diff --git a/gui/fielddelegate.h b/gui/fielddelegate.h
index afb0978..b90a3d5 100644
--- a/gui/fielddelegate.h
+++ b/gui/fielddelegate.h
@@ -9,7 +9,7 @@ class FieldDelegate : public QStyledItemDelegate {
 public:
     FieldDelegate(QObject *parent = nullptr);
 
-    void setEditorData(QWidget *editor, const QModelIndex &index) const;
+    void setEditorData(QWidget *editor, const QModelIndex &index) const override;
 };
 
 } // namespace QtGui
diff --git a/gui/mainwindow.cpp b/gui/mainwindow.cpp
index 8e4a78d..5ebf07c 100644
--- a/gui/mainwindow.cpp
+++ b/gui/mainwindow.cpp
@@ -440,13 +440,11 @@ bool MainWindow::openFile(const QString &path, bool readOnly)
     }
 
     // warn before loading a very big file
-    if (m_file.size() > 10485760) {
-        if (QMessageBox::warning(this, QApplication::applicationName(),
+    if (m_file.size() > 10485760 && QMessageBox::warning(this, QApplication::applicationName(),
                 tr("The file you want to load seems to be very big. Do you really want to open it?"), QMessageBox::Yes, QMessageBox::No)
             == QMessageBox::No) {
-            m_file.clear();
-            return false;
-        }
+        m_file.clear();
+        return false;
     }
 
     // ask for a password if required
@@ -488,18 +486,17 @@ bool MainWindow::openFile(const QString &path, bool readOnly)
     }
 
     // show a message in the error case
-    if (!msg.isEmpty()) {
-        m_file.clear();
-        m_ui->statusBar->showMessage(msg, 5000);
-        if (QMessageBox::critical(this, QApplication::applicationName(), msg, QMessageBox::Cancel, QMessageBox::Retry) == QMessageBox::Retry) {
-            return openFile(path, readOnly); // retry
-        } else {
-            return false;
-        }
-    } else {
+    if (msg.isEmpty()) {
         // show contents
         return showFile();
     }
+    m_file.clear();
+    m_ui->statusBar->showMessage(msg, 5000);
+    if (QMessageBox::critical(this, QApplication::applicationName(), msg, QMessageBox::Cancel, QMessageBox::Retry) == QMessageBox::Retry) {
+        return openFile(path, readOnly); // retry
+    } else {
+        return false;
+    }
 }
 
 /*!
@@ -618,7 +615,7 @@ void MainWindow::updateWindowTitle()
 void MainWindow::applyDefaultExpanding(const QModelIndex &parent)
 {
     for (int row = 0, rows = m_entryFilterModel->rowCount(parent); row < rows; ++row) {
-        QModelIndex index = m_entryFilterModel->index(row, 0, parent);
+        const QModelIndex index = m_entryFilterModel->index(row, 0, parent);
         if (!index.isValid()) {
             return;
         }
@@ -735,7 +732,7 @@ bool MainWindow::askForCreatingFile()
 
 /*!
  * \brief Shows an warning if no file is opened.
- * \retruns Returns whether the warning has been shown.
+ * \returns Returns whether the warning has been shown.
  */
 bool MainWindow::showNoFileOpened()
 {
@@ -748,7 +745,7 @@ bool MainWindow::showNoFileOpened()
 
 /*!
  * \brief Shows an warning if no account is selected.
- * \retruns Returns whether the warning has been shown.
+ * \returns Returns whether the warning has been shown.
  */
 bool MainWindow::showNoAccount()
 {
@@ -821,10 +818,8 @@ bool MainWindow::saveFile()
                 return false;
             }
         }
-    } else {
-        if (!askForCreatingFile()) {
-            return false;
-        }
+    } else if (!askForCreatingFile()) {
+        return false;
     }
 
     // ask for a password if none is set
@@ -858,16 +853,15 @@ bool MainWindow::saveFile()
         m_ui->statusBar->showMessage(msg, 5000);
         QMessageBox::critical(this, QApplication::applicationName(), msg);
         return false;
-    } else {
-        if (m_readOnly || m_somethingChanged) {
-            m_readOnly = false;
-            m_somethingChanged = false;
-            updateWindowTitle();
-        }
-        m_recentMgr->addEntry(QString::fromStdString(m_file.path()));
-        m_ui->statusBar->showMessage(tr("The password list has been saved."), 5000);
-        return true;
     }
+    if (m_readOnly || m_somethingChanged) {
+        m_readOnly = false;
+        m_somethingChanged = false;
+        updateWindowTitle();
+    }
+    m_recentMgr->addEntry(QString::fromStdString(m_file.path()));
+    m_ui->statusBar->showMessage(tr("The password list has been saved."), 5000);
+    return true;
 }
 
 /*!
@@ -904,13 +898,14 @@ void MainWindow::showContainingDirectory()
 {
     if (showNoFileOpened()) {
         return;
-    } else if (m_file.path().empty()) {
+    }
+    if (m_file.path().empty()) {
         QMessageBox::warning(this, QApplication::applicationName(), tr("The currently opened file hasn't been saved yet."));
-    } else {
-        const QFileInfo file(QString::fromStdString(m_file.path()));
-        if (file.dir().exists()) {
-            DesktopUtils::openLocalFileOrDir(file.dir().absolutePath());
-        }
+        return;
+    }
+    const QFileInfo file(QString::fromStdString(m_file.path()));
+    if (file.dir().exists()) {
+        DesktopUtils::openLocalFileOrDir(file.dir().absolutePath());
     }
 }
 
@@ -941,30 +936,29 @@ void MainWindow::addEntry(EntryType type)
         return;
     }
     const QModelIndexList selectedIndexes = m_ui->treeView->selectionModel()->selectedRows(0);
-    if (selectedIndexes.size() == 1) {
-        const QModelIndex selected = m_entryFilterModel->mapToSource(selectedIndexes.at(0));
-        if (m_entryModel->isNode(selected)) {
-            bool result;
-            const QString text = QInputDialog::getText(this, type == EntryType::Account ? tr("Add account") : tr("Add category"),
-                tr("Enter the entry name"), QLineEdit::Normal, tr("new entry"), &result);
-            if (result) {
-                if (!text.isEmpty()) {
-                    int row = m_entryModel->rowCount(selected);
-                    m_entryModel->setInsertType(type);
-                    if (m_entryModel->insertRow(row, selected)) {
-                        m_entryModel->setData(m_entryModel->index(row, 0, selected), text, Qt::DisplayRole);
-                        setSomethingChanged(true);
-                    } else {
-                        QMessageBox::warning(this, QApplication::applicationName(), tr("Unable to create new entry."));
-                    }
-                } else {
-                    QMessageBox::warning(this, QApplication::applicationName(), tr("You didn't enter text."));
-                }
-            }
-            return;
-        }
+    const QModelIndex selected = selectedIndexes.size() == 1 ? m_entryFilterModel->mapToSource(selectedIndexes.at(0)) : QModelIndex();
+    if (!selected.isValid() || !m_entryModel->isNode(selected)) {
+        QMessageBox::warning(this, QApplication::applicationName(), tr("No node element selected."));
+        return;
     }
-    QMessageBox::warning(this, QApplication::applicationName(), tr("No node element selected."));
+    bool result;
+    const QString text = QInputDialog::getText(this, type == EntryType::Account ? tr("Add account") : tr("Add category"),
+        tr("Enter the entry name"), QLineEdit::Normal, tr("new entry"), &result);
+    if (!result) {
+        return;
+    }
+    if (text.isEmpty()) {
+        QMessageBox::warning(this, QApplication::applicationName(), tr("You didn't enter text."));
+        return;
+    }
+    int row = m_entryModel->rowCount(selected);
+    m_entryModel->setInsertType(type);
+    if (!m_entryModel->insertRow(row, selected)) {
+        QMessageBox::warning(this, QApplication::applicationName(), tr("Unable to create new entry."));
+        return;
+    }
+    m_entryModel->setData(m_entryModel->index(row, 0, selected), text, Qt::DisplayRole);
+    setSomethingChanged(true);
 }
 
 /*!
@@ -976,13 +970,13 @@ void MainWindow::removeEntry()
         return;
     }
     const QModelIndexList selectedIndexes = m_ui->treeView->selectionModel()->selectedRows(0);
-    if (selectedIndexes.size() == 1) {
-        const QModelIndex selected = m_entryFilterModel->mapToSource(selectedIndexes.at(0));
-        if (!m_entryModel->removeRow(selected.row(), selected.parent())) {
-            QMessageBox::warning(this, QApplication::applicationName(), tr("Unable to remove the entry."));
-        }
-    } else {
+    if (selectedIndexes.size() != 1) {
         QMessageBox::warning(this, QApplication::applicationName(), tr("No entry selected."));
+        return;
+    }
+    const QModelIndex selected = m_entryFilterModel->mapToSource(selectedIndexes.at(0));
+    if (!m_entryModel->removeRow(selected.row(), selected.parent())) {
+        QMessageBox::warning(this, QApplication::applicationName(), tr("Unable to remove the entry."));
     }
 }
 
@@ -1023,19 +1017,19 @@ void MainWindow::insertRow()
         return;
     }
     const QModelIndexList selectedIndexes = m_ui->tableView->selectionModel()->selectedIndexes();
-    if (selectedIndexes.size()) {
-        int row = m_fieldModel->rowCount();
-        for (const QModelIndex &index : selectedIndexes) {
-            if (index.row() < row) {
-                row = index.row();
-            }
-        }
-        if (row < m_fieldModel->rowCount() - 1) {
-            m_fieldModel->insertRow(row);
-        }
-    } else {
+    if (selectedIndexes.empty()) {
         QMessageBox::warning(
             this, windowTitle(), tr("A field has to be selected since new fields are always inserted before the currently selected field."));
+        return;
+    }
+    int row = m_fieldModel->rowCount();
+    for (const QModelIndex &index : selectedIndexes) {
+        if (index.row() < row) {
+            row = index.row();
+        }
+    }
+    if (row < m_fieldModel->rowCount() - 1) {
+        m_fieldModel->insertRow(row);
     }
 }
 
@@ -1052,14 +1046,14 @@ void MainWindow::removeRows()
     for (const QModelIndex &index : selectedIndexes) {
         rows << index.row();
     }
-    if (rows.size()) {
-        for (int i = m_fieldModel->rowCount() - 1; i >= 0; --i) {
-            if (rows.contains(i)) {
-                m_fieldModel->removeRow(i);
-            }
-        }
-    } else {
+    if (rows.empty()) {
         QMessageBox::warning(this, windowTitle(), tr("No fields have been removed since there are currently no fields selected."));
+        return;
+    }
+    for (int i = m_fieldModel->rowCount() - 1; i >= 0; --i) {
+        if (rows.contains(i)) {
+            m_fieldModel->removeRow(i);
+        }
     }
 }
 
@@ -1088,13 +1082,13 @@ void MainWindow::setFieldType(FieldType fieldType)
         return;
     }
     const QModelIndexList selectedIndexes = m_ui->tableView->selectionModel()->selectedIndexes();
-    if (!selectedIndexes.isEmpty()) {
-        const QVariant typeVariant(static_cast<int>(fieldType));
-        for (const QModelIndex &index : selectedIndexes) {
-            m_fieldModel->setData(index, typeVariant, FieldTypeRole);
-        }
-    } else {
+    if (selectedIndexes.isEmpty()) {
         QMessageBox::warning(this, windowTitle(), tr("No fields have been changed since there are currently no fields selected."));
+        return;
+    }
+    const QVariant typeVariant(static_cast<int>(fieldType));
+    for (const QModelIndex &index : selectedIndexes) {
+        m_fieldModel->setData(index, typeVariant, FieldTypeRole);
     }
 }
 
@@ -1154,28 +1148,29 @@ void MainWindow::showTreeViewContextMenu()
         return;
     }
     const QModelIndexList selectedIndexes = m_ui->treeView->selectionModel()->selectedRows(0);
-    if (selectedIndexes.size() == 1) {
-        QMenu contextMenu(this);
-        QModelIndex selected = m_entryFilterModel->mapToSource(selectedIndexes.at(0));
-        Entry *entry = m_entryModel->entry(selected);
-        if (entry->type() == EntryType::Node) {
-            contextMenu.addAction(QIcon::fromTheme(QStringLiteral("list-add")), tr("Add account"), this, &MainWindow::addAccount);
-            contextMenu.addAction(QIcon::fromTheme(QStringLiteral("list-add")), tr("Add category"), this, &MainWindow::addCategory);
-        }
-        contextMenu.addAction(QIcon::fromTheme(QStringLiteral("list-remove")), tr("Remove entry"), this, &MainWindow::removeEntry);
-        if (entry->type() == EntryType::Node) {
-            auto *nodeEntry = static_cast<NodeEntry *>(entry);
-            contextMenu.addSeparator();
-            auto *action = new QAction(&contextMenu);
-            action->setCheckable(true);
-            action->setText(tr("Expanded by default"));
-            action->setChecked(nodeEntry->isExpandedByDefault());
-            connect(action, &QAction::triggered,
-                std::bind(&EntryModel::setData, m_entryModel, std::cref(selected), QVariant(!nodeEntry->isExpandedByDefault()), DefaultExpandedRole));
-            contextMenu.addAction(action);
-        }
-        contextMenu.exec(QCursor::pos());
+    if (selectedIndexes.size() != 1) {
+        return;
     }
+    QMenu contextMenu(this);
+    const QModelIndex selected(m_entryFilterModel->mapToSource(selectedIndexes.at(0)));
+    const Entry *const entry = m_entryModel->entry(selected);
+    if (entry->type() == EntryType::Node) {
+        contextMenu.addAction(QIcon::fromTheme(QStringLiteral("list-add")), tr("Add account"), this, &MainWindow::addAccount);
+        contextMenu.addAction(QIcon::fromTheme(QStringLiteral("list-add")), tr("Add category"), this, &MainWindow::addCategory);
+    }
+    contextMenu.addAction(QIcon::fromTheme(QStringLiteral("list-remove")), tr("Remove entry"), this, &MainWindow::removeEntry);
+    if (entry->type() == EntryType::Node) {
+        const auto *const nodeEntry = static_cast<const NodeEntry *>(entry);
+        contextMenu.addSeparator();
+        auto *const action = new QAction(&contextMenu);
+        action->setCheckable(true);
+        action->setText(tr("Expanded by default"));
+        action->setChecked(nodeEntry->isExpandedByDefault());
+        connect(action, &QAction::triggered,
+            std::bind(&EntryModel::setData, m_entryModel, std::cref(selected), QVariant(!nodeEntry->isExpandedByDefault()), DefaultExpandedRole));
+        contextMenu.addAction(action);
+    }
+    contextMenu.exec(QCursor::pos());
 }
 
 /*!
diff --git a/gui/mainwindow.h b/gui/mainwindow.h
index c9b0b95..934f79c 100644
--- a/gui/mainwindow.h
+++ b/gui/mainwindow.h
@@ -49,7 +49,7 @@ class MainWindow : public QMainWindow {
 
 public:
     explicit MainWindow(QSettings &settings, Dialogs::QtSettings *qtSettings = nullptr, QWidget *parent = nullptr);
-    ~MainWindow();
+    ~MainWindow() override;
 
 public slots:
     // file management
@@ -71,9 +71,9 @@ public slots:
     void showUndoView();
 
 protected:
-    bool eventFilter(QObject *obj, QEvent *event);
-    void closeEvent(QCloseEvent *event);
-    void timerEvent(QTimerEvent *event);
+    bool eventFilter(QObject *obj, QEvent *event) override;
+    void closeEvent(QCloseEvent *event) override;
+    void timerEvent(QTimerEvent *event) override;
 
 private slots:
     // file management
diff --git a/gui/passwordgeneratordialog.cpp b/gui/passwordgeneratordialog.cpp
index af1f35b..5b680d8 100644
--- a/gui/passwordgeneratordialog.cpp
+++ b/gui/passwordgeneratordialog.cpp
@@ -70,7 +70,6 @@ PasswordGeneratorDialog::PasswordGeneratorDialog(QWidget *parent)
  */
 PasswordGeneratorDialog::~PasswordGeneratorDialog()
 {
-    delete m_ui;
 }
 
 /*!
diff --git a/gui/passwordgeneratordialog.h b/gui/passwordgeneratordialog.h
index 2e0633f..0c93ee4 100644
--- a/gui/passwordgeneratordialog.h
+++ b/gui/passwordgeneratordialog.h
@@ -6,6 +6,7 @@
 #include <QDialog>
 
 #include <vector>
+#include <memory>
 
 namespace QtGui {
 
@@ -18,7 +19,7 @@ class PasswordGeneratorDialog : public QDialog {
 
 public:
     explicit PasswordGeneratorDialog(QWidget *parent = nullptr);
-    ~PasswordGeneratorDialog();
+    ~PasswordGeneratorDialog() override;
 
 private Q_SLOTS:
     void generateNewPassword();
@@ -27,7 +28,7 @@ private Q_SLOTS:
     void copyPassword();
 
 private:
-    Ui::PasswordGeneratorDialog *m_ui;
+    std::unique_ptr<Ui::PasswordGeneratorDialog> m_ui;
     std::vector<char> m_charset;
     Util::OpenSslRandomDevice m_random;
 };
diff --git a/gui/stacksupport.h b/gui/stacksupport.h
index 41d96f9..844a4dd 100644
--- a/gui/stacksupport.h
+++ b/gui/stacksupport.h
@@ -37,15 +37,14 @@ inline QUndoStack *StackSupport::undoStack()
  */
 inline bool StackSupport::push(CustomUndoCommand *command)
 {
-    if (m_undoStack) {
-        if (command->isNoop()) {
-            return true; // doing nothing can never fail
-        } else {
-            m_undoStack->push(command);
-            return command->redoResult();
-        }
+    if (!m_undoStack) {
+        return false;
     }
-    return false;
+    if (command->isNoop()) {
+        return true; // doing nothing can never fail
+    }
+    m_undoStack->push(command);
+    return command->redoResult();
 }
 
 /*!
diff --git a/gui/undocommands.cpp b/gui/undocommands.cpp
index 7f77a9e..9620325 100644
--- a/gui/undocommands.cpp
+++ b/gui/undocommands.cpp
@@ -132,7 +132,7 @@ FieldModelInsertRowsCommand::FieldModelInsertRowsCommand(FieldModel *model, int
     , m_row(row)
     , m_count(count)
 {
-    setText(QApplication::translate("undocommands", "insertion of %1 row(s) before row %2", 0, count).arg(count).arg(row + 1));
+    setText(QApplication::translate("undocommands", "insertion of %1 row(s) before row %2", nullptr, count).arg(count).arg(row + 1));
 }
 
 bool FieldModelInsertRowsCommand::internalRedo()
@@ -163,9 +163,9 @@ FieldModelRemoveRowsCommand::FieldModelRemoveRowsCommand(FieldModel *model, int
     , m_count(count)
 {
     if (count == 1) {
-        setText(QApplication::translate("undocommands", "removal of row %1", 0, count).arg(row + 1));
+        setText(QApplication::translate("undocommands", "removal of row %1", nullptr, count).arg(row + 1));
     } else {
-        setText(QApplication::translate("undocommands", "removal of the rows %1 to %2", 0, count).arg(row + 1).arg(row + count));
+        setText(QApplication::translate("undocommands", "removal of the rows %1 to %2", nullptr, count).arg(row + 1).arg(row + count));
     }
 }
 
diff --git a/gui/undocommands.h b/gui/undocommands.h
index bcd240c..b200626 100644
--- a/gui/undocommands.h
+++ b/gui/undocommands.h
@@ -27,8 +27,8 @@ public:
     bool redoResult() const;
     bool undoResult() const;
     bool isNoop() const;
-    void redo();
-    void undo();
+    void redo() override;
+    void undo() override;
 
 protected:
     void setNoop(bool noop);
@@ -81,8 +81,8 @@ public:
     explicit FieldModelSetValueCommand(FieldModel *model, const QModelIndex &index, const QVariant &value, int role);
 
 protected:
-    bool internalRedo();
-    bool internalUndo();
+    bool internalRedo() override;
+    bool internalUndo() override;
 
 private:
     Io::AccountEntry *m_account;
@@ -99,8 +99,8 @@ public:
     explicit FieldModelInsertRowsCommand(FieldModel *model, int row, int count);
 
 protected:
-    bool internalRedo();
-    bool internalUndo();
+    bool internalRedo() override;
+    bool internalUndo() override;
 
 private:
     Io::AccountEntry *m_account;
@@ -114,8 +114,8 @@ public:
     explicit FieldModelRemoveRowsCommand(FieldModel *model, int row, int count);
 
 protected:
-    bool internalRedo();
-    bool internalUndo();
+    bool internalRedo() override;
+    bool internalUndo() override;
 
 private:
     Io::AccountEntry *m_account;
@@ -130,8 +130,8 @@ public:
     explicit EntryModelSetValueCommand(EntryModel *model, const QModelIndex &index, const QVariant &value, int role);
 
 protected:
-    bool internalRedo();
-    bool internalUndo();
+    bool internalRedo() override;
+    bool internalUndo() override;
 
 private:
     EntryModel *m_model;
@@ -143,12 +143,10 @@ private:
 
 class EntryModelModifyRowsCommand : public CustomUndoCommand {
 public:
-    ~EntryModelModifyRowsCommand();
+    ~EntryModelModifyRowsCommand() override;
 
 protected:
     explicit EntryModelModifyRowsCommand(EntryModel *model, int row, int count, const QModelIndex &parent);
-    bool internalRedo() = 0;
-    bool internalUndo() = 0;
     bool insert();
     bool remove();
     EntryModel *m_model;
@@ -163,8 +161,8 @@ public:
     explicit EntryModelInsertRowsCommand(EntryModel *model, int row, int count, const QModelIndex &parent);
 
 protected:
-    bool internalRedo();
-    bool internalUndo();
+    bool internalRedo() override;
+    bool internalUndo() override;
 };
 
 class EntryModelRemoveRowsCommand : public EntryModelModifyRowsCommand {
@@ -172,8 +170,8 @@ public:
     explicit EntryModelRemoveRowsCommand(EntryModel *model, int row, int count, const QModelIndex &parent);
 
 protected:
-    bool internalRedo();
-    bool internalUndo();
+    bool internalRedo() override;
+    bool internalUndo() override;
 };
 
 class EntryModelMoveRowsCommand : public CustomUndoCommand {
@@ -182,8 +180,8 @@ public:
         EntryModel *model, const QModelIndex &sourceParent, int sourceRow, int count, const QModelIndex &destinationParent, int destinationChild);
 
 protected:
-    bool internalRedo();
-    bool internalUndo();
+    bool internalRedo() override;
+    bool internalUndo() override;
 
 private:
     EntryModel *m_model;
diff --git a/model/entrymodel.cpp b/model/entrymodel.cpp
index d29cdba..d14844f 100644
--- a/model/entrymodel.cpp
+++ b/model/entrymodel.cpp
@@ -61,11 +61,7 @@ EntryModel::EntryModel(QUndoStack *undoStack, QObject *parent) :
  */
 Entry *EntryModel::entry(const QModelIndex &index)
 {
-    if(index.isValid()) {
-        return static_cast<Entry *>(index.internalPointer());
-    } else {
-        return nullptr;
-    }
+    return index.isValid() ? static_cast<Entry *>(index.internalPointer()) : nullptr;
 }
 
 /*!
@@ -78,24 +74,24 @@ Entry *EntryModel::entry(const QModelIndex &index)
  */
 QList<Entry *> EntryModel::takeEntries(int row, int count, const QModelIndex &parent)
 {
-    QList<Entry *> res;
-    if(Entry *parentEntry = entry(parent)) {
-        if(parentEntry->type() == EntryType::Node) {
-            NodeEntry *parentNodeEntry = static_cast<NodeEntry *>(parentEntry);
-            int lastIndex = row + count - 1;
-            const vector<Entry *> &children = parentNodeEntry->children();
-            if(lastIndex < 0 || static_cast<size_t>(lastIndex) >= children.size()) {
-                lastIndex = children.size() - 1;
-            }
-            beginRemoveRows(parent, row, lastIndex);
-            for(int index = lastIndex; index >= row; --index) {
-                Entry *child = children.at(index);
-                child->setParent(nullptr);
-                res << child;
-            }
-            endRemoveRows();
-        }
+    Entry *const parentEntry = entry(parent);
+    if(!parentEntry || parentEntry->type() != EntryType::Node) {
+        return QList<Entry *>();
     }
+    QList<Entry *> res;
+    NodeEntry *const parentNodeEntry = static_cast<NodeEntry *>(parentEntry);
+    int lastIndex = row + count - 1;
+    const vector<Entry *> &children = parentNodeEntry->children();
+    if(lastIndex < 0 || static_cast<size_t>(lastIndex) >= children.size()) {
+        lastIndex = children.size() - 1;
+    }
+    beginRemoveRows(parent, row, lastIndex);
+    for(int index = lastIndex; index >= row; --index) {
+        Entry *const child = children[index];
+        child->setParent(nullptr);
+        res << child;
+    }
+    endRemoveRows();
     return res;
 }
 
@@ -111,42 +107,45 @@ bool EntryModel::insertEntries(int row, const QModelIndex &parent, const QList<E
     if(entries.isEmpty()) {
         return true;
     }
-    if(Entry *parentEntry = entry(parent)) {
-        if(parentEntry->type() == EntryType::Node) {
-            NodeEntry *parentNodeEntry = static_cast<NodeEntry *>(parentEntry);
-            const vector<Entry *> &children = parentNodeEntry->children();
-            if(row < 0 || static_cast<size_t>(row) > children.size()) {
-                row = children.size();
-            }
-            beginInsertRows(parent, row, row + entries.size() - 1);
-            foreach(Entry *entry, entries) {
-                entry->setParent(parentNodeEntry, row);
-                ++row;
-            }
-            endInsertRows();
-            return true;
-        }
+    Entry *const parentEntry = entry(parent);
+    if(!parentEntry || parentEntry->type() != EntryType::Node) {
+        return false;
     }
-    return false;
+    NodeEntry *const parentNodeEntry = static_cast<NodeEntry *>(parentEntry);
+    const vector<Entry *> &children = parentNodeEntry->children();
+    if(row < 0 || static_cast<size_t>(row) > children.size()) {
+        row = children.size();
+    }
+    beginInsertRows(parent, row, row + entries.size() - 1);
+    for(Entry *const entry : entries) {
+        entry->setParent(parentNodeEntry, row);
+        ++row;
+    }
+    endInsertRows();
+    return true;
 }
 
 QModelIndex EntryModel::index(int row, int column, const QModelIndex &parent) const
 {
-    if(parent.isValid()) {
-        if(Entry *parentEntry = static_cast<Entry *>(parent.internalPointer())) {
-            switch(parentEntry->type()) {
-            case EntryType::Node: {
-                const std::vector<Entry *> &children = static_cast<NodeEntry *>(parentEntry)->children();
-                if(row >= 0 && static_cast<size_t>(row) < children.size()) {
-                    return createIndex(row, column, children.at(row));
-                }
-                break;
-            } case EntryType::Account:
-                ;
-            }
+    if(!parent.isValid()) {
+        if(m_rootEntry && row == 0) {
+            return createIndex(row, column, m_rootEntry);
         }
-    } else if(m_rootEntry && row == 0) {
-        return createIndex(row, column, m_rootEntry);
+        return QModelIndex();
+    }
+    const auto *const parentEntry = static_cast<const Entry *>(parent.internalPointer());
+    if(!parentEntry) {
+        return QModelIndex();
+    }
+    switch(parentEntry->type()) {
+    case EntryType::Node: {
+        const std::vector<Entry *> &children = static_cast<const NodeEntry *>(parentEntry)->children();
+        if(row >= 0 && static_cast<size_t>(row) < children.size()) {
+            return createIndex(row, column, children[static_cast<size_t>(row)]);
+        }
+        break;
+    } case EntryType::Account:
+        ;
     }
     return QModelIndex();
 }
@@ -166,29 +165,27 @@ QModelIndex EntryModel::index(Entry *entry) const
 
 QModelIndex EntryModel::parent(const QModelIndex &child) const
 {
-    if(child.isValid()) {
-        if(Entry *entry = static_cast<Entry *>(child.internalPointer())) {
-            NodeEntry *parent = entry->parent();
-            if(parent && (child.row() >= 0 && static_cast<size_t>(child.row()) < parent->children().size())) {
-                return createIndex(parent->index() > 0 ? parent->index() : 0, 0, parent);
-            }
-        }
+    if(!child.isValid()) {
+        return QModelIndex();
+    }
+    const auto *const entry = static_cast<Entry *>(child.internalPointer());
+    if(!entry) {
+        return QModelIndex();
+    }
+    NodeEntry *const parent = entry->parent();
+    if(parent && (child.row() >= 0 && static_cast<size_t>(child.row()) < parent->children().size())) {
+        return createIndex(parent->index() > 0 ? parent->index() : 0, 0, parent);
     }
     return QModelIndex();
 }
 
 bool EntryModel::hasChildren(const QModelIndex &parent) const
 {
-    if(parent.isValid()) {
-        if(Entry *entry = static_cast<Entry *>(parent.internalPointer())) {
-            if(entry->type() == EntryType::Node) {
-                return static_cast<NodeEntry *>(entry)->children().size();
-            }
-        }
-    } else {
+    if(!parent.isValid()) {
         return true;
     }
-    return false;
+    const auto *const entry = static_cast<Entry *>(parent.internalPointer());
+    return entry && entry->type() == EntryType::Node && !static_cast<const NodeEntry *>(entry)->children().empty();
 }
 
 /*!
@@ -197,63 +194,65 @@ bool EntryModel::hasChildren(const QModelIndex &parent) const
  */
 bool EntryModel::isNode(const QModelIndex &parent) const
 {
-    if(parent.isValid()) {
-        if(Entry *entry = static_cast<Entry *>(parent.internalPointer())) {
-            return entry->type() == EntryType::Node;
-        }
+    if(!parent.isValid()) {
+        return false;
     }
-    return false;
+    const auto *const entry = static_cast<const Entry *>(parent.internalPointer());
+    return entry && entry->type() == EntryType::Node;
 }
 
 QVariant EntryModel::data(const QModelIndex &index, int role) const
 {
-    if(index.isValid()) {
-        if(Entry *entry = static_cast<Entry *>(index.internalPointer())) {
-            switch(role) {
-            case Qt::DisplayRole:
-            case Qt::EditRole:
-                switch(index.column()) {
-                case 0:
-                    return QString::fromStdString(entry->label());
-                default:
-                    ;
-                }
-                break;
-            case Qt::DecorationRole:
-                if(index.column() == 0 && entry->type() == EntryType::Node) {
-                    static const QVariant folderIcon = QIcon::fromTheme(QStringLiteral("folder"));
-                    return folderIcon;
-                }
-                break;
-            case SerializedRole: {
-                    stringstream ss(stringstream::in | stringstream::out | stringstream::binary);
-                    ss.exceptions(std::stringstream::failbit | std::stringstream::badbit);
-                    try {
-                        entry->make(ss);
-                        string string = ss.str();
-                        return QByteArray(string.data(), string.size());
-                    } catch(...) {
-                        IoUtilities::catchIoFailure();
-                        return false;
-                    }
-                }
-                break;
-            case DefaultExpandedRole:
-                return entry->type() == EntryType::Node && static_cast<NodeEntry *>(entry)->isExpandedByDefault();
-            default:
-                ;
+    if(!index.isValid()) {
+        return QVariant();
+    }
+    const auto *const entry = static_cast<const Entry *>(index.internalPointer());
+    if(!entry) {
+        return QVariant();
+    }
+    switch(role) {
+    case Qt::DisplayRole:
+    case Qt::EditRole:
+        switch(index.column()) {
+        case 0:
+            return QString::fromStdString(entry->label());
+        default:
+            ;
+        }
+        break;
+    case Qt::DecorationRole:
+        if(index.column() == 0 && entry->type() == EntryType::Node) {
+            static const QVariant folderIcon = QIcon::fromTheme(QStringLiteral("folder"));
+            return folderIcon;
+        }
+        break;
+    case SerializedRole: {
+            stringstream ss(stringstream::in | stringstream::out | stringstream::binary);
+            ss.exceptions(std::stringstream::failbit | std::stringstream::badbit);
+            try {
+                entry->make(ss);
+                const auto str(ss.str());
+                return QByteArray(str.data(), str.size());
+            } catch(...) {
+                IoUtilities::catchIoFailure();
+                return false;
             }
         }
+        break;
+    case DefaultExpandedRole:
+        return entry->type() == EntryType::Node && static_cast<const NodeEntry *>(entry)->isExpandedByDefault();
+    default:
+        ;
     }
     return QVariant();
 }
 
 QMap<int, QVariant> EntryModel::itemData(const QModelIndex &index) const
 {
-    QMap<int, QVariant> roles;
-    roles.insert(Qt::DisplayRole, data(index, Qt::DisplayRole));
-    roles.insert(SerializedRole, data(index, SerializedRole));
-    return roles;
+    return QMap<int, QVariant>{
+        {Qt::DisplayRole, data(index, Qt::DisplayRole)},
+        {SerializedRole, data(index, SerializedRole)},
+    };
 }
 
 bool EntryModel::setData(const QModelIndex &index, const QVariant &value, int role)
@@ -263,60 +262,65 @@ bool EntryModel::setData(const QModelIndex &index, const QVariant &value, int ro
         return push(new EntryModelSetValueCommand(this, index, value, role));
     }
 #endif
-    if(index.isValid()) {
-        if(Entry *entry = static_cast<Entry *>(index.internalPointer())) {
-            switch(role) {
-            case Qt::DisplayRole:
-            case Qt::EditRole:
-                switch(index.column()) {
-                case 0:
-                    entry->setLabel(value.toString().toStdString());
-                    emit dataChanged(index, index, QVector<int>() << role);
-                    return true;
-                default:
-                    ;
-                }
+    if(!index.isValid()) {
+        return false;
+    }
+    auto *const entry = static_cast<Entry *>(index.internalPointer());
+    if(!entry) {
+        return false;
+    }
+    switch(role) {
+    case Qt::DisplayRole:
+    case Qt::EditRole:
+        switch(index.column()) {
+        case 0:
+            entry->setLabel(value.toString().toStdString());
+            emit dataChanged(index, index, QVector<int>() << role);
+            return true;
+        default:
+            ;
+        }
+        break;
+    case SerializedRole: {
+            NodeEntry *parent = entry->parent();
+            QModelIndex parentIndex = index.parent();
+            if(!parent || !parentIndex.isValid()) {
                 break;
-            case SerializedRole: {
-                    NodeEntry *parent = entry->parent();
-                    QModelIndex parentIndex = index.parent();
-                    if(parent && parentIndex.isValid()) {
-                        stringstream ss(stringstream::in | stringstream::out | stringstream::binary);
-                        ss.exceptions(std::stringstream::failbit | std::stringstream::badbit);
-                        QByteArray array = value.toByteArray();
-                        if(array.size()) {
-                            try {
-                                ss.write(array.data(), array.size());
-                                Entry *newEntry = Entry::parse(ss);
-                                int row = entry->index();
-                                beginRemoveRows(parentIndex, row, row);
-                                delete entry;
-                                endRemoveRows();
-                                beginInsertRows(parentIndex, row, row);
-                                newEntry->setParent(parent, row);
-                                endInsertRows();
-                                return true;
-                            } catch(...) {
-                                IoUtilities::catchIoFailure();
-                            }
-                        }
-                    }
-                }
+            }
+            stringstream ss(stringstream::in | stringstream::out | stringstream::binary);
+            ss.exceptions(std::stringstream::failbit | std::stringstream::badbit);
+            QByteArray array = value.toByteArray();
+            if(array.isEmpty()) {
                 break;
-            case DefaultExpandedRole:
-                switch(entry->type()) {
-                case EntryType::Account:
-                    return false;
-                case EntryType::Node:
-                    static_cast<NodeEntry *>(entry)->setExpandedByDefault(value.toBool());
-                    emit dataChanged(index, index, QVector<int>() << role);
-                    return true;
-                }
-                break;
-            default:
-                ;
+            }
+            try {
+                ss.write(array.data(), array.size());
+                Entry *newEntry = Entry::parse(ss);
+                int row = entry->index();
+                beginRemoveRows(parentIndex, row, row);
+                delete entry;
+                endRemoveRows();
+                beginInsertRows(parentIndex, row, row);
+                newEntry->setParent(parent, row);
+                endInsertRows();
+                return true;
+            } catch(...) {
+                IoUtilities::catchIoFailure();
             }
         }
+        break;
+    case DefaultExpandedRole:
+        switch(entry->type()) {
+        case EntryType::Account:
+            return false;
+        case EntryType::Node:
+            static_cast<NodeEntry *>(entry)->setExpandedByDefault(value.toBool());
+            emit dataChanged(index, index, QVector<int>() << role);
+            return true;
+        }
+        break;
+    default:
+        ;
     }
     return false;
 }
@@ -388,30 +392,30 @@ bool EntryModel::insertRows(int row, int count, const QModelIndex &parent)
         return push(new EntryModelInsertRowsCommand(this, row, count, parent));
     }
 #endif
-    if(parent.isValid()) {
-        if(Entry *parentEntry = static_cast<Entry *>(parent.internalPointer())) {
-            if(parentEntry->type() == EntryType::Node) {
-                beginInsertRows(parent, row, row + count - 1);
-                for(int end = row + count; row < end; ++row) {
-                    Entry *newEntry;
-                    switch(m_insertType) {
-                    case EntryType::Node:
-                        newEntry = new NodeEntry;
-                        break;
-                    case EntryType::Account:
-                        newEntry = new AccountEntry;
-                        break;
-                    default:
-                        return false; // should never be reached, just to suppress compiler warning
-                    }
-                    newEntry->setParent(static_cast<NodeEntry *>(parentEntry), row);
-                }
-                endInsertRows();
-                return true;
-            }
-        }
+    if(!parent.isValid()) {
+        return false;
     }
-    return false;
+    auto *const parentEntry = static_cast<Entry *>(parent.internalPointer());
+    if(!parentEntry || parentEntry->type() != EntryType::Node) {
+        return false;
+    }
+    beginInsertRows(parent, row, row + count - 1);
+    for(int end = row + count; row < end; ++row) {
+        Entry *newEntry;
+        switch(m_insertType) {
+        case EntryType::Node:
+            newEntry = new NodeEntry;
+            break;
+        case EntryType::Account:
+            newEntry = new AccountEntry;
+            break;
+        default:
+            return false; // should never be reached, just to suppress compiler warning
+        }
+        newEntry->setParent(static_cast<NodeEntry *>(parentEntry), row);
+    }
+    endInsertRows();
+    return true;
 }
 
 bool EntryModel::removeRows(int row, int count, const QModelIndex &parent)
@@ -421,17 +425,17 @@ bool EntryModel::removeRows(int row, int count, const QModelIndex &parent)
         return push(new EntryModelRemoveRowsCommand(this, row, count, parent));
     }
 #endif
-    if(parent.isValid() && count > 0) {
-        if(Entry *parentEntry = static_cast<Entry *>(parent.internalPointer())) {
-            if(parentEntry->type() == EntryType::Node) {
-                beginRemoveRows(parent, row, row + count - 1);
-                static_cast<NodeEntry *>(parentEntry)->deleteChildren(row, row + count);
-                endRemoveRows();
-                return true;
-            }
-        }
+    if(!parent.isValid() || count <= 0) {
+        return false;
     }
-    return false;
+    auto *const parentEntry = static_cast<Entry *>(parent.internalPointer());
+    if(!parentEntry || parentEntry->type() != EntryType::Node) {
+        return false;
+    }
+    beginRemoveRows(parent, row, row + count - 1);
+    static_cast<NodeEntry *>(parentEntry)->deleteChildren(row, row + count);
+    endRemoveRows();
+    return true;
 }
 
 bool EntryModel::moveRows(const QModelIndex &sourceParent, int sourceRow, int count, const QModelIndex &destinationParent, int destinationChild)
@@ -442,41 +446,42 @@ bool EntryModel::moveRows(const QModelIndex &sourceParent, int sourceRow, int co
     }
 #endif
     // check validation of specified arguments
-    if(sourceParent.isValid() && destinationParent.isValid()
-            && sourceRow >= 0 && count > 0
-            && entry(sourceParent)->type() == EntryType::Node // source and destination parent entries
-            && entry(destinationParent)->type() == EntryType::Node) { // need to be node entries
-        // determine the source parent entry and dest parent entry as node entries
-        NodeEntry *srcParentEntry = static_cast<NodeEntry *>(sourceParent.internalPointer());
-        NodeEntry *destParentEntry = static_cast<NodeEntry *>(destinationParent.internalPointer());
-        // source rows must be within the valid range
-        if(static_cast<size_t>(sourceRow + count) <= srcParentEntry->children().size()
-                // if source and destination parent are the same the destination child mustn't be in the source range
-                && (srcParentEntry != destParentEntry || (destinationChild < sourceRow || (sourceRow + count) < destinationChild))) {
-            // do not move a row to one of its own children! -> check before
-            for(int index = 0; index < count; ++index) {
-                Entry *toMove = srcParentEntry->children().at(sourceRow + index);
-                if(toMove->type() == EntryType::Node) {
-                    if(destParentEntry->isIndirectChildOf(static_cast<NodeEntry *>(toMove))) {
-                        return false;
-                    }
-                }
+    if(!sourceParent.isValid() || !destinationParent.isValid()
+            || sourceRow < 0 || count <= 0
+            || entry(sourceParent)->type() != EntryType::Node // source and destination parent entries
+            || entry(destinationParent)->type() != EntryType::Node) { // need to be node entries
+        return false;
+    }
+    // determine the source parent entry and dest parent entry as node entries
+    auto *const srcParentEntry = static_cast<NodeEntry *>(sourceParent.internalPointer());
+    auto *const destParentEntry = static_cast<NodeEntry *>(destinationParent.internalPointer());
+    // source rows must be within the valid range
+    if(static_cast<size_t>(sourceRow + count) > srcParentEntry->children().size()
+            // if source and destination parent are the same the destination child mustn't be in the source range
+            || !(srcParentEntry != destParentEntry || (destinationChild < sourceRow || (sourceRow + count) < destinationChild))) {
+        return false;
+    }
+    // do not move a row to one of its own children! -> check before
+    for(int index = 0; index < count; ++index) {
+        Entry *toMove = srcParentEntry->children()[static_cast<size_t>(sourceRow + index)];
+        if(toMove->type() == EntryType::Node) {
+            if(destParentEntry->isIndirectChildOf(static_cast<NodeEntry *>(toMove))) {
+                return false;
             }
-            // actually perform the move operation
-            beginMoveRows(sourceParent, sourceRow, sourceRow + count - 1, destinationParent, destinationChild);
-            for(int index = 0; index < count; ++index) {
-                Entry *toMove = srcParentEntry->children().at(sourceRow + index);
-                if(srcParentEntry == destParentEntry && sourceRow < destinationChild) {
-                    toMove->setParent(destParentEntry, destinationChild + index - 1);
-                } else {
-                    toMove->setParent(destParentEntry, destinationChild + index);
-                }
-            }
-            endMoveRows();
-            return true;
         }
     }
-    return false;
+    // actually perform the move operation
+    beginMoveRows(sourceParent, sourceRow, sourceRow + count - 1, destinationParent, destinationChild);
+    for(int index = 0; index < count; ++index) {
+        Entry *toMove = srcParentEntry->children()[static_cast<size_t>(sourceRow + index)];
+        if(srcParentEntry == destParentEntry && sourceRow < destinationChild) {
+            toMove->setParent(destParentEntry, destinationChild + index - 1);
+        } else {
+            toMove->setParent(destParentEntry, destinationChild + index);
+        }
+    }
+    endMoveRows();
+    return true;
 }
 
 QStringList EntryModel::mimeTypes() const
@@ -497,16 +502,17 @@ QMimeData *EntryModel::mimeData(const QModelIndexList &indexes) const
     QStringList plainTextParts;
     QByteArray encoded;
     QDataStream dataStream(&encoded, QIODevice::WriteOnly);
-    foreach(const QModelIndex &index, indexes) {
-        if(index.isValid()) {
-            Entry *entry = static_cast<Entry *>(index.internalPointer());
-            list<string> path = entry->path();
-            dataStream << static_cast<quint32>(path.size());
-            for(const string &part : path) {
-                dataStream << QString::fromStdString(part);
-            }
-            plainTextParts << QString::fromStdString(entry->label());
+    for(const QModelIndex &index : indexes) {
+        if(!index.isValid()) {
+            continue;
         }
+        const auto *const entry = static_cast<const Entry *>(index.internalPointer());
+        const auto path(entry->path());
+        dataStream << static_cast<quint32>(path.size());
+        for(const string &part : path) {
+            dataStream << QString::fromStdString(part);
+        }
+        plainTextParts << QString::fromStdString(entry->label());
     }
     data->setData(types.at(0), encoded);
     data->setText(plainTextParts.join(QStringLiteral(", ")));
@@ -533,7 +539,7 @@ bool EntryModel::dropMimeData(const QMimeData *data, Qt::DropAction action, int
         column = 0;
     }
     // decode and insert
-    QByteArray encoded = data->data(format);
+    QByteArray encoded(data->data(format));
     QDataStream stream(&encoded, QIODevice::ReadOnly);
     int moved = 0;
     while(!stream.atEnd()) {
@@ -545,12 +551,13 @@ bool EntryModel::dropMimeData(const QMimeData *data, Qt::DropAction action, int
             stream >> part;
             path.push_back(part.toStdString());
         }
-        if(Entry *entry = m_rootEntry->entryByPath(path, true)) {
-            if(NodeEntry *srcParentEntry = entry->parent()) {
-                if(moveRows(index(srcParentEntry), entry->index(), 1, parent, row)) {
-                    ++moved;
-                }
-            }
+        auto *const entry = m_rootEntry->entryByPath(path, true);
+        if(!entry) {
+            continue;
+        }
+        auto *const srcParentEntry = entry->parent();
+        if(srcParentEntry && moveRows(index(srcParentEntry), entry->index(), 1, parent, row)) {
+            ++moved;
         }
     }
     return false;
diff --git a/model/fieldmodel.cpp b/model/fieldmodel.cpp
index 61b93a6..152d9c3 100644
--- a/model/fieldmodel.cpp
+++ b/model/fieldmodel.cpp
@@ -55,60 +55,62 @@ FieldModel::FieldModel(QUndoStack *undoStack, QObject *parent) :
  */
 void FieldModel::setAccountEntry(AccountEntry *entry)
 {
-    if(entry != m_accountEntry) {
-        beginResetModel();
-        if((m_accountEntry = entry)) {
-            m_fields = &entry->fields();
-        } else {
-            m_fields = nullptr;
-        }
-        endResetModel();
+    if(entry == m_accountEntry) {
+        return;
     }
+    beginResetModel();
+    if((m_accountEntry = entry)) {
+        m_fields = &entry->fields();
+    } else {
+        m_fields = nullptr;
+    }
+    endResetModel();
 }
 
 QVariant FieldModel::data(const QModelIndex &index, int role) const
 {
-    if(index.isValid() && m_fields && index.row() >= 0) {
-        // return data for existent field
-        if(static_cast<size_t>(index.row()) < m_fields->size()) {
-            switch(role) {
-            case Qt::DisplayRole:
-            case Qt::EditRole:
-                switch(index.column()) {
-                case 0:
-                    return QString::fromStdString(m_fields->at(index.row()).name());
-                case 1:
-                    return (m_passwordVisibility == PasswordVisibility::Always
-                            || role == Qt::EditRole
-                            || m_fields->at(index.row()).type() != FieldType::Password)
-                            ? QString::fromStdString(m_fields->at(index.row()).value())
-                            : QString(m_fields->at(index.row()).value().size(), QChar(0x2022));
-                default:
-                    ;
-                }
-                break;
-            case FieldTypeRole:
-                return static_cast<int>(m_fields->at(index.row()).type());
+    if(!index.isValid() || !m_fields || index.row() < 0) {
+        return QVariant();
+    }
+    // return data for existent field
+    if(static_cast<size_t>(index.row()) < m_fields->size()) {
+        switch(role) {
+        case Qt::DisplayRole:
+        case Qt::EditRole:
+            switch(index.column()) {
+            case 0:
+                return QString::fromStdString((*m_fields)[static_cast<size_t>(index.row())].name());
+            case 1:
+                return (m_passwordVisibility == PasswordVisibility::Always
+                        || role == Qt::EditRole
+                        || (*m_fields)[static_cast<size_t>(index.row())].type() != FieldType::Password)
+                        ? QString::fromStdString((*m_fields)[static_cast<size_t>(index.row())].value())
+                        : QString((*m_fields)[static_cast<size_t>(index.row())].value().size(), QChar(0x2022));
             default:
                 ;
             }
-        // return data for empty field at the end which enables the user to append fields
-        } else if(static_cast<size_t>(index.row()) == m_fields->size()) {
-            switch(role) {
-            case Qt::DisplayRole:
-            case Qt::EditRole:
-                switch(index.column()) {
-                case 0:
-                    return QString();
-                case 1:
-                    return QString();
-                default:
-                    ;
-                }
-                break;
+            break;
+        case FieldTypeRole:
+            return static_cast<int>((*m_fields)[static_cast<size_t>(index.row())].type());
+        default:
+            ;
+        }
+    // return data for empty field at the end which enables the user to append fields
+    } else if(static_cast<size_t>(index.row()) == m_fields->size()) {
+        switch(role) {
+        case Qt::DisplayRole:
+        case Qt::EditRole:
+            switch(index.column()) {
+            case 0:
+                return QString();
+            case 1:
+                return QString();
             default:
                 ;
             }
+            break;
+        default:
+            ;
         }
     }
     return QVariant();
@@ -116,14 +118,16 @@ QVariant FieldModel::data(const QModelIndex &index, int role) const
 
 QMap<int, QVariant> FieldModel::itemData(const QModelIndex &index) const
 {
-    static int roles[] = {Qt::EditRole, FieldTypeRole};
-    QMap<int, QVariant> roleMap;
-    for(int role : roles) {
-        QVariant variantData = data(index, role);
-        if (variantData.isValid()) {
-            roleMap.insert(role, variantData);
+    static const auto roleMap = [this, index] {
+        QMap<int, QVariant> roleMap;
+        for(const auto role : initializer_list<int>{Qt::EditRole, FieldTypeRole}) {
+            const auto variantData(data(index, role));
+            if (variantData.isValid()) {
+                roleMap.insert(role, variantData);
+            }
         }
-    }
+        return roleMap;
+    }();
     return roleMap;
 }
 
@@ -134,86 +138,86 @@ bool FieldModel::setData(const QModelIndex &index, const QVariant &value, int ro
         return push(new FieldModelSetValueCommand(this, index, value, role));
     }
 #endif
+    if(!index.isValid() || !m_fields || index.row() < 0) {
+        return false;
+    }
     QVector<int> roles;
-    if(index.isValid() && m_fields && index.row() >= 0) {
+    if(static_cast<size_t>(index.row()) < m_fields->size()) {
         // set data for existing field
-        if(static_cast<size_t>(index.row()) < m_fields->size()) {
-            switch(role) {
-            case Qt::EditRole:
-                switch(index.column()) {
-                case 0:
-                    m_fields->at(index.row()).setName(value.toString().toStdString());
-                    roles << role;
-                    break;
-                case 1:
-                    m_fields->at(index.row()).setValue(value.toString().toStdString());
-                    roles << role;
-                    break;
-                default:
-                    ;
-                }
+        switch(role) {
+        case Qt::EditRole:
+            switch(index.column()) {
+            case 0:
+                m_fields->at(index.row()).setName(value.toString().toStdString());
+                roles << role;
                 break;
-            case FieldTypeRole: {
-                bool ok;
-                int fieldType = value.toInt(&ok);
-                if(ok && Field::isValidType(fieldType)) {
-                    roles << role;
-                    m_fields->at(index.row()).setType(static_cast<FieldType>(fieldType));
-                }
-                break;
-            } default:
-                ;
-            }
-            // remove last field if empty, showing an empty field at the end to enabled appending new rows is provided by the data method
-            if(!roles.isEmpty() && static_cast<size_t>(index.row()) == m_fields->size() - 1 && m_fields->at(index.row()).isEmpty()) {
-                beginRemoveRows(index.parent(), index.row(), index.row());
-                m_fields->pop_back();
-                endRemoveRows();
-            }
-        // set data for a new field emplaced at the end of the field list
-        } else if(static_cast<size_t>(index.row()) == m_fields->size() && !value.toString().isEmpty()) {
-            switch(role) {
-            case Qt::DisplayRole:
-            case Qt::EditRole:
-                switch(index.column()) {
-                case 0:
-                    beginInsertRows(index.parent(), rowCount(), rowCount());
-                    m_fields->emplace_back(m_accountEntry);
-                    m_fields->back().setName(value.toString().toStdString());
-                    endInsertRows();
-                    roles << role;
-                    break;
-                case 1:
-                    beginInsertRows(index.parent(), rowCount(), rowCount());
-                    m_fields->emplace_back(m_accountEntry);
-                    m_fields->back().setValue(value.toString().toStdString());
-                    endInsertRows();
-                    roles << role;
-                    break;
-                default:
-                    ;
-                }
+            case 1:
+                m_fields->at(index.row()).setValue(value.toString().toStdString());
+                roles << role;
                 break;
             default:
                 ;
             }
+            break;
+        case FieldTypeRole: {
+            bool ok;
+            int fieldType = value.toInt(&ok);
+            if(ok && Field::isValidType(fieldType)) {
+                roles << role;
+                m_fields->at(index.row()).setType(static_cast<FieldType>(fieldType));
+            }
+            break;
+        } default:
+            ;
+        }
+        // remove last field if empty, showing an empty field at the end to enabled appending new rows is provided by the data method
+        if(!roles.isEmpty() && static_cast<size_t>(index.row()) == m_fields->size() - 1 && m_fields->at(index.row()).isEmpty()) {
+            beginRemoveRows(index.parent(), index.row(), index.row());
+            m_fields->pop_back();
+            endRemoveRows();
+        }
+    } else if(static_cast<size_t>(index.row()) == m_fields->size() && !value.toString().isEmpty()) {
+        // set data for a new field emplaced at the end of the field list
+        switch(role) {
+        case Qt::DisplayRole:
+        case Qt::EditRole:
+            switch(index.column()) {
+            case 0:
+                beginInsertRows(index.parent(), rowCount(), rowCount());
+                m_fields->emplace_back(m_accountEntry);
+                m_fields->back().setName(value.toString().toStdString());
+                endInsertRows();
+                roles << role;
+                break;
+            case 1:
+                beginInsertRows(index.parent(), rowCount(), rowCount());
+                m_fields->emplace_back(m_accountEntry);
+                m_fields->back().setValue(value.toString().toStdString());
+                endInsertRows();
+                roles << role;
+                break;
+            default:
+                ;
+            }
+            break;
+        default:
+            ;
         }
     }
     // return false if nothing could be changed
     if(roles.isEmpty()) {
         return false;
-    } else {
-        // some roles affect other roles
-        switch(role) {
-        case Qt::EditRole:
-            roles << Qt::DisplayRole;
-            break;
-        case FieldTypeRole:
-            roles << Qt::DisplayRole << Qt::EditRole;
-            break;
-        default:
-            ;
-        }
+    }
+    // some roles affect other roles
+    switch(role) {
+    case Qt::EditRole:
+        roles << Qt::DisplayRole;
+        break;
+    case FieldTypeRole:
+        roles << Qt::DisplayRole << Qt::EditRole;
+        break;
+    default:
+        ;
     }
     // emit data changed signal on sucess
     emit dataChanged(index, index, roles);
@@ -267,13 +271,13 @@ bool FieldModel::insertRows(int row, int count, const QModelIndex &parent)
         return push(new FieldModelInsertRowsCommand(this, row, count));
     }
 #endif
-    if(!parent.isValid() && row >= 0 && count > 0 && static_cast<size_t>(row) <= m_fields->size()) {
-        beginInsertRows(parent, row, row + count - 1);
-        m_fields->insert(m_fields->begin() + row, count, Field(m_accountEntry));
-        endInsertRows();
-        return true;
+    if(parent.isValid() || row < 0 || count <= 0 || static_cast<size_t>(row + count) > m_fields->size()) {
+        return false;
     }
-    return false;
+    beginInsertRows(parent, row, row + count - 1);
+    m_fields->insert(m_fields->begin() + row, static_cast<size_t>(count), Field(m_accountEntry));
+    endInsertRows();
+    return true;
 }
 
 bool FieldModel::removeRows(int row, int count, const QModelIndex &parent)
@@ -283,21 +287,18 @@ bool FieldModel::removeRows(int row, int count, const QModelIndex &parent)
         return push(new FieldModelRemoveRowsCommand(this, row, count));
     }
 #endif
-    if(!parent.isValid() && row >= 0 && count > 0 && static_cast<size_t>(row + count) <= m_fields->size()) {
-        beginRemoveRows(parent, row, row + count - 1);
-        m_fields->erase(m_fields->begin() + row, m_fields->begin() + row + count);
-        endRemoveRows();
-        return true;
+    if(parent.isValid() || row < 0 || count <= 0 || static_cast<size_t>(row + count) > m_fields->size()) {
+        return false;
     }
-    return false;
+    beginRemoveRows(parent, row, row + count - 1);
+    m_fields->erase(m_fields->begin() + row, m_fields->begin() + row + count);
+    endRemoveRows();
 }
 
 bool FieldModel::dropMimeData(const QMimeData *data, Qt::DropAction action, int row, int column, const QModelIndex &parent)
 {
-    if(!QAbstractTableModel::dropMimeData(data, action, row, column, parent)) {
-        if(data->hasText()) {
-            return setData(parent, data->text(), Qt::EditRole);
-        }
+    if(!QAbstractTableModel::dropMimeData(data, action, row, column, parent) && data->hasText()) {
+        return setData(parent, data->text(), Qt::EditRole);
     }
     return false;
 }
@@ -310,13 +311,14 @@ QStringList FieldModel::mimeTypes() const
 QMimeData *FieldModel::mimeData(const QModelIndexList &indexes) const
 {
     QMimeData *data = QAbstractTableModel::mimeData(indexes);
-    if(!indexes.isEmpty()) {
-        QStringList result;
-        foreach(const QModelIndex &index, indexes) {
-            result << index.data(Qt::EditRole).toString();
-        }
-        data->setText(result.join(QChar('\n')));
+    if(indexes.isEmpty()) {
+        return data;
     }
+    QStringList result;
+    for(const QModelIndex &index : indexes) {
+        result << index.data(Qt::EditRole).toString();
+    }
+    data->setText(result.join(QChar('\n')));
     return data;
 }
 
@@ -328,7 +330,7 @@ QMimeData *FieldModel::mimeData(const QModelIndexList &indexes) const
 const Field *FieldModel::field(size_t row) const
 {
     if(m_fields && row < m_fields->size()) {
-        return &m_fields->at(row);
+        return &(*m_fields)[row];
     }
     return nullptr;
 }
diff --git a/quickgui/applicationpaths.h b/quickgui/applicationpaths.h
index c9465a1..4c03c6a 100644
--- a/quickgui/applicationpaths.h
+++ b/quickgui/applicationpaths.h
@@ -30,10 +30,12 @@ inline QString ApplicationPaths::path(QStandardPaths::StandardLocation location)
 {
     QString path = QStandardPaths::standardLocations(location).value(0);
     QDir dir(path);
-    if (!dir.exists())
+    if (!dir.exists()) {
         dir.mkpath(path);
-    if (!path.isEmpty() && !path.endsWith("/"))
+    }
+    if (!path.isEmpty() && !path.endsWith("/")) {
         path += "/";
+    }
     return path;
 }
 } // namespace QtGui