server: add an endpoint to merge speaker

server/reflector/views/transcripts_speaker.py

@@ -23,6 +23,11 @@ class SpeakerAssignmentStatus(BaseModel):
     status: str
 
 
+class SpeakerMerge(BaseModel):
+    speaker_from: int
+    speaker_to: int
+
+
 @router.patch("/transcripts/{transcript_id}/speaker/assign")
 async def transcript_assign_speaker(
     transcript_id: str,
@@ -61,3 +66,66 @@ async def transcript_assign_speaker(
     )
 
     return SpeakerAssignmentStatus(status="ok")
+
+
+@router.patch("/transcripts/{transcript_id}/speaker/merge")
+async def transcript_merge_speaker(
+    transcript_id: str,
+    merge: SpeakerMerge,
+    user: Annotated[Optional[auth.UserInfo], Depends(auth.current_user_optional)],
+) -> SpeakerAssignmentStatus:
+    user_id = user["sub"] if user else None
+    transcript = await transcripts_controller.get_by_id_for_http(
+        transcript_id, user_id=user_id
+    )
+
+    if not transcript:
+        raise HTTPException(status_code=404, detail="Transcript not found")
+
+    # ensure both speaker are not assigned to the 2 differents participants
+    participant_from = next(
+        (
+            participant
+            for participant in transcript.participants
+            if participant.speaker == merge.speaker_from
+        ),
+        None,
+    )
+    participant_to = next(
+        (
+            participant
+            for participant in transcript.participants
+            if participant.speaker == merge.speaker_to
+        ),
+        None,
+    )
+    if participant_from and participant_to:
+        raise HTTPException(
+            status_code=400,
+            detail="Both speakers are assigned to participants",
+        )
+
+    # reassign speakers from words in the transcript
+    speaker_from = merge.speaker_from
+    speaker_to = merge.speaker_to
+    changed_topics = []
+    for topic in transcript.topics:
+        changed = False
+        for word in topic.words:
+            if word.speaker == speaker_from:
+                word.speaker = speaker_to
+                changed = True
+        if changed:
+            changed_topics.append(topic)
+
+    # batch changes
+    for topic in changed_topics:
+        transcript.upsert_topic(topic)
+    await transcripts_controller.update(
+        transcript,
+        {
+            "topics": transcript.topics_dump(),
+        },
+    )
+
+    return SpeakerAssignmentStatus(status="ok")