From 60f7bb6a41cefa95ea775ee8346f3e7772ab4b85 Mon Sep 17 00:00:00 2001
From: Igor Kushnir <igorkuo@gmail.com>
Date: Wed, 7 Apr 2021 12:25:29 +0300
Subject: [PATCH 01/10] DataBaseManagement: remove dead code

---
 YACReaderLibrary/db/data_base_management.cpp | 15 ---------------
 YACReaderLibrary/db/data_base_management.h   |  6 +-----
 2 files changed, 1 insertion(+), 20 deletions(-)

diff --git a/YACReaderLibrary/db/data_base_management.cpp b/YACReaderLibrary/db/data_base_management.cpp
index 3e41d77df..dcd714bb5 100644
--- a/YACReaderLibrary/db/data_base_management.cpp
+++ b/YACReaderLibrary/db/data_base_management.cpp
@@ -44,21 +44,6 @@ static QString fields = "title ,"
 
                         "hash";
 
-DataBaseManagement::DataBaseManagement()
-    : QObject(), dataBasesList()
-{
-}
-
-/*TreeModel * DataBaseManagement::newTreeModel(QString path)
-{
-	//la consulta se ejecuta...
-	QSqlQuery selectQuery(loadDatabase(path));
-	selectQuery.setForwardOnly(true);
-	selectQuery.exec("select * from folder order by parentId,name");
-	//selectQuery.finish();
-	return new TreeModel(selectQuery);
-}*/
-
 QSqlDatabase DataBaseManagement::createDatabase(QString name, QString path)
 {
     return createDatabase(QDir::cleanPath(path) + "/" + name + ".ydb");
diff --git a/YACReaderLibrary/db/data_base_management.h b/YACReaderLibrary/db/data_base_management.h
index 3eac4a404..2375861a7 100644
--- a/YACReaderLibrary/db/data_base_management.h
+++ b/YACReaderLibrary/db/data_base_management.h
@@ -29,11 +29,9 @@ class ComicsInfoImporter : public QThread
     void run() override;
 };
 
-class DataBaseManagement : public QObject
+class DataBaseManagement
 {
-    Q_OBJECT
 private:
-    QList<QString> dataBasesList;
     static void bindString(const QString &name, const QSqlRecord &record, QSqlQuery &query);
     static void bindInt(const QString &name, const QSqlRecord &record, QSqlQuery &query);
     static void bindDouble(const QString &name, const QSqlRecord &record, QSqlQuery &query);
@@ -43,8 +41,6 @@ class DataBaseManagement : public QObject
     static bool addConstraint(const QString &tableName, const QString &constraint, const QSqlDatabase &db);
 
 public:
-    DataBaseManagement();
-    //TreeModel * newTreeModel(QString path);
     //crea una base de datos y todas sus tablas
     static QSqlDatabase createDatabase(QString name, QString path);
     static QSqlDatabase createDatabase(QString dest);

From b992d709e9264ebb11380e6c0d03c5116aa336ce Mon Sep 17 00:00:00 2001
From: Igor Kushnir <igorkuo@gmail.com>
Date: Wed, 7 Apr 2021 12:28:55 +0300
Subject: [PATCH 02/10] Remove some unused and add needed DB-related includes

Including only what is used should reduce compilation time.

The added includes were necessary to make the respective translation
units compile after a thorough cleanup of data_base_management.h
includes. This is how the complete include and forward-declaration
sections should look like in data_base_management.h:

'#'include <QThread> // (prevent '#' from starting a git comment line)

class QSqlDatabase;
class QSqlQuery;
class QSqlRecord;
class QString;
class QStringList;

Subsequently I had to partly restore the unnecessary includes by moving
them from data_base_management.cpp into the header due to the huge
number of compilation errors I am not prepared to deal with right now.
---
 YACReaderLibrary/db/comic_model.h                     |  1 -
 YACReaderLibrary/db/comic_query_result_processor.cpp  |  4 ++++
 YACReaderLibrary/db/data_base_management.cpp          |  5 ++++-
 YACReaderLibrary/db/data_base_management.h            | 10 ++++++----
 YACReaderLibrary/db/folder_model.h                    |  1 -
 YACReaderLibrary/db/folder_query_result_processor.cpp |  4 +++-
 YACReaderLibrary/db_helper.cpp                        |  1 +
 YACReaderLibrary/library_creator.cpp                  |  2 ++
 YACReaderLibrary/library_creator.h                    |  1 -
 YACReaderLibrary/library_window.cpp                   |  1 +
 YACReaderLibraryServer/libraries_updater.cpp          |  1 +
 11 files changed, 22 insertions(+), 9 deletions(-)

diff --git a/YACReaderLibrary/db/comic_model.h b/YACReaderLibrary/db/comic_model.h
index 4d9c05948..1203c02b5 100644
--- a/YACReaderLibrary/db/comic_model.h
+++ b/YACReaderLibrary/db/comic_model.h
@@ -5,7 +5,6 @@
 #include <QModelIndex>
 #include <QVariant>
 #include <QSqlQuery>
-#include <QSqlDatabase>
 #include <QUrl>
 
 #include "yacreader_global_gui.h"
diff --git a/YACReaderLibrary/db/comic_query_result_processor.cpp b/YACReaderLibrary/db/comic_query_result_processor.cpp
index d00ddebbe..d76c75a98 100644
--- a/YACReaderLibrary/db/comic_query_result_processor.cpp
+++ b/YACReaderLibrary/db/comic_query_result_processor.cpp
@@ -9,6 +9,10 @@
 
 #include "QsLog.h"
 
+#include <QSqlDatabase>
+#include <QSqlRecord>
+#include <QSqlQuery>
+
 QString getLastExecutedQuery(const QSqlQuery &query)
 {
     QString str = query.lastQuery();
diff --git a/YACReaderLibrary/db/data_base_management.cpp b/YACReaderLibrary/db/data_base_management.cpp
index dcd714bb5..31c541056 100644
--- a/YACReaderLibrary/db/data_base_management.cpp
+++ b/YACReaderLibrary/db/data_base_management.cpp
@@ -1,12 +1,15 @@
 #include "data_base_management.h"
 
-#include <QtCore>
 #include "library_creator.h"
 #include "check_new_version.h"
 #include "db_helper.h"
 
 #include "QsLog.h"
 
+#include <QDir>
+#include <QImageReader>
+#include <QList>
+
 static QString fields = "title ,"
 
                         "coverPage,"
diff --git a/YACReaderLibrary/db/data_base_management.h b/YACReaderLibrary/db/data_base_management.h
index 2375861a7..08371c873 100644
--- a/YACReaderLibrary/db/data_base_management.h
+++ b/YACReaderLibrary/db/data_base_management.h
@@ -1,11 +1,13 @@
 #ifndef __DATA_BASE_MANAGEMENT_H
 #define __DATA_BASE_MANAGEMENT_H
 
-#include <QtCore>
-#include <QtSql>
 #include <QSqlDatabase>
-
-#include "folder_model.h"
+#include <QSqlError>
+#include <QSqlQuery>
+#include <QSqlRecord>
+#include <QString>
+#include <QStringList>
+#include <QThread>
 
 class ComicsInfoExporter : public QThread
 {
diff --git a/YACReaderLibrary/db/folder_model.h b/YACReaderLibrary/db/folder_model.h
index 8eb19af17..fdd1cc2ae 100644
--- a/YACReaderLibrary/db/folder_model.h
+++ b/YACReaderLibrary/db/folder_model.h
@@ -6,7 +6,6 @@
 #include <QModelIndex>
 #include <QVariant>
 #include <QSqlQuery>
-#include <QSqlDatabase>
 
 #include "yacreader_global.h"
 #include "folder_query_result_processor.h"
diff --git a/YACReaderLibrary/db/folder_query_result_processor.cpp b/YACReaderLibrary/db/folder_query_result_processor.cpp
index 3cbde4547..fd7f41a09 100644
--- a/YACReaderLibrary/db/folder_query_result_processor.cpp
+++ b/YACReaderLibrary/db/folder_query_result_processor.cpp
@@ -9,8 +9,10 @@
 
 #include "QsLog.h"
 
-#include <QSqlQuery>
 #include <QSqlDatabase>
+#include <QSqlError>
+#include <QSqlQuery>
+#include <QSqlRecord>
 
 //Copy/pasted from "folder_model.cpp"
 #define ROOT 1
diff --git a/YACReaderLibrary/db_helper.cpp b/YACReaderLibrary/db_helper.cpp
index 3a0107560..b9f94662d 100644
--- a/YACReaderLibrary/db_helper.cpp
+++ b/YACReaderLibrary/db_helper.cpp
@@ -9,6 +9,7 @@
 #include <QCoreApplication>
 #include <QTextStream>
 #include <QSqlDatabase>
+#include <QSqlError>
 #include <QSqlRecord>
 #include <QSqlQuery>
 
diff --git a/YACReaderLibrary/library_creator.cpp b/YACReaderLibrary/library_creator.cpp
index fc4265134..b6d2c1377 100644
--- a/YACReaderLibrary/library_creator.cpp
+++ b/YACReaderLibrary/library_creator.cpp
@@ -3,6 +3,7 @@
 
 #include <QMutex>
 #include <QDebug>
+#include <QSqlError>
 #include <QSqlQuery>
 #include <QSqlRecord>
 #include <QCoreApplication>
@@ -11,6 +12,7 @@
 #include "data_base_management.h"
 #include "qnaturalsorting.h"
 #include "db_helper.h"
+#include "folder_model.h"
 
 #include "compressed_archive.h"
 #include "comic.h"
diff --git a/YACReaderLibrary/library_creator.h b/YACReaderLibrary/library_creator.h
index ccb27f244..3cc6a1f9f 100644
--- a/YACReaderLibrary/library_creator.h
+++ b/YACReaderLibrary/library_creator.h
@@ -12,7 +12,6 @@
 #include <QtGui>
 #include <QMutex>
 #include <QThread>
-#include <QSqlDatabase>
 #include <QModelIndex>
 
 #include "folder.h"
diff --git a/YACReaderLibrary/library_window.cpp b/YACReaderLibrary/library_window.cpp
index 1f68a6d68..ecc8fe9d0 100644
--- a/YACReaderLibrary/library_window.cpp
+++ b/YACReaderLibrary/library_window.cpp
@@ -1,6 +1,7 @@
 #include "library_window.h"
 #include "custom_widgets.h"
 #include "folder_item.h"
+#include "folder_model.h"
 
 #include <QHBoxLayout>
 #include <QSplitter>
diff --git a/YACReaderLibraryServer/libraries_updater.cpp b/YACReaderLibraryServer/libraries_updater.cpp
index 104341fcf..906197936 100644
--- a/YACReaderLibraryServer/libraries_updater.cpp
+++ b/YACReaderLibraryServer/libraries_updater.cpp
@@ -1,5 +1,6 @@
 #include "libraries_updater.h"
 
+#include "yacreader_global.h"
 #include "yacreader_libraries.h"
 #include "data_base_management.h"
 

From 80b533f1318114b967adec0032822e4186b16d5d Mon Sep 17 00:00:00 2001
From: Igor Kushnir <igorkuo@gmail.com>
Date: Wed, 7 Apr 2021 12:51:21 +0300
Subject: [PATCH 03/10] DataBaseManagement: take QString by const reference,
 not by value

Even an implicitly shared class is cheaper to pass by reference than by
value, as evidenced by Qt APIs themselves.
---
 YACReaderLibrary/db/data_base_management.cpp | 12 ++++++------
 YACReaderLibrary/db/data_base_management.h   | 12 ++++++------
 2 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/YACReaderLibrary/db/data_base_management.cpp b/YACReaderLibrary/db/data_base_management.cpp
index 31c541056..76553c888 100644
--- a/YACReaderLibrary/db/data_base_management.cpp
+++ b/YACReaderLibrary/db/data_base_management.cpp
@@ -47,12 +47,12 @@ static QString fields = "title ,"
 
                         "hash";
 
-QSqlDatabase DataBaseManagement::createDatabase(QString name, QString path)
+QSqlDatabase DataBaseManagement::createDatabase(const QString &name, const QString &path)
 {
     return createDatabase(QDir::cleanPath(path) + "/" + name + ".ydb");
 }
 
-QSqlDatabase DataBaseManagement::createDatabase(QString dest)
+QSqlDatabase DataBaseManagement::createDatabase(const QString &dest)
 {
     QString threadId = QString::number((long long)QThread::currentThreadId(), 16);
     QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE", dest + threadId);
@@ -78,7 +78,7 @@ QSqlDatabase DataBaseManagement::createDatabase(QString dest)
     return db;
 }
 
-QSqlDatabase DataBaseManagement::loadDatabase(QString path)
+QSqlDatabase DataBaseManagement::loadDatabase(const QString &path)
 {
     //TODO check path
     QString threadId = QString::number((long long)QThread::currentThreadId(), 16);
@@ -92,7 +92,7 @@ QSqlDatabase DataBaseManagement::loadDatabase(QString path)
     return db;
 }
 
-QSqlDatabase DataBaseManagement::loadDatabaseFromFile(QString filePath)
+QSqlDatabase DataBaseManagement::loadDatabaseFromFile(const QString &filePath)
 {
     //TODO check path
     QString threadId = QString::number((long long)QThread::currentThreadId(), 16);
@@ -307,7 +307,7 @@ bool DataBaseManagement::createV8Tables(QSqlDatabase &database)
     return success;
 }
 
-void DataBaseManagement::exportComicsInfo(QString source, QString dest)
+void DataBaseManagement::exportComicsInfo(const QString &source, const QString &dest)
 {
     QString connectionName = "";
     {
@@ -339,7 +339,7 @@ void DataBaseManagement::exportComicsInfo(QString source, QString dest)
     QSqlDatabase::removeDatabase(connectionName);
 }
 
-bool DataBaseManagement::importComicsInfo(QString source, QString dest)
+bool DataBaseManagement::importComicsInfo(const QString &source, const QString &dest)
 {
     QString error;
     QString driver;
diff --git a/YACReaderLibrary/db/data_base_management.h b/YACReaderLibrary/db/data_base_management.h
index 08371c873..b4c29241f 100644
--- a/YACReaderLibrary/db/data_base_management.h
+++ b/YACReaderLibrary/db/data_base_management.h
@@ -44,16 +44,16 @@ class DataBaseManagement
 
 public:
     //crea una base de datos y todas sus tablas
-    static QSqlDatabase createDatabase(QString name, QString path);
-    static QSqlDatabase createDatabase(QString dest);
+    static QSqlDatabase createDatabase(const QString &name, const QString &path);
+    static QSqlDatabase createDatabase(const QString &dest);
     //carga una base de datos desde la ruta path
-    static QSqlDatabase loadDatabase(QString path);
-    static QSqlDatabase loadDatabaseFromFile(QString path);
+    static QSqlDatabase loadDatabase(const QString &path);
+    static QSqlDatabase loadDatabaseFromFile(const QString &path);
     static bool createTables(QSqlDatabase &database);
     static bool createV8Tables(QSqlDatabase &database);
 
-    static void exportComicsInfo(QString source, QString dest);
-    static bool importComicsInfo(QString source, QString dest);
+    static void exportComicsInfo(const QString &source, const QString &dest);
+    static bool importComicsInfo(const QString &source, const QString &dest);
 
     static QString checkValidDB(const QString &fullPath); //retorna "" si la DB es inválida ó la versión si es válida.
     static int compareVersions(const QString &v1, const QString v2); //retorna <0 si v1 < v2, 0 si v1 = v2 y >0 si v1 > v2

From cffe11759f96e442f744ae4ffc81ccb3d89c4d25 Mon Sep 17 00:00:00 2001
From: Igor Kushnir <igorkuo@gmail.com>
Date: Wed, 7 Apr 2021 15:23:40 +0300
Subject: [PATCH 04/10] DBHelper::updateFolderTreeManga: reorder arguments for
 consistency

All other similar updating functions take db as the last argument.
---
 YACReaderLibrary/db/folder_model.cpp | 2 +-
 YACReaderLibrary/db_helper.cpp       | 4 ++--
 YACReaderLibrary/db_helper.h         | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/YACReaderLibrary/db/folder_model.cpp b/YACReaderLibrary/db/folder_model.cpp
index 35271125a..5a9616fb9 100644
--- a/YACReaderLibrary/db/folder_model.cpp
+++ b/YACReaderLibrary/db/folder_model.cpp
@@ -385,7 +385,7 @@ void FolderModel::updateFolderManga(const QModelIndexList &list, bool manga)
 
             setManga(item, manga);
 
-            DBHelper::updateFolderTreeManga(item->id, db, manga);
+            DBHelper::updateFolderTreeManga(item->id, manga, db);
         }
         db.commit();
         connectionName = db.connectionName();
diff --git a/YACReaderLibrary/db_helper.cpp b/YACReaderLibrary/db_helper.cpp
index b9f94662d..aac451916 100644
--- a/YACReaderLibrary/db_helper.cpp
+++ b/YACReaderLibrary/db_helper.cpp
@@ -1520,7 +1520,7 @@ QList<Label> DBHelper::getLabels(qulonglong libraryId)
     return labels;
 }
 
-void DBHelper::updateFolderTreeManga(qulonglong id, QSqlDatabase &db, bool manga)
+void DBHelper::updateFolderTreeManga(qulonglong id, bool manga, QSqlDatabase &db)
 {
     QSqlQuery updateFolderQuery(db);
     updateFolderQuery.prepare("UPDATE folder "
@@ -1546,7 +1546,7 @@ void DBHelper::updateFolderTreeManga(qulonglong id, QSqlDatabase &db, bool manga
     int childFolderIdPos = getSubFoldersQuery.record().indexOf("id");
 
     while (getSubFoldersQuery.next()) {
-        updateFolderTreeManga(getSubFoldersQuery.value(childFolderIdPos).toULongLong(), db, manga);
+        updateFolderTreeManga(getSubFoldersQuery.value(childFolderIdPos).toULongLong(), manga, db);
     }
 }
 
diff --git a/YACReaderLibrary/db_helper.h b/YACReaderLibrary/db_helper.h
index fa2a8960a..24745847c 100644
--- a/YACReaderLibrary/db_helper.h
+++ b/YACReaderLibrary/db_helper.h
@@ -86,7 +86,7 @@ class DBHelper
     static QList<LibraryItem *> getComicsFromParent(qulonglong parentId, QSqlDatabase &db, bool sort = true);
     static QList<Label> getLabels(qulonglong libraryId);
 
-    static void updateFolderTreeManga(qulonglong id, QSqlDatabase &db, bool manga);
+    static void updateFolderTreeManga(qulonglong id, bool manga, QSqlDatabase &db);
 
     //load
     static Folder loadFolder(qulonglong id, QSqlDatabase &db);

From 8b96fc04aac4b73505efa240846958f55e897762 Mon Sep 17 00:00:00 2001
From: Igor Kushnir <igorkuo@gmail.com>
Date: Thu, 8 Apr 2021 10:30:30 +0300
Subject: [PATCH 05/10] DBHelper: don't copy objects unnecessarily

Take QString arguments by value only if they are unconditionally moved
from.

Fix typos in DBHelper::reassignOrderTo* member function names.
---
 YACReaderLibrary/db/comic_model.cpp        |  6 ++---
 YACReaderLibrary/db/reading_list_model.cpp |  2 +-
 YACReaderLibrary/db_helper.cpp             | 26 +++++++++++-----------
 YACReaderLibrary/db_helper.h               | 12 +++++-----
 4 files changed, 23 insertions(+), 23 deletions(-)

diff --git a/YACReaderLibrary/db/comic_model.cpp b/YACReaderLibrary/db/comic_model.cpp
index da6c8a46a..bd53a1057 100644
--- a/YACReaderLibrary/db/comic_model.cpp
+++ b/YACReaderLibrary/db/comic_model.cpp
@@ -158,13 +158,13 @@ bool ComicModel::dropMimeData(const QMimeData *data, Qt::DropAction action, int
         QSqlDatabase db = DataBaseManagement::loadDatabase(_databasePath);
         switch (mode) {
         case Favorites:
-            DBHelper::reasignOrderToComicsInFavorites(allComicIds, db);
+            DBHelper::reassignOrderToComicsInFavorites(allComicIds, db);
             break;
         case Label:
-            DBHelper::reasignOrderToComicsInLabel(sourceId, allComicIds, db);
+            DBHelper::reassignOrderToComicsInLabel(sourceId, allComicIds, db);
             break;
         case ReadingList:
-            DBHelper::reasignOrderToComicsInReadingList(sourceId, allComicIds, db);
+            DBHelper::reassignOrderToComicsInReadingList(sourceId, allComicIds, db);
             break;
         default:
             break;
diff --git a/YACReaderLibrary/db/reading_list_model.cpp b/YACReaderLibrary/db/reading_list_model.cpp
index 5f3012572..a2ef671a0 100644
--- a/YACReaderLibrary/db/reading_list_model.cpp
+++ b/YACReaderLibrary/db/reading_list_model.cpp
@@ -711,7 +711,7 @@ void ReadingListModel::reorderingChildren(QList<ReadingListItem *> children)
     QString connectionName = "";
     {
         QSqlDatabase db = DataBaseManagement::loadDatabase(_databasePath);
-        DBHelper::reasignOrderToSublists(childrenIds, db);
+        DBHelper::reassignOrderToSublists(childrenIds, db);
         connectionName = db.connectionName();
     }
     QSqlDatabase::removeDatabase(connectionName);
diff --git a/YACReaderLibrary/db_helper.cpp b/YACReaderLibrary/db_helper.cpp
index aac451916..132c6cea8 100644
--- a/YACReaderLibrary/db_helper.cpp
+++ b/YACReaderLibrary/db_helper.cpp
@@ -14,7 +14,7 @@
 #include <QSqlQuery>
 
 #include <algorithm>
-#include <limits>
+#include <utility>
 
 #include "reading_list.h"
 #include "library_item.h"
@@ -1004,7 +1004,7 @@ void DBHelper::renameList(qulonglong id, const QString &name, QSqlDatabase &db)
     renameLabelQuery.exec();
 }
 
-void DBHelper::reasignOrderToSublists(QList<qulonglong> ids, QSqlDatabase &db)
+void DBHelper::reassignOrderToSublists(const QList<qulonglong> &ids, QSqlDatabase &db)
 {
     QSqlQuery updateOrdering(db);
     updateOrdering.prepare("UPDATE reading_list SET "
@@ -1012,7 +1012,7 @@ void DBHelper::reasignOrderToSublists(QList<qulonglong> ids, QSqlDatabase &db)
                            "WHERE id = :id");
     db.transaction();
     int order = 0;
-    foreach (qulonglong id, ids) {
+    for (auto id : ids) {
         updateOrdering.bindValue(":ordering", order++);
         updateOrdering.bindValue(":id", id);
         updateOrdering.exec();
@@ -1021,7 +1021,7 @@ void DBHelper::reasignOrderToSublists(QList<qulonglong> ids, QSqlDatabase &db)
     db.commit();
 }
 
-void DBHelper::reasignOrderToComicsInFavorites(QList<qulonglong> comicIds, QSqlDatabase &db)
+void DBHelper::reassignOrderToComicsInFavorites(const QList<qulonglong> &comicIds, QSqlDatabase &db)
 {
     QSqlQuery updateOrdering(db);
     updateOrdering.prepare("UPDATE comic_default_reading_list SET "
@@ -1029,7 +1029,7 @@ void DBHelper::reasignOrderToComicsInFavorites(QList<qulonglong> comicIds, QSqlD
                            "WHERE comic_id = :comic_id AND default_reading_list_id = 1");
     db.transaction();
     int order = 0;
-    foreach (qulonglong id, comicIds) {
+    for (auto id : comicIds) {
         updateOrdering.bindValue(":ordering", order++);
         updateOrdering.bindValue(":comic_id", id);
         updateOrdering.exec();
@@ -1038,7 +1038,7 @@ void DBHelper::reasignOrderToComicsInFavorites(QList<qulonglong> comicIds, QSqlD
     db.commit();
 }
 
-void DBHelper::reasignOrderToComicsInLabel(qulonglong labelId, QList<qulonglong> comicIds, QSqlDatabase &db)
+void DBHelper::reassignOrderToComicsInLabel(qulonglong labelId, const QList<qulonglong> &comicIds, QSqlDatabase &db)
 {
     QSqlQuery updateOrdering(db);
     updateOrdering.prepare("UPDATE comic_label SET "
@@ -1046,7 +1046,7 @@ void DBHelper::reasignOrderToComicsInLabel(qulonglong labelId, QList<qulonglong>
                            "WHERE comic_id = :comic_id AND label_id = :label_id");
     db.transaction();
     int order = 0;
-    foreach (qulonglong id, comicIds) {
+    for (auto id : comicIds) {
         updateOrdering.bindValue(":ordering", order++);
         updateOrdering.bindValue(":comic_id", id);
         updateOrdering.bindValue(":label_id", labelId);
@@ -1056,7 +1056,7 @@ void DBHelper::reasignOrderToComicsInLabel(qulonglong labelId, QList<qulonglong>
     db.commit();
 }
 
-void DBHelper::reasignOrderToComicsInReadingList(qulonglong readingListId, QList<qulonglong> comicIds, QSqlDatabase &db)
+void DBHelper::reassignOrderToComicsInReadingList(qulonglong readingListId, const QList<qulonglong> &comicIds, QSqlDatabase &db)
 {
     QSqlQuery updateOrdering(db);
     updateOrdering.prepare("UPDATE comic_reading_list SET "
@@ -1064,7 +1064,7 @@ void DBHelper::reasignOrderToComicsInReadingList(qulonglong readingListId, QList
                            "WHERE comic_id = :comic_id AND reading_list_id = :reading_list_id");
     db.transaction();
     int order = 0;
-    foreach (qulonglong id, comicIds) {
+    for (auto id : comicIds) {
         updateOrdering.bindValue(":ordering", order++);
         updateOrdering.bindValue(":comic_id", id);
         updateOrdering.bindValue(":reading_list_id", readingListId);
@@ -1670,13 +1670,13 @@ ComicDB DBHelper::loadComic(qulonglong id, QSqlDatabase &db)
     return comic;
 }
 
-ComicDB DBHelper::loadComic(QString cname, QString cpath, QString chash, QSqlDatabase &database)
+ComicDB DBHelper::loadComic(QString cname, QString cpath, const QString &chash, QSqlDatabase &database)
 {
     ComicDB comic;
 
     //comic.parentId = cparentId;
-    comic.name = cname;
-    comic.path = cpath;
+    comic.name = std::move(cname);
+    comic.path = std::move(cpath);
 
     comic.info = DBHelper::loadComicInfo(chash, database);
 
@@ -1690,7 +1690,7 @@ ComicDB DBHelper::loadComic(QString cname, QString cpath, QString chash, QSqlDat
     return comic;
 }
 
-ComicInfo DBHelper::loadComicInfo(QString hash, QSqlDatabase &db)
+ComicInfo DBHelper::loadComicInfo(const QString &hash, QSqlDatabase &db)
 {
     ComicInfo comicInfo;
 
diff --git a/YACReaderLibrary/db_helper.h b/YACReaderLibrary/db_helper.h
index 24745847c..26210214e 100644
--- a/YACReaderLibrary/db_helper.h
+++ b/YACReaderLibrary/db_helper.h
@@ -76,10 +76,10 @@ class DBHelper
     static void updateFromRemoteClientWithHash(const QList<ComicInfo> &comics);
     static void renameLabel(qulonglong id, const QString &name, QSqlDatabase &db);
     static void renameList(qulonglong id, const QString &name, QSqlDatabase &db);
-    static void reasignOrderToSublists(QList<qulonglong> ids, QSqlDatabase &db);
-    static void reasignOrderToComicsInFavorites(QList<qulonglong> comicIds, QSqlDatabase &db);
-    static void reasignOrderToComicsInLabel(qulonglong labelId, QList<qulonglong> comicIds, QSqlDatabase &db);
-    static void reasignOrderToComicsInReadingList(qulonglong readingListId, QList<qulonglong> comicIds, QSqlDatabase &db);
+    static void reassignOrderToSublists(const QList<qulonglong> &ids, QSqlDatabase &db);
+    static void reassignOrderToComicsInFavorites(const QList<qulonglong> &comicIds, QSqlDatabase &db);
+    static void reassignOrderToComicsInLabel(qulonglong labelId, const QList<qulonglong> &comicIds, QSqlDatabase &db);
+    static void reassignOrderToComicsInReadingList(qulonglong readingListId, const QList<qulonglong> &comicIds, QSqlDatabase &db);
 
     static QList<LibraryItem *> getFoldersFromParent(qulonglong parentId, QSqlDatabase &db, bool sort = true);
     static QList<ComicDB> getSortedComicsFromParent(qulonglong parentId, QSqlDatabase &db);
@@ -92,8 +92,8 @@ class DBHelper
     static Folder loadFolder(qulonglong id, QSqlDatabase &db);
     static Folder loadFolder(const QString &folderName, qulonglong parentId, QSqlDatabase &db);
     static ComicDB loadComic(qulonglong id, QSqlDatabase &db);
-    static ComicDB loadComic(QString cname, QString cpath, QString chash, QSqlDatabase &database);
-    static ComicInfo loadComicInfo(QString hash, QSqlDatabase &db);
+    static ComicDB loadComic(QString cname, QString cpath, const QString &chash, QSqlDatabase &database);
+    static ComicInfo loadComicInfo(const QString &hash, QSqlDatabase &db);
     static QList<QString> loadSubfoldersNames(qulonglong folderId, QSqlDatabase &db);
     //queries
     static bool isFavoriteComic(qulonglong id, QSqlDatabase &db);

From 4bc2ba473ed9af2c9a662734d15bec2552ec346f Mon Sep 17 00:00:00 2001
From: Igor Kushnir <igorkuo@gmail.com>
Date: Wed, 7 Apr 2021 12:56:32 +0300
Subject: [PATCH 06/10] Add two RAII classes: DatabaseHolder and DatabaseHelper

These classes will allow to improve exception and early-return safety as
well as simplify code that calls QSqlDatabase::removeDatabase().
---
 YACReaderLibrary/YACReaderLibrary.pro         |   2 +
 YACReaderLibrary/database_helper.cpp          |  33 +++++
 YACReaderLibrary/database_helper.h            | 124 ++++++++++++++++++
 .../YACReaderLibraryServer.pro                |   2 +
 4 files changed, 161 insertions(+)
 create mode 100644 YACReaderLibrary/database_helper.cpp
 create mode 100644 YACReaderLibrary/database_helper.h

diff --git a/YACReaderLibrary/YACReaderLibrary.pro b/YACReaderLibrary/YACReaderLibrary.pro
index 9a0e4bf29..b111749c6 100644
--- a/YACReaderLibrary/YACReaderLibrary.pro
+++ b/YACReaderLibrary/YACReaderLibrary.pro
@@ -92,6 +92,7 @@ HEADERS += comic_flow.h \
   import_comics_info_dialog.h \
   server_config_dialog.h \
   comic_flow_widget.h \
+  database_helper.h \
   db_helper.h \
   ./db/data_base_management.h \
   ./db/folder_item.h \
@@ -171,6 +172,7 @@ SOURCES += comic_flow.cpp \
     import_comics_info_dialog.cpp \
     server_config_dialog.cpp \
     comic_flow_widget.cpp \
+    database_helper.cpp \
     db_helper.cpp \
     ./db/data_base_management.cpp \
     ./db/folder_item.cpp \
diff --git a/YACReaderLibrary/database_helper.cpp b/YACReaderLibrary/database_helper.cpp
new file mode 100644
index 000000000..0a5844c29
--- /dev/null
+++ b/YACReaderLibrary/database_helper.cpp
@@ -0,0 +1,33 @@
+#include "database_helper.h"
+
+#include "data_base_management.h"
+
+#include "QsLog.h"
+
+using namespace YACReader;
+
+DatabaseHolder::DatabaseHolder(const QString &path)
+    : DatabaseHolder { DataBaseManagement::loadDatabase(path) }
+{
+}
+
+DatabaseHolder::DatabaseHolder(const QSqlDatabase &db)
+    : db { db }
+{
+    remover.setDb(this->db);
+}
+
+void DatabaseHolder::Remover::setDb(const QSqlDatabase &db)
+{
+    connectionName = db.connectionName();
+    Q_ASSERT(!connectionName.isEmpty());
+}
+
+DatabaseHolder::Remover::~Remover()
+{
+    if (connectionName.isEmpty()) {
+        QLOG_WARN() << "DatabaseHolder::Remover cannot remove a database: empty connection name.";
+        return;
+    }
+    QSqlDatabase::removeDatabase(connectionName);
+}
diff --git a/YACReaderLibrary/database_helper.h b/YACReaderLibrary/database_helper.h
new file mode 100644
index 000000000..5430dfd6b
--- /dev/null
+++ b/YACReaderLibrary/database_helper.h
@@ -0,0 +1,124 @@
+#ifndef DATABASE_HELPER_H
+#define DATABASE_HELPER_H
+
+#include "comic_db.h"
+#include "db_helper.h"
+#include "folder.h"
+
+#include <QList>
+#include <QSqlDatabase>
+#include <QString>
+
+#include <utility>
+
+namespace YACReader {
+
+//! A RAII class that adds or adopts a QSqlDatabase connection in its constructors
+//! and removes this connection via QSqlDatabase::removeDatabase() in the destructor.
+class DatabaseHolder
+{
+#if QT_VERSION >= QT_VERSION_CHECK(5, 13, 0)
+    Q_DISABLE_COPY_MOVE(DatabaseHolder)
+#else
+    Q_DISABLE_COPY(DatabaseHolder)
+#endif
+public:
+    explicit DatabaseHolder(const QString &path);
+    explicit DatabaseHolder(const QSqlDatabase &db);
+
+    QSqlDatabase &operator*() { return db; }
+    QSqlDatabase *operator->() { return &db; }
+
+private:
+    class Remover
+    {
+    public:
+        void setDb(const QSqlDatabase &db);
+        ~Remover();
+
+    private:
+        QString connectionName;
+    };
+
+    // The order of the data members is important: remover must be destroyed after
+    // db to avoid the Qt warning in log - "QSqlDatabasePrivate::removeDatabase:
+    // connection '<name>' is still in use, all queries will cease to work."
+    Remover remover;
+    QSqlDatabase db;
+};
+
+//! A wrapper around DatabaseHolder that makes access to the managed QSqlDatabase
+//! object a bit more verbose, but provides convenience forwarding functions for
+//! all DBHelper's member functions that take a QSqlDatabase & argument.
+class DatabaseHelper
+{
+public:
+    //! @note Access to DatabaseHolder(const QSqlDatabase &db) is intentionally
+    //! restricted to prevent its use by mistake. The QString constructor
+    //! overload is much more common and should be used most of the time. Use
+    //! DatabaseHolder directly if you need to load a database differently.
+    explicit DatabaseHelper(const QString &path)
+        : holder(path) { }
+
+    QSqlDatabase &db() { return *holder; }
+
+    // All public member functions below simply forward their arguments and db() to DBHelper.
+
+    //objects management
+    //deletes
+    void removeFromDB(LibraryItem *item) { DBHelper::removeFromDB(item, db()); }
+    void removeFromDB(Folder *folder) { DBHelper::removeFromDB(folder, db()); }
+    void removeFromDB(ComicDB *comic) { DBHelper::removeFromDB(comic, db()); }
+    void removeLabelFromDB(qulonglong id) { DBHelper::removeLabelFromDB(id, db()); }
+    void removeListFromDB(qulonglong id) { DBHelper::removeListFromDB(id, db()); }
+    //logic deletes
+    void deleteComicsFromFavorites(const QList<ComicDB> &comicsList) { DBHelper::deleteComicsFromFavorites(comicsList, db()); }
+    void deleteComicsFromLabel(const QList<ComicDB> &comicsList, qulonglong labelId) { DBHelper::deleteComicsFromLabel(comicsList, labelId, db()); }
+    void deleteComicsFromReadingList(const QList<ComicDB> &comicsList, qulonglong readingListId) { DBHelper::deleteComicsFromReadingList(comicsList, readingListId, db()); }
+    //inserts
+    qulonglong insert(Folder *folder) { return DBHelper::insert(folder, db()); }
+    qulonglong insert(ComicDB *comic) { return DBHelper::insert(comic, db()); }
+    qulonglong insertLabel(const QString &name, YACReader::LabelColors color) { return DBHelper::insertLabel(name, color, db()); }
+    qulonglong insertReadingList(const QString &name) { return DBHelper::insertReadingList(name, db()); }
+    qulonglong insertReadingSubList(const QString &name, qulonglong parentId, int ordering) { return DBHelper::insertReadingSubList(name, parentId, ordering, db()); }
+    void insertComicsInFavorites(const QList<ComicDB> &comicsList) { DBHelper::insertComicsInFavorites(comicsList, db()); }
+    void insertComicsInLabel(const QList<ComicDB> &comicsList, qulonglong labelId) { DBHelper::insertComicsInLabel(comicsList, labelId, db()); }
+    void insertComicsInReadingList(const QList<ComicDB> &comicsList, qulonglong readingListId) { DBHelper::insertComicsInReadingList(comicsList, readingListId, db()); }
+    //updates
+    void update(ComicDB *comics) { DBHelper::update(comics, db()); }
+    void update(ComicInfo *comicInfo) { DBHelper::update(comicInfo, db()); }
+    void updateRead(ComicInfo *comicInfo) { DBHelper::updateRead(comicInfo, db()); }
+    void update(const Folder &folder) { DBHelper::update(folder, db()); }
+    void updateChildrenInfo(const Folder &folder) { DBHelper::updateChildrenInfo(folder, db()); }
+    void updateChildrenInfo(qulonglong folderId) { DBHelper::updateChildrenInfo(folderId, db()); }
+    void updateChildrenInfo() { DBHelper::updateChildrenInfo(db()); }
+    void updateReadingRemoteProgress(const ComicInfo &comicInfo) { DBHelper::updateReadingRemoteProgress(comicInfo, db()); }
+    void renameLabel(qulonglong id, const QString &name) { DBHelper::renameLabel(id, name, db()); }
+    void renameList(qulonglong id, const QString &name) { DBHelper::renameList(id, name, db()); }
+    void reassignOrderToSublists(const QList<qulonglong> &ids) { DBHelper::reassignOrderToSublists(ids, db()); }
+    void reassignOrderToComicsInFavorites(const QList<qulonglong> &comicIds) { DBHelper::reassignOrderToComicsInFavorites(comicIds, db()); }
+    void reassignOrderToComicsInLabel(qulonglong labelId, const QList<qulonglong> &comicIds) { DBHelper::reassignOrderToComicsInLabel(labelId, comicIds, db()); }
+    void reassignOrderToComicsInReadingList(qulonglong readingListId, const QList<qulonglong> &comicIds) { DBHelper::reassignOrderToComicsInReadingList(readingListId, comicIds, db()); }
+
+    QList<LibraryItem *> getFoldersFromParent(qulonglong parentId, bool sort = true) { return DBHelper::getFoldersFromParent(parentId, db(), sort); }
+    QList<ComicDB> getSortedComicsFromParent(qulonglong parentId) { return DBHelper::getSortedComicsFromParent(parentId, db()); }
+    QList<LibraryItem *> getComicsFromParent(qulonglong parentId, bool sort = true) { return DBHelper::getComicsFromParent(parentId, db(), sort); }
+
+    void updateFolderTreeManga(qulonglong id, bool manga) { DBHelper::updateFolderTreeManga(id, manga, db()); }
+
+    //load
+    Folder loadFolder(qulonglong id) { return DBHelper::loadFolder(id, db()); }
+    Folder loadFolder(const QString &folderName, qulonglong parentId) { return DBHelper::loadFolder(folderName, parentId, db()); }
+    ComicDB loadComic(qulonglong id) { return DBHelper::loadComic(id, db()); }
+    ComicDB loadComic(QString cname, QString cpath, const QString &chash) { return DBHelper::loadComic(std::move(cname), std::move(cpath), chash, db()); }
+    ComicInfo loadComicInfo(const QString &hash) { return DBHelper::loadComicInfo(hash, db()); }
+    QList<QString> loadSubfoldersNames(qulonglong folderId) { return DBHelper::loadSubfoldersNames(folderId, db()); }
+    //queries
+    bool isFavoriteComic(qulonglong id) { return DBHelper::isFavoriteComic(id, db()); }
+
+private:
+    DatabaseHolder holder;
+};
+} // namespace YACReader
+
+#endif // DATABASE_HELPER_H
diff --git a/YACReaderLibraryServer/YACReaderLibraryServer.pro b/YACReaderLibraryServer/YACReaderLibraryServer.pro
index 78342492f..0041fe013 100644
--- a/YACReaderLibraryServer/YACReaderLibraryServer.pro
+++ b/YACReaderLibraryServer/YACReaderLibraryServer.pro
@@ -41,6 +41,7 @@ QT += core sql network
 HEADERS += ../YACReaderLibrary/library_creator.h \
            ../YACReaderLibrary/package_manager.h \
            ../YACReaderLibrary/bundle_creator.h \
+           ../YACReaderLibrary/database_helper.h \
            ../YACReaderLibrary/db_helper.h \
            ../YACReaderLibrary/db/data_base_management.h \
            ../YACReaderLibrary/db/reading_list.h \
@@ -64,6 +65,7 @@ HEADERS += ../YACReaderLibrary/library_creator.h \
 SOURCES += ../YACReaderLibrary/library_creator.cpp \
            ../YACReaderLibrary/package_manager.cpp \
            ../YACReaderLibrary/bundle_creator.cpp \
+           ../YACReaderLibrary/database_helper.cpp \
            ../YACReaderLibrary/db_helper.cpp \
            ../YACReaderLibrary/db/data_base_management.cpp \
            ../YACReaderLibrary/db/reading_list.cpp \

From 2a396a332b0398312b55ed341c59805fa510ae7b Mon Sep 17 00:00:00 2001
From: Igor Kushnir <igorkuo@gmail.com>
Date: Thu, 8 Apr 2021 14:49:35 +0300
Subject: [PATCH 07/10] DataBaseManagement::importComicsInfo: return void
 instead of false

The returned value is always the same and is not used by the caller.

Remove unused variables from this function.
---
 YACReaderLibrary/db/data_base_management.cpp | 8 +-------
 YACReaderLibrary/db/data_base_management.h   | 2 +-
 2 files changed, 2 insertions(+), 8 deletions(-)

diff --git a/YACReaderLibrary/db/data_base_management.cpp b/YACReaderLibrary/db/data_base_management.cpp
index 76553c888..ea84de77f 100644
--- a/YACReaderLibrary/db/data_base_management.cpp
+++ b/YACReaderLibrary/db/data_base_management.cpp
@@ -339,14 +339,10 @@ void DataBaseManagement::exportComicsInfo(const QString &source, const QString &
     QSqlDatabase::removeDatabase(connectionName);
 }
 
-bool DataBaseManagement::importComicsInfo(const QString &source, const QString &dest)
+void DataBaseManagement::importComicsInfo(const QString &source, const QString &dest)
 {
-    QString error;
-    QString driver;
     QStringList hashes;
 
-    bool b = false;
-
     QString sourceDBconnection = "";
     QString destDBconnection = "";
 
@@ -539,8 +535,6 @@ bool DataBaseManagement::importComicsInfo(const QString &source, const QString &
 
     QSqlDatabase::removeDatabase(sourceDBconnection);
     QSqlDatabase::removeDatabase(destDBconnection);
-
-    return b;
 }
 //TODO fix these bindings
 void DataBaseManagement::bindValuesFromRecord(const QSqlRecord &record, QSqlQuery &query)
diff --git a/YACReaderLibrary/db/data_base_management.h b/YACReaderLibrary/db/data_base_management.h
index b4c29241f..06ea19ef8 100644
--- a/YACReaderLibrary/db/data_base_management.h
+++ b/YACReaderLibrary/db/data_base_management.h
@@ -53,7 +53,7 @@ class DataBaseManagement
     static bool createV8Tables(QSqlDatabase &database);
 
     static void exportComicsInfo(const QString &source, const QString &dest);
-    static bool importComicsInfo(const QString &source, const QString &dest);
+    static void importComicsInfo(const QString &source, const QString &dest);
 
     static QString checkValidDB(const QString &fullPath); //retorna "" si la DB es inválida ó la versión si es válida.
     static int compareVersions(const QString &v1, const QString v2); //retorna <0 si v1 < v2, 0 si v1 = v2 y >0 si v1 > v2

From 981989472dd62e345f5b83a61bd23c14170941bf Mon Sep 17 00:00:00 2001
From: Igor Kushnir <igorkuo@gmail.com>
Date: Thu, 8 Apr 2021 14:52:44 +0300
Subject: [PATCH 08/10] DataBaseManagement: use DatabaseHolder

DatabaseHolder is preferable to DatabaseHelper here for these reasons:
1. DataBaseManagement uses DBHelper only once, so DatabaseHelper's
advantage is tiny here.
2. DataBaseManagement uses the wrapped QSqlDatabase object a lot.
DatabaseHolder's operators make these uses convenient and less verbose.
3. In YACReader code a QSqlDatabase object is almost always obtained via
DataBaseManagement::loadDatabase(). DatabaseHelper provides only one
constructor that adds a QSqlDatabase connection in this way to prevent
usage mistakes. By contrast, DataBaseManagement always adds QSqlDatabase
connections in other ways, so DatabaseHelper cannot be used as is.
---
 YACReaderLibrary/db/data_base_management.cpp | 616 +++++++++----------
 1 file changed, 293 insertions(+), 323 deletions(-)

diff --git a/YACReaderLibrary/db/data_base_management.cpp b/YACReaderLibrary/db/data_base_management.cpp
index ea84de77f..f93f773fe 100644
--- a/YACReaderLibrary/db/data_base_management.cpp
+++ b/YACReaderLibrary/db/data_base_management.cpp
@@ -2,6 +2,7 @@
 
 #include "library_creator.h"
 #include "check_new_version.h"
+#include "database_helper.h"
 #include "db_helper.h"
 
 #include "QsLog.h"
@@ -309,232 +310,216 @@ bool DataBaseManagement::createV8Tables(QSqlDatabase &database)
 
 void DataBaseManagement::exportComicsInfo(const QString &source, const QString &dest)
 {
-    QString connectionName = "";
-    {
-        QSqlDatabase destDB = loadDatabaseFromFile(dest);
-
-        QSqlQuery attach(destDB);
-        attach.prepare("ATTACH DATABASE '" + QDir().toNativeSeparators(dest) + "' AS dest;");
-        attach.exec();
+    YACReader::DatabaseHolder destDB(loadDatabaseFromFile(dest));
 
-        QSqlQuery attach2(destDB);
-        attach2.prepare("ATTACH DATABASE '" + QDir().toNativeSeparators(source) + "' AS source;");
-        attach2.exec();
+    QSqlQuery attach(*destDB);
+    attach.prepare("ATTACH DATABASE '" + QDir().toNativeSeparators(dest) + "' AS dest;");
+    attach.exec();
 
-        QSqlQuery queryDBInfo(destDB);
-        queryDBInfo.prepare("CREATE TABLE dest.db_info (version TEXT NOT NULL)");
-        queryDBInfo.exec();
+    QSqlQuery attach2(*destDB);
+    attach2.prepare("ATTACH DATABASE '" + QDir().toNativeSeparators(source) + "' AS source;");
+    attach2.exec();
 
-        QSqlQuery query("INSERT INTO dest.db_info (version) "
-                        "VALUES ('" VERSION "')",
-                        destDB);
+    QSqlQuery queryDBInfo(*destDB);
+    queryDBInfo.prepare("CREATE TABLE dest.db_info (version TEXT NOT NULL)");
+    queryDBInfo.exec();
 
-        QSqlQuery exportData(destDB);
-        exportData.prepare("create table dest.comic_info as select " + fields +
-                           " from source.comic_info where source.comic_info.edited = 1");
-        exportData.exec();
-        connectionName = destDB.connectionName();
-    }
+    QSqlQuery query("INSERT INTO dest.db_info (version) "
+                    "VALUES ('" VERSION "')",
+                    *destDB);
 
-    QSqlDatabase::removeDatabase(connectionName);
+    QSqlQuery exportData(*destDB);
+    exportData.prepare("create table dest.comic_info as select " + fields +
+                       " from source.comic_info where source.comic_info.edited = 1");
+    exportData.exec();
 }
 
 void DataBaseManagement::importComicsInfo(const QString &source, const QString &dest)
 {
     QStringList hashes;
 
-    QString sourceDBconnection = "";
-    QString destDBconnection = "";
+    YACReader::DatabaseHolder sourceDB(loadDatabaseFromFile(source));
+    YACReader::DatabaseHolder destDB(loadDatabaseFromFile(dest));
 
-    {
-        QSqlDatabase sourceDB = loadDatabaseFromFile(source);
-        QSqlDatabase destDB = loadDatabaseFromFile(dest);
-
-        QSqlQuery pragma("PRAGMA synchronous=OFF", destDB);
+    QSqlQuery pragma("PRAGMA synchronous=OFF", *destDB);
 
-        QSqlQuery newInfo(sourceDB);
-        newInfo.prepare("SELECT * FROM comic_info");
-        newInfo.exec();
-        destDB.transaction();
-        int cp;
-        while (newInfo.next()) //cada tupla deberá ser insertada o actualizada
-        {
-            QSqlQuery update(destDB);
-            update.prepare("UPDATE comic_info SET "
-                           "title = :title,"
-
-                           "coverPage = :coverPage,"
-                           "numPages = :numPages,"
-
-                           "number = :number,"
-                           "isBis = :isBis,"
-                           "count = :count,"
-
-                           "volume = :volume,"
-                           "storyArc = :storyArc,"
-                           "arcNumber = :arcNumber,"
-                           "arcCount = :arcCount,"
-
-                           "genere = :genere,"
-
-                           "writer = :writer,"
-                           "penciller = :penciller,"
-                           "inker = :inker,"
-                           "colorist = :colorist,"
-                           "letterer = :letterer,"
-                           "coverArtist = :coverArtist,"
-
-                           "date = :date,"
-                           "publisher = :publisher,"
-                           "format = :format,"
-                           "color = :color,"
-                           "ageRating = :ageRating,"
-                           "manga = :manga"
-
-                           "synopsis = :synopsis,"
-                           "characters = :characters,"
-                           "notes = :notes,"
-
-                           "edited = :edited,"
-
-                           "comicVineID = :comicVineID,"
-
-                           "lastTimeOpened = :lastTimeOpened,"
-
-                           "coverSizeRatio = :coverSizeRatio,"
-                           "originalCoverSize = :originalCoverSize"
-
-                           " WHERE hash = :hash ");
-
-            QSqlQuery insert(destDB);
-            insert.prepare("INSERT INTO comic_info "
-                           "(title,"
-                           "coverPage,"
-                           "numPages,"
-                           "number,"
-                           "isBis,"
-                           "count,"
-                           "volume,"
-                           "storyArc,"
-                           "arcNumber,"
-                           "arcCount,"
-                           "genere,"
-                           "writer,"
-                           "penciller,"
-                           "inker,"
-                           "colorist,"
-                           "letterer,"
-                           "coverArtist,"
-                           "date,"
-                           "publisher,"
-                           "format,"
-                           "color,"
-                           "ageRating,"
-                           "synopsis,"
-                           "characters,"
-                           "notes,"
-                           "read,"
-                           "edited,"
-                           "comicVineID,"
-                           "lastTimeOpened,"
-                           "coverSizeRatio,"
-                           "hash)"
-
-                           "VALUES (:title,"
-                           ":coverPage,"
-                           ":numPages,"
-                           ":number,"
-                           ":isBis,"
-                           ":count,"
-
-                           ":volume,"
-                           ":storyArc,"
-                           ":arcNumber,"
-                           ":arcCount,"
-
-                           ":genere,"
-
-                           ":writer,"
-                           ":penciller,"
-                           ":inker,"
-                           ":colorist,"
-                           ":letterer,"
-                           ":coverArtist,"
-
-                           ":date,"
-                           ":publisher,"
-                           ":format,"
-                           ":color,"
-                           ":ageRating,"
-                           ":manga,"
-
-                           ":synopsis,"
-                           ":characters,"
-                           ":notes,"
-
-                           ":read,"
-                           ":edited,"
-                           ":comicVineID,"
-
-                           ":lastTimeOpened,"
-
-                           ":coverSizeRatio,"
-                           ":originalCoverSize,"
-
-                           ":hash )");
-
-            QSqlRecord record = newInfo.record();
-            cp = record.value("coverPage").toInt();
-            if (cp > 1) {
-                QSqlQuery checkCoverPage(destDB);
-                checkCoverPage.prepare("SELECT coverPage FROM comic_info where hash = :hash");
-                checkCoverPage.bindValue(":hash", record.value("hash").toString());
-                checkCoverPage.exec();
-                bool extract = false;
-                if (checkCoverPage.next()) {
-                    extract = checkCoverPage.record().value("coverPage").toInt() != cp;
-                }
-                if (extract)
-                    hashes.append(record.value("hash").toString());
+    QSqlQuery newInfo(*sourceDB);
+    newInfo.prepare("SELECT * FROM comic_info");
+    newInfo.exec();
+    destDB->transaction();
+    int cp;
+    while (newInfo.next()) //cada tupla deberá ser insertada o actualizada
+    {
+        QSqlQuery update(*destDB);
+        update.prepare("UPDATE comic_info SET "
+                       "title = :title,"
+
+                       "coverPage = :coverPage,"
+                       "numPages = :numPages,"
+
+                       "number = :number,"
+                       "isBis = :isBis,"
+                       "count = :count,"
+
+                       "volume = :volume,"
+                       "storyArc = :storyArc,"
+                       "arcNumber = :arcNumber,"
+                       "arcCount = :arcCount,"
+
+                       "genere = :genere,"
+
+                       "writer = :writer,"
+                       "penciller = :penciller,"
+                       "inker = :inker,"
+                       "colorist = :colorist,"
+                       "letterer = :letterer,"
+                       "coverArtist = :coverArtist,"
+
+                       "date = :date,"
+                       "publisher = :publisher,"
+                       "format = :format,"
+                       "color = :color,"
+                       "ageRating = :ageRating,"
+                       "manga = :manga"
+
+                       "synopsis = :synopsis,"
+                       "characters = :characters,"
+                       "notes = :notes,"
+
+                       "edited = :edited,"
+
+                       "comicVineID = :comicVineID,"
+
+                       "lastTimeOpened = :lastTimeOpened,"
+
+                       "coverSizeRatio = :coverSizeRatio,"
+                       "originalCoverSize = :originalCoverSize"
+
+                       " WHERE hash = :hash ");
+
+        QSqlQuery insert(*destDB);
+        insert.prepare("INSERT INTO comic_info "
+                       "(title,"
+                       "coverPage,"
+                       "numPages,"
+                       "number,"
+                       "isBis,"
+                       "count,"
+                       "volume,"
+                       "storyArc,"
+                       "arcNumber,"
+                       "arcCount,"
+                       "genere,"
+                       "writer,"
+                       "penciller,"
+                       "inker,"
+                       "colorist,"
+                       "letterer,"
+                       "coverArtist,"
+                       "date,"
+                       "publisher,"
+                       "format,"
+                       "color,"
+                       "ageRating,"
+                       "synopsis,"
+                       "characters,"
+                       "notes,"
+                       "read,"
+                       "edited,"
+                       "comicVineID,"
+                       "lastTimeOpened,"
+                       "coverSizeRatio,"
+                       "hash)"
+
+                       "VALUES (:title,"
+                       ":coverPage,"
+                       ":numPages,"
+                       ":number,"
+                       ":isBis,"
+                       ":count,"
+
+                       ":volume,"
+                       ":storyArc,"
+                       ":arcNumber,"
+                       ":arcCount,"
+
+                       ":genere,"
+
+                       ":writer,"
+                       ":penciller,"
+                       ":inker,"
+                       ":colorist,"
+                       ":letterer,"
+                       ":coverArtist,"
+
+                       ":date,"
+                       ":publisher,"
+                       ":format,"
+                       ":color,"
+                       ":ageRating,"
+                       ":manga,"
+
+                       ":synopsis,"
+                       ":characters,"
+                       ":notes,"
+
+                       ":read,"
+                       ":edited,"
+                       ":comicVineID,"
+
+                       ":lastTimeOpened,"
+
+                       ":coverSizeRatio,"
+                       ":originalCoverSize,"
+
+                       ":hash )");
+
+        QSqlRecord record = newInfo.record();
+        cp = record.value("coverPage").toInt();
+        if (cp > 1) {
+            QSqlQuery checkCoverPage(*destDB);
+            checkCoverPage.prepare("SELECT coverPage FROM comic_info where hash = :hash");
+            checkCoverPage.bindValue(":hash", record.value("hash").toString());
+            checkCoverPage.exec();
+            bool extract = false;
+            if (checkCoverPage.next()) {
+                extract = checkCoverPage.record().value("coverPage").toInt() != cp;
             }
+            if (extract)
+                hashes.append(record.value("hash").toString());
+        }
 
-            bindValuesFromRecord(record, update);
+        bindValuesFromRecord(record, update);
 
-            update.bindValue(":edited", 1);
+        update.bindValue(":edited", 1);
 
-            update.exec();
+        update.exec();
 
-            if (update.numRowsAffected() == 0) {
+        if (update.numRowsAffected() == 0) {
 
-                bindValuesFromRecord(record, insert);
-                insert.bindValue(":edited", 1);
-                insert.bindValue(":read", 0);
+            bindValuesFromRecord(record, insert);
+            insert.bindValue(":edited", 1);
+            insert.bindValue(":read", 0);
 
-                insert.exec();
-            }
+            insert.exec();
         }
+    }
 
-        destDB.commit();
-        QString hash;
-        foreach (hash, hashes) {
-            QSqlQuery getComic(destDB);
-            getComic.prepare("SELECT c.path,ci.coverPage FROM comic c INNER JOIN comic_info ci ON (c.comicInfoId = ci.id) where ci.hash = :hash");
-            getComic.bindValue(":hash", hash);
-            getComic.exec();
-            if (getComic.next()) {
-                QString basePath = QString(dest).remove("/.yacreaderlibrary/library.ydb");
-                QString path = basePath + getComic.record().value("path").toString();
-                int coverPage = getComic.record().value("coverPage").toInt();
-                ThumbnailCreator tc(path, basePath + "/.yacreaderlibrary/covers/" + hash + ".jpg", coverPage);
-                tc.create();
-            }
+    destDB->commit();
+    QString hash;
+    foreach (hash, hashes) {
+        QSqlQuery getComic(*destDB);
+        getComic.prepare("SELECT c.path,ci.coverPage FROM comic c INNER JOIN comic_info ci ON (c.comicInfoId = ci.id) where ci.hash = :hash");
+        getComic.bindValue(":hash", hash);
+        getComic.exec();
+        if (getComic.next()) {
+            QString basePath = QString(dest).remove("/.yacreaderlibrary/library.ydb");
+            QString path = basePath + getComic.record().value("path").toString();
+            int coverPage = getComic.record().value("coverPage").toInt();
+            ThumbnailCreator tc(path, basePath + "/.yacreaderlibrary/covers/" + hash + ".jpg", coverPage);
+            tc.create();
         }
-        sourceDBconnection = sourceDB.connectionName();
-        destDBconnection = sourceDB.connectionName();
     }
-
-    QSqlDatabase::removeDatabase(sourceDBconnection);
-    QSqlDatabase::removeDatabase(destDBconnection);
 }
 //TODO fix these bindings
 void DataBaseManagement::bindValuesFromRecord(const QSqlRecord &record, QSqlQuery &query)
@@ -638,25 +623,15 @@ void DataBaseManagement::bindDouble(const QString &name, const QSqlRecord &recor
 
 QString DataBaseManagement::checkValidDB(const QString &fullPath)
 {
-    QString versionString = "";
-    QString connectionName = "";
-    {
-        QSqlDatabase db = loadDatabaseFromFile(fullPath);
-
-        if (db.isValid() && db.isOpen()) {
-            QSqlQuery version(db);
-            version.prepare("SELECT * FROM db_info");
-            version.exec();
-
-            if (version.next())
-                versionString = version.record().value("version").toString();
-        }
-        connectionName = db.connectionName();
+    YACReader::DatabaseHolder db(loadDatabaseFromFile(fullPath));
+    if (db->isValid() && db->isOpen()) {
+        QSqlQuery version(*db);
+        version.prepare("SELECT * FROM db_info");
+        version.exec();
+        if (version.next())
+            return version.record().value("version").toString();
     }
-
-    QSqlDatabase::removeDatabase(connectionName);
-
-    return versionString;
+    return QString();
 }
 
 int DataBaseManagement::compareVersions(const QString &v1, const QString v2)
@@ -710,135 +685,130 @@ bool DataBaseManagement::updateToCurrentVersion(const QString &path)
     if (compareVersions(DataBaseManagement::checkValidDB(fullPath), "9.8.0") < 0)
         pre9_8 = true;
 
-    QString connectionName = "";
     bool returnValue = false;
 
-    {
-        QSqlDatabase db = loadDatabaseFromFile(fullPath);
-        if (db.isValid() && db.isOpen()) {
-            QSqlQuery updateVersion(db);
-            updateVersion.prepare("UPDATE db_info SET "
-                                  "version = :version");
-            updateVersion.bindValue(":version", VERSION);
-            updateVersion.exec();
-
-            if (updateVersion.numRowsAffected() > 0)
-                returnValue = true;
-
-            if (pre7) //TODO: execute only if previous version was < 7.0
+    YACReader::DatabaseHolder db(loadDatabaseFromFile(fullPath));
+    if (db->isValid() && db->isOpen()) {
+        QSqlQuery updateVersion(*db);
+        updateVersion.prepare("UPDATE db_info SET "
+                              "version = :version");
+        updateVersion.bindValue(":version", VERSION);
+        updateVersion.exec();
+
+        if (updateVersion.numRowsAffected() > 0)
+            returnValue = true;
+
+        if (pre7) //TODO: execute only if previous version was < 7.0
+        {
+            //new 7.0 fields
+            QStringList columnDefs;
+            columnDefs << "hasBeenOpened BOOLEAN DEFAULT 0"
+                       << "rating INTEGER DEFAULT 0"
+                       << "currentPage INTEGER DEFAULT 1"
+                       << "bookmark1 INTEGER DEFAULT -1"
+                       << "bookmark2 INTEGER DEFAULT -1"
+                       << "bookmark3 INTEGER DEFAULT -1"
+                       << "brightness INTEGER DEFAULT -1"
+                       << "contrast INTEGER DEFAULT -1"
+                       << "gamma INTEGER DEFAULT -1";
+
+            bool successAddingColumns = addColumns("comic_info", columnDefs, *db);
+            returnValue = returnValue && successAddingColumns;
+        }
+        //TODO update hasBeenOpened value
+
+        if (pre7_1) {
             {
-                //new 7.0 fields
                 QStringList columnDefs;
-                columnDefs << "hasBeenOpened BOOLEAN DEFAULT 0"
-                           << "rating INTEGER DEFAULT 0"
-                           << "currentPage INTEGER DEFAULT 1"
-                           << "bookmark1 INTEGER DEFAULT -1"
-                           << "bookmark2 INTEGER DEFAULT -1"
-                           << "bookmark3 INTEGER DEFAULT -1"
-                           << "brightness INTEGER DEFAULT -1"
-                           << "contrast INTEGER DEFAULT -1"
-                           << "gamma INTEGER DEFAULT -1";
-
-                bool successAddingColumns = addColumns("comic_info", columnDefs, db);
+                columnDefs << "finished BOOLEAN DEFAULT 0"
+                           << "completed BOOLEAN DEFAULT 1";
+                bool successAddingColumns = addColumns("folder", columnDefs, *db);
                 returnValue = returnValue && successAddingColumns;
             }
-            //TODO update hasBeenOpened value
-
-            if (pre7_1) {
-                {
-                    QStringList columnDefs;
-                    columnDefs << "finished BOOLEAN DEFAULT 0"
-                               << "completed BOOLEAN DEFAULT 1";
-                    bool successAddingColumns = addColumns("folder", columnDefs, db);
-                    returnValue = returnValue && successAddingColumns;
-                }
 
-                { //comic_info
-                    QStringList columnDefs;
-                    columnDefs << "comicVineID TEXT DEFAULT NULL";
-                    bool successAddingColumns = addColumns("comic_info", columnDefs, db);
-                    returnValue = returnValue && successAddingColumns;
-                }
+            { //comic_info
+                QStringList columnDefs;
+                columnDefs << "comicVineID TEXT DEFAULT NULL";
+                bool successAddingColumns = addColumns("comic_info", columnDefs, *db);
+                returnValue = returnValue && successAddingColumns;
             }
+        }
 
-            if (pre8) {
-                bool successCreatingNewTables = createV8Tables(db);
-                returnValue = returnValue && successCreatingNewTables;
-            }
+        if (pre8) {
+            bool successCreatingNewTables = createV8Tables(*db);
+            returnValue = returnValue && successCreatingNewTables;
+        }
 
-            if (pre9_5) {
-                { //folder
-                    QStringList columnDefs;
-                    //a full library update is needed after updating the table
-                    columnDefs << "numChildren INTEGER";
-                    columnDefs << "firstChildHash TEXT";
-                    columnDefs << "customImage TEXT";
-                    bool successAddingColumns = addColumns("folder", columnDefs, db);
-                    returnValue = returnValue && successAddingColumns;
-                }
+        if (pre9_5) {
+            { //folder
+                QStringList columnDefs;
+                //a full library update is needed after updating the table
+                columnDefs << "numChildren INTEGER";
+                columnDefs << "firstChildHash TEXT";
+                columnDefs << "customImage TEXT";
+                bool successAddingColumns = addColumns("folder", columnDefs, *db);
+                returnValue = returnValue && successAddingColumns;
+            }
 
-                { //comic_info
-                    QStringList columnDefs;
-                    columnDefs << "lastTimeOpened INTEGER";
-                    columnDefs << "coverSizeRatio REAL";
-                    columnDefs << "originalCoverSize TEXT";
-                    bool successAddingColumns = addColumns("comic_info", columnDefs, db);
-                    returnValue = returnValue && successAddingColumns;
-
-                    QSqlQuery queryIndexLastTimeOpened(db);
-                    bool successCreatingIndex = queryIndexLastTimeOpened.exec("CREATE INDEX last_time_opened_index ON comic_info (lastTimeOpened)");
-                    returnValue = returnValue && successCreatingIndex;
-                }
+            { //comic_info
+                QStringList columnDefs;
+                columnDefs << "lastTimeOpened INTEGER";
+                columnDefs << "coverSizeRatio REAL";
+                columnDefs << "originalCoverSize TEXT";
+                bool successAddingColumns = addColumns("comic_info", columnDefs, *db);
+                returnValue = returnValue && successAddingColumns;
 
-                //update folders info
-                {
-                    DBHelper::updateChildrenInfo(db);
-                }
+                QSqlQuery queryIndexLastTimeOpened(*db);
+                bool successCreatingIndex = queryIndexLastTimeOpened.exec("CREATE INDEX last_time_opened_index ON comic_info (lastTimeOpened)");
+                returnValue = returnValue && successCreatingIndex;
+            }
 
-                {
-                    QSqlQuery selectQuery(db);
-                    selectQuery.prepare("SELECT id, hash FROM comic_info");
-                    selectQuery.exec();
+            //update folders info
+            {
+                DBHelper::updateChildrenInfo(*db);
+            }
 
-                    db.transaction();
+            {
+                QSqlQuery selectQuery(*db);
+                selectQuery.prepare("SELECT id, hash FROM comic_info");
+                selectQuery.exec();
 
-                    QSqlQuery updateCoverInfo(db);
-                    updateCoverInfo.prepare("UPDATE comic_info SET coverSizeRatio = :coverSizeRatio WHERE id = :id");
+                db->transaction();
 
-                    QImageReader thumbnail;
-                    while (selectQuery.next()) {
-                        thumbnail.setFileName(path % "/covers/" % selectQuery.value(1).toString() % ".jpg");
+                QSqlQuery updateCoverInfo(*db);
+                updateCoverInfo.prepare("UPDATE comic_info SET coverSizeRatio = :coverSizeRatio WHERE id = :id");
 
-                        float coverSizeRatio = static_cast<float>(thumbnail.size().width()) / thumbnail.size().height();
-                        updateCoverInfo.bindValue(":coverSizeRatio", coverSizeRatio);
-                        updateCoverInfo.bindValue(":id", selectQuery.value(0));
+                QImageReader thumbnail;
+                while (selectQuery.next()) {
+                    thumbnail.setFileName(path % "/covers/" % selectQuery.value(1).toString() % ".jpg");
 
-                        updateCoverInfo.exec();
-                    }
+                    float coverSizeRatio = static_cast<float>(thumbnail.size().width()) / thumbnail.size().height();
+                    updateCoverInfo.bindValue(":coverSizeRatio", coverSizeRatio);
+                    updateCoverInfo.bindValue(":id", selectQuery.value(0));
 
-                    db.commit();
+                    updateCoverInfo.exec();
                 }
+
+                db->commit();
             }
+        }
 
-            if (pre9_8) {
-                { //comic_info
-                    QStringList columnDefs;
-                    columnDefs << "manga BOOLEAN DEFAULT 0";
-                    bool successAddingColumns = addColumns("comic_info", columnDefs, db);
-                    returnValue = returnValue && successAddingColumns;
-                }
-                { //folder
-                    QStringList columnDefs;
-                    columnDefs << "manga BOOLEAN DEFAULT 0";
-                    bool successAddingColumns = addColumns("folder", columnDefs, db);
-                    returnValue = returnValue && successAddingColumns;
-                }
+        if (pre9_8) {
+            { //comic_info
+                QStringList columnDefs;
+                columnDefs << "manga BOOLEAN DEFAULT 0";
+                bool successAddingColumns = addColumns("comic_info", columnDefs, *db);
+                returnValue = returnValue && successAddingColumns;
+            }
+            { //folder
+                QStringList columnDefs;
+                columnDefs << "manga BOOLEAN DEFAULT 0";
+                bool successAddingColumns = addColumns("folder", columnDefs, *db);
+                returnValue = returnValue && successAddingColumns;
             }
         }
-        connectionName = db.connectionName();
     }
 
-    QSqlDatabase::removeDatabase(connectionName);
     return returnValue;
 }
 

From 2ae82de91205cc824f744503bbf7edc7ae2e1303 Mon Sep 17 00:00:00 2001
From: Igor Kushnir <igorkuo@gmail.com>
Date: Thu, 8 Apr 2021 16:06:59 +0300
Subject: [PATCH 09/10] ReadingListModel::setupReadingListsData: don't leak a
 DB connection

This change eliminates the following warning from the output of
YACReaderLibrary built in Debug mode:
  QSqlDatabasePrivate::addDatabase: duplicate connection name
  '/path/to/.yacreaderlibrary<thread id>', old connection removed.
---
 YACReaderLibrary/db/reading_list_model.cpp | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/YACReaderLibrary/db/reading_list_model.cpp b/YACReaderLibrary/db/reading_list_model.cpp
index a2ef671a0..a919a0a13 100644
--- a/YACReaderLibrary/db/reading_list_model.cpp
+++ b/YACReaderLibrary/db/reading_list_model.cpp
@@ -4,6 +4,7 @@
 
 #include "data_base_management.h"
 #include "qnaturalsorting.h"
+#include "database_helper.h"
 #include "db_helper.h"
 
 #include "QsLog.h"
@@ -352,20 +353,20 @@ void ReadingListModel::setupReadingListsData(QString path)
     cleanAll();
 
     _databasePath = path;
-    QSqlDatabase db = DataBaseManagement::loadDatabase(path);
+    YACReader::DatabaseHolder db(path);
 
     //setup special lists
-    specialLists = setupSpecialLists(db);
+    specialLists = setupSpecialLists(*db);
 
     //separator--------------------------------------------
 
     //setup labels
-    setupLabels(db);
+    setupLabels(*db);
 
     //separator--------------------------------------------
 
     //setup reading list
-    setupReadingLists(db);
+    setupReadingLists(*db);
 
     endResetModel();
 }

From e014662856fd7513ce29665a063a96cb07a01976 Mon Sep 17 00:00:00 2001
From: Igor Kushnir <igorkuo@gmail.com>
Date: Thu, 8 Apr 2021 16:46:21 +0300
Subject: [PATCH 10/10] ReadingListModel: use DatabaseHelper in 3 places

This change shows how code is simplified by using DatabaseHelper. It
also allows to test DatabaseHelper. Eventually DatabaseHelper (or rarely
DatabaseHolder) should replace almost all explicit
QSqlDatabase::removeDatabase() calls.
---
 YACReaderLibrary/db/reading_list_model.cpp | 99 +++++++++-------------
 1 file changed, 42 insertions(+), 57 deletions(-)

diff --git a/YACReaderLibrary/db/reading_list_model.cpp b/YACReaderLibrary/db/reading_list_model.cpp
index a919a0a13..bcb989c46 100644
--- a/YACReaderLibrary/db/reading_list_model.cpp
+++ b/YACReaderLibrary/db/reading_list_model.cpp
@@ -477,65 +477,55 @@ void ReadingListModel::rename(const QModelIndex &mi, const QString &name)
 {
     if (!isEditable(mi))
         return;
-    QString connectionName = "";
-    {
-        QSqlDatabase db = DataBaseManagement::loadDatabase(_databasePath);
-
-        auto item = static_cast<ListItem *>(mi.internalPointer());
+    YACReader::DatabaseHelper dbh(_databasePath);
 
-        if (typeid(*item) == typeid(ReadingListItem)) {
-            auto rli = static_cast<ReadingListItem *>(item);
-            rli->setName(name);
-            DBHelper::renameList(item->getId(), name, db);
-
-            if (rli->parent->getId() != 0) {
-                //TODO
-                //move row depending on the name
-            } else
-                emit dataChanged(index(mi.row(), 0), index(mi.row(), 0));
-        } else if (typeid(*item) == typeid(LabelItem)) {
-            auto li = static_cast<LabelItem *>(item);
-            li->setName(name);
-            DBHelper::renameLabel(item->getId(), name, db);
+    auto item = static_cast<ListItem *>(mi.internalPointer());
+    if (typeid(*item) == typeid(ReadingListItem)) {
+        auto rli = static_cast<ReadingListItem *>(item);
+        rli->setName(name);
+        dbh.renameList(item->getId(), name);
+
+        if (rli->parent->getId() != 0) {
+            //TODO
+            //move row depending on the name
+        } else
             emit dataChanged(index(mi.row(), 0), index(mi.row(), 0));
-        }
-        connectionName = db.connectionName();
+    } else if (typeid(*item) == typeid(LabelItem)) {
+        auto li = static_cast<LabelItem *>(item);
+        li->setName(name);
+        dbh.renameLabel(item->getId(), name);
+        emit dataChanged(index(mi.row(), 0), index(mi.row(), 0));
     }
-    QSqlDatabase::removeDatabase(connectionName);
 }
 
 void ReadingListModel::deleteItem(const QModelIndex &mi)
 {
-    if (isEditable(mi)) {
-        QLOG_DEBUG() << "parent row :" << mi.parent().data() << "-" << mi.row();
-        beginRemoveRows(mi.parent(), mi.row(), mi.row());
-        QString connectionName = "";
-        {
-            QSqlDatabase db = DataBaseManagement::loadDatabase(_databasePath);
-
-            auto item = static_cast<ListItem *>(mi.internalPointer());
-
-            if (typeid(*item) == typeid(ReadingListItem)) {
-                auto rli = static_cast<ReadingListItem *>(item);
-                QLOG_DEBUG() << "num children : " << rli->parent->childCount();
-                rli->parent->removeChild(rli);
-                QLOG_DEBUG() << "num children : " << rli->parent->childCount();
-                DBHelper::removeListFromDB(item->getId(), db);
-                if (rli->parent->getId() != 0) {
-                    reorderingChildren(rli->parent->children());
-                }
-                QLOG_DEBUG() << "num children : " << rli->parent->childCount();
-            } else if (typeid(*item) == typeid(LabelItem)) {
-                auto li = static_cast<LabelItem *>(item);
-                labels.removeOne(li);
-                DBHelper::removeLabelFromDB(item->getId(), db);
-            }
-            connectionName = db.connectionName();
-        }
-        QSqlDatabase::removeDatabase(connectionName);
+    if (!isEditable(mi))
+        return;
+
+    QLOG_DEBUG() << "parent row :" << mi.parent().data() << "-" << mi.row();
+    beginRemoveRows(mi.parent(), mi.row(), mi.row());
 
-        endRemoveRows();
+    YACReader::DatabaseHelper dbh(_databasePath);
+
+    auto item = static_cast<ListItem *>(mi.internalPointer());
+    if (typeid(*item) == typeid(ReadingListItem)) {
+        auto rli = static_cast<ReadingListItem *>(item);
+        QLOG_DEBUG() << "num children : " << rli->parent->childCount();
+        rli->parent->removeChild(rli);
+        QLOG_DEBUG() << "num children : " << rli->parent->childCount();
+        dbh.removeListFromDB(item->getId());
+        if (rli->parent->getId() != 0) {
+            reorderingChildren(rli->parent->children());
+        }
+        QLOG_DEBUG() << "num children : " << rli->parent->childCount();
+    } else if (typeid(*item) == typeid(LabelItem)) {
+        auto li = static_cast<LabelItem *>(item);
+        labels.removeOne(li);
+        dbh.removeLabelFromDB(item->getId());
     }
+
+    endRemoveRows();
 }
 
 const QList<LabelItem *> ReadingListModel::getLabels()
@@ -709,13 +699,8 @@ void ReadingListModel::reorderingChildren(QList<ReadingListItem *> children)
         item->setOrdering(i++);
         childrenIds << item->getId();
     }
-    QString connectionName = "";
-    {
-        QSqlDatabase db = DataBaseManagement::loadDatabase(_databasePath);
-        DBHelper::reassignOrderToSublists(childrenIds, db);
-        connectionName = db.connectionName();
-    }
-    QSqlDatabase::removeDatabase(connectionName);
+    YACReader::DatabaseHelper dbh(_databasePath);
+    dbh.reassignOrderToSublists(childrenIds);
 }
 
 bool ReadingListModel::rowIsSpecialList(int row, const QModelIndex &parent) const