Room version based on room ID

vona/globals/__init__.py

@@ -1,3 +1,4 @@
+from collections import Counter
 import vona.config as config
 import nacl.signing
 import hashlib
@@ -7,7 +8,7 @@ import copy
 import json
 import re
 
-version = "25w41b"
+version = "1.4.2"
 
 
 def canonical_json(value):
@@ -223,3 +224,29 @@ def hash_and_sign_event(event_object):
 	signed_object = sign_json(stripped_object)
 	event_object["signatures"] = signed_object["signatures"]
 	return event_object
+
+
+def room_version_from_id(room_id):
+	room_id_no_sigil = room_id.replace("!", "")
+
+	hexadecimal_room_id = bytes(room_id_no_sigil, "utf-8").hex()
+
+	if "1" not in hexadecimal_room_id and "2" not in hexadecimal_room_id:
+		# NOTE: v2 if impossible from room ID alone
+		hexadecimal_room_id = "2" + hexadecimal_room_id[1:]
+
+	def remove_chars(s):
+		return re.sub("[^12]", "", s)
+
+	nums = remove_chars(hexadecimal_room_id)
+
+	def most_common_character(s):
+		s = s.replace(" ", "").lower()
+
+		counts = Counter(s)
+
+		most_common = counts.most_common(1)
+
+		return most_common[0] if most_common else None
+
+	return most_common_character(nums)[0]