer to the group_replication plugin structure */
  void *m_plugin;

  /** send result in string or native types */
  enum cs_text_or_binary m_txt_or_bin;

  /* The charset for the input string data */
  const CHARSET_INFO * m_charset;

  /**
    Executes a server command in a session.

    @param rset          resulted obtained after executing query
    @param cs_txt_bin    send result in string or native types
                         i.e. to CS_TEXT_REPRESENTATION or
                         CS_BINARY_REPRESENTATION
    @param cs_charset    charset for the string data input
    @param cmd           command service data input structure containing
                         command details (query/database/session id..).
                         Check include/mysql/com_data.h for more details.
    @param cmd_type      command type default set is COM_QUERY

    @return the sql error number
      @retval  0    OK
      @retval >0    SQL Error Number returned from MySQL Service API
      @retval -1    Internal server session failed or was killed
      @retval -2    Internal API failure
  */
  long
  execute_internal(Sql_resultset *rset,
                   enum cs_text_or_binary cs_txt_bin,
                   const CHARSET_INFO *cs_charset,
                   COM_DATA cmd,
                   enum enum_server_command cmd_type);

  /**
    Wait for server to be in SERVER_OPERATING state

    @param total_timeout    number of seconds to wait for
                            session server

    @return session server availability
      @retval   0   session server is in SERVER_OPERATING state
      @retval   1   timeout
      @retval  -1   session server shutdown in progress
  */
  int wait_for_session_server(ulong total_timeout);

public:

  /**
    Sql_service_interface constructor - Non-threaded version

    Initializes sql_service_context class

    @param cs_txt_bin    send result in string or native types
                         i.e. to CS_TEXT_REPRESENTATION or
                         CS_BINARY_REPRESENTATION
    @param cs_charset    charset for the string data input
  */
  Sql_service_interface(
                    enum cs_text_or_binary cs_txt_bin= CS_TEXT_REPRESENTATION,
                    const CHARSET_INFO *cs_charset= &my_charset_utf8_general_ci);


  /**
    Sql_service_interface destructor
  */
  ~Sql_service_interface();

  /**
    Opens an server session for internal server connection.

    @return the operation status
      @retval 0      OK
      @retval !=0    Error
  */
  int open_session();

  /**
    Opens an threaded server session for internal server connection.

    @param plugin_ptr a plugin pointer passed the connection thread.

    @return the operation status
      @retval 0      OK
      @retval !=0    Error
  */
  int open_thread_session(void *plugin_ptr);

  /**
    Executes a server command in a session.

    @note the command type here is COM_QUERY

    @param query_string  query to be executed

    @return the sql error number
      @retval  0    OK
      @retval >0    SQL Error Number returned from MySQL Service API
      @retval <0    local errors
  */
  long execute_query(std::string query_string);


  /**
    Executes a server command in a session.

    @param sql_string    query to be executed
    @param rset          resulted obtained after executing query
    @param cs_txt_bin    send result in string or native types
                         i.e. to CS_TEXT_REPRESENTATION or
                         CS_BINARY_REPRESENTATION
    @param cs_charset    charset for the string data input

    @note the command type here is COM_QUERY

    @return the sql error number
      @retval  0    OK
      @retval >0    SQL Error Number returned from MySQL Service API
      @retval <0    local errors
  */
  long execute_query(std::string sql_string,
                     Sql_resultset *rset,
                     enum cs_text_or_binary cs_txt_bin= CS_TEXT_REPRESENTATION,
                     const CHARSET_INFO *cs_charset= &my_charset_utf8_general_ci);

  /**
    Executes a server command in a session.

    @param cmd           command service data input structure containing
                         command details (query/database/session id..).
                         Check include/mysql/com_data.h for more details.
    @param cmd_type      command type default set is COM_QUERY
    @param rset          resulted obtained after executing query
    @param cs_txt_bin    send result in string or native types
                         i.e. to CS_TEXT_REPRESENTATION or
                         CS_BINARY_REPRESENTATION
    @param cs_charset    charset for the string data input

    @return the sql error number
      @retval  0    OK
      @retval >0    SQL Error Number returned from MySQL Service API
      @retval <0    local errors
  */
  long execute(COM_DATA cmd,
               enum enum_server_command cmd_type,
               Sql_resultset *rset,
               enum cs_text_or_binary cs_txt_bin= CS_TEXT_REPRESENTATION,
               const CHARSET_INFO *cs_charset= &my_charset_utf8_general_ci);


  /**
    Set send result type to CS_TEXT_REPRESENTATION or
    CS_BINARY_REPRESENTATION

    @param field_type  send result in string or native types
                       i.e. to CS_TEXT_REPRESENTATION or
                       CS_BINARY_REPRESENTATION
  */
  void set_send_resulttype(enum cs_text_or_binary field_type)
  {
    m_txt_or_bin= field_type;
  }

  /**
    set charset for the string data input(com_query for example)

    @param charset    charset for the string data input
  */
  void set_charset(const CHARSET_INFO * charset)
  {
    m_charset= charset;
  }

  /**
    Returns whether the session was killed

    @return
      @retval  0   not killed
      @retval  1   killed
  */
  int is_session_killed(MYSQL_SESSION session)
  {
    return srv_session_info_killed(session);
  }


  /**
    Returns the ID of a session.

    @return thread ID
  */
  uint64_t get_session_id()
  {
    return srv_session_info_get_session_id(m_session);
  }

  /**
    Returns the MYSQL_SESSION object.

    @return thread ID
  */
  MYSQL_SESSION get_session()
  {
    return m_session;
  }

  /**
    Set the session associated user.

    @param user the user to change to

    @return
      @retval  0   all ok
      @retval  1   error
  */
  int set_session_user(const char *user);

  /**
   Check if the server is running without user privileges

   @return
     @retval  true   the server is skipping the grant table
     @retval  false  user privileges are working normally
  */
  bool is_acl_disabled();
};

#endif //SQL_SERVICE_INTERFACE_INCLUDE
