Adapt extremities endpoint for v3+

vona/federation/__init__.py

@@ -20,6 +20,7 @@ class bullshit:
 	def get_json():
 		return {}
 
+
 def send_join(request, room) -> dict:
 	if globals.room_version_from_id(room) in ["1", "2"]:
 		return rooms.v1_v2(request, room)
@@ -335,10 +336,25 @@ async def backfill(room):
 @server.route("/_matrix/federation/unstable/org.matrix.msc4370/extremities/<room>")
 @server.route("/_matrix/federation/v1/extremities/<room>")
 async def extremities(room):
+	if ":" in room:
+		if room.split(":")[1] != config.server_name:
+			return jsonify({
+				"errcode": "M_NOT_FOUND",
+				"error": f"Room is unknown to this server"
+			}), 404
+
+	room_ver = globals.room_version_from_id(room)
+
+	if room_ver in ["1", "2"]:
+		event_id = globals.make_event_id(seed=f"6_{room}")
+	else:
+		event_id = globals.make_ref_hash(
+			send_join(bullshit, room)["state"][5],
+			int(room_ver)
+		)
+
 	return jsonify({
-		"prev_events": [
-			globals.make_event_id(seed=f"6_{room}"),
-		]
+		"prev_events": [event_id]
 	})