feat(telegram): add configurable group mention policy

nanobot/channels/telegram.py

@@ -179,6 +179,8 @@ class TelegramChannel(BaseChannel):
         self._media_group_buffers: dict[str, dict] = {}
         self._media_group_tasks: dict[str, asyncio.Task] = {}
         self._message_threads: dict[tuple[str, int], int] = {}
+        self._bot_user_id: int | None = None
+        self._bot_username: str | None = None
 
     def is_allowed(self, sender_id: str) -> bool:
         """Preserve Telegram's legacy id|username allowlist matching."""
@@ -242,6 +244,8 @@ class TelegramChannel(BaseChannel):
 
         # Get bot info and register command menu
         bot_info = await self._app.bot.get_me()
+        self._bot_user_id = getattr(bot_info, "id", None)
+        self._bot_username = getattr(bot_info, "username", None)
         logger.info("Telegram bot @{} connected", bot_info.username)
 
         try:
@@ -462,6 +466,70 @@ class TelegramChannel(BaseChannel):
             "is_forum": bool(getattr(message.chat, "is_forum", False)),
         }
 
+    async def _ensure_bot_identity(self) -> tuple[int | None, str | None]:
+        """Load bot identity once and reuse it for mention/reply checks."""
+        if self._bot_user_id is not None or self._bot_username is not None:
+            return self._bot_user_id, self._bot_username
+        if not self._app:
+            return None, None
+        bot_info = await self._app.bot.get_me()
+        self._bot_user_id = getattr(bot_info, "id", None)
+        self._bot_username = getattr(bot_info, "username", None)
+        return self._bot_user_id, self._bot_username
+
+    @staticmethod
+    def _has_mention_entity(
+        text: str,
+        entities,
+        bot_username: str,
+        bot_id: int | None,
+    ) -> bool:
+        """Check Telegram mention entities against the bot username."""
+        handle = f"@{bot_username}".lower()
+        for entity in entities or []:
+            entity_type = getattr(entity, "type", None)
+            if entity_type == "text_mention":
+                user = getattr(entity, "user", None)
+                if user is not None and bot_id is not None and getattr(user, "id", None) == bot_id:
+                    return True
+                continue
+            if entity_type != "mention":
+                continue
+            offset = getattr(entity, "offset", None)
+            length = getattr(entity, "length", None)
+            if offset is None or length is None:
+                continue
+            if text[offset : offset + length].lower() == handle:
+                return True
+        return handle in text.lower()
+
+    async def _is_group_message_for_bot(self, message) -> bool:
+        """Allow group messages when policy is open, @mentioned, or replying to the bot."""
+        if message.chat.type == "private" or self.config.group_policy == "open":
+            return True
+
+        bot_id, bot_username = await self._ensure_bot_identity()
+        if bot_username:
+            text = message.text or ""
+            caption = message.caption or ""
+            if self._has_mention_entity(
+                text,
+                getattr(message, "entities", None),
+                bot_username,
+                bot_id,
+            ):
+                return True
+            if self._has_mention_entity(
+                caption,
+                getattr(message, "caption_entities", None),
+                bot_username,
+                bot_id,
+            ):
+                return True
+
+        reply_user = getattr(getattr(message, "reply_to_message", None), "from_user", None)
+        return bool(bot_id and reply_user and reply_user.id == bot_id)
+
     def _remember_thread_context(self, message) -> None:
         """Cache topic thread id by chat/message id for follow-up replies."""
         message_thread_id = getattr(message, "message_thread_id", None)
@@ -501,21 +569,7 @@ class TelegramChannel(BaseChannel):
         # Store chat_id for replies
         self._chat_ids[sender_id] = chat_id
 
-        # Enforce group_policy: in group chats with "mention" policy,
+        if not await self._is_group_message_for_bot(message):
-        # only respond when the bot is @mentioned or the message is a reply to the bot.
-        is_group = message.chat.type != "private"
-        if is_group and getattr(self.config, "group_policy", "open") == "mention":
-            bot_username = (await self._app.bot.get_me()).username if self._app else None
-            mentioned = False
-            # Check if bot is @mentioned in text
-            if bot_username and message.text:
-                mentioned = f"@{bot_username}" in message.text
-            # Check if the message is a reply to the bot
-            if not mentioned and message.reply_to_message and message.reply_to_message.from_user:
-                bot_id = (await self._app.bot.get_me()).id if self._app else None
-                if bot_id and message.reply_to_message.from_user.id == bot_id:
-                    mentioned = True
-            if not mentioned:
             return
 
         # Build content from text and/or media

nanobot/config/schema.py

@@ -33,7 +33,7 @@ class TelegramConfig(Base):
         None  # HTTP/SOCKS5 proxy URL, e.g. "http://127.0.0.1:7890" or "socks5://127.0.0.1:1080"
     )
     reply_to_message: bool = False  # If true, bot replies quote the original message
-    group_policy: Literal["open", "mention"] = "open"  # "open" responds to all, "mention" only when @mentioned or replied to
+    group_policy: Literal["open", "mention"] = "mention"  # "mention" responds when @mentioned or replied to, "open" responds to all
 
 
 class FeishuConfig(Base):

tests/test_telegram_channel.py

@@ -27,9 +27,11 @@ class _FakeUpdater:
 class _FakeBot:
     def __init__(self) -> None:
         self.sent_messages: list[dict] = []
+        self.get_me_calls = 0
 
     async def get_me(self):
-        return SimpleNamespace(username="nanobot_test")
+        self.get_me_calls += 1
+        return SimpleNamespace(id=999, username="nanobot_test")
 
     async def set_my_commands(self, commands) -> None:
         self.commands = commands
@@ -37,6 +39,9 @@ class _FakeBot:
     async def send_message(self, **kwargs) -> None:
         self.sent_messages.append(kwargs)
 
+    async def send_chat_action(self, **kwargs) -> None:
+        pass
+
 
 class _FakeApp:
     def __init__(self, on_start_polling) -> None:
@@ -87,6 +92,35 @@ class _FakeBuilder:
         return self.app
 
 
+def _make_telegram_update(
+    *,
+    chat_type: str = "group",
+    text: str | None = None,
+    caption: str | None = None,
+    entities=None,
+    caption_entities=None,
+    reply_to_message=None,
+):
+    user = SimpleNamespace(id=12345, username="alice", first_name="Alice")
+    message = SimpleNamespace(
+        chat=SimpleNamespace(type=chat_type, is_forum=False),
+        chat_id=-100123,
+        text=text,
+        caption=caption,
+        entities=entities or [],
+        caption_entities=caption_entities or [],
+        reply_to_message=reply_to_message,
+        photo=None,
+        voice=None,
+        audio=None,
+        document=None,
+        media_group_id=None,
+        message_thread_id=None,
+        message_id=1,
+    )
+    return SimpleNamespace(message=message, effective_user=user)
+
+
 @pytest.mark.asyncio
 async def test_start_uses_request_proxy_without_builder_proxy(monkeypatch) -> None:
     config = TelegramConfig(
@@ -131,6 +165,10 @@ def test_get_extension_falls_back_to_original_filename() -> None:
     assert channel._get_extension("file", None, "archive.tar.gz") == ".tar.gz"
 
 
+def test_telegram_group_policy_defaults_to_mention() -> None:
+    assert TelegramConfig().group_policy == "mention"
+
+
 def test_is_allowed_accepts_legacy_telegram_id_username_formats() -> None:
     channel = TelegramChannel(TelegramConfig(allow_from=["12345", "alice", "67890|bob"]), MessageBus())
 
@@ -182,3 +220,119 @@ async def test_send_reply_infers_topic_from_message_id_cache() -> None:
 
     assert channel._app.bot.sent_messages[0]["message_thread_id"] == 42
     assert channel._app.bot.sent_messages[0]["reply_parameters"].message_id == 10
+
+
+@pytest.mark.asyncio
+async def test_group_policy_mention_ignores_unmentioned_group_message() -> None:
+    channel = TelegramChannel(
+        TelegramConfig(enabled=True, token="123:abc", allow_from=["*"], group_policy="mention"),
+        MessageBus(),
+    )
+    channel._app = _FakeApp(lambda: None)
+
+    handled = []
+
+    async def capture_handle(**kwargs) -> None:
+        handled.append(kwargs)
+
+    channel._handle_message = capture_handle
+    channel._start_typing = lambda _chat_id: None
+
+    await channel._on_message(_make_telegram_update(text="hello everyone"), None)
+
+    assert handled == []
+    assert channel._app.bot.get_me_calls == 1
+
+
+@pytest.mark.asyncio
+async def test_group_policy_mention_accepts_text_mention_and_caches_bot_identity() -> None:
+    channel = TelegramChannel(
+        TelegramConfig(enabled=True, token="123:abc", allow_from=["*"], group_policy="mention"),
+        MessageBus(),
+    )
+    channel._app = _FakeApp(lambda: None)
+
+    handled = []
+
+    async def capture_handle(**kwargs) -> None:
+        handled.append(kwargs)
+
+    channel._handle_message = capture_handle
+    channel._start_typing = lambda _chat_id: None
+
+    mention = SimpleNamespace(type="mention", offset=0, length=13)
+    await channel._on_message(_make_telegram_update(text="@nanobot_test hi", entities=[mention]), None)
+    await channel._on_message(_make_telegram_update(text="@nanobot_test again", entities=[mention]), None)
+
+    assert len(handled) == 2
+    assert channel._app.bot.get_me_calls == 1
+
+
+@pytest.mark.asyncio
+async def test_group_policy_mention_accepts_caption_mention() -> None:
+    channel = TelegramChannel(
+        TelegramConfig(enabled=True, token="123:abc", allow_from=["*"], group_policy="mention"),
+        MessageBus(),
+    )
+    channel._app = _FakeApp(lambda: None)
+
+    handled = []
+
+    async def capture_handle(**kwargs) -> None:
+        handled.append(kwargs)
+
+    channel._handle_message = capture_handle
+    channel._start_typing = lambda _chat_id: None
+
+    mention = SimpleNamespace(type="mention", offset=0, length=13)
+    await channel._on_message(
+        _make_telegram_update(caption="@nanobot_test photo", caption_entities=[mention]),
+        None,
+    )
+
+    assert len(handled) == 1
+    assert handled[0]["content"] == "@nanobot_test photo"
+
+
+@pytest.mark.asyncio
+async def test_group_policy_mention_accepts_reply_to_bot() -> None:
+    channel = TelegramChannel(
+        TelegramConfig(enabled=True, token="123:abc", allow_from=["*"], group_policy="mention"),
+        MessageBus(),
+    )
+    channel._app = _FakeApp(lambda: None)
+
+    handled = []
+
+    async def capture_handle(**kwargs) -> None:
+        handled.append(kwargs)
+
+    channel._handle_message = capture_handle
+    channel._start_typing = lambda _chat_id: None
+
+    reply = SimpleNamespace(from_user=SimpleNamespace(id=999))
+    await channel._on_message(_make_telegram_update(text="reply", reply_to_message=reply), None)
+
+    assert len(handled) == 1
+
+
+@pytest.mark.asyncio
+async def test_group_policy_open_accepts_plain_group_message() -> None:
+    channel = TelegramChannel(
+        TelegramConfig(enabled=True, token="123:abc", allow_from=["*"], group_policy="open"),
+        MessageBus(),
+    )
+    channel._app = _FakeApp(lambda: None)
+
+    handled = []
+
+    async def capture_handle(**kwargs) -> None:
+        handled.append(kwargs)
+
+    channel._handle_message = capture_handle
+    channel._start_typing = lambda _chat_id: None
+
+    await channel._on_message(_make_telegram_update(text="hello group"), None)
+
+    assert len(handled) == 1
+    assert channel._app.bot.get_me_calls == 0