Handle m.room.avatar, improve name/topic/alias

- Display the new room's avatar as an EventImage
- Show "x removed the room's avatar" if it's set to none
- Show "x removed the room's y" for empty name/topic/canonical alias
  events instead of "x changed the y to ''"

src/python/models/items.py

@@ -193,19 +193,15 @@ class Event(ModelItem):
 
     @property
     def links(self) -> List[str]:
-        local_type    = self.local_event_type
-        media_classes = (nio.RoomMessageMedia, nio.RoomEncryptedMedia)
+        urls: List[str] = []
 
-        if local_type and issubclass(local_type, media_classes):
-            return [self.media_url]
+        if self.content.strip():
+            urls += [link[2] for link in lxml.html.iterlinks(self.content)]
 
-        if isinstance(self.source, media_classes):
-            return [self.media_url]
+        if self.media_url:
+            urls.append(self.media_url)
 
-        if not self.content.strip():
-            return []
-
-        return [link[2] for link in lxml.html.iterlinks(self.content)]
+        return urls
 
 
 @dataclass

src/python/nio_callbacks.py

@@ -281,18 +281,41 @@ class NioCallbacks:
 
 
     async def onRoomAliasEvent(self, room, ev) -> None:
-        co = f"%1 set the room's main address to {ev.canonical_alias}."
+        if ev.canonical_alias:
+            co = f"%1 set the room's main address to {ev.canonical_alias}."
+        else:
+            co = "%1 removed the room's main address."
+
         await self.client.register_nio_event(room, ev, content=co)
 
 
     async def onRoomNameEvent(self, room, ev) -> None:
-        co = f"%1 changed the room's name to \"{ev.name}\"."
+        if ev.name:
+            co = f"%1 changed the room's name to \"{ev.name}\"."
+        else:
+            co = "%1 removed the room's name."
+
         await self.client.register_nio_event(room, ev, content=co)
 
 
+    async def onRoomAvatarEvent(self, room, ev) -> None:
+        if ev.avatar_url:
+            co = "%1 changed the room's picture:"
+        else:
+            co = "%1 removed the room's picture."
+
+        await self.client.register_nio_event(
+            room, ev, content=co, media_url=ev.avatar_url,
+        )
+
+
     async def onRoomTopicEvent(self, room, ev) -> None:
-        topic = HTML_FILTER.filter_inline(ev.topic)
-        co    = f"%1 changed the room's topic to \"{topic}\"."
+        if ev.topic:
+            topic = HTML_FILTER.filter_inline(ev.topic)
+            co    = f"%1 changed the room's topic to \"{topic}\"."
+        else:
+            co = "%1 removed the room's topic."
+
         await self.client.register_nio_event(room, ev, content=co)
 
 

src/qml/Chat/Timeline/EventMediaLoader.qml

@@ -29,6 +29,9 @@ HLoader {
     ]
 
     readonly property int type: {
+        if (singleMediaInfo.event_type == "RoomAvatarEvent")
+            return EventDelegate.Media.Image
+
         let mainType = singleMediaInfo.media_mime.split("/")[0].toLowerCase()
 
         if (mainType === "image") return EventDelegate.Media.Image