transaction.hpp

//
// Copyright (c) 2024 Klemens Morgenstern (klemens.morgenstern@gmx.net)
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//

#ifndef BOOST_SQLITE_TRANSACTION_HPP
#define BOOST_SQLITE_TRANSACTION_HPP

#include <boost/sqlite/connection.hpp>

BOOST_SQLITE_BEGIN_NAMESPACE

struct transaction
{
  enum behaviour {deferred, immediate, exclusive};
  constexpr static struct adopt_transaction_t {} adopt_transaction;

  transaction(connection & conn, adopt_transaction_t) : conn_(conn), completed_(false)
  {
  }


  transaction(connection & conn) : conn_(conn)
  {
    conn.execute("BEGIN");
    completed_ = false;
  }

  transaction(connection & conn, behaviour b) : conn_(conn)
  {
    switch (b)
    {
      case deferred:  conn.execute("BEGIN DEFERRED"); break;
      case immediate: conn.execute("BEGIN IMMEDIATE"); break;
      case exclusive: conn.execute("BEGIN EXCLUSIVE"); break;
    }
    completed_ = false;
  }

  ~transaction() noexcept(false)
  {
    if (!completed_)
      conn_.execute("ROLLBACK");
  }

  void commit()
  {
    conn_.execute("COMMIT");
    completed_ = true;
  }

  void rollback()
  {
    conn_.execute("ROLLBACK");
    completed_ = true;
  }

  void commit(system::error_code & ec, error_info & ei)
  {
    conn_.execute("COMMIT", ec, ei);
    completed_ = true;
  }

  void rollback(system::error_code & ec, error_info & ei)
  {
    conn_.execute("ROLLBACK", ec, ei);
    completed_ = true;
  }

 private:
  connection & conn_;
  bool completed_ = true;
};


struct savepoint
{
  enum behaviour {deferred, immediate, exclusive};
  constexpr static transaction::adopt_transaction_t adopt_transaction;

  savepoint(connection & conn, std::string name, transaction::adopt_transaction_t)
      : conn_(conn), name_(std::move(name))
  {
  }

  savepoint(connection & conn, std::string name) : conn_(conn), name_(std::move(name))
  {
    conn.execute("SAVEPOINT " + name);
    completed_ = false;
  }


  ~savepoint() noexcept(false)
  {
    if (!completed_)
      conn_.execute("ROLLBACK TO " + name_);
  }

  void commit()
  {
    conn_.execute("RELEASE " + name_);
    completed_ = true;
  }

  void release()
  {
    conn_.execute("RELEASE " + name_);
    completed_ = true;
  }


  void rollback()
  {
    conn_.execute("ROLLBACK TO" + name_);
    completed_ = true;
  }

  void commit(system::error_code & ec, error_info & ei)
  {
    conn_.execute("RELEASE " + name_, ec, ei);
    completed_ = true;
  }

  void release(system::error_code & ec, error_info & ei)
  {
    conn_.execute("RELEASE " + name_, ec, ei);
    completed_ = true;
  }

  void rollback(system::error_code & ec, error_info & ei)
  {
    conn_.execute("ROLLBACK TO " + name_, ec, ei);
    completed_ = true;
  }

  const std::string & name() const {return name_;}
 private:
  connection & conn_;
  std::string name_;
  bool completed_ = true;
};


BOOST_SQLITE_END_NAMESPACE

#endif //BOOST_SQLITE_TRANSACTION_HPP