typing

src/bonsai/bonsai/bim/module/drawing/__init__.py

@@ -100,7 +100,7 @@ classes = (
     prop.Sheet,
     prop.DocProperties,
     prop.BIMCameraProperties,
-    prop.Literal,
+    prop.LiteralProps,
     prop.BIMTextProperties,
     prop.BIMAssignedProductProperties,
     prop.BIMAnnotationProperties,

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

@@ -1686,7 +1686,7 @@ class RemoveDrawingFromSheet(bpy.types.Operator, tool.Ifc.Operator):
             return False
 
         if active_item.reference_type == "TITLEBLOCK":
-            cls.poll_message_set("No effect deleting this.")
+            cls.poll_message_set("No effect deleting titleblock reference.")
             return False
         return True
 

src/bonsai/bonsai/bim/module/drawing/prop.py

@@ -44,6 +44,7 @@ from bpy.props import (
     CollectionProperty,
     BoolVectorProperty,
 )
+from typing import TYPE_CHECKING, Literal
 
 
 diagram_scales_enum = []
@@ -294,12 +295,25 @@ class Drawing(PropertyGroup):
     is_drawing: BoolProperty(name="Is Drawing", default=False)
     is_expanded: BoolProperty(name="Is Expanded", default=True)
 
+    if TYPE_CHECKING:
+        ifc_definition_id: int
+        name: str
+        target_view: str
+        is_selected: bool
+        is_drawing: bool
+        is_expanded: bool
+
 
 class Document(PropertyGroup):
     ifc_definition_id: IntProperty(name="IFC Definition ID")
     name: StringProperty(name="Name", update=update_document_name)
     identification: StringProperty(name="Identification")
 
+    if TYPE_CHECKING:
+        ifc_definition_id: int
+        name: str
+        identification: str
+
 
 class Sheet(PropertyGroup):
     ifc_definition_id: IntProperty(name="IFC Definition ID")
@@ -310,6 +324,15 @@ class Sheet(PropertyGroup):
     reference_type: StringProperty(name="Reference Type")
     is_expanded: BoolProperty(name="Is Expanded", default=False)
 
+    if TYPE_CHECKING:
+        ifc_definition_id: int
+        identification: str
+        name: str
+        is_sheet: bool
+        is_selected: bool
+        reference_type: str
+        is_expanded: bool
+
 
 class DrawingStyle(PropertyGroup):
     name: StringProperty(name="Name", get=get_drawing_style_name, set=set_drawing_style_name)
@@ -408,6 +431,47 @@ class DocProperties(PropertyGroup):
         description="Upon import, these classes will display as wireframe.\nEx: IfcVirtualelement, IfcSpace",
     )
 
+    if TYPE_CHECKING:
+        should_use_underlay_cache: bool
+        should_use_linework_cache: bool
+        should_use_annotation_cache: bool
+        is_editing_drawings: bool
+        is_editing_schedules: bool
+        is_editing_references: bool
+        target_view: Literal["PLAN_VIEW", "ELEVATION_VIEW", "SECTION_VIEW", "REFLECTED_PLAN_VIEW", "MODEL_VIEW"]
+        location_hint: str
+        drawings: bpy.types.bpy_prop_collection_idprop[Drawing]
+        active_drawing_id: int
+        active_drawing_index: int
+        current_drawing_index: int
+        schedules: bpy.types.bpy_prop_collection_idprop[Document]
+        active_schedule_index: int
+        references: bpy.types.bpy_prop_collection_idprop[Document]
+        active_reference_index: int
+        titleblock: str
+        is_editing_sheets: bool
+        sheets: bpy.types.bpy_prop_collection_idprop[Sheet]
+        active_sheet_index: int
+        ifc_files: bpy.types.bpy_prop_collection_idprop[StrProperty]
+        drawing_styles: bpy.types.bpy_prop_collection_idprop[DrawingStyle]
+        should_draw_decorations: bool
+        sheets_dir: str
+        layouts_dir: str
+        titleblocks_dir: str
+        drawings_dir: str
+        stylesheet_path: str
+        schedules_stylesheet_path: str
+        markers_path: str
+        symbols_path: str
+        patterns_path: str
+        shadingstyles_path: str
+        shadingstyle_default: str
+        drawing_font: str
+        magic_font_scale: float
+        imperial_precision: str
+        tolerance: float
+        classes_to_wireframe: str
+
 
 class BIMCameraProperties(PropertyGroup):
     linework_mode: EnumProperty(
@@ -490,7 +554,7 @@ BOX_ALIGNMENT_POSITIONS = [
 ]
 
 
-class Literal(PropertyGroup):
+class LiteralProps(PropertyGroup):
     def set_box_alignment(self, new_value):
         markers = new_value.count(True)
         if not markers:
@@ -535,7 +599,7 @@ class Literal(PropertyGroup):
 
 class BIMTextProperties(PropertyGroup):
     is_editing: BoolProperty(name="Is Editing", default=False)
-    literals: CollectionProperty(name="Literals", type=Literal)
+    literals: CollectionProperty(name="Literals", type=LiteralProps)
     font_size: EnumProperty(
         items=[
             ("1.8", "1.8 - Small", ""),

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

@@ -1075,7 +1075,7 @@ class OverrideDuplicateMove(bpy.types.Operator):
 
     @staticmethod
     def duplicate_item(obj: bpy.types.Object) -> None:
-        props = bpy.context.scene.BIMGeometryProperties
+        props = tool.Geometry.get_geometry_props()
         item = tool.Ifc.get().by_id(obj.data.BIMMeshProperties.ifc_definition_id)
         new_item = ifcopenshell.util.element.copy_deep(tool.Ifc.get(), item)
         new_obj = obj.copy()
@@ -2750,17 +2750,17 @@ class ImportRepresentationItems(bpy.types.Operator, tool.Ifc.Operator):
     def _execute(self, context):
         obj = context.active_object
         assert obj
-        props = context.scene.BIMGeometryProperties
+        props = tool.Geometry.get_geometry_props()
         if previous_obj := props.representation_obj:
             previous_obj.hide_set(False)
         props.representation_obj = obj
         obj.hide_set(True)
         tool.Geometry.lock_object(obj)
 
-        context.scene.BIMGeometryProperties.is_changing_mode = True
-        if context.scene.BIMGeometryProperties.mode != "ITEM":
-            context.scene.BIMGeometryProperties.mode = "ITEM"
-        context.scene.BIMGeometryProperties.is_changing_mode = False
+        props.is_changing_mode = True
+        if props.mode != "ITEM":
+            props.mode = "ITEM"
+        props.is_changing_mode = False
 
         tool.Loader.load_settings()
 

src/bonsai/bonsai/bim/module/geometry/prop.py

@@ -32,7 +32,7 @@ from bpy.props import (
     FloatVectorProperty,
     CollectionProperty,
 )
-from typing import Optional, TYPE_CHECKING
+from typing import Optional, TYPE_CHECKING, Union
 
 
 def get_contexts(self, context):
@@ -302,3 +302,13 @@ class BIMGeometryProperties(PropertyGroup):
         type=bpy.types.Object,
         poll=is_object_valid_for_representation_copy,
     )
+
+    if TYPE_CHECKING:
+        should_use_presentation_style_assignment: bool
+        should_force_faceted_brep: bool
+        should_force_triangulation: bool
+        is_changing_mode: bool
+        mode: str
+        representation_obj: Union[bpy.types.Object, None]
+        item_objs: bpy.types.bpy_prop_collection_idprop[RepresentationItemObject]
+        representation_from_object: Union[bpy.types.Object, None]

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

@@ -1243,7 +1243,7 @@ class LoadLink(bpy.types.Operator):
             os.remove(blend_filepath)
 
         if not blend_filepath.exists():
-            pprops = bpy.context.scene.BIMProjectProperties
+            pprops = tool.Project.get_project_props()
             gprops = bpy.context.scene.BIMGeoreferenceProperties
 
             code = f"""

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

@@ -337,7 +337,7 @@ class LoadZones(bpy.types.Operator):
     bl_options = {"REGISTER", "UNDO"}
 
     def _execute(self, context):
-        props = bpy.context.scene.BIMZoneProperties
+        props = tool.System.get_zone_props()
         props.zones.clear()
         for zone in tool.Ifc.get().by_type("IfcZone"):
             new = props.zones.add()
@@ -354,7 +354,7 @@ class UnloadZones(bpy.types.Operator):
     bl_options = {"REGISTER", "UNDO"}
 
     def _execute(self, context):
-        props = bpy.context.scene.BIMZoneProperties
+        props = tool.System.get_zone_props()
         props.is_loaded = False
         return {"FINISHED"}
 
@@ -386,7 +386,7 @@ class EnableEditingZone(bpy.types.Operator):
     zone: bpy.props.IntProperty()
 
     def execute(self, context):
-        props = bpy.context.scene.BIMZoneProperties
+        props = tool.System.get_zone_props()
         props.attributes.clear()
         bonsai.bim.helper.import_attributes2(tool.Ifc.get().by_id(self.zone), props.attributes)
         props.is_editing = self.zone
@@ -399,7 +399,7 @@ class DisableEditingZone(bpy.types.Operator, tool.Ifc.Operator):
     bl_options = {"REGISTER", "UNDO"}
 
     def execute(self, context):
-        props = bpy.context.scene.BIMZoneProperties
+        props = tool.System.get_zone_props()
         props.is_editing = 0
         return {"FINISHED"}
 
@@ -410,7 +410,7 @@ class EditZone(bpy.types.Operator, tool.Ifc.Operator):
     bl_options = {"REGISTER", "UNDO"}
 
     def _execute(self, context):
-        props = bpy.context.scene.BIMZoneProperties
+        props = tool.System.get_zone_props()
         zone = tool.Ifc.get().by_id(props.is_editing)
         attributes = bonsai.bim.helper.export_attributes(props.attributes)
         ifcopenshell.api.run("system.edit_system", tool.Ifc.get(), system=zone, attributes=attributes)

src/bonsai/bonsai/bim/module/system/prop.py

@@ -31,6 +31,7 @@ from bpy.props import (
     FloatVectorProperty,
     CollectionProperty,
 )
+from typing import TYPE_CHECKING
 
 
 def get_system_class(self, context):
@@ -71,6 +72,17 @@ class BIMSystemProperties(PropertyGroup):
         name="Should Draw Decorations", description="Toggle system decorations", update=toggle_decorations
     )
 
+    if TYPE_CHECKING:
+        system_attributes: bpy.types.bpy_prop_collection_idprop[Attribute]
+        is_editing: bool
+        is_adding: bool
+        systems: bpy.types.bpy_prop_collection_idprop[System]
+        active_system_index: int
+        active_system_id: int
+        edited_system_id: int
+        system_class: str
+        should_draw_decorations: bool
+
 
 class BIMZoneProperties(PropertyGroup):
     attributes: CollectionProperty(name="Attributes", type=Attribute)
@@ -78,3 +90,10 @@ class BIMZoneProperties(PropertyGroup):
     is_editing: IntProperty(name="Is Editing", default=0)
     zones: CollectionProperty(name="Zones", type=Zone)
     active_zone_index: IntProperty(name="Active Zone Index")
+
+    if TYPE_CHECKING:
+        attributes: bpy.types.bpy_prop_collection_idprop[Attribute]
+        is_loaded: bool
+        is_editing: int
+        zones: bpy.types.bpy_prop_collection_idprop[Zone]
+        active_zone_index: int

src/bonsai/bonsai/bim/module/system/ui.py

@@ -350,7 +350,7 @@ class BIM_PT_zones(Panel):
     def draw(self, context):
         if not ZonesData.is_loaded:
             ZonesData.load()
-        self.props = context.scene.BIMZoneProperties
+        self.props = tool.System.get_zone_props()
 
         row = self.layout.row(align=True)
         row.label(text="{} Zones Found".format(ZonesData.data["total_zones"]), icon="SEQ_STRIP_META")
@@ -394,7 +394,7 @@ class BIM_PT_active_object_zones(Panel):
     def draw(self, context):
         if not ActiveObjectZonesData.is_loaded:
             ActiveObjectZonesData.load()
-        self.props = context.scene.BIMZoneProperties
+        self.props = tool.System.get_zone_props()
 
         for zone in ActiveObjectZonesData.data["zones"]:
             row = self.layout.row()

src/bonsai/bonsai/core/system.py

@@ -16,58 +16,68 @@
 # You should have received a copy of the GNU General Public License
 # along with Bonsai.  If not, see <http://www.gnu.org/licenses/>.
 
+from __future__ import annotations
+from typing import TYPE_CHECKING, Optional
 
-def load_systems(system):
+if TYPE_CHECKING:
+    import bpy
+    import ifcopenshell
+    import bonsai.tool as tool
+
+
+def load_systems(system: tool.System) -> None:
     system.import_systems()
     system.enable_system_editing_ui()
     system.disable_editing_system()
 
 
-def disable_system_editing_ui(system):
+def disable_system_editing_ui(system: tool.System) -> None:
     system.disable_editing_system()
     system.disable_system_editing_ui()
 
 
-def add_system(ifc, system, ifc_class=None):
+def add_system(ifc: tool.Ifc, system: tool.System, ifc_class: str) -> None:
     ifc.run("system.add_system", ifc_class=ifc_class)
     system.import_systems()
 
 
-def edit_system(ifc, system_tool, system=None):
+def edit_system(ifc: tool.Ifc, system_tool: tool.System, system: ifcopenshell.entity_instance) -> None:
     attributes = system_tool.export_system_attributes()
     ifc.run("system.edit_system", system=system, attributes=attributes)
     system_tool.disable_editing_system()
     system_tool.import_systems()
 
 
-def remove_system(ifc, system_tool, system=None):
+def remove_system(ifc: tool.Ifc, system_tool: tool.System, system: ifcopenshell.entity_instance) -> None:
     ifc.run("system.remove_system", system=system)
     system_tool.import_systems()
 
 
-def enable_editing_system(system_tool, system=None):
+def enable_editing_system(system_tool: tool.System, system: ifcopenshell.entity_instance) -> None:
     system_tool.import_system_attributes(system)
     system_tool.set_active_edited_system(system)
 
 
-def disable_editing_system(system):
+def disable_editing_system(system: tool.System) -> None:
     system.disable_editing_system()
 
 
-def assign_system(ifc, system=None, product=None):
+def assign_system(ifc: tool.Ifc, system: ifcopenshell.entity_instance, product: ifcopenshell.entity_instance) -> None:
     ifc.run("system.assign_system", products=[product], system=system)
 
 
-def unassign_system(ifc, system=None, product=None):
+def unassign_system(ifc: tool.Ifc, system: ifcopenshell.entity_instance, product: ifcopenshell.entity_instance) -> None:
     ifc.run("system.unassign_system", products=[product], system=system)
 
 
-def select_system_products(system_tool, system=None):
+def select_system_products(system_tool: tool.System, system: ifcopenshell.entity_instance) -> None:
     system_tool.select_system_products(system)
     system_tool.set_active_system(system)
 
 
-def show_ports(ifc, system, spatial, element=None):
+def show_ports(
+    ifc: tool.Ifc, system: tool.System, spatial: tool.Spatial, element: ifcopenshell.entity_instance
+) -> None:
     obj = ifc.get_object(element)
     if obj and ifc.is_moved(obj):
         system.run_geometry_edit_object_placement(obj=obj)
@@ -77,7 +87,7 @@ def show_ports(ifc, system, spatial, element=None):
     spatial.select_products(ports)
 
 
-def hide_ports(ifc, system, element=None):
+def hide_ports(ifc: tool.Ifc, system: tool.System, element: ifcopenshell.entity_instance) -> None:
     obj = ifc.get_object(element)
     if obj and ifc.is_moved(obj):
         system.run_geometry_edit_object_placement(obj=obj)
@@ -91,27 +101,27 @@ def hide_ports(ifc, system, element=None):
     system.delete_element_objects(ports)
 
 
-def add_port(ifc, system, element=None):
+def add_port(ifc: tool.Ifc, system: tool.System, element: ifcopenshell.entity_instance) -> None:
     system.load_ports(element, system.get_ports(element))
     obj = system.create_empty_at_cursor_with_element_orientation(element)
     port = system.run_root_assign_class(obj=obj, ifc_class="IfcDistributionPort", should_add_representation=False)
     ifc.run("system.assign_port", element=element, port=port)
 
 
-def remove_port(ifc, system, port=None):
+def remove_port(ifc: tool.Ifc, system: tool.System, port: ifcopenshell.entity_instance) -> None:
     system.delete_element_objects([port])
     ifc.run("root.remove_product", product=port)
 
 
-def connect_port(ifc, port1=None, port2=None):
+def connect_port(ifc: tool.Ifc, port1: ifcopenshell.entity_instance, port2: ifcopenshell.entity_instance) -> None:
     ifc.run("system.connect_port", port1=port1, port2=port2)
 
 
-def disconnect_port(ifc, port=None):
+def disconnect_port(ifc: tool.Ifc, port: ifcopenshell.entity_instance) -> None:
     ifc.run("system.disconnect_port", port=port)
 
 
-def set_flow_direction(ifc, system, port=None, direction=None):
+def set_flow_direction(ifc: tool.Ifc, system: tool.System, port: ifcopenshell.entity_instance, direction: str) -> None:
     port2 = system.get_connected_port(port)
     if not port2:
         return

src/bonsai/bonsai/tool/drawing.py

@@ -16,6 +16,7 @@
 # You should have received a copy of the GNU General Public License
 # along with Bonsai.  If not, see <http://www.gnu.org/licenses/>.
 
+from __future__ import annotations
 import os
 import re
 import collections
@@ -34,6 +35,7 @@ import subprocess
 import numpy as np
 import bonsai.core.tool
 import bonsai.core.geometry
+import bonsai.core.type
 import bonsai.tool as tool
 import ifcopenshell.api
 import ifcopenshell.api.document
@@ -49,9 +51,13 @@ from shapely.ops import unary_union
 from lxml import etree
 from mathutils import Vector, Matrix
 from fractions import Fraction
-from typing import Optional, Union, Iterable, Any, Literal, Sequence
+from typing import Optional, Union, Iterable, Any, Literal, Sequence, TYPE_CHECKING
 from pathlib import Path
 
+if TYPE_CHECKING:
+    from bonsai.bim.module.drawing.prop import DocProperties, Sheet
+    from bonsai.bim.module.drawing.prop import Drawing as DrawingProperties
+
 
 class Drawing(bonsai.core.tool.Drawing):
     ANNOTATION_DATA_TYPE = Literal["empty", "curve", "mesh"]
@@ -81,6 +87,10 @@ class Drawing(bonsai.core.tool.Drawing):
     }
     # fmt: on
 
+    @classmethod
+    def get_document_props(cls) -> DocProperties:
+        return bpy.context.scene.DocProperties
+
     @classmethod
     def canonicalise_class_name(cls, name: str) -> str:
         return re.sub("[^0-9a-zA-Z]+", "", name)
@@ -820,7 +830,7 @@ class Drawing(bonsai.core.tool.Drawing):
 
     @classmethod
     def import_documents(cls, document_type: DOCUMENT_TYPE) -> None:
-        dprops = bpy.context.scene.DocProperties
+        dprops = cls.get_document_props()
         if document_type == "SCHEDULE":
             documents_collection = dprops.schedules
         elif document_type == "REFERENCE":
@@ -839,7 +849,7 @@ class Drawing(bonsai.core.tool.Drawing):
 
     @classmethod
     def import_sheets(cls) -> None:
-        props = bpy.context.scene.DocProperties
+        props = cls.get_document_props()
         expanded_sheets = {s.ifc_definition_id for s in props.sheets if s.is_expanded}
         if not hasattr(cls, "sheet_selected_states"):
             cls.sheet_selected_states = {}
@@ -879,13 +889,13 @@ class Drawing(bonsai.core.tool.Drawing):
                 new.reference_type = reference_description
 
     @classmethod
-    def get_active_sheet(cls, context: bpy.types.Context) -> bpy.types.PropertyGroup:
-        props = context.scene.DocProperties
+    def get_active_sheet(cls, context: bpy.types.Context) -> Sheet:
+        props = cls.get_document_props()
         return next(s for s in props.sheets[: props.active_sheet_index + 1][::-1] if s.is_sheet)
 
     @classmethod
-    def get_active_drawing_item(cls) -> Union[bpy.types.PropertyGroup, None]:
-        props = bpy.context.scene.DocProperties
+    def get_active_drawing_item(cls) -> Union[DrawingProperties, None]:
+        props = cls.get_document_props()
         drawing_index = props.active_drawing_index
         if len(props.drawings) > drawing_index >= 0:
             item = props.drawings[drawing_index]
@@ -893,10 +903,8 @@ class Drawing(bonsai.core.tool.Drawing):
                 return item
 
     @classmethod
-    def get_active_sheet_item(
-        cls, *, is_sheet: bool = False, reference_type: str = ""
-    ) -> Union[bpy.types.PropertyGroup, None]:
-        props = bpy.context.scene.DocProperties
+    def get_active_sheet_item(cls, *, is_sheet: bool = False, reference_type: str = "") -> Union[Sheet, None]:
+        props = cls.get_document_props()
         sheet_index = props.active_sheet_index
         if len(props.sheets) > sheet_index >= 0:
             item = props.sheets[sheet_index]

src/bonsai/bonsai/tool/geometry.py

@@ -57,10 +57,14 @@ from typing_extensions import TypeIs
 
 if TYPE_CHECKING:
     from bonsai.bim.prop import Attribute
-    from bonsai.bim.module.geometry.prop import BIMObjectGeometryProperties
+    from bonsai.bim.module.geometry.prop import BIMObjectGeometryProperties, BIMGeometryProperties
 
 
 class Geometry(bonsai.core.tool.Geometry):
+    @classmethod
+    def get_geometry_props(cls) -> BIMGeometryProperties:
+        return bpy.context.scene.BIMGeometryProperties
+
     @classmethod
     def get_object_geometry_props(cls, object: bpy.types.Object) -> BIMObjectGeometryProperties:
         return object.BIMGeometryProperties

src/bonsai/bonsai/tool/system.py

@@ -16,6 +16,7 @@
 # You should have received a copy of the GNU General Public License
 # along with Bonsai.  If not, see <http://www.gnu.org/licenses/>.
 
+from __future__ import annotations
 import bpy
 import ifcopenshell.util.element
 import ifcopenshell.util.system
@@ -31,11 +32,30 @@ from mathutils import Matrix, Vector
 from bonsai.bim.module.system.data import ObjectSystemData, SystemDecorationData
 from bonsai.bim.module.drawing.decoration import profile_consequential
 from enum import Enum
+from typing import TYPE_CHECKING, Optional, Any, Union
+
+if TYPE_CHECKING:
+    from bonsai.bim.module.system.prop import BIMSystemProperties, BIMZoneProperties
 
 
 class System(bonsai.core.tool.System):
     @classmethod
-    def add_ports(cls, obj, add_start_port=True, add_end_port=True, end_port_pos=None, offset_end_port=None):
+    def get_system_props(cls) -> BIMSystemProperties:
+        return bpy.context.scene.BIMSystemProperties
+
+    @classmethod
+    def get_zone_props(cls) -> BIMZoneProperties:
+        return bpy.context.scene.BIMZoneProperties
+
+    @classmethod
+    def add_ports(
+        cls,
+        obj: bpy.types.Object,
+        add_start_port: bool = True,
+        add_end_port: bool = True,
+        end_port_pos: Optional[Vector] = None,
+        offset_end_port: Optional[Vector] = None,
+    ) -> list[ifcopenshell.entity_instance]:
         def add_port(mep_element, matrix):
             port = tool.Ifc.run("system.add_port", element=mep_element)
             port.FlowDirection = "NOTDEFINED"
@@ -66,7 +86,7 @@ class System(bonsai.core.tool.System):
         return ports
 
     @classmethod
-    def create_empty_at_cursor_with_element_orientation(cls, element):
+    def create_empty_at_cursor_with_element_orientation(cls, element: ifcopenshell.entity_instance) -> bpy.types.Object:
         element_obj = tool.Ifc.get_object(element)
         obj = bpy.data.objects.new("Port", None)
         obj.matrix_world = element_obj.matrix_world
@@ -75,38 +95,38 @@ class System(bonsai.core.tool.System):
         return obj
 
     @classmethod
-    def delete_element_objects(cls, elements):
+    def delete_element_objects(cls, elements: list[ifcopenshell.entity_instance]) -> None:
         for element in elements:
             obj = tool.Ifc.get_object(element)
             if obj:
                 bpy.data.objects.remove(obj)
 
     @classmethod
-    def disable_editing_system(cls):
-        bpy.context.scene.BIMSystemProperties.edited_system_id = 0
+    def disable_editing_system(cls) -> None:
+        cls.get_system_props().edited_system_id = 0
 
     @classmethod
-    def disable_system_editing_ui(cls):
-        bpy.context.scene.BIMSystemProperties.is_editing = False
+    def disable_system_editing_ui(cls) -> None:
+        cls.get_system_props().is_editing = False
 
     @classmethod
-    def enable_system_editing_ui(cls):
-        bpy.context.scene.BIMSystemProperties.is_editing = True
+    def enable_system_editing_ui(cls) -> None:
+        cls.get_system_props().is_editing = True
 
     @classmethod
-    def export_system_attributes(cls):
-        return bonsai.bim.helper.export_attributes(bpy.context.scene.BIMSystemProperties.system_attributes)
+    def export_system_attributes(cls) -> dict[str, Any]:
+        return bonsai.bim.helper.export_attributes(cls.get_system_props().system_attributes)
 
     @classmethod
-    def get_connected_port(cls, port):
+    def get_connected_port(cls, port: ifcopenshell.entity_instance) -> Union[ifcopenshell.entity_instance, None]:
         return ifcopenshell.util.system.get_connected_port(port)
 
     @classmethod
-    def get_ports(cls, element):
+    def get_ports(cls, element: ifcopenshell.entity_instance) -> list[ifcopenshell.entity_instance]:
         return ifcopenshell.util.system.get_ports(element)
 
     @classmethod
-    def get_port_relating_element(cls, port):
+    def get_port_relating_element(cls, port: ifcopenshell.entity_instance) -> ifcopenshell.entity_instance:
         if tool.Ifc.get_schema() == "IFC2X3":
             element = port.ContainedIn[0].RelatedElement
         else:
@@ -114,7 +134,7 @@ class System(bonsai.core.tool.System):
         return element
 
     @classmethod
-    def get_port_predefined_type(cls, mep_element):
+    def get_port_predefined_type(cls, mep_element: ifcopenshell.entity_instance) -> str:
         split_camel_case = lambda x: re.findall("[A-Z][^A-Z]*", x)
         mep_class = mep_element.is_a()
         if mep_class.endswith("Type"):
@@ -125,20 +145,20 @@ class System(bonsai.core.tool.System):
         return class_name
 
     @classmethod
-    def import_system_attributes(cls, system):
-        props = bpy.context.scene.BIMSystemProperties
+    def import_system_attributes(cls, system: ifcopenshell.entity_instance) -> None:
+        props = cls.get_system_props()
         props.system_attributes.clear()
         bonsai.bim.helper.import_attributes2(system, props.system_attributes)
 
     @classmethod
-    def get_systems(cls):
+    def get_systems(cls) -> list[ifcopenshell.entity_instance]:
         if tool.Ifc.get_schema() == "IFC2X3":
             return tool.Ifc.get().by_type("IfcSystem") + tool.Ifc.get().by_type("IfcZone")
         return tool.Ifc.get().by_type("IfcSystem")
 
     @classmethod
-    def import_systems(cls):
-        props = bpy.context.scene.BIMSystemProperties
+    def import_systems(cls) -> None:
+        props = cls.get_system_props()
         props.systems.clear()
         for system in cls.get_systems():
             if system.is_a() in ["IfcStructuralAnalysisModel"]:
@@ -179,7 +199,7 @@ class System(bonsai.core.tool.System):
             port_obj.matrix_parent_inverse = obj.matrix_world.inverted()
 
     @classmethod
-    def run_geometry_edit_object_placement(cls, obj=None):
+    def run_geometry_edit_object_placement(cls, obj: bpy.types.Object) -> None:
         return bonsai.core.geometry.edit_object_placement(tool.Ifc, tool.Geometry, tool.Surveyor, obj=obj)
 
     @classmethod
@@ -205,24 +225,24 @@ class System(bonsai.core.tool.System):
         )
 
     @classmethod
-    def select_system_products(cls, system):
+    def select_system_products(cls, system: ifcopenshell.entity_instance) -> None:
         tool.Spatial.select_products(ifcopenshell.util.system.get_system_elements(system))
 
     @classmethod
-    def set_active_edited_system(cls, system):
-        bpy.context.scene.BIMSystemProperties.edited_system_id = system.id()
+    def set_active_edited_system(cls, system: ifcopenshell.entity_instance) -> None:
+        cls.get_system_props().edited_system_id = system.id()
 
     @classmethod
-    def set_active_system(cls, system):
-        bpy.context.scene.BIMSystemProperties.active_system_id = system.id()
+    def set_active_system(cls, system: ifcopenshell.entity_instance) -> None:
+        cls.get_system_props().active_system_id = system.id()
 
     @classmethod
-    def get_active_system(cls):
-        system_props = bpy.context.scene.BIMSystemProperties
+    def get_active_system(cls) -> Union[ifcopenshell.entity_instance, None]:
+        system_props = cls.get_system_props()
         return tool.Ifc.get_entity_by_id(system_props.active_system_id)
 
     @classmethod
-    def get_decoration_data(cls):
+    def get_decoration_data(cls) -> dict[str, Any]:
         all_vertices = []
         preview_edges = []
         special_vertices = []
@@ -367,7 +387,11 @@ class System(bonsai.core.tool.System):
         return decoration_data
 
     @classmethod
-    def get_connected_elements(cls, element, traversed_elements=None):
+    def get_connected_elements(
+        cls,
+        element: ifcopenshell.entity_instance,
+        traversed_elements: Optional[set[ifcopenshell.entity_instance]] = None,
+    ) -> set[ifcopenshell.entity_instance]:
         """Recursively retrieves all connected elements to the given `element`.
 
         `traversed_elements` is a set to store connected elements fetched recursively,
@@ -387,17 +411,19 @@ class System(bonsai.core.tool.System):
         return traversed_elements
 
     @classmethod
-    def is_mep_element(cls, element):
+    def is_mep_element(cls, element: ifcopenshell.entity_instance) -> bool:
         return element.is_a("IfcFlowSegment") or element.is_a("IfcFlowFitting")
 
     @classmethod
-    def get_flow_element_controls(cls, element):
+    def get_flow_element_controls(cls, element: ifcopenshell.entity_instance) -> list[ifcopenshell.entity_instance]:
         if not element.HasControlElements:
             return []
         return [control for control in element.HasControlElements[0].RelatedControlElements]
 
     @classmethod
-    def get_flow_control_flow_element(cls, element):
+    def get_flow_control_flow_element(
+        cls, element: ifcopenshell.entity_instance
+    ) -> Union[ifcopenshell.entity_instance, None]:
         if not element.AssignedToFlowElement:
             return
         return element.AssignedToFlowElement[0].RelatingFlowElement