Add a "show internal" option to Qube Manager

By default, internal qubes should be hidden.
The option is available from View menu.
Also some minor reorganization of code, to avoid 'variable
not yet defined' errors.

fixes QubesOS/qubes-issues#8042

qubesmanager/qube_manager.py

@@ -671,12 +671,15 @@ def lessThan(self, left, right):
 
     # pylint: disable=too-many-return-statements
     def filterAcceptsRow(self, sourceRow, sourceParent):
-        if self.window.show_all.isChecked():
-            return super().filterAcceptsRow(sourceRow, sourceParent)
-
         index = self.sourceModel().index(sourceRow, 0, sourceParent)
         vm = self.sourceModel().data(index, Qt.UserRole)
 
+        # if hide internal is true, ignore all other filters
+        if not self.window.show_internal_action.isChecked() and vm.internal:
+            return False
+        if self.window.show_all.isChecked():
+            return super().filterAcceptsRow(sourceRow, sourceParent)
+
         if self.window.show_running.isChecked() and \
                 vm.state['power'] != 'Halted':
             return super().filterAcceptsRow(sourceRow, sourceParent)
@@ -748,45 +751,52 @@ def __init__(self, qt_app, qubes_app, dispatcher, _parent=None):
         self.fill_cache()
         self.qubes_model = QubesTableModel(self.qubes_cache)
 
-        self.proxy = QubesProxyModel(self)
-        self.proxy.setSourceModel(self.qubes_model)
-        self.proxy.setSortRole(Qt.UserRole + 1)
-        self.proxy.setSortCaseSensitivity(Qt.CaseInsensitive)
-        self.proxy.setFilterKeyColumn(2)
-        self.proxy.setFilterCaseSensitivity(Qt.CaseInsensitive)
-        self.proxy.layoutChanged.connect(self.save_sorting)
-        self.proxy.layoutChanged.connect(self.update_template_menu)
-        self.proxy.layoutChanged.connect(self.update_network_menu)
-
         self.show_running.stateChanged.connect(self.invalidate)
         self.show_halted.stateChanged.connect(self.invalidate)
         self.show_network.stateChanged.connect(self.invalidate)
         self.show_templates.stateChanged.connect(self.invalidate)
         self.show_standalone.stateChanged.connect(self.invalidate)
         self.show_all.stateChanged.connect(self.invalidate)
 
-        self.table.setModel(self.proxy)
-        self.table.setItemDelegateForColumn(3, StateIconDelegate())
-        self.table.resizeColumnsToContents()
-        selection_model = self.table.selectionModel()
-        selection_model.selectionChanged.connect(self.table_selection_changed)
-
-        self.table.setContextMenuPolicy(Qt.CustomContextMenu)
-        self.table.customContextMenuRequested.connect(self.open_context_menu)
-
         # Create view menu
         for col_no, column in enumerate(self.qubes_model.columns_indices):
             action = self.menu_view.addAction(column)
             action.setData(column)
             action.setCheckable(True)
             action.toggled.connect(partial(self.showhide_column, col_no))
 
+        self.menu_view.addSeparator()
+        self.show_internal_action = self.menu_view.addAction(
+            self.tr('Show internal qubes'))
+        self.show_internal_action.setCheckable(True)
+        self.show_internal_action.toggled.connect(self.invalidate)
+
         self.menu_view.addSeparator()
         self.menu_view.addAction(self.action_toolbar)
         self.menu_view.addAction(self.action_menubar)
+
         self.menu_view.addSeparator()
         self.menu_view.addAction(self.action_compact_view)
 
+        self.proxy = QubesProxyModel(self)
+        self.proxy.setSourceModel(self.qubes_model)
+        self.proxy.setSortRole(Qt.UserRole + 1)
+        self.proxy.setSortCaseSensitivity(Qt.CaseInsensitive)
+        self.proxy.setFilterKeyColumn(2)
+        self.proxy.setFilterCaseSensitivity(Qt.CaseInsensitive)
+        self.proxy.layoutChanged.connect(self.save_sorting)
+        self.proxy.layoutChanged.connect(self.update_template_menu)
+        self.proxy.layoutChanged.connect(self.update_network_menu)
+
+        self.table.setModel(self.proxy)
+        self.table.setItemDelegateForColumn(3, StateIconDelegate())
+        self.table.resizeColumnsToContents()
+        selection_model = self.table.selectionModel()
+        selection_model.selectionChanged.connect(self.table_selection_changed)
+
+        self.table.setContextMenuPolicy(Qt.CustomContextMenu)
+        self.table.customContextMenuRequested.connect(self.open_context_menu)
+
         try:
             self.load_manager_settings()
         except Exception as ex:  # pylint: disable=broad-except
@@ -941,6 +951,8 @@ def save_showing(self):
                 self.show_templates.isChecked())
         self.manager_settings.setValue('show/standalone',
                 self.show_standalone.isChecked())
+        self.manager_settings.setValue('show/internal',
+                self.show_internal_action.isChecked())
         self.manager_settings.setValue('show/all', self.show_all.isChecked())
 
     def save_sorting(self):
@@ -1152,6 +1164,8 @@ def load_manager_settings(self):
         self.show_all.setChecked(self.manager_settings.value(
             'show/all', "true") == "true")
 
+        self.show_internal_action.setChecked(self.manager_settings.value(
+            'show/internal', "false") == "true")
         # load last window size
         self.resize(self.manager_settings.value("window_size",
                                                 QSize(1100, 600)))