From f13a9d0e969a39fa77137fa38e9dba4bd3dd1a2e Mon Sep 17 00:00:00 2001
From: Tulir Asokan <tulir@maunium.net>
Date: Sun, 14 Aug 2022 01:49:39 +0300
Subject: [PATCH] Add support for disappearing messages

---
 CHANGELOG.md                                  |  1 +
 mautrix_telegram/portal.py                    | 27 ++++++++++++++++++-
 .../portal_util/message_convert.py            | 10 ++++---
 3 files changed, 34 insertions(+), 4 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9948c090..1f4048b0 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,7 @@ Minimum Conduit version remains at 0.4.0.
 * Added option to include captions in the same message as the media to
   implement [MSC2530]. Sending captions the same way is also supported and
   enabled by default.
+* Added support for Telegram's disappearing messages.
 * Added support for bridging forwarded messages as forwards on Telegram.
   * Forwarding is not allowed in relay mode as the bot wouldn't be able to
     specify who sent the message.
diff --git a/mautrix_telegram/portal.py b/mautrix_telegram/portal.py
index e922ff42..5216a1e3 100644
--- a/mautrix_telegram/portal.py
+++ b/mautrix_telegram/portal.py
@@ -1843,6 +1843,12 @@ class Portal(DBPortal, BasePortal):
         )
         await self._send_delivery_receipt(event_id)
         asyncio.create_task(self._send_message_status(event_id, err=None))
+        if response.ttl_period:
+            await self._mark_disappearing(
+                event_id=event_id,
+                seconds=response.ttl_period,
+                expires_at=int(response.date.timestamp()) + response.ttl_period,
+            )
 
     async def _send_message_status(self, event_id: EventID, err: Exception | None) -> None:
         if not self.config["bridge.message_status_events"]:
@@ -2867,8 +2873,9 @@ class Portal(DBPortal, BasePortal):
         event_id = await self._send_message(
             intent, converted.content, timestamp=evt.date, event_type=converted.type
         )
+        caption_id = None
         if converted.caption:
-            await self._send_message(intent, converted.caption, timestamp=evt.date)
+            caption_id = await self._send_message(intent, converted.caption, timestamp=evt.date)
 
         self._new_messages_after_sponsored = True
 
@@ -2914,6 +2921,24 @@ class Portal(DBPortal, BasePortal):
                 )
             )
         await self._send_delivery_receipt(event_id)
+        if converted.disappear_seconds:
+            if converted.disappear_start_immediately:
+                expires_at = int(evt.date.timestamp()) + converted.disappear_seconds
+            else:
+                expires_at = None
+            await self._mark_disappearing(event_id, converted.disappear_seconds, expires_at)
+            if caption_id:
+                await self._mark_disappearing(caption_id, converted.disappear_seconds, expires_at)
+
+    async def _mark_disappearing(
+        self, event_id: EventID, seconds: int, expires_at: int | None
+    ) -> None:
+        dm = DisappearingMessage(
+            self.mxid, event_id, seconds * 1000, expiration_ts=expires_at * 1000
+        )
+        await dm.insert()
+        if expires_at:
+            asyncio.create_task(self._disappear_event(dm))
 
     async def _create_room_on_action(
         self, source: au.AbstractUser, action: TypeMessageAction
diff --git a/mautrix_telegram/portal_util/message_convert.py b/mautrix_telegram/portal_util/message_convert.py
index 072c0c1b..84f3f707 100644
--- a/mautrix_telegram/portal_util/message_convert.py
+++ b/mautrix_telegram/portal_util/message_convert.py
@@ -92,7 +92,8 @@ class ConvertedMessage:
     content: MessageEventContent
     caption: MessageEventContent | None = None
     type: EventType = EventType.ROOM_MESSAGE
-    disappear_in: int | None = None
+    disappear_seconds: int | None = None
+    disappear_start_immediately: bool = False
 
 
 class DocAttrs(NamedTuple):
@@ -158,6 +159,9 @@ class TelegramMessageConverter:
             self.log.debug("Unhandled Telegram message %d", evt.id)
             return
         if converted:
+            if evt.ttl_period and not converted.disappear_seconds:
+                converted.disappear_seconds = evt.ttl_period
+                converted.disappear_start_immediately = True
             converted.content.external_url = self._get_external_url(evt)
             converted.content["fi.mau.telegram.source"] = {
                 "space": self.portal.tgid if self.portal.peer_type == "channel" else source.tgid,
@@ -388,7 +392,7 @@ class TelegramMessageConverter:
         return ConvertedMessage(
             content=content,
             caption=caption_content,
-            disappear_in=media.ttl_seconds,
+            disappear_seconds=media.ttl_seconds,
         )
 
     async def _convert_document(
@@ -488,7 +492,7 @@ class TelegramMessageConverter:
             type=event_type,
             content=content,
             caption=caption_content,
-            disappear_in=evt.media.ttl_seconds,
+            disappear_seconds=evt.media.ttl_seconds,
         )
 
     @staticmethod