Ensure data path works on most FS

Also following the same changes in python-omemo.
Signed-off-by: Maxime “pep” Buquet <pep@bouah.net>

poezio_plugins/omemo/__init__.py

@@ -12,6 +12,8 @@
 
 import os
 import asyncio
+import base64
+import hashlib
 import logging
 from typing import Dict, List, Optional
 
@@ -60,7 +62,10 @@ class Plugin(E2EEPlugin):
 
         self.info = lambda i: self.api.information(i, 'Info')
 
-        data_dir = os.path.join(DATA_HOME, 'omemo', self.core.xmpp.boundjid.bare)
+        jid_str = self.core.xmpp.boundjid.bare.encode('US-ASCII')
+        digest = hashlib.sha256(jid_str).digest()
+        hashed_jid = base64.b32encode(digest).decode('US-ASCII')
+        data_dir = os.path.join(DATA_HOME, 'omemo', hashed_jid)
         os.makedirs(data_dir, exist_ok=True)
 
         try: