Fix old power events sent when setting user level

TODO.md

@@ -1,6 +1,5 @@
 # TODO
 
-- don't trust PowerLevelsEvent, may be old
 - fix button layout
 - improve power levels event text
 

src/backend/matrix_client.py

@@ -191,8 +191,8 @@ class MatrixClient(nio.AsyncClient):
         self.loaded_once_rooms:    Set[str]       = set()  # {room_id}
         self.cleared_events_rooms: Set[str]       = set()  # {room_id}
 
-        # {room_id: <m.room.power_levels event content dict>}
+        # {room_id: event}
-        self.power_levels_content: Dict[str, Dict[str, Any]] = {}
+        self.power_level_events: Dict[str, nio.PowerLevelsEvent] = {}
 
         self.nio_callbacks = NioCallbacks(self)
 
@@ -1128,10 +1128,10 @@ class MatrixClient(nio.AsyncClient):
     ) -> None:
         """Set a room member's power level."""
 
-        while room_id not in self.power_levels_content:
+        while room_id not in self.power_level_events:
             await asyncio.sleep(0.2)
 
-        content = deepcopy(self.power_levels_content[room_id])
+        content = deepcopy(self.power_level_events[room_id].source["content"])
         content.setdefault("users", {})[user_id] = level
 
         await self.room_put_state(room_id, "m.room.power_levels", content)

src/backend/nio_callbacks.py

@@ -83,6 +83,14 @@ class NioCallbacks:
             if room_id not in self.client.past_tokens:
                 self.client.past_tokens[room_id] = info.timeline.prev_batch
 
+            for ev in info.state:
+                if isinstance(ev, nio.PowerLevelsEvent):
+                    stored = self.client.power_level_events.get(room_id)
+                    time   = ev.server_timestamp
+
+                    if not stored or time > stored.server_timestamp:
+                        self.client.power_level_events[room_id] = ev
+
         # TODO: way of knowing if a nio.MatrixRoom is left
         for room_id, info in resp.rooms.leave.items():
             # TODO: handle in nio, these are rooms that were left before
@@ -313,7 +321,10 @@ class NioCallbacks:
     async def onPowerLevelsEvent(
         self, room: nio.MatrixRoom, ev: nio.PowerLevelsEvent,
     ) -> None:
-        self.client.power_levels_content[room.room_id] = ev.source["content"]
+        stored = self.client.power_level_events.get(room.room_id)
+
+        if not stored or ev.server_timestamp > stored.server_timestamp:
+            self.client.power_level_events[room.room_id] = ev
 
         try:
             previous_levels = ev.source["unsigned"]["prev_content"]["users"]