Make Machine Settings compatible with machines that use variants (UM2+)

For machines that use variants, a second variant container is added between the machine definition and the variant.

plugins/MachineSettingsAction/MachineSettingsAction.py

@@ -21,27 +21,56 @@ class MachineSettingsAction(MachineAction):
 
         self._container_index = 0
 
-        cura.Settings.CuraContainerRegistry.getInstance().containerAdded.connect(self._onContainerAdded)
+        self._container_registry = UM.Settings.ContainerRegistry.getInstance()
+        self._container_registry.containerAdded.connect(self._onContainerAdded)
 
     def _reset(self):
         global_container_stack = UM.Application.getInstance().getGlobalContainerStack()
-        if global_container_stack:
+        if not global_container_stack:
+            return
+
+        # First check if there is a variant previously generated by this machine
+        machine_settings_variant = global_container_stack.findContainer({"type": "variant", "subtype": "machine_settings"})
+        if not machine_settings_variant:
+            # There may be a variant created by the UMOUpgradeSelection machine action
+            machine_settings_variant = global_container_stack.findContainer({"type": "variant", "id": global_container_stack.getName() + "_variant"})
+
+        if not machine_settings_variant:
             variant = global_container_stack.findContainer({"type": "variant"})
-            if variant:
-                variant_index = global_container_stack.getContainerIndex(variant)
-                if variant_index != self._container_index:
-                    self._container_index = variant_index
-                    self.containerIndexChanged.emit()
-                if variant.getId() == "empty_variant":
-                    self._createVariant(global_container_stack, self._container_index)
-
-    def _createVariant(self, global_container_stack):
-        # Create and switch to a variant to store the settings in
-        new_variant = UM.Settings.InstanceContainer(global_container_stack.getName() + "_variant")
-        new_variant.addMetaDataEntry("type", "variant")
-        new_variant.setDefinition(global_container_stack.getBottom())
-        UM.Settings.ContainerRegistry.getInstance().addContainer(new_variant)
-        global_container_stack.replaceContainer(self._container_index, new_variant)
+            if variant and variant.getId() == "empty_variant":
+                # There is an empty variant that we can use to store the machine settings
+                container_index = global_container_stack.getContainerIndex(variant)
+                machine_settings_variant = self._createMachineVariant(global_container_stack, container_index)
+            else:
+                # Add a second variant before the current variant to store the machine settings
+                machine_settings_variant = self._createMachineVariant(global_container_stack)
+
+        # Notify the UI in which container to store the machine settings data
+        container_index = global_container_stack.getContainerIndex(machine_settings_variant)
+        if container_index != self._container_index:
+            self._container_index = container_index
+            self.containerIndexChanged.emit()
+
+    def _createMachineSettingsVariant(self, global_container_stack, container_index = None):
+        machine_settings_variant = UM.Settings.InstanceContainer(global_container_stack.getName() + "_variant")
+        if global_container_stack.getMetaDataEntry("has_variants", False):
+            # If the current machine uses visible variants (eg for nozzle selection), make sure
+            # not to add this variant to the list.
+            definition = self._container_registry.findDefinitionContainers(id="fdmprinter")[0]
+        else:
+            definition = global_container_stack.getBottom()
+        machine_settings_variant.setDefinition(definition)
+        machine_settings_variant.addMetaDataEntry("type", "variant")
+        machine_settings_variant.addMetaDataEntry("subtype", "machine_settings")
+
+        self._container_registry.addContainer(machine_settings_variant)
+
+        if container_index:
+            global_container_stack.replaceContainer(container_index, machine_settings_variant)
+        else:
+            index = len(global_container_stack.getContainers()) - 1
+            global_container_stack.addContainer(machine_settings_variant, index)
+        return machine_settings_variant
 
     containerIndexChanged = pyqtSignal()
 
@@ -56,10 +85,6 @@ class MachineSettingsAction(MachineAction):
                 # Multiextruder printers are not currently supported
                 UM.Logger.log("d", "Not attaching MachineSettingsAction to %s; Multi-extrusion printers are not supported", container.getId())
                 return
-            if container.getMetaDataEntry("has_variants", False):
-                # Machines that use variants are not currently supported
-                UM.Logger.log("d", "Not attaching MachineSettingsAction to %s; Machines that use variants are not supported", container.getId())
-                return
 
             UM.Application.getInstance().getMachineActionManager().addSupportedAction(container.getId(), self.getKey())
 
@@ -90,7 +115,7 @@ class MachineSettingsAction(MachineAction):
                     # Set the material container to a sane default
                     if material_container.getId() == "empty_material":
                         search_criteria = { "type": "material", "definition": "fdmprinter", "id": "*pla*" }
-                        containers = UM.Settings.ContainerRegistry.getInstance().findInstanceContainers(**search_criteria)
+                        containers = self._container_registry.findInstanceContainers(**search_criteria)
                         if containers:
                             global_container_stack.replaceContainer(material_index, containers[0])
                 else:
@@ -99,7 +124,7 @@ class MachineSettingsAction(MachineAction):
                     if "has_materials" in global_container_stack.getMetaData():
                         global_container_stack.removeMetaDataEntry("has_materials")
 
-                    empty_material = UM.Settings.ContainerRegistry.getInstance().findInstanceContainers(id = "empty_material")[0]
+                    empty_material = self._container_registry.findInstanceContainers(id = "empty_material")[0]
                     global_container_stack.replaceContainer(material_index, empty_material)
 
                 UM.Application.getInstance().globalContainerStackChanged.emit()