From 68231c957d24b1b9a56be67d151db4f42ad7cc47 Mon Sep 17 00:00:00 2001
From: Remco Burema <r.burema@ultimaker.com>
Date: Tue, 13 Jun 2023 15:34:38 +0200
Subject: [PATCH] Add settings-function to get an extruder based on a property.

We wanted to select an extruder based on wether or not it has support-material, so that the user doesn't have to think about selecting a support extruder any more and in most cases, can't forget anymore either. The formula present in fdmprinter to do that was not only an unreadable nightmare, but also very slow. We decided to pull most of that functionality into the settings-function machinery instead (but just a bit more generic so other properties can be selected, not just 'material_is_support_material').

done as part of finishing off CURA-10643
---
 cura/CuraApplication.py                   |  1 +
 cura/Settings/CuraFormulaFunctions.py     | 24 ++++++++++++++++++++---
 resources/definitions/fdmprinter.def.json |  2 +-
 3 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/cura/CuraApplication.py b/cura/CuraApplication.py
index 1073288b7a..6b04503ebc 100755
--- a/cura/CuraApplication.py
+++ b/cura/CuraApplication.py
@@ -408,6 +408,7 @@ class CuraApplication(QtApplication):
 
         SettingFunction.registerOperator("extruderValue", self._cura_formula_functions.getValueInExtruder)
         SettingFunction.registerOperator("extruderValues", self._cura_formula_functions.getValuesInAllExtruders)
+        SettingFunction.registerOperator("anyExtruderNrWithOrDefault", self._cura_formula_functions.getAnyExtruderPositionWithOrDefault)
         SettingFunction.registerOperator("resolveOrValue", self._cura_formula_functions.getResolveOrValue)
         SettingFunction.registerOperator("defaultExtruderPosition", self._cura_formula_functions.getDefaultExtruderPosition)
         SettingFunction.registerOperator("valueFromContainer", self._cura_formula_functions.getValueFromContainerAtIndex)
diff --git a/cura/Settings/CuraFormulaFunctions.py b/cura/Settings/CuraFormulaFunctions.py
index 13e3dfb26e..fd6555e679 100644
--- a/cura/Settings/CuraFormulaFunctions.py
+++ b/cura/Settings/CuraFormulaFunctions.py
@@ -58,9 +58,7 @@ class CuraFormulaFunctions:
 
         return value
 
-    # Gets all extruder values as a list for the given property.
-    def getValuesInAllExtruders(self, property_key: str,
-                                context: Optional["PropertyEvaluationContext"] = None) -> List[Any]:
+    def _getActiveExtruders(self, context: Optional["PropertyEvaluationContext"] = None) -> List[str]:
         machine_manager = self._application.getMachineManager()
         extruder_manager = self._application.getExtruderManager()
 
@@ -73,7 +71,17 @@ class CuraFormulaFunctions:
             # only include values from extruders that are "active" for the current machine instance
             if int(extruder.getMetaDataEntry("position")) >= global_stack.getProperty("machine_extruder_count", "value", context = context):
                 continue
+            result.append(extruder)
 
+        return result
+
+    # Gets all extruder values as a list for the given property.
+    def getValuesInAllExtruders(self, property_key: str,
+                                context: Optional["PropertyEvaluationContext"] = None) -> List[Any]:
+        global_stack = self._application.getMachineManager().activeMachine
+
+        result = []
+        for extruder in self._getActiveExtruders(context):
             value = extruder.getRawProperty(property_key, "value", context = context)
 
             if value is None:
@@ -89,6 +97,16 @@ class CuraFormulaFunctions:
 
         return result
 
+    # Get the first extruder that adheres to a specific (boolean) property, like 'material_is_support_material'.
+    def getAnyExtruderPositionWithOrDefault(self, filter_key: str,
+                               context: Optional["PropertyEvaluationContext"] = None) -> str:
+        for extruder in self._getActiveExtruders(context):
+            value = extruder.getRawProperty(filter_key, "value", context=context)
+            if value is None or not value:
+                continue
+            return str(extruder.position)
+        return self.getDefaultExtruderPosition()
+
     # Get the resolve value or value for a given key.
     def getResolveOrValue(self, property_key: str, context: Optional["PropertyEvaluationContext"] = None) -> Any:
         machine_manager = self._application.getMachineManager()
diff --git a/resources/definitions/fdmprinter.def.json b/resources/definitions/fdmprinter.def.json
index 706aa52905..566e32b349 100644
--- a/resources/definitions/fdmprinter.def.json
+++ b/resources/definitions/fdmprinter.def.json
@@ -4490,7 +4490,7 @@
                     "type": "extruder",
                     "default_value": "0",
                     "enabled": "(support_enable or support_meshes_present) and extruders_enabled_count > 1",
-                    "value": "[*map(lambda x: str(x).lower() == 'true', (extruderValues('support_enable') and extruderValues('material_is_support_material')))].index(True) if any([*map(lambda x: str(x).lower() == 'true', (extruderValues('support_enable') and extruderValues('material_is_support_material')))]) else int(defaultExtruderPosition())",
+                    "value": "int(anyExtruderNrWithOrDefault('material_is_support_material'))",
                     "settable_per_mesh": false,
                     "settable_per_extruder": false,
                     "children":