/* Copyright (c) 2013, 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 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,
   51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA */

#ifndef OBSERVER_TRANS
#define OBSERVER_TRANS

#include <mysql/gcs/gcs_communication_interface.h>
#include "gcs_plugin_messages.h"
#include "plugin.h"

/**
  Initialize transactions observer structures.
*/
void observer_trans_initialize();

/**
  Terminate transactions observer structures.
*/
void observer_trans_terminate();

/**
  Clear server sessions opened caches.
*/
void observer_trans_clear_io_cache_unused_list();

/*
  Transaction lifecycle events observers.
*/
int group_replication_trans_before_dml(Trans_param *param, int& out);

int group_replication_trans_before_commit(Trans_param *param);

int group_replication_trans_before_rollback(Trans_param *param);

int group_replication_trans_after_commit(Trans_param *param);

int group_replication_trans_after_rollback(Trans_param *param);

extern Trans_observer trans_observer;

/*
  @class Transaction_Message
  Class to convey the serialized contents of the TCLE
 */
class Transaction_Message: public Plugin_gcs_message
{
public:
  enum enum_payload_item_type
  {
    // This type should not be used anywhere.
    PIT_UNKNOWN= 0,

    // Length of the payload item: variable
    PIT_TRANSACTION_DATA= 1,

    // No valid type codes can appear after this one.
    PIT_MAX= 2
  };

  /**
   Default constructor
   */
  Transaction_Message();
  virtual ~Transaction_Message();

  /**
    Appends IO_CACHE data to the internal buffer

    @param[in] src the IO_CACHE to copy data from

    @return true in case of error
   */
  bool append_cache(IO_CACHE *src);

protected:
  /*
   Implementation of the template methods
   */
  void encode_payload(std::vector<unsigned char>* buffer) const;
  void decode_payload(const unsigned char* buffer, const unsigned char* length);

private:
  std::vector<uchar> data;
};

/**
  Broadcasts the Transaction Message

  @param msg the message to broadcast

  @return the communication engine broadcast message error
    @retval GCS_OK, when message is transmitted successfully
    @retval GCS_NOK, when error occurred while transmitting message
    @retval GCS_MESSAGE_TOO_BIG, when message is bigger than
                                 communication engine can handle
 */
enum enum_gcs_error send_transaction_message(Transaction_Message* msg);

#endif /* OBSERVER_TRANS */