Fix rate limit issue on raw reaction add/remove events. (modmail-dev#3306)

* Fix rate limit issue on raw reaction add/remove events.

* Pasd message object to `find_linked_messages` since it is already fetched.

---------

Co-authored-by: Taku <45324516+Taaku18@users.noreply.github.com>

Author: Jerrie-Aries

bot.py

@@ -1222,33 +1222,44 @@ async def handle_reaction_events(self, payload):
             return
 
         channel = self.get_channel(payload.channel_id)
-        if not channel:  # dm channel not in internal cache
-            _thread = await self.threads.find(recipient=user)
-            if not _thread:
+        thread = None
+        # dm channel not in internal cache
+        if not channel:
+            thread = await self.threads.find(recipient=user)
+            if not thread:
+                return
+            channel = await thread.recipient.create_dm()
+            if channel.id != payload.channel_id:
+                return
+
+        from_dm = isinstance(channel, discord.DMChannel)
+        from_txt = isinstance(channel, discord.TextChannel)
+        if not from_dm and not from_txt:
+            return
+
+        if not thread:
+            params = {"recipient": user} if from_dm else {"channel": channel}
+            thread = await self.threads.find(**params)
+            if not thread:
                 return
-            channel = await _thread.recipient.create_dm()
 
+        # thread must exist before doing this API call
         try:
             message = await channel.fetch_message(payload.message_id)
         except (discord.NotFound, discord.Forbidden):
             return
 
         reaction = payload.emoji
-
         close_emoji = await self.convert_emoji(self.config["close_emoji"])
-
-        if isinstance(channel, discord.DMChannel):
-            thread = await self.threads.find(recipient=user)
-            if not thread:
-                return
+        if from_dm:
             if (
                 payload.event_type == "REACTION_ADD"
                 and message.embeds
                 and str(reaction) == str(close_emoji)
                 and self.config.get("recipient_thread_close")
             ):
                 ts = message.embeds[0].timestamp
-                if thread and ts == thread.channel.created_at:
+                if ts == thread.channel.created_at:
                     # the reacted message is the corresponding thread creation embed
                     # closing thread
                     return await thread.close(closer=user)
@@ -1268,11 +1279,10 @@ async def handle_reaction_events(self, payload):
                 logger.warning("Failed to find linked message for reactions: %s", e)
                 return
         else:
-            thread = await self.threads.find(channel=channel)
-            if not thread:
-                return
             try:
-                _, *linked_messages = await thread.find_linked_messages(message.id, either_direction=True)
+                _, *linked_messages = await thread.find_linked_messages(
+                    message1=message, either_direction=True
+                )
             except ValueError as e:
                 logger.warning("Failed to find linked message for reactions: %s", e)
                 return