Fix: Consider all active extruder intent profiles for display.

Remove the notion of a singular 'active' extruder from the code.
Visibility of intent profiles should consider all enabled extruders.
This fix makes sure that it doesn't matter in what order materials are
loaded, the available intent profiles will be the same.

CURA-6840

cura/Machines/Models/IntentModel.py

@@ -1,18 +1,15 @@
 # Copyright (c) 2019 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
-
+from typing import Optional, Dict, Any, Set, List
-from typing import Optional, List, Dict, Any
 
 from PyQt5.QtCore import Qt, QObject, pyqtProperty, pyqtSignal
 
+import cura.CuraApplication
 from UM.Qt.ListModel import ListModel
 from UM.Settings.ContainerRegistry import ContainerRegistry
 from UM.Settings.SettingFunction import SettingFunction
-
+from cura.Machines import MaterialNode, QualityGroup
 from cura.Machines.ContainerTree import ContainerTree
-from cura.Settings.ExtruderManager import ExtruderManager
-from cura.Settings.IntentManager import IntentManager
-import cura.CuraApplication
 
 
 class IntentModel(ListModel):
@@ -65,47 +62,16 @@ class IntentModel(ListModel):
             return
         quality_groups = ContainerTree.getInstance().getCurrentQualityGroups()
 
-        container_tree = ContainerTree.getInstance()
+        material_nodes = self._get_active_materials()
-        machine_node = container_tree.machines[global_stack.definition.getId()]
-
-        # We can't just look at the active extruder, since it is possible for only one extruder to have an intent
-        # and the other extruders have no intent (eg, default). It is not possible for one extruder to have intent A and
-        # the other to have B.
-        # So we will use the first extruder that we find that has an intent that is not default as the "active" extruder
-
-        active_extruder = None
-        for extruder in global_stack.extruderList:
-            if not extruder.isEnabled:
-                continue
-            if extruder.intent.getMetaDataEntry("intent_category", "default") == "default":
-                if active_extruder is None:
-                    active_extruder = extruder  # If there is no extruder found and the intent is default, use that.
-            else:  # We found an intent, use that extruder as "active"
-                active_extruder = extruder
-
-        if not active_extruder:
-            return
-        active_variant_name = active_extruder.variant.getMetaDataEntry("name")
-        active_variant_node = machine_node.variants[active_variant_name]
-        active_material_node = active_variant_node.materials[active_extruder.material.getMetaDataEntry("base_file")]
 
         layer_heights_added = []
-        for quality_id, quality_node in active_material_node.qualities.items():
-            if quality_node.quality_type not in quality_groups:  # Don't add the empty quality type (or anything else that would crash, defensively).
-                continue
-            quality_group = quality_groups[quality_node.quality_type]
-            layer_height = self._fetchLayerHeight(quality_group)
 
-            for intent_id, intent_node in quality_node.intents.items():
+        for material_node in material_nodes:
-                if intent_node.intent_category != self._intent_category:
+            intents = self._get_intents_for_material(material_node, quality_groups)
-                    continue
+            for intent in intents:
-                layer_heights_added.append(layer_height)
+                if intent["layer_height"] not in layer_heights_added:
-                new_items.append({"name": quality_group.name,
+                    new_items.append(intent)
-                                  "quality_type": quality_group.quality_type,
+                    layer_heights_added.append(intent["layer_height"])
-                                  "layer_height": layer_height,
-                                  "available": quality_group.is_available,
-                                  "intent_category": self._intent_category
-                                  })
 
         # Now that we added all intents that we found something for, ensure that we set add ticks (and layer_heights)
         # for all groups that we don't have anything for (and set it to not available)
@@ -124,8 +90,43 @@ class IntentModel(ListModel):
         new_items = sorted(new_items, key=lambda x: x["layer_height"])
         self.setItems(new_items)
 
+    ##  Get the active materials for all extruders. No duplicates will be returned
+    def _get_active_materials(self) -> Set[MaterialNode]:
+        global_stack = cura.CuraApplication.CuraApplication.getInstance().getGlobalContainerStack()
+        container_tree = ContainerTree.getInstance()
+        machine_node = container_tree.machines[global_stack.definition.getId()]
+        nodes = set([])
+
+        for extruder in global_stack.extruderList:
+            active_variant_name = extruder.variant.getMetaDataEntry("name")
+            active_variant_node = machine_node.variants[active_variant_name]
+            active_material_node = active_variant_node.materials[extruder.material.getMetaDataEntry("base_file")]
+            nodes.add(active_material_node)
+
+        return nodes
+
+    def _get_intents_for_material(self, active_material_node: MaterialNode, quality_groups: Dict[str, QualityGroup]) -> List[Dict[str, Any]]:
+        extruder_intents = []  # type: List[Dict[str, Any]]
+
+        for quality_id, quality_node in active_material_node.qualities.items():
+            if quality_node.quality_type not in quality_groups:  # Don't add the empty quality type (or anything else that would crash, defensively).
+                continue
+            quality_group = quality_groups[quality_node.quality_type]
+            layer_height = self._fetchLayerHeight(quality_group)
+
+            for intent_id, intent_node in quality_node.intents.items():
+                if intent_node.intent_category != self._intent_category:
+                    continue
+                extruder_intents.append({"name": quality_group.name,
+                                  "quality_type": quality_group.quality_type,
+                                  "layer_height": layer_height,
+                                  "available": quality_group.is_available,
+                                  "intent_category": self._intent_category
+                                  })
+        return extruder_intents
+
     #TODO: Copied this from QualityProfilesDropdownMenuModel for the moment. This code duplication should be fixed.
-    def _fetchLayerHeight(self, quality_group) -> float:
+    def _fetchLayerHeight(self, quality_group: QualityGroup) -> float:
         global_stack = cura.CuraApplication.CuraApplication.getInstance().getMachineManager().activeMachine
         if not self._layer_height_unit:
             unit = global_stack.definition.getProperty("layer_height", "unit")