bonsai bcf v3 - support adding/removing related topics #2790

Not entirely sure about TopicHandler.guid typing, just made it consistent with v2 for now.

src/bcf/bcf/v3/topic.py

@@ -49,11 +49,11 @@ class TopicHandler:
         return self.markup.topic
 
     @property
-    def guid(self) -> Optional[str]:
+    def guid(self) -> str:
         """Return the GUID of the topic."""
         if self._markup:
             return self.topic.guid
-        return self._topic_dir.name if self._topic_dir else None
+        return self._topic_dir.name if self._topic_dir else ""
 
     @property
     def header(self) -> Optional[mdl.Header]:

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

@@ -441,21 +441,25 @@ class AddBcfRelatedTopic(bpy.types.Operator):
     def execute(self, context):
         bcfxml = bcfstore.BcfStore.get_bcfxml()
         assert bcfxml
-
-        if not (version := (bcfxml.version.version_id or "")).startswith("2"):
-            self.report({"INFO"}, f"BCF {version} is not yet supported: {self.bl_rna.bl_idname}.")
-            return {"FINISHED"}
+        bcf_v2 = (bcfxml.version.version_id or "").startswith("2")
 
         props = context.scene.BCFProperties
         blender_topic = props.active_topic
         topic = bcfxml.topics[blender_topic.name]
-        topic.topic.related_topic.append(
-            bcf.v2.model.TopicRelatedTopic(
-                guid=next((t for t in bcfxml.topics.values() if t.topic.title == props.related_topic)).guid
-            )
-        )
+        related_topics = tool.Bcf.get_topic_related_topics(topic)
+        related_topic_guid = props.related_topic
+
+        if bcf_v2:
+            assert tool.Bcf.is_list_of(related_topics, bcf.v2.model.TopicRelatedTopic)
+            related_topic = bcf.v2.model.TopicRelatedTopic(guid=related_topic_guid)
+            related_topics.append(related_topic)
+        else:
+            assert tool.Bcf.is_list_of(related_topics, bcf.v3.model.TopicRelatedTopicsRelatedTopic)
+            related_topic = bcf.v3.model.TopicRelatedTopicsRelatedTopic(guid=related_topic_guid)
+            related_topics.append(related_topic)
+
+        tool.Bcf.set_topic_related_topics(topic, related_topics)
         bpy.ops.bim.load_bcf_topic(topic_guid=topic.guid, topic_index=props.active_topic_index)
-        props.related_topic = ""
         return {"FINISHED"}
 
 
@@ -982,14 +986,12 @@ class RemoveBcfRelatedTopic(bpy.types.Operator):
         bcfxml = bcfstore.BcfStore.get_bcfxml()
         assert bcfxml
 
-        if not (version := (bcfxml.version.version_id or "")).startswith("2"):
-            self.report({"INFO"}, f"BCF {version} is not yet supported: {self.bl_rna.bl_idname}.")
-            return {"FINISHED"}
-
         props = context.scene.BCFProperties
         blender_topic = props.active_topic
         topic = bcfxml.topics[blender_topic.name]
-        del topic.topic.related_topic[self.index]
+        related_topics = tool.Bcf.get_topic_related_topics(topic)
+        del related_topics[self.index]
+        tool.Bcf.set_topic_related_topics(topic, related_topics)
         bpy.ops.bim.load_bcf_topic(topic_guid=topic.guid, topic_index=props.active_topic_index)
         return {"FINISHED"}
 

src/bonsai/bonsai/tool/bcf.py

@@ -169,6 +169,25 @@ class Bcf(bonsai.core.tool.Bcf):
             related_topics = related_topics.related_topic if related_topics else []
         return related_topics
 
+    @classmethod
+    def set_topic_related_topics(
+        cls,
+        topic: bcf.agnostic.topic.TopicHandler,
+        related_topics: Union[list[bcf.v2.model.TopicRelatedTopic], list[bcf.v3.model.TopicRelatedTopicsRelatedTopic]],
+    ) -> None:
+        topic_ = topic.topic
+        if isinstance(topic_, bcf.v2.model.Topic):
+            assert cls.is_list_of(related_topics, bcf.v2.model.TopicRelatedTopic)
+            topic_.related_topic = related_topics
+        else:
+            assert cls.is_list_of(related_topics, bcf.v3.model.TopicRelatedTopicsRelatedTopic)
+            topic_related_topics = topic_.related_topics
+            if topic_related_topics is None:
+                if not related_topics:
+                    return
+                topic_.related_topics = (topic_related_topics := bcf.v3.model.TopicRelatedTopics())
+            topic_related_topics.related_topic = related_topics
+
     ## visinfo
     @classmethod
     def get_viewpoint_bitmaps(