File indexing completed on 2025-01-05 03:54:13

 /* ============================================================
  *
  * This file is a part of digiKam project
  * https://www.digikam.org
  *
  * Date        : 2017-06-28
  * Description : Similarity Database access wrapper.
  *
  * SPDX-FileCopyrightText: 2007-2008 by Marcel Wiesweg <marcel dot wiesweg at gmx dot de>
  * SPDX-FileCopyrightText: 2010-2024 by Gilles Caulier <caulier dot gilles at gmail dot com>
  * SPDX-FileCopyrightText:      2017 by Swati  Lodha   <swatilodha27 at gmail dot com>
  * SPDX-FileCopyrightText:      2018 by Mario Frank    <mario dot frank at uni minus potsdam dot de>
  *
  * SPDX-License-Identifier: GPL-2.0-or-later
  *
  * ============================================================ */
 
 #include "similaritydbaccess.h"
 
 // Qt includes
 
 #include <QMutex>
 #include <QMutexLocker>
 #include <QSqlDatabase>
 
 // KDE includes
 
 #include <klocalizedstring.h>
 
 // Local includes
 
 #include "digikam_debug.h"
 #include "similaritydbbackend.h"
 #include "similaritydb.h"
 #include "similaritydbschemaupdater.h"
 #include "dbengineaccess.h"
 #include "dbengineerrorhandler.h"
 
 namespace Digikam
 {
 
 class Q_DECL_HIDDEN SimilarityDbAccessStaticPriv
 {
 public:
 
     SimilarityDbAccessStaticPriv()
         : backend     (nullptr),
           db          (nullptr),
           initializing(false)
     {
     }
 
     ~SimilarityDbAccessStaticPriv()
     {
     };
 
     SimilarityDbBackend* backend;
     SimilarityDb*        db;
     DbEngineParameters   parameters;
     DbEngineLocking      lock;
     QString              lastError;
 
     bool                 initializing;
 };
 
 SimilarityDbAccessStaticPriv* SimilarityDbAccess::d = nullptr;
 
 // -----------------------------------------------------------------------------
 
 class Q_DECL_HIDDEN SimilarityDbAccessMutexLocker
 
 #if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
 
     : public QMutexLocker<QRecursiveMutex>
 
 #else
 
     : public QMutexLocker
 
 #endif
 
 {
 public:
 
     explicit SimilarityDbAccessMutexLocker(SimilarityDbAccessStaticPriv* const dd)
         : QMutexLocker(&dd->lock.mutex),
           d           (dd)
     {
         d->lock.lockCount++;
     }
 
     ~SimilarityDbAccessMutexLocker()
     {
         d->lock.lockCount--;
     }
 
 public:
 
     SimilarityDbAccessStaticPriv* const d;
 };
 
 // -----------------------------------------------------------------------------
 
 SimilarityDbAccess::SimilarityDbAccess()
 {
     // You will want to call setParameters before constructing SimilarityDbAccess.
 
     Q_ASSERT(d);
 
     d->lock.mutex.lock();
     d->lock.lockCount++;
 
     if (!d->backend->isOpen() && !d->initializing)
     {
         // avoid endless loops
 
         d->initializing = true;
 
         d->backend->open(d->parameters);
 
         d->initializing = false;
     }
 }
 
 SimilarityDbAccess::~SimilarityDbAccess()
 {
     d->lock.lockCount--;
     d->lock.mutex.unlock();
 }
 
 SimilarityDbAccess::SimilarityDbAccess(bool)
 {
     // private constructor, when mutex is locked and
     // backend should not be checked
 
     d->lock.mutex.lock();
     d->lock.lockCount++;
 }
 
 SimilarityDb* SimilarityDbAccess::db() const
 {
     return d->db;
 }
 
 SimilarityDbBackend* SimilarityDbAccess::backend() const
 {
     return d->backend;
 }
 
 DbEngineParameters SimilarityDbAccess::parameters()
 {
     if (d)
     {
         return d->parameters;
     }
 
     return DbEngineParameters();
 }
 
 bool SimilarityDbAccess::isInitialized()
 {
     return d;
 }
 
 void SimilarityDbAccess::initDbEngineErrorHandler(DbEngineErrorHandler* const errorhandler)
 {
     if (!d)
     {
         d = new SimilarityDbAccessStaticPriv();
     }
 
     //DbEngineErrorHandler* const errorhandler = new DbEngineGuiErrorHandler(d->parameters);
 
     d->backend->setDbEngineErrorHandler(errorhandler);
 }
 
 void SimilarityDbAccess::setParameters(const DbEngineParameters& parameters)
 {
     if (!d)
     {
         d = new SimilarityDbAccessStaticPriv();
     }
 
     SimilarityDbAccessMutexLocker lock(d);
 
     if (d->parameters == parameters)
     {
         return;
     }
 
     if (d->backend && d->backend->isOpen())
     {
         d->backend->close();
     }
 
     // Kill the old database error handler
 
     if (d->backend)
     {
         d->backend->setDbEngineErrorHandler(nullptr);
     }
 
     d->parameters = parameters;
 
     if (!d->backend || !d->backend->isCompatible(parameters))
     {
         delete d->db;
         delete d->backend;
         d->backend = new SimilarityDbBackend(&d->lock);
         d->db      = new SimilarityDb(d->backend);
     }
 }
 
 bool SimilarityDbAccess::checkReadyForUse(InitializationObserver* const observer)
 {
     if (!DbEngineAccess::checkReadyForUse(d->lastError))
     {
         return false;
     }
 
     // Create an object with private shortcut constructor
 
     SimilarityDbAccess access(false);
 
     if (!d->backend)
     {
         qCWarning(DIGIKAM_SIMILARITYDB_LOG) << "Similarity database: no database backend available in checkReadyForUse. "
                                                 "Did you call setParameters before?";
         return false;
     }
 
     if (d->backend->isReady())
     {
         return true;
     }
 
     if (!d->backend->isOpen())
     {
         if (!d->backend->open(d->parameters))
         {
             access.setLastError(i18n("Error opening database backend.\n%1",
                                 d->backend->lastError()));
             return false;
         }
     }
 
     // Avoid endless loops (if called methods create new SimilarityDbAccess objects)
 
     d->initializing = true;
 
     // Update schema
 
     SimilarityDbSchemaUpdater updater(&access);
     updater.setObserver(observer);
 
     // Check or set WAL mode for SQLite database from DbEngineParameters
 
     d->backend->checkOrSetWALMode();
 
     if (!d->backend->initSchema(&updater))
     {
         qCWarning(DIGIKAM_SIMILARITYDB_LOG) << "Similarity database: cannot process schema initialization";
 
         d->initializing = false;
         return false;
     }
 
     d->initializing = false;
 
     return d->backend->isReady();
 }
 
 QString SimilarityDbAccess::lastError() const
 {
     return d->lastError;
 }
 
 void SimilarityDbAccess::setLastError(const QString& error)
 {
     d->lastError = error;
 }
 
 void SimilarityDbAccess::cleanUpDatabase()
 {
     if (d)
     {
         SimilarityDbAccessMutexLocker locker(d);
 
         if (d->backend)
         {
             d->backend->close();
             delete d->db;
             delete d->backend;
         }
     }
 
     delete d;
     d = nullptr;
 }
 
 } // namespace Digikam