Kaidan/src/Database.h

135 lines
3.5 KiB
C++

/*
* Kaidan - A user-friendly XMPP client for every device!
*
* Copyright (C) 2016-2021 Kaidan developers and contributors
* (see the LICENSE file for a full list of copyright authors)
*
* Kaidan 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, either version 3 of the License, or
* (at your option) any later version.
*
* In addition, as a special exception, the author of Kaidan gives
* permission to link the code of its release with the OpenSSL
* project's "OpenSSL" library (or with modified versions of it that
* use the same license as the "OpenSSL" library), and distribute the
* linked executables. You must obey the GNU General Public License in
* all respects for all of the code used other than "OpenSSL". If you
* modify this file, you may extend this exception to your version of
* the file, but you are not obligated to do so. If you do not wish to
* do so, delete this exception statement from your version.
*
* Kaidan 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 Kaidan. If not, see <http://www.gnu.org/licenses/>.
*/
#pragma once
#include <QObject>
#include <QSqlDatabase>
class QSqlQuery;
/**
* The Database class manages the SQL database. It opens the database and converts old
* formats.
*/
class Database : public QObject
{
Q_OBJECT
public:
Database(QObject *parent = nullptr);
~Database();
/**
* Opens the database for reading and writing and guarantees the database to be
* up-to-date.
*/
void openDatabase();
/**
* Begins a transaction if none has been started.
*/
void transaction();
/**
* Commits the transaction if every transaction has been finished.
*/
void commit();
signals:
/// Emit, to begin a transaction if none has been started already.
void transactionRequested();
/// Emit, to commit the transaction if every transaction has been finished.
void commitRequested();
private:
/**
* @return true if the database has to be converted using @c convertDatabase()
* because the database is not up-to-date.
*/
bool needToConvert();
/**
* Converts the database to latest model.
*/
void convertDatabase();
/**
* Loads the database information and detects the database version.
*/
void loadDatabaseInfo();
/**
* Saves the database information.
*/
void saveDatabaseInfo();
/*
* These methods create new tables, they are used when creating a new database.
*/
void createDbInfoTable();
void createRosterTable();
void createMessagesTable();
/**
* Creates a new database without content.
*/
void createNewDatabase();
/*
* Upgrades the database to the next version.
*/
void convertDatabaseToV2();
void convertDatabaseToV3();
void convertDatabaseToV4();
void convertDatabaseToV5();
void convertDatabaseToV6();
void convertDatabaseToV7();
void convertDatabaseToV8();
void convertDatabaseToV9();
void convertDatabaseToV10();
void convertDatabaseToV11();
void convertDatabaseToV12();
void convertDatabaseToV13();
QSqlDatabase m_database;
/**
* -1 : Database not loaded.
* 0 : Database not existent.
* 1 : Old database before Kaidan v0.3.
* > 1 : Database version.
*/
int m_version = -1;
int m_transactions = 0;
};