From 248dab936d83e9357da6535e8101a005ea15f8bb Mon Sep 17 00:00:00 2001
From: Dion Moult <dion@thinkmoult.com>
Date: Mon, 24 Oct 2022 13:36:50 +1100
Subject: [PATCH] Experimental reimplementation of reloading an updated IFC

---
 src/blenderbim/blenderbim/bim/ifc.py      | 10 +++-
 src/blenderbim/blenderbim/bim/operator.py | 72 +++++++++++++++++++++--
 2 files changed, 76 insertions(+), 6 deletions(-)

diff --git a/src/blenderbim/blenderbim/bim/ifc.py b/src/blenderbim/blenderbim/bim/ifc.py
index 73be9ca371..b24ec89408 100644
--- a/src/blenderbim/blenderbim/bim/ifc.py
+++ b/src/blenderbim/blenderbim/bim/ifc.py
@@ -252,13 +252,19 @@ class IfcStore:
         if not obj:
             return
         if obj.BIMObjectProperties.ifc_definition_id:
-            element = IfcStore.get_file().by_id(obj.BIMObjectProperties.ifc_definition_id)
+            try:
+                element = IfcStore.get_file().by_id(obj.BIMObjectProperties.ifc_definition_id)
+            except:
+                return
             data = {"id": element.id(), "obj": obj.name}
             if hasattr(element, "GlobalId"):
                 data["guid"] = element.GlobalId
             IfcStore.commit_link_element(data)
         if hasattr(obj, "BIMMaterialProperties") and obj.BIMMaterialProperties.ifc_style_id:
-            element = IfcStore.get_file().by_id(obj.BIMMaterialProperties.ifc_style_id)
+            try:
+                element = IfcStore.get_file().by_id(obj.BIMMaterialProperties.ifc_style_id)
+            except:
+                return
             data = {"id": element.id(), "obj": obj.name}
             IfcStore.commit_link_element(data)
 
diff --git a/src/blenderbim/blenderbim/bim/operator.py b/src/blenderbim/blenderbim/bim/operator.py
index 671a7eb492..5097257704 100644
--- a/src/blenderbim/blenderbim/bim/operator.py
+++ b/src/blenderbim/blenderbim/bim/operator.py
@@ -19,11 +19,14 @@
 import os
 import bpy
 import json
+import time
+import logging
 import webbrowser
 import ifcopenshell
 import blenderbim.bim.handler
 import blenderbim.tool as tool
 from . import schema
+from blenderbim.bim import import_ifc
 from blenderbim.bim.ifc import IfcStore
 from blenderbim.bim.prop import StrProperty
 from blenderbim.bim.ui import IFCFileSelector
@@ -397,16 +400,77 @@ class BIM_OT_remove_section_plane(bpy.types.Operator):
         bpy.ops.object.delete({"selected_objects": [context.active_object]})
 
 
-class ReloadIfcFile(bpy.types.Operator):
+class ReloadIfcFile(bpy.types.Operator, tool.Ifc.Operator):
     bl_idname = "bim.reload_ifc_file"
     bl_label = "Reload IFC File"
     bl_options = {"REGISTER", "UNDO"}
-    bl_description = "Reload the same IFC file"
+    bl_description = "Reload an updated IFC file"
+    filepath: bpy.props.StringProperty(subtype="FILE_PATH")
+    filter_glob: bpy.props.StringProperty(default="*.ifc", options={"HIDDEN"})
 
-    def execute(self, context):
-        # TODO: reimplement. See #1222.
+    def _execute(self, context):
+        import ifcdiff
+
+        old = tool.Ifc.get()
+        new = ifcopenshell.open(self.filepath)
+
+        ifc_diff = ifcdiff.IfcDiff(old, new, relationships=[])
+        ifc_diff.diff()
+
+        changed_elements = set([k for k, v in ifc_diff.change_register.items() if "geometry_changed" in v])
+
+        for global_id in ifc_diff.deleted_elements | changed_elements:
+            element = tool.Ifc.get().by_guid(global_id)
+            obj = tool.Ifc.get_object(element)
+            if obj:
+                bpy.data.objects.remove(obj)
+
+        # STEP IDs may change, but we assume the GlobalID to be constant
+        obj_map = {}
+        for obj in bpy.data.objects:
+            element = tool.Ifc.get_entity(obj)
+            if element and hasattr(element, "GlobalId"):
+                obj_map[obj.name] = element.GlobalId
+
+        delta_elements = [new.by_guid(global_id) for global_id in ifc_diff.added_elements | changed_elements]
+        tool.Ifc.set(new)
+
+        for obj in bpy.data.objects:
+            global_id = obj_map.get(obj.name)
+            if global_id:
+                try:
+                    tool.Ifc.link(new.by_guid(global_id), obj)
+                except:
+                    # Still prototyping, so things like types definitely won't work
+                    print("Could not relink", obj)
+
+        start = time.time()
+        logger = logging.getLogger("ImportIFC")
+        path_log = os.path.join(context.scene.BIMProperties.data_dir, "process.log")
+        if not os.access(context.scene.BIMProperties.data_dir, os.W_OK):
+            path_log = os.path.join(tempfile.mkdtemp(), "process.log")
+        logging.basicConfig(
+            filename=path_log,
+            filemode="a",
+            level=logging.DEBUG,
+        )
+        settings = import_ifc.IfcImportSettings.factory(context, self.filepath, logger)
+        settings.has_filter = True
+        settings.should_filter_spatial_elements = False
+        settings.elements = delta_elements
+        settings.logger.info("Starting import")
+        ifc_importer = import_ifc.IfcImporter(settings)
+        ifc_importer.execute()
+        settings.logger.info("Import finished in {:.2f} seconds".format(time.time() - start))
+        print("Import finished in {:.2f} seconds".format(time.time() - start))
+
+        context.scene.BIMProperties.ifc_file = self.filepath
         return {"FINISHED"}
 
+    def invoke(self, context, event):
+        context.window_manager.fileselect_add(self)
+        return {"RUNNING_MODAL"}
+
 
 class AddIfcFile(bpy.types.Operator):
     bl_idname = "bim.add_ifc_file"