fix broken enum after removing pset template/file

src/bonsai/bonsai/bim/module/pset_template/operator.py

@@ -101,16 +101,18 @@ class RemovePsetTemplate(bpy.types.Operator, PsetTemplateOperator):
 
     def _execute(self, context):
         props = context.scene.BIMPsetTemplateProperties
-        if props.active_pset_template_id == int(props.pset_templates):
+        current_pset_template_id = int(props.pset_templates)
+        if props.active_pset_template_id == current_pset_template_id:
             bpy.ops.bim.disable_editing_pset_template()
         ifcopenshell.api.run(
             "pset_template.remove_pset_template",
             self.template_file,
-            **{"pset_template": self.template_file.by_id(int(props.pset_templates))}
+            **{"pset_template": self.template_file.by_id(current_pset_template_id)}
         )
         self.template_file.write(IfcStore.pset_template_path)
         bonsai.bim.handler.refresh_ui_data()
         bonsai.bim.schema.reload(tool.Ifc.get().schema)
+        tool.Blender.ensure_enum_is_valid(props, "pset_templates")
 
 
 class EnableEditingPsetTemplate(bpy.types.Operator):
@@ -250,8 +252,18 @@ class RemovePsetTemplateFile(bpy.types.Operator):
             pass
         bonsai.bim.handler.refresh_ui_data()
         bonsai.bim.schema.reload(tool.Ifc.get().schema)
+
+        # Ensure enum is valid after deletion.
+        self.props = context.scene.BIMPsetTemplateProperties
+        if not tool.Blender.ensure_enum_is_valid(self.props, "pset_template_files"):
+            self.update_template_files_prop(context)
         return {"FINISHED"}
 
+    def update_template_files_prop(self, context: bpy.types.Context) -> None:
+        import bonsai.bim.module.pset_template.prop
+
+        bonsai.bim.module.pset_template.prop.updatePsetTemplateFiles(self.props, context)
+
 
 class AddPropTemplate(bpy.types.Operator, PsetTemplateOperator):
     bl_idname = "bim.add_prop_template"

src/bonsai/bonsai/tool/blender.py

@@ -594,6 +594,33 @@ class Blender(bonsai.core.tool.Blender):
             return items[index][0]
         return None
 
+    @classmethod
+    def ensure_enum_is_valid(cls, props: bpy.types.PropertyGroup, prop_name: str) -> bool:
+        """Ensure that enum is valid after current enum item was deleted.
+
+        :return: True if enum is valid and update callback was triggered,
+            False if enum is still invalid (as there no enum items)
+            and update callback was not triggered (may need to trigger it manually).
+        """
+        current_value = tool.Blender.get_enum_safe(props, prop_name)
+        if current_value is not None:
+            # Value is valid, just trigger the update callback.
+            setattr(props, prop_name, current_value)
+            return True
+
+        # If enum was never changed prop_name won't be present in props
+        # and implicit 0 index is assumed.
+        current_index = props.get(prop_name, 0)
+        # Index is still invalid and triggering update callback directly
+        # will cause an error, so we just stop here.
+        if current_index == 0:
+            return False
+
+        props[prop_name] = current_index - 1
+        # Trigger update callback.
+        setattr(props, prop_name, getattr(props, prop_name))
+        return True
+
     @classmethod
     def append_data_block(cls, filepath: str, data_block_type: str, name: str, link=False, relative=False) -> dict:
         if Path(filepath) == Path(bpy.data.filepath):