Added SettingsInheritanceManager

CURA-2361

cura/Settings/SettingInheritanceManager.py

@@ -0,0 +1,72 @@
+from PyQt5.QtCore import QObject, pyqtSlot, pyqtProperty
+import UM.Settings
+from UM.Application import Application
+import cura.Settings
+
+class SettingInheritanceManager(QObject):
+    def __init__(self, parent = None):
+        super().__init__(parent)
+        Application.getInstance().globalContainerStackChanged.connect(self._onGlobalContainerChanged)
+        self._global_container_stack = None
+        self._onGlobalContainerChanged()
+
+        self._active_container_stack = None
+        cura.Settings.ExtruderManager.getInstance().activeExtruderChanged.connect(self._onActiveExtruderChanged)
+        self._onActiveExtruderChanged()
+        pass
+
+    @pyqtSlot()
+    def test(self):
+        print("test!")
+
+    def _onActiveExtruderChanged(self):
+        if self._active_container_stack:
+            self._active_container_stack.propertyChanged.disconnect(self._onPropertyChanged)
+
+        new_active_stack = cura.Settings.ExtruderManager.getInstance().getActiveExtruderStack()
+        if not new_active_stack:
+            new_active_stack = self._global_container_stack
+
+        if new_active_stack != self._active_container_stack:
+            # Check if changed
+            self._active_container_stack = new_active_stack
+            self._active_container_stack.propertyChanged.connect(self._onPropertyChanged)
+
+    def _onPropertyChanged(self, key, property_name):
+        if property_name == "value" and self._global_container_stack:
+
+            definitions = self._global_container_stack.getBottom().findDefinitions(key = key)
+            if not definitions:
+                return
+
+            # Pseudo code;
+            # Check if the property change caused a inheritance warning to trigger.
+            pass  # We need to do sum maaagic
+
+    # Check if a setting is being overwritten.
+    def _settingIsOverwritingInheritance(self, key):
+        has_setting_function = False
+        stack = self._active_container_stack
+        containers = []
+        while stack:
+            containers.extend(stack.getContainers())
+            stack = stack.getNextStack()
+
+        for container in containers:
+            try:
+                has_setting_function = isinstance(container.getProperty(key, "value"), UM.Settings.SettingFunction)
+            except AttributeError:
+                continue
+            if has_setting_function:
+                break
+        return has_setting_function and not isinstance(self._active_container_stack.getTop().getProperty(key, "value"), UM.Settings.SettingFunction)
+
+    def _update(self):
+        pass
+
+    def _onGlobalContainerChanged(self):
+        self._global_container_stack = Application.getInstance().getGlobalContainerStack()
+
+    @staticmethod
+    def createSettingInheritanceManager(engine=None, script_engine=None):
+        return SettingInheritanceManager()