"""
Telegram platform adapter.

Uses python-telegram-bot library for:
- Receiving messages from users/groups
- Sending responses back
- Handling media and commands
"""

import asyncio
import json
import logging
import os
import re
from typing import Dict, List, Optional, Any

logger = logging.getLogger(__name__)

try:
    from telegram import Update, Bot, Message, InlineKeyboardButton, InlineKeyboardMarkup
    from telegram.ext import (
        Application,
        CommandHandler,
        CallbackQueryHandler,
        MessageHandler as TelegramMessageHandler,
        ContextTypes,
        filters,
    )
    from telegram.constants import ParseMode, ChatType
    from telegram.request import HTTPXRequest
    TELEGRAM_AVAILABLE = True
except ImportError:
    TELEGRAM_AVAILABLE = False
    Update = Any
    Bot = Any
    Message = Any
    InlineKeyboardButton = Any
    InlineKeyboardMarkup = Any
    Application = Any
    CommandHandler = Any
    CallbackQueryHandler = Any
    TelegramMessageHandler = Any
    HTTPXRequest = Any
    filters = None
    ParseMode = None
    ChatType = None

    # Mock ContextTypes so type annotations using ContextTypes.DEFAULT_TYPE
    # don't crash during class definition when the library isn't installed.
    class _MockContextTypes:
        DEFAULT_TYPE = Any
    ContextTypes = _MockContextTypes

import sys
from pathlib import Path as _Path
sys.path.insert(0, str(_Path(__file__).resolve().parents[2]))

from gateway.config import Platform, PlatformConfig
from gateway.platforms.base import (
    BasePlatformAdapter,
    MessageEvent,
    MessageType,
    ProcessingOutcome,
    SendResult,
    cache_image_from_bytes,
    cache_audio_from_bytes,
    cache_document_from_bytes,
    resolve_proxy_url,
    SUPPORTED_DOCUMENT_TYPES,
    utf16_len,
    _prefix_within_utf16_limit,
)
from gateway.platforms.telegram_network import (
    TelegramFallbackTransport,
    discover_fallback_ips,
    parse_fallback_ip_env,
)


def check_telegram_requirements() -> bool:
    """Check if Telegram dependencies are available."""
    return TELEGRAM_AVAILABLE


# Matches every character that MarkdownV2 requires to be backslash-escaped
# when it appears outside a code span or fenced code block.
_MDV2_ESCAPE_RE = re.compile(r'([_*\[\]()~`>#\+\-=|{}.!\\])')


def _escape_mdv2(text: str) -> str:
    """Escape Telegram MarkdownV2 special characters with a preceding backslash."""
    return _MDV2_ESCAPE_RE.sub(r'\\\1', text)


def _strip_mdv2(text: str) -> str:
    """Strip MarkdownV2 escape backslashes to produce clean plain text.

    Also removes MarkdownV2 formatting markers so the fallback
    doesn't show stray syntax characters from format_message conversion.
    """
    # Remove escape backslashes before special characters
    cleaned = re.sub(r'\\([_*\[\]()~`>#\+\-=|{}.!\\])', r'\1', text)
    # Remove MarkdownV2 bold markers that format_message converted from **bold**
    cleaned = re.sub(r'\*([^*]+)\*', r'\1', cleaned)
    # Remove MarkdownV2 italic markers that format_message converted from *italic*
    # Use word boundary (\b) to avoid breaking snake_case like my_variable_name
    cleaned = re.sub(r'(?<!\w)_([^_]+)_(?!\w)', r'\1', cleaned)
    # Remove MarkdownV2 strikethrough markers (~text~ → text)
    cleaned = re.sub(r'~([^~]+)~', r'\1', cleaned)
    # Remove MarkdownV2 spoiler markers (||text|| → text)
    cleaned = re.sub(r'\|\|([^|]+)\|\|', r'\1', cleaned)
    return cleaned


class TelegramAdapter(BasePlatformAdapter):
    """
    Telegram bot adapter.
    
    Handles:
    - Receiving messages from users and groups
    - Sending responses with Telegram markdown
    - Forum topics (thread_id support)
    - Media messages
    """
    
    # Telegram message limits
    MAX_MESSAGE_LENGTH = 4096
    # Threshold for detecting Telegram client-side message splits.
    # When a chunk is near this limit, a continuation is almost certain.
    _SPLIT_THRESHOLD = 4000
    MEDIA_GROUP_WAIT_SECONDS = 0.8
    
    def __init__(self, config: PlatformConfig):
        super().__init__(config, Platform.TELEGRAM)
        self._app: Optional[Application] = None
        self._bot: Optional[Bot] = None
        self._webhook_mode: bool = False
        self._mention_patterns = self._compile_mention_patterns()
        self._reply_to_mode: str = getattr(config, 'reply_to_mode', 'first') or 'first'
        # Buffer rapid/album photo updates so Telegram image bursts are handled
        # as a single MessageEvent instead of self-interrupting multiple turns.
        self._media_batch_delay_seconds = float(os.getenv("HERMES_TELEGRAM_MEDIA_BATCH_DELAY_SECONDS", "0.8"))
        self._pending_photo_batches: Dict[str, MessageEvent] = {}
        self._pending_photo_batch_tasks: Dict[str, asyncio.Task] = {}
        self._media_group_events: Dict[str, MessageEvent] = {}
        self._media_group_tasks: Dict[str, asyncio.Task] = {}
        # Buffer rapid text messages so Telegram client-side splits of long
        # messages are aggregated into a single MessageEvent.
        self._text_batch_delay_seconds = float(os.getenv("HERMES_TELEGRAM_TEXT_BATCH_DELAY_SECONDS", "0.6"))
        self._text_batch_split_delay_seconds = float(os.getenv("HERMES_TELEGRAM_TEXT_BATCH_SPLIT_DELAY_SECONDS", "2.0"))
        self._pending_text_batches: Dict[str, MessageEvent] = {}
        self._pending_text_batch_tasks: Dict[str, asyncio.Task] = {}
        self._polling_error_task: Optional[asyncio.Task] = None
        self._polling_conflict_count: int = 0
        self._polling_network_error_count: int = 0
        self._polling_error_callback_ref = None
        # DM Topics: map of topic_name -> message_thread_id (populated at startup)
        self._dm_topics: Dict[str, int] = {}
        # DM Topics config from extra.dm_topics
        self._dm_topics_config: List[Dict[str, Any]] = self.config.extra.get("dm_topics", [])
        # Interactive model picker state per chat
        self._model_picker_state: Dict[str, dict] = {}
        # Approval button state: message_id → session_key
        self._approval_state: Dict[int, str] = {}

    def _fallback_ips(self) -> list[str]:
        """Return validated fallback IPs from config (populated by _apply_env_overrides)."""
        configured = self.config.extra.get("fallback_ips", []) if getattr(self.config, "extra", None) else []
        if isinstance(configured, str):
            configured = configured.split(",")
        return parse_fallback_ip_env(",".join(str(v) for v in configured) if configured else None)

    @staticmethod
    def _looks_like_polling_conflict(error: Exception) -> bool:
        text = str(error).lower()
        return (
            error.__class__.__name__.lower() == "conflict"
            or "terminated by other getupdates request" in text
            or "another bot instance is running" in text
        )

    @staticmethod
    def _looks_like_network_error(error: Exception) -> bool:
        """Return True for transient network errors that warrant a reconnect attempt."""
        name = error.__class__.__name__.lower()
        if name in ("networkerror", "timedout", "connectionerror"):
            return True
        try:
            from telegram.error import NetworkError, TimedOut
            if isinstance(error, (NetworkError, TimedOut)):
                return True
        except ImportError:
            pass
        return isinstance(error, OSError)

    async def _handle_polling_network_error(self, error: Exception) -> None:
        """Reconnect polling after a transient network interruption.

        Triggered by NetworkError/TimedOut in the polling error callback, which
        happen when the host loses connectivity (Mac sleep, WiFi switch, VPN
        reconnect, etc.).  The gateway process stays alive but the long-poll
        connection silently dies; without this handler the bot never recovers.

        Strategy: exponential back-off (5s, 10s, 20s, 40s, 60s cap) up to
        MAX_NETWORK_RETRIES attempts, then mark the adapter retryable-fatal so
        the supervisor restarts the gateway process.
        """
        if self.has_fatal_error:
            return

        MAX_NETWORK_RETRIES = 10
        BASE_DELAY = 5
        MAX_DELAY = 60

        self._polling_network_error_count += 1
        attempt = self._polling_network_error_count

        if attempt > MAX_NETWORK_RETRIES:
            message = (
                "Telegram polling could not reconnect after %d network error retries. "
                "Restarting gateway." % MAX_NETWORK_RETRIES
            )
            logger.error("[%s] %s Last error: %s", self.name, message, error)
            self._set_fatal_error("telegram_network_error", message, retryable=True)
            await self._notify_fatal_error()
            return

        delay = min(BASE_DELAY * (2 ** (attempt - 1)), MAX_DELAY)
        logger.warning(
            "[%s] Telegram network error (attempt %d/%d), reconnecting in %ds. Error: %s",
            self.name, attempt, MAX_NETWORK_RETRIES, delay, error,
        )
        await asyncio.sleep(delay)

        try:
            if self._app and self._app.updater and self._app.updater.running:
                await self._app.updater.stop()
        except Exception:
            pass

        try:
            await self._app.updater.start_polling(
                allowed_updates=Update.ALL_TYPES,
                drop_pending_updates=False,
                error_callback=self._polling_error_callback_ref,
            )
            logger.info(
                "[%s] Telegram polling resumed after network error (attempt %d)",
                self.name, attempt,
            )
            self._polling_network_error_count = 0
        except Exception as retry_err:
            logger.warning("[%s] Telegram polling reconnect failed: %s", self.name, retry_err)
            # start_polling failed — polling is dead and no further error
            # callbacks will fire, so schedule the next retry ourselves.
            if not self.has_fatal_error:
                task = asyncio.ensure_future(
                    self._handle_polling_network_error(retry_err)
                )
                self._background_tasks.add(task)
                task.add_done_callback(self._background_tasks.discard)

    async def _handle_polling_conflict(self, error: Exception) -> None:
        if self.has_fatal_error and self.fatal_error_code == "telegram_polling_conflict":
            return
        # Track consecutive conflicts — transient 409s can occur when a
        # previous gateway instance hasn't fully released its long-poll
        # session on Telegram's server (e.g. during --replace handoffs or
        # systemd Restart=on-failure respawns).  Retry a few times before
        # giving up, so the old session has time to expire.
        self._polling_conflict_count += 1

        MAX_CONFLICT_RETRIES = 3
        RETRY_DELAY = 10  # seconds

        if self._polling_conflict_count <= MAX_CONFLICT_RETRIES:
            logger.warning(
                "[%s] Telegram polling conflict (%d/%d), will retry in %ds. Error: %s",
                self.name, self._polling_conflict_count, MAX_CONFLICT_RETRIES,
                RETRY_DELAY, error,
            )
            try:
                if self._app and self._app.updater and self._app.updater.running:
                    await self._app.updater.stop()
            except Exception:
                pass
            await asyncio.sleep(RETRY_DELAY)
            try:
                await self._app.updater.start_polling(
                    allowed_updates=Update.ALL_TYPES,
                    drop_pending_updates=False,
                    error_callback=self._polling_error_callback_ref,
                )
                logger.info("[%s] Telegram polling resumed after conflict retry %d", self.name, self._polling_conflict_count)
                self._polling_conflict_count = 0  # reset on success
                return
            except Exception as retry_err:
                logger.warning("[%s] Telegram polling retry failed: %s", self.name, retry_err)
                # Don't fall through to fatal yet — wait for the next conflict
                # to trigger another retry attempt (up to MAX_CONFLICT_RETRIES).
                return

        # Exhausted retries — fatal
        message = (
            "Another process is already polling this Telegram bot token "
            "(possibly OpenClaw or another Hermes instance). "
            "Hermes stopped Telegram polling after %d retries. "
            "Only one poller can run per token — stop the other process "
            "and restart with 'hermes start'."
            % MAX_CONFLICT_RETRIES
        )
        logger.error("[%s] %s Original error: %s", self.name, message, error)
        self._set_fatal_error("telegram_polling_conflict", message, retryable=False)
        try:
            if self._app and self._app.updater:
                await self._app.updater.stop()
        except Exception as stop_error:
            logger.warning("[%s] Failed stopping Telegram polling after conflict: %s", self.name, stop_error, exc_info=True)
        await self._notify_fatal_error()

    async def _create_dm_topic(
        self,
        chat_id: int,
        name: str,
        icon_color: Optional[int] = None,
        icon_custom_emoji_id: Optional[str] = None,
    ) -> Optional[int]:
        """Create a forum topic in a private (DM) chat.

        Uses Bot API 9.4's createForumTopic which now works for 1-on-1 chats.
        Returns the message_thread_id on success, None on failure.
        """
        if not self._bot:
            return None
        try:
            kwargs: Dict[str, Any] = {"chat_id": chat_id, "name": name}
            if icon_color is not None:
                kwargs["icon_color"] = icon_color
            if icon_custom_emoji_id:
                kwargs["icon_custom_emoji_id"] = icon_custom_emoji_id

            topic = await self._bot.create_forum_topic(**kwargs)
            thread_id = topic.message_thread_id
            logger.info(
                "[%s] Created DM topic '%s' in chat %s -> thread_id=%s",
                self.name, name, chat_id, thread_id,
            )
            return thread_id
        except Exception as e:
            error_text = str(e).lower()
            # If topic already exists, try to find it via getForumTopicIconStickers
            # or we just log and skip — Telegram doesn't provide a "list topics" API
            if "topic_name_duplicate" in error_text or "already" in error_text:
                logger.info(
                    "[%s] DM topic '%s' already exists in chat %s (will be mapped from incoming messages)",
                    self.name, name, chat_id,
                )
            else:
                logger.warning(
                    "[%s] Failed to create DM topic '%s' in chat %s: %s",
                    self.name, name, chat_id, e,
                )
            return None

    def _persist_dm_topic_thread_id(self, chat_id: int, topic_name: str, thread_id: int) -> None:
        """Save a newly created thread_id back into config.yaml so it persists across restarts."""
        try:
            from hermes_constants import get_hermes_home
            config_path = get_hermes_home() / "config.yaml"
            if not config_path.exists():
                logger.warning("[%s] Config file not found at %s, cannot persist thread_id", self.name, config_path)
                return

            import yaml as _yaml
            with open(config_path, "r") as f:
                config = _yaml.safe_load(f) or {}

            # Navigate to platforms.telegram.extra.dm_topics
            dm_topics = (
                config.get("platforms", {})
                .get("telegram", {})
                .get("extra", {})
                .get("dm_topics", [])
            )
            if not dm_topics:
                return

            changed = False
            for chat_entry in dm_topics:
                if int(chat_entry.get("chat_id", 0)) != int(chat_id):
                    continue
                for t in chat_entry.get("topics", []):
                    if t.get("name") == topic_name and not t.get("thread_id"):
                        t["thread_id"] = thread_id
                        changed = True
                        break

            if changed:
                with open(config_path, "w") as f:
                    _yaml.dump(config, f, default_flow_style=False, sort_keys=False)
                logger.info(
                    "[%s] Persisted thread_id=%s for topic '%s' in config.yaml",
                    self.name, thread_id, topic_name,
                )
        except Exception as e:
            logger.warning("[%s] Failed to persist thread_id to config: %s", self.name, e, exc_info=True)

    async def _setup_dm_topics(self) -> None:
        """Load or create configured DM topics for specified chats.

        Reads config.extra['dm_topics'] — a list of dicts:
        [
            {
                "chat_id": 123456789,
                "topics": [
                    {"name": "General", "icon_color": 7322096, "thread_id": 100},
                    {"name": "Accessibility Auditor", "icon_color": 9367192, "skill": "accessibility-auditor"}
                ]
            }
        ]

        If a topic already has a thread_id in the config (persisted from a previous
        creation), it is loaded into the cache without calling createForumTopic.
        Only topics without a thread_id are created via the API, and their thread_id
        is then saved back to config.yaml for future restarts.
        """
        if not self._dm_topics_config:
            return

        for chat_entry in self._dm_topics_config:
            chat_id = chat_entry.get("chat_id")
            topics = chat_entry.get("topics", [])
            if not chat_id or not topics:
                continue

            logger.info(
                "[%s] Setting up %d DM topic(s) for chat %s",
                self.name, len(topics), chat_id,
            )

            for topic_conf in topics:
                topic_name = topic_conf.get("name")
                if not topic_name:
                    continue

                cache_key = f"{chat_id}:{topic_name}"

                # If thread_id is already persisted in config, just load into cache
                existing_thread_id = topic_conf.get("thread_id")
                if existing_thread_id:
                    self._dm_topics[cache_key] = int(existing_thread_id)
                    logger.info(
                        "[%s] DM topic loaded from config: %s -> thread_id=%s",
                        self.name, cache_key, existing_thread_id,
                    )
                    continue

                # No persisted thread_id — create the topic via API
                icon_color = topic_conf.get("icon_color")
                icon_emoji = topic_conf.get("icon_custom_emoji_id")

                thread_id = await self._create_dm_topic(
                    chat_id=int(chat_id),
                    name=topic_name,
                    icon_color=icon_color,
                    icon_custom_emoji_id=icon_emoji,
                )

                if thread_id:
                    self._dm_topics[cache_key] = thread_id
                    logger.info(
                        "[%s] DM topic cached: %s -> thread_id=%s",
                        self.name, cache_key, thread_id,
                    )
                    # Persist thread_id to config so we don't recreate on next restart
                    self._persist_dm_topic_thread_id(int(chat_id), topic_name, thread_id)

    async def connect(self) -> bool:
        """Connect to Telegram via polling or webhook.

        By default, uses long polling (outbound connection to Telegram).
        If ``TELEGRAM_WEBHOOK_URL`` is set, starts an HTTP webhook server
        instead.  Webhook mode is useful for cloud deployments (Fly.io,
        Railway) where inbound HTTP can wake a suspended machine.

        Env vars for webhook mode::

            TELEGRAM_WEBHOOK_URL    Public HTTPS URL (e.g. https://app.fly.dev/telegram)
            TELEGRAM_WEBHOOK_PORT   Local listen port (default 8443)
            TELEGRAM_WEBHOOK_SECRET Secret token for update verification
        """
        if not TELEGRAM_AVAILABLE:
            logger.error(
                "[%s] python-telegram-bot not installed. Run: pip install python-telegram-bot",
                self.name,
            )
            return False
        
        if not self.config.token:
            logger.error("[%s] No bot token configured", self.name)
            return False
        
        try:
            if not self._acquire_platform_lock('telegram-bot-token', self.config.token, 'Telegram bot token'):
                return False

            # Build the application
            builder = Application.builder().token(self.config.token)
            custom_base_url = self.config.extra.get("base_url")
            if custom_base_url:
                builder = builder.base_url(custom_base_url)
                builder = builder.base_file_url(
                    self.config.extra.get("base_file_url", custom_base_url)
                )
                logger.info(
                    "[%s] Using custom Telegram base_url: %s",
                    self.name, custom_base_url,
                )

            # PTB defaults (pool_timeout=1s) are too aggressive on flaky networks and
            # can trigger "Pool timeout: All connections in the connection pool are occupied"
            # during reconnect/bootstrap. Use safer defaults and allow env overrides.
            def _env_int(name: str, default: int) -> int:
                try:
                    return int(os.getenv(name, str(default)))
                except (TypeError, ValueError):
                    return default

            def _env_float(name: str, default: float) -> float:
                try:
                    return float(os.getenv(name, str(default)))
                except (TypeError, ValueError):
                    return default

            request_kwargs = {
                "connection_pool_size": _env_int("HERMES_TELEGRAM_HTTP_POOL_SIZE", 512),
                "pool_timeout": _env_float("HERMES_TELEGRAM_HTTP_POOL_TIMEOUT", 8.0),
                "connect_timeout": _env_float("HERMES_TELEGRAM_HTTP_CONNECT_TIMEOUT", 10.0),
                "read_timeout": _env_float("HERMES_TELEGRAM_HTTP_READ_TIMEOUT", 20.0),
                "write_timeout": _env_float("HERMES_TELEGRAM_HTTP_WRITE_TIMEOUT", 20.0),
            }

            proxy_url = resolve_proxy_url()
            disable_fallback = (os.getenv("HERMES_TELEGRAM_DISABLE_FALLBACK_IPS", "").strip().lower() in ("1", "true", "yes", "on"))
            fallback_ips = self._fallback_ips()
            if not fallback_ips:
                fallback_ips = await discover_fallback_ips()
                logger.info(
                    "[%s] Auto-discovered Telegram fallback IPs: %s",
                    self.name,
                    ", ".join(fallback_ips),
                )

            if fallback_ips and not proxy_url and not disable_fallback:
                logger.info(
                    "[%s] Telegram fallback IPs active: %s",
                    self.name,
                    ", ".join(fallback_ips),
                )
                # Keep request/update pools separate to reduce contention during
                # polling reconnect + bot API bootstrap/delete_webhook calls.
                request = HTTPXRequest(
                    **request_kwargs,
                    httpx_kwargs={"transport": TelegramFallbackTransport(fallback_ips)},
                )
                get_updates_request = HTTPXRequest(
                    **request_kwargs,
                    httpx_kwargs={"transport": TelegramFallbackTransport(fallback_ips)},
                )
            elif proxy_url:
                logger.info("[%s] Proxy detected; passing explicitly to HTTPXRequest: %s", self.name, proxy_url)
                request = HTTPXRequest(**request_kwargs, proxy=proxy_url)
                get_updates_request = HTTPXRequest(**request_kwargs, proxy=proxy_url)
            else:
                if disable_fallback:
                    logger.info("[%s] Telegram fallback-IP transport disabled via env", self.name)
                request = HTTPXRequest(**request_kwargs)
                get_updates_request = HTTPXRequest(**request_kwargs)

            builder = builder.request(request).get_updates_request(get_updates_request)
            self._app = builder.build()
            self._bot = self._app.bot
            
            # Register handlers
            self._app.add_handler(TelegramMessageHandler(
                filters.TEXT & ~filters.COMMAND,
                self._handle_text_message
            ))
            self._app.add_handler(TelegramMessageHandler(
                filters.COMMAND,
                self._handle_command
            ))
            self._app.add_handler(TelegramMessageHandler(
                filters.LOCATION | getattr(filters, "VENUE", filters.LOCATION),
                self._handle_location_message
            ))
            self._app.add_handler(TelegramMessageHandler(
                filters.PHOTO | filters.VIDEO | filters.AUDIO | filters.VOICE | filters.Document.ALL | filters.Sticker.ALL,
                self._handle_media_message
            ))
            # Handle inline keyboard button callbacks (update prompts)
            self._app.add_handler(CallbackQueryHandler(self._handle_callback_query))
            
            # Start polling — retry initialize() for transient TLS resets
            try:
                from telegram.error import NetworkError, TimedOut
            except ImportError:
                NetworkError = TimedOut = OSError  # type: ignore[misc,assignment]
            _max_connect = 3
            for _attempt in range(_max_connect):
                try:
                    await self._app.initialize()
                    break
                except (NetworkError, TimedOut, OSError) as init_err:
                    if _attempt < _max_connect - 1:
                        wait = 2 ** _attempt
                        logger.warning(
                            "[%s] Connect attempt %d/%d failed: %s — retrying in %ds",
                            self.name, _attempt + 1, _max_connect, init_err, wait,
                        )
                        await asyncio.sleep(wait)
                    else:
                        raise
            await self._app.start()

            # Decide between webhook and polling mode
            webhook_url = os.getenv("TELEGRAM_WEBHOOK_URL", "").strip()

            if webhook_url:
                # ── Webhook mode ─────────────────────────────────────
                # Telegram pushes updates to our HTTP endpoint.  This
                # enables cloud platforms (Fly.io, Railway) to auto-wake
                # suspended machines on inbound HTTP traffic.
                webhook_port = int(os.getenv("TELEGRAM_WEBHOOK_PORT", "8443"))
                webhook_secret = os.getenv("TELEGRAM_WEBHOOK_SECRET", "").strip() or None
                from urllib.parse import urlparse
                webhook_path = urlparse(webhook_url).path or "/telegram"

                await self._app.updater.start_webhook(
                    listen="0.0.0.0",
                    port=webhook_port,
                    url_path=webhook_path,
                    webhook_url=webhook_url,
                    secret_token=webhook_secret,
                    allowed_updates=Update.ALL_TYPES,
                    drop_pending_updates=True,
                )
                self._webhook_mode = True
                logger.info(
                    "[%s] Webhook server listening on 0.0.0.0:%d%s",
                    self.name, webhook_port, webhook_path,
                )
            else:
                # ── Polling mode (default) ───────────────────────────
                # Clear any stale webhook first so polling doesn't inherit a
                # previous webhook registration and silently stop receiving updates.
                delete_webhook = getattr(self._bot, "delete_webhook", None)
                if callable(delete_webhook):
                    await delete_webhook(drop_pending_updates=False)

                loop = asyncio.get_running_loop()

                def _polling_error_callback(error: Exception) -> None:
                    if self._polling_error_task and not self._polling_error_task.done():
                        return
                    if self._looks_like_polling_conflict(error):
                        self._polling_error_task = loop.create_task(self._handle_polling_conflict(error))
                    elif self._looks_like_network_error(error):
                        logger.warning("[%s] Telegram network error, scheduling reconnect: %s", self.name, error)
                        self._polling_error_task = loop.create_task(self._handle_polling_network_error(error))
                    else:
                        logger.error("[%s] Telegram polling error: %s", self.name, error, exc_info=True)

                # Store reference for retry use in _handle_polling_conflict
                self._polling_error_callback_ref = _polling_error_callback

                await self._app.updater.start_polling(
                    allowed_updates=Update.ALL_TYPES,
                    drop_pending_updates=True,
                    error_callback=_polling_error_callback,
                )
            
            # Register bot commands so Telegram shows a hint menu when users type /
            # List is derived from the central COMMAND_REGISTRY — adding a new
            # gateway command there automatically adds it to the Telegram menu.
            try:
                from telegram import BotCommand
                from hermes_cli.commands import telegram_menu_commands
                # Telegram allows up to 100 commands but has an undocumented
                # payload size limit.  Skill descriptions are truncated to 40
                # chars in telegram_menu_commands() to fit 100 commands safely.
                menu_commands, hidden_count = telegram_menu_commands(max_commands=100)
                await self._bot.set_my_commands([
                    BotCommand(name, desc) for name, desc in menu_commands
                ])
                if hidden_count:
                    logger.info(
                        "[%s] Telegram menu: %d commands registered, %d hidden (over 100 limit). Use /commands for full list.",
                        self.name, len(menu_commands), hidden_count,
                    )
            except Exception as e:
                logger.warning(
                    "[%s] Could not register Telegram command menu: %s",
                    self.name,
                    e,
                    exc_info=True,
                )
            
            self._mark_connected()
            mode = "webhook" if self._webhook_mode else "polling"
            logger.info("[%s] Connected to Telegram (%s mode)", self.name, mode)

            # Set up DM topics (Bot API 9.4 — Private Chat Topics)
            # Runs after connection is established so the bot can call createForumTopic.
            # Failures here are non-fatal — the bot works fine without topics.
            try:
                await self._setup_dm_topics()
            except Exception as topics_err:
                logger.warning(
                    "[%s] DM topics setup failed (non-fatal): %s",
                    self.name, topics_err, exc_info=True,
                )

            return True
            
        except Exception as e:
            self._release_platform_lock()
            message = f"Telegram startup failed: {e}"
            self._set_fatal_error("telegram_connect_error", message, retryable=True)
            logger.error("[%s] Failed to connect to Telegram: %s", self.name, e, exc_info=True)
            return False
    
    async def disconnect(self) -> None:
        """Stop polling/webhook, cancel pending album flushes, and disconnect."""
        pending_media_group_tasks = list(self._media_group_tasks.values())
        for task in pending_media_group_tasks:
            task.cancel()
        if pending_media_group_tasks:
            await asyncio.gather(*pending_media_group_tasks, return_exceptions=True)
        self._media_group_tasks.clear()
        self._media_group_events.clear()

        if self._app:
            try:
                # Only stop the updater if it's running
                if self._app.updater and self._app.updater.running:
                    await self._app.updater.stop()
                if self._app.running:
                    await self._app.stop()
                await self._app.shutdown()
            except Exception as e:
                logger.warning("[%s] Error during Telegram disconnect: %s", self.name, e, exc_info=True)
        self._release_platform_lock()

        for task in self._pending_photo_batch_tasks.values():
            if task and not task.done():
                task.cancel()
        self._pending_photo_batch_tasks.clear()
        self._pending_photo_batches.clear()

        self._mark_disconnected()
        self._app = None
        self._bot = None
        logger.info("[%s] Disconnected from Telegram", self.name)

    def _should_thread_reply(self, reply_to: Optional[str], chunk_index: int) -> bool:
        """Determine if this message chunk should thread to the original message.

        Args:
            reply_to: The original message ID to reply to
            chunk_index: Index of this chunk (0 = first chunk)

        Returns:
            True if this chunk should be threaded to the original message
        """
        if not reply_to:
            return False
        mode = self._reply_to_mode
        if mode == "off":
            return False
        elif mode == "all":
            return True
        else:  # "first" (default)
            return chunk_index == 0

    async def send(
        self,
        chat_id: str,
        content: str,
        reply_to: Optional[str] = None,
        metadata: Optional[Dict[str, Any]] = None
    ) -> SendResult:
        """Send a message to a Telegram chat."""
        if not self._bot:
            return SendResult(success=False, error="Not connected")
        
        # Skip whitespace-only text to prevent Telegram 400 empty-text errors.
        if not content or not content.strip():
            return SendResult(success=True, message_id=None)
        
        try:
            # Format and split message if needed
            formatted = self.format_message(content)
            chunks = self.truncate_message(
                formatted, self.MAX_MESSAGE_LENGTH, len_fn=utf16_len,
            )
            if len(chunks) > 1:
                # truncate_message appends a raw " (1/2)" suffix. Escape the
                # MarkdownV2-special parentheses so Telegram doesn't reject the
                # chunk and fall back to plain text.
                chunks = [
                    re.sub(r" \((\d+)/(\d+)\)$", r" \\(\1/\2\\)", chunk)
                    for chunk in chunks
                ]
            
            message_ids = []
            thread_id = metadata.get("thread_id") if metadata else None
            
            try:
                from telegram.error import NetworkError as _NetErr
            except ImportError:
                _NetErr = OSError  # type: ignore[misc,assignment]

            try:
                from telegram.error import BadRequest as _BadReq
            except ImportError:
                _BadReq = None  # type: ignore[assignment,misc]

            try:
                from telegram.error import TimedOut as _TimedOut
            except (ImportError, AttributeError):
                _TimedOut = None  # type: ignore[assignment,misc]

            for i, chunk in enumerate(chunks):
                should_thread = self._should_thread_reply(reply_to, i)
                reply_to_id = int(reply_to) if should_thread else None
                effective_thread_id = int(thread_id) if thread_id else None

                msg = None
                for _send_attempt in range(3):
                    try:
                        # Try Markdown first, fall back to plain text if it fails
                        try:
                            msg = await self._bot.send_message(
                                chat_id=int(chat_id),
                                text=chunk,
                                parse_mode=ParseMode.MARKDOWN_V2,
                                reply_to_message_id=reply_to_id,
                                message_thread_id=effective_thread_id,
                            )
                        except Exception as md_error:
                            # Markdown parsing failed, try plain text
                            if "parse" in str(md_error).lower() or "markdown" in str(md_error).lower():
                                logger.warning("[%s] MarkdownV2 parse failed, falling back to plain text: %s", self.name, md_error)
                                plain_chunk = _strip_mdv2(chunk)
                                msg = await self._bot.send_message(
                                    chat_id=int(chat_id),
                                    text=plain_chunk,
                                    parse_mode=None,
                                    reply_to_message_id=reply_to_id,
                                    message_thread_id=effective_thread_id,
                                )
                            else:
                                raise
                        break  # success
                    except _NetErr as send_err:
                        # BadRequest is a subclass of NetworkError in
                        # python-telegram-bot but represents permanent errors
                        # (not transient network issues). Detect and handle
                        # specific cases instead of blindly retrying.
                        if _BadReq and isinstance(send_err, _BadReq):
                            err_lower = str(send_err).lower()
                            if "thread not found" in err_lower and effective_thread_id is not None:
                                # Thread doesn't exist — retry without
                                # message_thread_id so the message still
                                # reaches the chat.
                                logger.warning(
                                    "[%s] Thread %s not found, retrying without message_thread_id",
                                    self.name, effective_thread_id,
                                )
                                effective_thread_id = None
                                continue
                            if "message to be replied not found" in err_lower and reply_to_id is not None:
                                # Original message was deleted before we
                                # could reply — clear reply target and retry
                                # so the response is still delivered.
                                logger.warning(
                                    "[%s] Reply target deleted, retrying without reply_to: %s",
                                    self.name, send_err,
                                )
                                reply_to_id = None
                                continue
                            # Other BadRequest errors are permanent — don't retry
                            raise
                        # TimedOut is also a subclass of NetworkError but
                        # indicates the request may have reached the server —
                        # retrying risks duplicate message delivery.
                        if _TimedOut and isinstance(send_err, _TimedOut):
                            raise
                        if _send_attempt < 2:
                            wait = 2 ** _send_attempt
                            logger.warning("[%s] Network error on send (attempt %d/3), retrying in %ds: %s",
                                           self.name, _send_attempt + 1, wait, send_err)
                            await asyncio.sleep(wait)
                        else:
                            raise
                    except Exception as send_err:
                        retry_after = getattr(send_err, "retry_after", None)
                        if retry_after is not None or "retry after" in str(send_err).lower():
                            if _send_attempt < 2:
                                wait = float(retry_after) if retry_after is not None else 1.0
                                logger.warning(
                                    "[%s] Telegram flood control on send (attempt %d/3), retrying in %.1fs: %s",
                                    self.name,
                                    _send_attempt + 1,
                                    wait,
                                    send_err,
                                )
                                await asyncio.sleep(wait)
                                continue
                        raise
                message_ids.append(str(msg.message_id))
            
            return SendResult(
                success=True,
                message_id=message_ids[0] if message_ids else None,
                raw_response={"message_ids": message_ids}
            )
            
        except Exception as e:
            logger.error("[%s] Failed to send Telegram message: %s", self.name, e, exc_info=True)
            # TimedOut means the request may have reached Telegram —
            # mark as non-retryable so _send_with_retry() doesn't re-send.
            _to = locals().get("_TimedOut")
            err_str = str(e).lower()
            is_timeout = (_to and isinstance(e, _to)) or "timed out" in err_str
            return SendResult(success=False, error=str(e), retryable=not is_timeout)

    async def edit_message(
        self,
        chat_id: str,
        message_id: str,
        content: str,
    ) -> SendResult:
        """Edit a previously sent Telegram message."""
        if not self._bot:
            return SendResult(success=False, error="Not connected")
        try:
            formatted = self.format_message(content)
            try:
                await self._bot.edit_message_text(
                    chat_id=int(chat_id),
                    message_id=int(message_id),
                    text=formatted,
                    parse_mode=ParseMode.MARKDOWN_V2,
                )
            except Exception as fmt_err:
                # "Message is not modified" is a no-op, not an error
                if "not modified" in str(fmt_err).lower():
                    return SendResult(success=True, message_id=message_id)
                # Fallback: retry without markdown formatting
                await self._bot.edit_message_text(
                    chat_id=int(chat_id),
                    message_id=int(message_id),
                    text=content,
                )
            return SendResult(success=True, message_id=message_id)
        except Exception as e:
            err_str = str(e).lower()
            # "Message is not modified" — content identical, treat as success
            if "not modified" in err_str:
                return SendResult(success=True, message_id=message_id)
            # Message too long — content exceeded 4096 chars (e.g. during
            # streaming).  Truncate and succeed so the stream consumer can
            # split the overflow into a new message instead of dying.
            if "message_too_long" in err_str or "too long" in err_str:
                truncated = _prefix_within_utf16_limit(
                    content, self.MAX_MESSAGE_LENGTH - 20
                ) + "…"
                try:
                    await self._bot.edit_message_text(
                        chat_id=int(chat_id),
                        message_id=int(message_id),
                        text=truncated,
                    )
                except Exception:
                    pass  # best-effort truncation
                return SendResult(success=True, message_id=message_id)
            # Flood control / RetryAfter — short waits are retried inline,
            # long waits return a failure immediately so streaming can fall back
            # to a normal final send instead of leaving a truncated partial.
            retry_after = getattr(e, "retry_after", None)
            if retry_after is not None or "retry after" in err_str:
                wait = retry_after if retry_after else 1.0
                logger.warning(
                    "[%s] Telegram flood control, waiting %.1fs",
                    self.name, wait,
                )
                if wait > 5.0:
                    return SendResult(success=False, error=f"flood_control:{wait}")
                await asyncio.sleep(wait)
                try:
                    await self._bot.edit_message_text(
                        chat_id=int(chat_id),
                        message_id=int(message_id),
                        text=content,
                    )
                    return SendResult(success=True, message_id=message_id)
                except Exception as retry_err:
                    logger.error(
                        "[%s] Edit retry failed after flood wait: %s",
                        self.name, retry_err,
                    )
                    return SendResult(success=False, error=str(retry_err))
            logger.error(
                "[%s] Failed to edit Telegram message %s: %s",
                self.name,
                message_id,
                e,
                exc_info=True,
            )
            return SendResult(success=False, error=str(e))

    async def send_update_prompt(
        self, chat_id: str, prompt: str, default: str = "",
        session_key: str = "",
    ) -> SendResult:
        """Send an inline-keyboard update prompt (Yes / No buttons).

        Used by the gateway ``/update`` watcher when ``hermes update --gateway``
        needs user input (stash restore, config migration).
        """
        if not self._bot:
            return SendResult(success=False, error="Not connected")
        try:
            default_hint = f" (default: {default})" if default else ""
            text = f"⚕ *Update needs your input:*\n\n{prompt}{default_hint}"
            keyboard = InlineKeyboardMarkup([
                [
                    InlineKeyboardButton("✓ Yes", callback_data="update_prompt:y"),
                    InlineKeyboardButton("✗ No", callback_data="update_prompt:n"),
                ]
            ])
            msg = await self._bot.send_message(
                chat_id=int(chat_id),
                text=text,
                parse_mode=ParseMode.MARKDOWN,
                reply_markup=keyboard,
            )
            return SendResult(success=True, message_id=str(msg.message_id))
        except Exception as e:
            logger.warning("[%s] send_update_prompt failed: %s", self.name, e)
            return SendResult(success=False, error=str(e))

    async def send_exec_approval(
        self, chat_id: str, command: str, session_key: str,
        description: str = "dangerous command",
        metadata: Optional[Dict[str, Any]] = None,
    ) -> SendResult:
        """Send an inline-keyboard approval prompt with interactive buttons.

        The buttons call ``resolve_gateway_approval()`` to unblock the waiting
        agent thread — same mechanism as the text ``/approve`` flow.
        """
        if not self._bot:
            return SendResult(success=False, error="Not connected")

        try:
            cmd_preview = command[:3800] + "..." if len(command) > 3800 else command
            text = (
                f"⚠️ *Command Approval Required*\n\n"
                f"`{cmd_preview}`\n\n"
                f"Reason: {description}"
            )

            # Resolve thread context for thread replies
            thread_id = None
            if metadata:
                thread_id = metadata.get("thread_id") or metadata.get("message_thread_id")

            # We'll use the message_id as part of callback_data to look up session_key
            # Send a placeholder first, then update — or use a counter.
            # Simpler: use a monotonic counter to generate short IDs.
            import itertools
            if not hasattr(self, "_approval_counter"):
                self._approval_counter = itertools.count(1)
            approval_id = next(self._approval_counter)

            keyboard = InlineKeyboardMarkup([
                [
                    InlineKeyboardButton("✅ Allow Once", callback_data=f"ea:once:{approval_id}"),
                    InlineKeyboardButton("✅ Session", callback_data=f"ea:session:{approval_id}"),
                ],
                [
                    InlineKeyboardButton("✅ Always", callback_data=f"ea:always:{approval_id}"),
                    InlineKeyboardButton("❌ Deny", callback_data=f"ea:deny:{approval_id}"),
                ],
            ])

            kwargs: Dict[str, Any] = {
                "chat_id": int(chat_id),
                "text": text,
                "parse_mode": ParseMode.MARKDOWN,
                "reply_markup": keyboard,
            }
            if thread_id:
                kwargs["message_thread_id"] = int(thread_id)

            msg = await self._bot.send_message(**kwargs)

            # Store session_key keyed by approval_id for the callback handler
            self._approval_state[approval_id] = session_key

            return SendResult(success=True, message_id=str(msg.message_id))
        except Exception as e:
            logger.warning("[%s] send_exec_approval failed: %s", self.name, e)
            return SendResult(success=False, error=str(e))

    async def send_model_picker(
        self,
        chat_id: str,
        providers: list,
        current_model: str,
        current_provider: str,
        session_key: str,
        on_model_selected,
        metadata: Optional[Dict[str, Any]] = None,
    ) -> SendResult:
        """Send an interactive inline-keyboard model picker.

        Two-step drill-down: provider selection → model selection.
        Edits the same message in-place as the user navigates.
        """
        if not self._bot:
            return SendResult(success=False, error="Not connected")

        try:
            from hermes_cli.providers import get_label
        except ImportError:
            def get_label(slug):
                return slug

        try:
            # Build provider buttons — 2 per row
            buttons: list = []
            for p in providers:
                count = p.get("total_models", len(p.get("models", [])))
                label = f"{p['name']} ({count})"
                if p.get("is_current"):
                    label = f"✓ {label}"
                # Compact callback data: mp:<slug>  (max 64 bytes)
                buttons.append(
                    InlineKeyboardButton(label, callback_data=f"mp:{p['slug']}")
                )

            rows = [buttons[i : i + 2] for i in range(0, len(buttons), 2)]
            rows.append([InlineKeyboardButton("✗ Cancel", callback_data="mx")])
            keyboard = InlineKeyboardMarkup(rows)

            provider_label = get_label(current_provider)
            text = (
                f"⚙ *Model Configuration*\n\n"
                f"Current model: `{current_model or 'unknown'}`\n"
                f"Provider: {provider_label}\n\n"
                f"Select a provider:"
            )

            thread_id = metadata.get("thread_id") if metadata else None
            msg = await self._bot.send_message(
                chat_id=int(chat_id),
                text=text,
                parse_mode=ParseMode.MARKDOWN,
                reply_markup=keyboard,
                message_thread_id=int(thread_id) if thread_id else None,
            )

            # Store picker state keyed by chat_id
            self._model_picker_state[str(chat_id)] = {
                "msg_id": msg.message_id,
                "providers": providers,
                "session_key": session_key,
                "on_model_selected": on_model_selected,
                "current_model": current_model,
                "current_provider": current_provider,
            }

            return SendResult(success=True, message_id=str(msg.message_id))
        except Exception as e:
            logger.warning("[%s] send_model_picker failed: %s", self.name, e)
            return SendResult(success=False, error=str(e))

    _MODEL_PAGE_SIZE = 8

    def _build_model_keyboard(self, models: list, page: int) -> tuple:
        """Build paginated model buttons. Returns (keyboard, page_info_text)."""
        page_size = self._MODEL_PAGE_SIZE
        total = len(models)
        total_pages = max(1, (total + page_size - 1) // page_size)
        page = max(0, min(page, total_pages - 1))

        start = page * page_size
        end = min(start + page_size, total)
        page_models = models[start:end]

        buttons: list = []
        for i, model_id in enumerate(page_models):
            abs_idx = start + i
            short = model_id.split("/")[-1] if "/" in model_id else model_id
            if len(short) > 38:
                short = short[:35] + "..."
            buttons.append(
                InlineKeyboardButton(short, callback_data=f"mm:{abs_idx}")
            )

        rows = [buttons[i : i + 2] for i in range(0, len(buttons), 2)]

        # Pagination row (if needed)
        if total_pages > 1:
            nav: list = []
            if page > 0:
                nav.append(InlineKeyboardButton("◀ Prev", callback_data=f"mg:{page - 1}"))
            nav.append(InlineKeyboardButton(f"{page + 1}/{total_pages}", callback_data="mx:noop"))
            if page < total_pages - 1:
                nav.append(InlineKeyboardButton("Next ▶", callback_data=f"mg:{page + 1}"))
            rows.append(nav)

        rows.append([
            InlineKeyboardButton("◀ Back", callback_data="mb"),
            InlineKeyboardButton("✗ Cancel", callback_data="mx"),
        ])

        page_info = f" ({start + 1}–{end} of {total})" if total_pages > 1 else ""
        return InlineKeyboardMarkup(rows), page_info

    async def _handle_model_picker_callback(
        self, query, data: str, chat_id: str
    ) -> None:
        """Handle model picker inline keyboard callbacks (mp:/mm:/mb:/mx:/mg:)."""
        state = self._model_picker_state.get(chat_id)
        if not state:
            await query.answer(text="Picker expired — use /model again.")
            return

        try:
            from hermes_cli.providers import get_label
        except ImportError:
            def get_label(slug):
                return slug

        if data.startswith("mp:"):
            # --- Provider selected: show model buttons (page 0) ---
            provider_slug = data[3:]
            provider = next(
                (p for p in state["providers"] if p["slug"] == provider_slug),
                None,
            )
            if not provider:
                await query.answer(text="Provider not found.")
                return

            models = provider.get("models", [])
            state["selected_provider"] = provider_slug
            state["selected_provider_name"] = provider.get("name", provider_slug)
            state["model_list"] = models
            state["model_page"] = 0

            keyboard, page_info = self._build_model_keyboard(models, 0)

            pname = provider.get("name", provider_slug)
            total = provider.get("total_models", len(models))
            shown = len(models)
            extra = f"\n_{total - shown} more available — type `/model <name>` directly_" if total > shown else ""

            await query.edit_message_text(
                text=(
                    f"⚙ *Model Configuration*\n\n"
                    f"Provider: *{pname}*{page_info}\n"
                    f"Select a model:{extra}"
                ),
                parse_mode=ParseMode.MARKDOWN,
                reply_markup=keyboard,
            )
            await query.answer()

        elif data.startswith("mg:"):
            # --- Page navigation ---
            try:
                page = int(data[3:])
            except ValueError:
                await query.answer(text="Invalid page.")
                return

            models = state.get("model_list", [])
            state["model_page"] = page

            keyboard, page_info = self._build_model_keyboard(models, page)

            pname = state.get("selected_provider_name", "")
            provider_slug = state.get("selected_provider", "")
            provider = next(
                (p for p in state["providers"] if p["slug"] == provider_slug),
                None,
            )
            total = provider.get("total_models", len(models)) if provider else len(models)
            shown = len(models)
            extra = f"\n_{total - shown} more available — type `/model <name>` directly_" if total > shown else ""

            await query.edit_message_text(
                text=(
                    f"⚙ *Model Configuration*\n\n"
                    f"Provider: *{pname}*{page_info}\n"
                    f"Select a model:{extra}"
                ),
                parse_mode=ParseMode.MARKDOWN,
                reply_markup=keyboard,
            )
            await query.answer()

        elif data.startswith("mm:"):
            # --- Model selected: perform the switch ---
            try:
                idx = int(data[3:])
            except ValueError:
                await query.answer(text="Invalid selection.")
                return

            model_list = state.get("model_list", [])
            if idx < 0 or idx >= len(model_list):
                await query.answer(text="Invalid model index.")
                return

            model_id = model_list[idx]
            provider_slug = state.get("selected_provider", "")
            callback = state.get("on_model_selected")

            if not callback:
                await query.answer(text="Picker expired.")
                return

            try:
                result_text = await callback(chat_id, model_id, provider_slug)
            except Exception as exc:
                logger.error("Model picker switch failed: %s", exc)
                result_text = f"Error switching model: {exc}"

            # Edit message to show confirmation, remove buttons
            try:
                await query.edit_message_text(
                    text=result_text,
                    parse_mode=ParseMode.MARKDOWN,
                    reply_markup=None,
                )
            except Exception:
                # Markdown parse failure — retry as plain text
                try:
                    await query.edit_message_text(
                        text=result_text,
                        parse_mode=None,
                        reply_markup=None,
                    )
                except Exception:
                    pass
            await query.answer(text="Model switched!")

            # Clean up state
            self._model_picker_state.pop(chat_id, None)

        elif data == "mb":
            # --- Back to provider list ---
            buttons = []
            for p in state["providers"]:
                count = p.get("total_models", len(p.get("models", [])))
                label = f"{p['name']} ({count})"
                if p.get("is_current"):
                    label = f"✓ {label}"
                buttons.append(
                    InlineKeyboardButton(label, callback_data=f"mp:{p['slug']}")
                )

            rows = [buttons[i : i + 2] for i in range(0, len(buttons), 2)]
            rows.append([InlineKeyboardButton("✗ Cancel", callback_data="mx")])
            keyboard = InlineKeyboardMarkup(rows)

            try:
                provider_label = get_label(state["current_provider"])
            except Exception:
                provider_label = state["current_provider"]

            await query.edit_message_text(
                text=(
                    f"⚙ *Model Configuration*\n\n"
                    f"Current model: `{state['current_model'] or 'unknown'}`\n"
                    f"Provider: {provider_label}\n\n"
                    f"Select a provider:"
                ),
                parse_mode=ParseMode.MARKDOWN,
                reply_markup=keyboard,
            )
            await query.answer()

        elif data == "mx":
            # --- Cancel ---
            self._model_picker_state.pop(chat_id, None)
            await query.edit_message_text(
                text="Model selection cancelled.",
                reply_markup=None,
            )
            await query.answer()

        else:
            # Catch-all (e.g. page counter button "mx:noop")
            await query.answer()

    async def _handle_callback_query(
        self, update: "Update", context: "ContextTypes.DEFAULT_TYPE"
    ) -> None:
        """Handle inline keyboard button clicks."""
        query = update.callback_query
        if not query or not query.data:
            return
        data = query.data

        # --- Model picker callbacks ---
        if data.startswith(("mp:", "mm:", "mb", "mx", "mg:")):
            chat_id = str(query.message.chat_id) if query.message else None
            if chat_id:
                await self._handle_model_picker_callback(query, data, chat_id)
            return

        # --- Exec approval callbacks (ea:choice:id) ---
        if data.startswith("ea:"):
            parts = data.split(":", 2)
            if len(parts) == 3:
                choice = parts[1]  # once, session, always, deny
                try:
                    approval_id = int(parts[2])
                except (ValueError, IndexError):
                    await query.answer(text="Invalid approval data.")
                    return

                # Only authorized users may click approval buttons.
                caller_id = str(getattr(query.from_user, "id", ""))
                allowed_csv = os.getenv("TELEGRAM_ALLOWED_USERS", "").strip()
                if allowed_csv:
                    allowed_ids = {uid.strip() for uid in allowed_csv.split(",") if uid.strip()}
                    if "*" not in allowed_ids and caller_id not in allowed_ids:
                        await query.answer(text="⛔ You are not authorized to approve commands.")
                        return

                session_key = self._approval_state.pop(approval_id, None)
                if not session_key:
                    await query.answer(text="This approval has already been resolved.")
                    return

                # Map choice to human-readable label
                label_map = {
                    "once": "✅ Approved once",
                    "session": "✅ Approved for session",
                    "always": "✅ Approved permanently",
                    "deny": "❌ Denied",
                }
                user_display = getattr(query.from_user, "first_name", "User")
                label = label_map.get(choice, "Resolved")

                await query.answer(text=label)

                # Edit message to show decision, remove buttons
                try:
                    await query.edit_message_text(
                        text=f"{label} by {user_display}",
                        parse_mode=ParseMode.MARKDOWN,
                        reply_markup=None,
                    )
                except Exception:
                    pass  # non-fatal if edit fails

                # Resolve the approval — unblocks the agent thread
                try:
                    from tools.approval import resolve_gateway_approval
                    count = resolve_gateway_approval(session_key, choice)
                    logger.info(
                        "Telegram button resolved %d approval(s) for session %s (choice=%s, user=%s)",
                        count, session_key, choice, user_display,
                    )
                except Exception as exc:
                    logger.error("Failed to resolve gateway approval from Telegram button: %s", exc)
            return

        # --- Update prompt callbacks ---
        if not data.startswith("update_prompt:"):
            return
        answer = data.split(":", 1)[1]  # "y" or "n"
        await query.answer(text=f"Sent '{answer}' to the update process.")
        # Edit the message to show the choice and remove buttons
        label = "Yes" if answer == "y" else "No"
        try:
            await query.edit_message_text(
                text=f"⚕ Update prompt answered: *{label}*",
                parse_mode=ParseMode.MARKDOWN,
                reply_markup=None,
            )
        except Exception:
            pass  # non-fatal if edit fails
        # Write the response file
        try:
            from hermes_constants import get_hermes_home
            home = get_hermes_home()
            response_path = home / ".update_response"
            tmp = response_path.with_suffix(".tmp")
            tmp.write_text(answer)
            tmp.replace(response_path)
            logger.info("Telegram update prompt answered '%s' by user %s",
                        answer, getattr(query.from_user, "id", "unknown"))
        except Exception as exc:
            logger.error("Failed to write update response from callback: %s", exc)

    async def send_voice(
        self,
        chat_id: str,
        audio_path: str,
        caption: Optional[str] = None,
        reply_to: Optional[str] = None,
        metadata: Optional[Dict[str, Any]] = None,
        **kwargs,
    ) -> SendResult:
        """Send audio as a native Telegram voice message or audio file."""
        if not self._bot:
            return SendResult(success=False, error="Not connected")
        
        try:
            import os
            if not os.path.exists(audio_path):
                return SendResult(success=False, error=f"Audio file not found: {audio_path}")
            
            with open(audio_path, "rb") as audio_file:
                # .ogg files -> send as voice (round playable bubble)
                if audio_path.endswith((".ogg", ".opus")):
                    _voice_thread = metadata.get("thread_id") if metadata else None
                    msg = await self._bot.send_voice(
                        chat_id=int(chat_id),
                        voice=audio_file,
                        caption=caption[:1024] if caption else None,
                        reply_to_message_id=int(reply_to) if reply_to else None,
                        message_thread_id=int(_voice_thread) if _voice_thread else None,
                    )
                else:
                    # .mp3 and others -> send as audio file
                    _audio_thread = metadata.get("thread_id") if metadata else None
                    msg = await self._bot.send_audio(
                        chat_id=int(chat_id),
                        audio=audio_file,
                        caption=caption[:1024] if caption else None,
                        reply_to_message_id=int(reply_to) if reply_to else None,
                        message_thread_id=int(_audio_thread) if _audio_thread else None,
                    )
            return SendResult(success=True, message_id=str(msg.message_id))
        except Exception as e:
            logger.error(
                "[%s] Failed to send Telegram voice/audio, falling back to base adapter: %s",
                self.name,
                e,
                exc_info=True,
            )
            return await super().send_voice(chat_id, audio_path, caption, reply_to)
    
    async def send_image_file(
        self,
        chat_id: str,
        image_path: str,
        caption: Optional[str] = None,
        reply_to: Optional[str] = None,
        metadata: Optional[Dict[str, Any]] = None,
        **kwargs,
    ) -> SendResult:
        """Send a local image file natively as a Telegram photo."""
        if not self._bot:
            return SendResult(success=False, error="Not connected")

        try:
            import os
            if not os.path.exists(image_path):
                return SendResult(success=False, error=f"Image file not found: {image_path}")

            _thread = metadata.get("thread_id") if metadata else None
            with open(image_path, "rb") as image_file:
                msg = await self._bot.send_photo(
                    chat_id=int(chat_id),
                    photo=image_file,
                    caption=caption[:1024] if caption else None,
                    reply_to_message_id=int(reply_to) if reply_to else None,
                    message_thread_id=int(_thread) if _thread else None,
                )
            return SendResult(success=True, message_id=str(msg.message_id))
        except Exception as e:
            logger.error(
                "[%s] Failed to send Telegram local image, falling back to base adapter: %s",
                self.name,
                e,
                exc_info=True,
            )
            return await super().send_image_file(chat_id, image_path, caption, reply_to)

    async def send_document(
        self,
        chat_id: str,
        file_path: str,
        caption: Optional[str] = None,
        file_name: Optional[str] = None,
        reply_to: Optional[str] = None,
        metadata: Optional[Dict[str, Any]] = None,
        **kwargs,
    ) -> SendResult:
        """Send a document/file natively as a Telegram file attachment."""
        if not self._bot:
            return SendResult(success=False, error="Not connected")

        try:
            if not os.path.exists(file_path):
                return SendResult(success=False, error=f"File not found: {file_path}")

            display_name = file_name or os.path.basename(file_path)
            _thread = metadata.get("thread_id") if metadata else None

            with open(file_path, "rb") as f:
                msg = await self._bot.send_document(
                    chat_id=int(chat_id),
                    document=f,
                    filename=display_name,
                    caption=caption[:1024] if caption else None,
                    reply_to_message_id=int(reply_to) if reply_to else None,
                    message_thread_id=int(_thread) if _thread else None,
                )
            return SendResult(success=True, message_id=str(msg.message_id))
        except Exception as e:
            print(f"[{self.name}] Failed to send document: {e}")
            return await super().send_document(chat_id, file_path, caption, file_name, reply_to)

    async def send_video(
        self,
        chat_id: str,
        video_path: str,
        caption: Optional[str] = None,
        reply_to: Optional[str] = None,
        metadata: Optional[Dict[str, Any]] = None,
        **kwargs,
    ) -> SendResult:
        """Send a video natively as a Telegram video message."""
        if not self._bot:
            return SendResult(success=False, error="Not connected")

        try:
            if not os.path.exists(video_path):
                return SendResult(success=False, error=f"Video file not found: {video_path}")

            _thread = metadata.get("thread_id") if metadata else None
            with open(video_path, "rb") as f:
                msg = await self._bot.send_video(
                    chat_id=int(chat_id),
                    video=f,
                    caption=caption[:1024] if caption else None,
                    reply_to_message_id=int(reply_to) if reply_to else None,
                    message_thread_id=int(_thread) if _thread else None,
                )
            return SendResult(success=True, message_id=str(msg.message_id))
        except Exception as e:
            print(f"[{self.name}] Failed to send video: {e}")
            return await super().send_video(chat_id, video_path, caption, reply_to)

    async def send_image(
        self,
        chat_id: str,
        image_url: str,
        caption: Optional[str] = None,
        reply_to: Optional[str] = None,
        metadata: Optional[Dict[str, Any]] = None,
    ) -> SendResult:
        """Send an image natively as a Telegram photo.
        
        Tries URL-based send first (fast, works for <5MB images).
        Falls back to downloading and uploading as file (supports up to 10MB).
        """
        if not self._bot:
            return SendResult(success=False, error="Not connected")

        from tools.url_safety import is_safe_url
        if not is_safe_url(image_url):
            logger.warning("[%s] Blocked unsafe image URL (SSRF protection)", self.name)
            return await super().send_image(chat_id, image_url, caption, reply_to, metadata=metadata)

        try:
            # Telegram can send photos directly from URLs (up to ~5MB)
            _photo_thread = metadata.get("thread_id") if metadata else None
            msg = await self._bot.send_photo(
                chat_id=int(chat_id),
                photo=image_url,
                caption=caption[:1024] if caption else None,  # Telegram caption limit
                reply_to_message_id=int(reply_to) if reply_to else None,
                message_thread_id=int(_photo_thread) if _photo_thread else None,
            )
            return SendResult(success=True, message_id=str(msg.message_id))
        except Exception as e:
            logger.warning(
                "[%s] URL-based send_photo failed, trying file upload: %s",
                self.name,
                e,
                exc_info=True,
            )
            # Fallback: download and upload as file (supports up to 10MB)
            try:
                import httpx
                async with httpx.AsyncClient(timeout=30.0) as client:
                    resp = await client.get(image_url)
                    resp.raise_for_status()
                    image_data = resp.content
                
                msg = await self._bot.send_photo(
                    chat_id=int(chat_id),
                    photo=image_data,
                    caption=caption[:1024] if caption else None,
                    reply_to_message_id=int(reply_to) if reply_to else None,
                )
                return SendResult(success=True, message_id=str(msg.message_id))
            except Exception as e2:
                logger.error(
                    "[%s] File upload send_photo also failed: %s",
                    self.name,
                    e2,
                    exc_info=True,
                )
                # Final fallback: send URL as text
                return await super().send_image(chat_id, image_url, caption, reply_to)
    
    async def send_animation(
        self,
        chat_id: str,
        animation_url: str,
        caption: Optional[str] = None,
        reply_to: Optional[str] = None,
        metadata: Optional[Dict[str, Any]] = None,
    ) -> SendResult:
        """Send an animated GIF natively as a Telegram animation (auto-plays inline)."""
        if not self._bot:
            return SendResult(success=False, error="Not connected")
        
        try:
            _anim_thread = metadata.get("thread_id") if metadata else None
            msg = await self._bot.send_animation(
                chat_id=int(chat_id),
                animation=animation_url,
                caption=caption[:1024] if caption else None,
                reply_to_message_id=int(reply_to) if reply_to else None,
                message_thread_id=int(_anim_thread) if _anim_thread else None,
            )
            return SendResult(success=True, message_id=str(msg.message_id))
        except Exception as e:
            logger.error(
                "[%s] Failed to send Telegram animation, falling back to photo: %s",
                self.name,
                e,
                exc_info=True,
            )
            # Fallback: try as a regular photo
            return await self.send_image(chat_id, animation_url, caption, reply_to)

    async def send_typing(self, chat_id: str, metadata: Optional[Dict[str, Any]] = None) -> None:
        """Send typing indicator."""
        if self._bot:
            try:
                _typing_thread = metadata.get("thread_id") if metadata else None
                await self._bot.send_chat_action(
                    chat_id=int(chat_id),
                    action="typing",
                    message_thread_id=int(_typing_thread) if _typing_thread else None,
                )
            except Exception as e:
                # Typing failures are non-fatal; log at debug level only.
                logger.debug(
                    "[%s] Failed to send Telegram typing indicator: %s",
                    self.name,
                    e,
                    exc_info=True,
                )
    
    async def get_chat_info(self, chat_id: str) -> Dict[str, Any]:
        """Get information about a Telegram chat."""
        if not self._bot:
            return {"name": "Unknown", "type": "dm"}
        
        try:
            chat = await self._bot.get_chat(int(chat_id))
            
            chat_type = "dm"
            if chat.type == ChatType.GROUP:
                chat_type = "group"
            elif chat.type == ChatType.SUPERGROUP:
                chat_type = "group"
                if chat.is_forum:
                    chat_type = "forum"
            elif chat.type == ChatType.CHANNEL:
                chat_type = "channel"
            
            return {
                "name": chat.title or chat.full_name or str(chat_id),
                "type": chat_type,
                "username": chat.username,
                "is_forum": getattr(chat, "is_forum", False),
            }
        except Exception as e:
            logger.error(
                "[%s] Failed to get Telegram chat info for %s: %s",
                self.name,
                chat_id,
                e,
                exc_info=True,
            )
            return {"name": str(chat_id), "type": "dm", "error": str(e)}
    
    def format_message(self, content: str) -> str:
        """
        Convert standard markdown to Telegram MarkdownV2 format.

        Protected regions (code blocks, inline code) are extracted first so
        their contents are never modified.  Standard markdown constructs
        (headers, bold, italic, links) are translated to MarkdownV2 syntax,
        and all remaining special characters are escaped.
        """
        if not content:
            return content

        placeholders: dict = {}
        counter = [0]

        def _ph(value: str) -> str:
            """Stash *value* behind a placeholder token that survives escaping."""
            key = f"\x00PH{counter[0]}\x00"
            counter[0] += 1
            placeholders[key] = value
            return key

        text = content

        # 1) Protect fenced code blocks (``` ... ```)
        #    Per MarkdownV2 spec, \ and ` inside pre/code must be escaped.
        def _protect_fenced(m):
            raw = m.group(0)
            # Split off opening ``` (with optional language) and closing ```
            open_end = raw.index('\n') + 1 if '\n' in raw[3:] else 3
            opening = raw[:open_end]
            body_and_close = raw[open_end:]
            body = body_and_close[:-3]
            body = body.replace('\\', '\\\\').replace('`', '\\`')
            return _ph(opening + body + '```')

        text = re.sub(
            r'(```(?:[^\n]*\n)?[\s\S]*?```)',
            _protect_fenced,
            text,
        )

        # 2) Protect inline code (`...`)
        #    Escape \ inside inline code per MarkdownV2 spec.
        text = re.sub(
            r'(`[^`]+`)',
            lambda m: _ph(m.group(0).replace('\\', '\\\\')),
            text,
        )

        # 3) Convert markdown links – escape the display text; inside the URL
        #    only ')' and '\' need escaping per the MarkdownV2 spec.
        def _convert_link(m):
            display = _escape_mdv2(m.group(1))
            url = m.group(2).replace('\\', '\\\\').replace(')', '\\)')
            return _ph(f'[{display}]({url})')

        text = re.sub(r'\[([^\]]+)\]\(([^)]+)\)', _convert_link, text)

        # 4) Convert markdown headers (## Title) → bold *Title*
        def _convert_header(m):
            inner = m.group(1).strip()
            # Strip redundant bold markers that may appear inside a header
            inner = re.sub(r'\*\*(.+?)\*\*', r'\1', inner)
            return _ph(f'*{_escape_mdv2(inner)}*')

        text = re.sub(
            r'^#{1,6}\s+(.+)$', _convert_header, text, flags=re.MULTILINE
        )

        # 5) Convert bold: **text** → *text* (MarkdownV2 bold)
        text = re.sub(
            r'\*\*(.+?)\*\*',
            lambda m: _ph(f'*{_escape_mdv2(m.group(1))}*'),
            text,
        )

        # 6) Convert italic: *text* (single asterisk) → _text_ (MarkdownV2 italic)
        #    [^*\n]+ prevents matching across newlines (which would corrupt
        #    bullet lists using * markers and multi-line content).
        text = re.sub(
            r'\*([^*\n]+)\*',
            lambda m: _ph(f'_{_escape_mdv2(m.group(1))}_'),
            text,
        )

        # 7) Convert strikethrough: ~~text~~ → ~text~ (MarkdownV2)
        text = re.sub(
            r'~~(.+?)~~',
            lambda m: _ph(f'~{_escape_mdv2(m.group(1))}~'),
            text,
        )

        # 8) Convert spoiler: ||text|| → ||text|| (protect from | escaping)
        text = re.sub(
            r'\|\|(.+?)\|\|',
            lambda m: _ph(f'||{_escape_mdv2(m.group(1))}||'),
            text,
        )

        # 9) Convert blockquotes: > at line start → protect > from escaping
        #    Handle both regular blockquotes (> text) and expandable blockquotes
        #    (Telegram MarkdownV2: **> for expandable start, || to end the quote)
        def _convert_blockquote(m):
            prefix = m.group(1)  # >, >>, >>>, **>, or **>> etc.
            content = m.group(2)
            # Check if content ends with || (expandable blockquote end marker)
            # In this case, preserve the trailing || unescaped for Telegram
            if prefix.startswith('**') and content.endswith('||'):
                return _ph(f'{prefix} {_escape_mdv2(content[:-2])}||')
            return _ph(f'{prefix} {_escape_mdv2(content)}')

        text = re.sub(
            r'^((?:\*\*)?>{1,3}) (.+)$',
            _convert_blockquote,
            text,
            flags=re.MULTILINE,
        )

        # 10) Escape remaining special characters in plain text
        text = _escape_mdv2(text)

        # 11) Restore placeholders in reverse insertion order so that
        #    nested references (a placeholder inside another) resolve correctly.
        for key in reversed(list(placeholders.keys())):
            text = text.replace(key, placeholders[key])

        # 12) Safety net: escape unescaped ( ) { } that slipped through
        #     placeholder processing.  Split the text into code/non-code
        #     segments so we never touch content inside ``` or ` spans.
        _code_split = re.split(r'(```[\s\S]*?```|`[^`]+`)', text)
        _safe_parts = []
        for _idx, _seg in enumerate(_code_split):
            if _idx % 2 == 1:
                # Inside code span/block — leave untouched
                _safe_parts.append(_seg)
            else:
                # Outside code — escape bare ( ) { }
                def _esc_bare(m, _seg=_seg):
                    s = m.start()
                    ch = m.group(0)
                    # Already escaped
                    if s > 0 and _seg[s - 1] == '\\':
                        return ch
                    # ( that opens a MarkdownV2 link [text](url)
                    if ch == '(' and s > 0 and _seg[s - 1] == ']':
                        return ch
                    # ) that closes a link URL
                    if ch == ')':
                        before = _seg[:s]
                        if '](http' in before or '](' in before:
                            # Check depth
                            depth = 0
                            for j in range(s - 1, max(s - 2000, -1), -1):
                                if _seg[j] == '(':
                                    depth -= 1
                                    if depth < 0:
                                        if j > 0 and _seg[j - 1] == ']':
                                            return ch
                                        break
                                elif _seg[j] == ')':
                                    depth += 1
                    return '\\' + ch
                _safe_parts.append(re.sub(r'[(){}]', _esc_bare, _seg))
        text = ''.join(_safe_parts)

        return text
    
    # ── Group mention gating ──────────────────────────────────────────────

    def _telegram_require_mention(self) -> bool:
        """Return whether group chats should require an explicit bot trigger."""
        configured = self.config.extra.get("require_mention")
        if configured is not None:
            if isinstance(configured, str):
                return configured.lower() in ("true", "1", "yes", "on")
            return bool(configured)
        return os.getenv("TELEGRAM_REQUIRE_MENTION", "false").lower() in ("true", "1", "yes", "on")

    def _telegram_free_response_chats(self) -> set[str]:
        raw = self.config.extra.get("free_response_chats")
        if raw is None:
            raw = os.getenv("TELEGRAM_FREE_RESPONSE_CHATS", "")
        if isinstance(raw, list):
            return {str(part).strip() for part in raw if str(part).strip()}
        return {part.strip() for part in str(raw).split(",") if part.strip()}

    def _telegram_ignored_threads(self) -> set[int]:
        raw = self.config.extra.get("ignored_threads")
        if raw is None:
            raw = os.getenv("TELEGRAM_IGNORED_THREADS", "")

        if isinstance(raw, list):
            values = raw
        else:
            values = str(raw).split(",")

        ignored: set[int] = set()
        for value in values:
            text = str(value).strip()
            if not text:
                continue
            try:
                ignored.add(int(text))
            except (TypeError, ValueError):
                logger.warning("[%s] Ignoring invalid Telegram thread id: %r", self.name, value)
        return ignored

    def _compile_mention_patterns(self) -> List[re.Pattern]:
        """Compile optional regex wake-word patterns for group triggers."""
        patterns = self.config.extra.get("mention_patterns")
        if patterns is None:
            raw = os.getenv("TELEGRAM_MENTION_PATTERNS", "").strip()
            if raw:
                try:
                    loaded = json.loads(raw)
                except Exception:
                    loaded = [part.strip() for part in raw.splitlines() if part.strip()]
                    if not loaded:
                        loaded = [part.strip() for part in raw.split(",") if part.strip()]
                patterns = loaded

        if patterns is None:
            return []
        if isinstance(patterns, str):
            patterns = [patterns]
        if not isinstance(patterns, list):
            logger.warning(
                "[%s] telegram mention_patterns must be a list or string; got %s",
                self.name,
                type(patterns).__name__,
            )
            return []

        compiled: List[re.Pattern] = []
        for pattern in patterns:
            if not isinstance(pattern, str) or not pattern.strip():
                continue
            try:
                compiled.append(re.compile(pattern, re.IGNORECASE))
            except re.error as exc:
                logger.warning("[%s] Invalid Telegram mention pattern %r: %s", self.name, pattern, exc)
        if compiled:
            logger.info("[%s] Loaded %d Telegram mention pattern(s)", self.name, len(compiled))
        return compiled

    def _is_group_chat(self, message: Message) -> bool:
        chat = getattr(message, "chat", None)
        if not chat:
            return False
        chat_type = str(getattr(chat, "type", "")).split(".")[-1].lower()
        return chat_type in ("group", "supergroup")

    def _is_reply_to_bot(self, message: Message) -> bool:
        if not self._bot or not getattr(message, "reply_to_message", None):
            return False
        reply_user = getattr(message.reply_to_message, "from_user", None)
        return bool(reply_user and getattr(reply_user, "id", None) == getattr(self._bot, "id", None))

    def _message_mentions_bot(self, message: Message) -> bool:
        if not self._bot:
            return False

        bot_username = (getattr(self._bot, "username", None) or "").lstrip("@").lower()
        bot_id = getattr(self._bot, "id", None)

        def _iter_sources():
            yield getattr(message, "text", None) or "", getattr(message, "entities", None) or []
            yield getattr(message, "caption", None) or "", getattr(message, "caption_entities", None) or []

        for source_text, entities in _iter_sources():
            if bot_username and f"@{bot_username}" in source_text.lower():
                return True
            for entity in entities:
                entity_type = str(getattr(entity, "type", "")).split(".")[-1].lower()
                if entity_type == "mention" and bot_username:
                    offset = int(getattr(entity, "offset", -1))
                    length = int(getattr(entity, "length", 0))
                    if offset < 0 or length <= 0:
                        continue
                    if source_text[offset:offset + length].strip().lower() == f"@{bot_username}":
                        return True
                elif entity_type == "text_mention":
                    user = getattr(entity, "user", None)
                    if user and getattr(user, "id", None) == bot_id:
                        return True
        return False

    def _message_matches_mention_patterns(self, message: Message) -> bool:
        if not self._mention_patterns:
            return False
        for candidate in (getattr(message, "text", None), getattr(message, "caption", None)):
            if not candidate:
                continue
            for pattern in self._mention_patterns:
                if pattern.search(candidate):
                    return True
        return False

    def _clean_bot_trigger_text(self, text: Optional[str]) -> Optional[str]:
        if not text or not self._bot or not getattr(self._bot, "username", None):
            return text
        username = re.escape(self._bot.username)
        cleaned = re.sub(rf"(?i)@{username}\b[,:\-]*\s*", "", text).strip()
        return cleaned or text

    def _should_process_message(self, message: Message, *, is_command: bool = False) -> bool:
        """Apply Telegram group trigger rules.

        DMs remain unrestricted. Group/supergroup messages are accepted when:
        - the chat is explicitly allowlisted in ``free_response_chats``
        - ``require_mention`` is disabled
        - the message is a command
        - the message replies to the bot
        - the bot is @mentioned
        - the text/caption matches a configured regex wake-word pattern
        """
        if not self._is_group_chat(message):
            return True
        thread_id = getattr(message, "message_thread_id", None)
        if thread_id is not None:
            try:
                if int(thread_id) in self._telegram_ignored_threads():
                    return False
            except (TypeError, ValueError):
                logger.warning("[%s] Ignoring non-numeric Telegram message_thread_id: %r", self.name, thread_id)
        if str(getattr(getattr(message, "chat", None), "id", "")) in self._telegram_free_response_chats():
            return True
        if not self._telegram_require_mention():
            return True
        if is_command:
            return True
        if self._is_reply_to_bot(message):
            return True
        if self._message_mentions_bot(message):
            return True
        return self._message_matches_mention_patterns(message)

    async def _handle_text_message(self, update: Update, context: ContextTypes.DEFAULT_TYPE) -> None:
        """Handle incoming text messages.

        Telegram clients split long messages into multiple updates.  Buffer
        rapid successive text messages from the same user/chat and aggregate
        them into a single MessageEvent before dispatching.
        """
        if not update.message or not update.message.text:
            return
        if not self._should_process_message(update.message):
            return

        event = self._build_message_event(update.message, MessageType.TEXT)
        event.text = self._clean_bot_trigger_text(event.text)
        self._enqueue_text_event(event)
    
    async def _handle_command(self, update: Update, context: ContextTypes.DEFAULT_TYPE) -> None:
        """Handle incoming command messages."""
        if not update.message or not update.message.text:
            return
        if not self._should_process_message(update.message, is_command=True):
            return
        
        event = self._build_message_event(update.message, MessageType.COMMAND)
        await self.handle_message(event)
    
    async def _handle_location_message(self, update: Update, context: ContextTypes.DEFAULT_TYPE) -> None:
        """Handle incoming location/venue pin messages."""
        if not update.message:
            return
        if not self._should_process_message(update.message):
            return

        msg = update.message
        venue = getattr(msg, "venue", None)
        location = getattr(venue, "location", None) if venue else getattr(msg, "location", None)

        if not location:
            return

        lat = getattr(location, "latitude", None)
        lon = getattr(location, "longitude", None)
        if lat is None or lon is None:
            return

        # Build a text message with coordinates and context
        parts = ["[The user shared a location pin.]"]
        if venue:
            title = getattr(venue, "title", None)
            address = getattr(venue, "address", None)
            if title:
                parts.append(f"Venue: {title}")
            if address:
                parts.append(f"Address: {address}")
        parts.append(f"latitude: {lat}")
        parts.append(f"longitude: {lon}")
        parts.append(f"Map: https://www.google.com/maps/search/?api=1&query={lat},{lon}")
        parts.append("Ask what they'd like to find nearby (restaurants, cafes, etc.) and any preferences.")

        event = self._build_message_event(msg, MessageType.LOCATION)
        event.text = "\n".join(parts)
        await self.handle_message(event)

    # ------------------------------------------------------------------
    # Text message aggregation (handles Telegram client-side splits)
    # ------------------------------------------------------------------

    def _text_batch_key(self, event: MessageEvent) -> str:
        """Session-scoped key for text message batching."""
        from gateway.session import build_session_key
        return build_session_key(
            event.source,
            group_sessions_per_user=self.config.extra.get("group_sessions_per_user", True),
            thread_sessions_per_user=self.config.extra.get("thread_sessions_per_user", False),
        )

    def _enqueue_text_event(self, event: MessageEvent) -> None:
        """Buffer a text event and reset the flush timer.

        When Telegram splits a long user message into multiple updates,
        they arrive within a few hundred milliseconds.  This method
        concatenates them and waits for a short quiet period before
        dispatching the combined message.
        """
        key = self._text_batch_key(event)
        existing = self._pending_text_batches.get(key)
        chunk_len = len(event.text or "")
        if existing is None:
            event._last_chunk_len = chunk_len  # type: ignore[attr-defined]
            self._pending_text_batches[key] = event
        else:
            # Append text from the follow-up chunk
            if event.text:
                existing.text = f"{existing.text}\n{event.text}" if existing.text else event.text
            existing._last_chunk_len = chunk_len  # type: ignore[attr-defined]
            # Merge any media that might be attached
            if event.media_urls:
                existing.media_urls.extend(event.media_urls)
                existing.media_types.extend(event.media_types)

        # Cancel any pending flush and restart the timer
        prior_task = self._pending_text_batch_tasks.get(key)
        if prior_task and not prior_task.done():
            prior_task.cancel()
        self._pending_text_batch_tasks[key] = asyncio.create_task(
            self._flush_text_batch(key)
        )

    async def _flush_text_batch(self, key: str) -> None:
        """Wait for the quiet period then dispatch the aggregated text.

        Uses a longer delay when the latest chunk is near Telegram's 4096-char
        split point, since a continuation chunk is almost certain.
        """
        current_task = asyncio.current_task()
        try:
            # Adaptive delay: if the latest chunk is near Telegram's 4096-char
            # split point, a continuation is almost certain — wait longer.
            pending = self._pending_text_batches.get(key)
            last_len = getattr(pending, "_last_chunk_len", 0) if pending else 0
            if last_len >= self._SPLIT_THRESHOLD:
                delay = self._text_batch_split_delay_seconds
            else:
                delay = self._text_batch_delay_seconds
            await asyncio.sleep(delay)
            event = self._pending_text_batches.pop(key, None)
            if not event:
                return
            logger.info(
                "[Telegram] Flushing text batch %s (%d chars)",
                key, len(event.text or ""),
            )
            await self.handle_message(event)
        finally:
            if self._pending_text_batch_tasks.get(key) is current_task:
                self._pending_text_batch_tasks.pop(key, None)

    # ------------------------------------------------------------------
    # Photo batching
    # ------------------------------------------------------------------

    def _photo_batch_key(self, event: MessageEvent, msg: Message) -> str:
        """Return a batching key for Telegram photos/albums."""
        from gateway.session import build_session_key
        session_key = build_session_key(
            event.source,
            group_sessions_per_user=self.config.extra.get("group_sessions_per_user", True),
            thread_sessions_per_user=self.config.extra.get("thread_sessions_per_user", False),
        )
        media_group_id = getattr(msg, "media_group_id", None)
        if media_group_id:
            return f"{session_key}:album:{media_group_id}"
        return f"{session_key}:photo-burst"

    async def _flush_photo_batch(self, batch_key: str) -> None:
        """Send a buffered photo burst/album as a single MessageEvent."""
        current_task = asyncio.current_task()
        try:
            await asyncio.sleep(self._media_batch_delay_seconds)
            event = self._pending_photo_batches.pop(batch_key, None)
            if not event:
                return
            logger.info("[Telegram] Flushing photo batch %s with %d image(s)", batch_key, len(event.media_urls))
            await self.handle_message(event)
        finally:
            if self._pending_photo_batch_tasks.get(batch_key) is current_task:
                self._pending_photo_batch_tasks.pop(batch_key, None)

    def _enqueue_photo_event(self, batch_key: str, event: MessageEvent) -> None:
        """Merge photo events into a pending batch and schedule flush."""
        existing = self._pending_photo_batches.get(batch_key)
        if existing is None:
            self._pending_photo_batches[batch_key] = event
        else:
            existing.media_urls.extend(event.media_urls)
            existing.media_types.extend(event.media_types)
            if event.text:
                existing.text = self._merge_caption(existing.text, event.text)

        prior_task = self._pending_photo_batch_tasks.get(batch_key)
        if prior_task and not prior_task.done():
            prior_task.cancel()

        self._pending_photo_batch_tasks[batch_key] = asyncio.create_task(self._flush_photo_batch(batch_key))

    async def _handle_media_message(self, update: Update, context: ContextTypes.DEFAULT_TYPE) -> None:
        """Handle incoming media messages, downloading images to local cache."""
        if not update.message:
            return
        if not self._should_process_message(update.message):
            return
        
        msg = update.message
        
        # Determine media type
        if msg.sticker:
            msg_type = MessageType.STICKER
        elif msg.photo:
            msg_type = MessageType.PHOTO
        elif msg.video:
            msg_type = MessageType.VIDEO
        elif msg.audio:
            msg_type = MessageType.AUDIO
        elif msg.voice:
            msg_type = MessageType.VOICE
        elif msg.document:
            msg_type = MessageType.DOCUMENT
        else:
            msg_type = MessageType.DOCUMENT
        
        event = self._build_message_event(msg, msg_type)
        
        # Add caption as text
        if msg.caption:
            event.text = self._clean_bot_trigger_text(msg.caption)
        
        # Handle stickers: describe via vision tool with caching
        if msg.sticker:
            await self._handle_sticker(msg, event)
            await self.handle_message(event)
            return
        
        # Download photo to local image cache so the vision tool can access it
        # even after Telegram's ephemeral file URLs expire (~1 hour).
        if msg.photo:
            try:
                # msg.photo is a list of PhotoSize sorted by size; take the largest
                photo = msg.photo[-1]
                file_obj = await photo.get_file()
                # Download the image bytes directly into memory
                image_bytes = await file_obj.download_as_bytearray()
                # Determine extension from the file path if available
                ext = ".jpg"
                if file_obj.file_path:
                    for candidate in [".png", ".webp", ".gif", ".jpeg", ".jpg"]:
                        if file_obj.file_path.lower().endswith(candidate):
                            ext = candidate
                            break
                # Save to local cache (for vision tool access)
                cached_path = cache_image_from_bytes(bytes(image_bytes), ext=ext)
                event.media_urls = [cached_path]
                event.media_types = [f"image/{ext.lstrip('.')}" ]
                logger.info("[Telegram] Cached user photo at %s", cached_path)
                media_group_id = getattr(msg, "media_group_id", None)
                if media_group_id:
                    await self._queue_media_group_event(str(media_group_id), event)
                else:
                    batch_key = self._photo_batch_key(event, msg)
                    self._enqueue_photo_event(batch_key, event)
                return

            except Exception as e:
                logger.warning("[Telegram] Failed to cache photo: %s", e, exc_info=True)

        # Download voice/audio messages to cache for STT transcription
        if msg.voice:
            try:
                file_obj = await msg.voice.get_file()
                audio_bytes = await file_obj.download_as_bytearray()
                cached_path = cache_audio_from_bytes(bytes(audio_bytes), ext=".ogg")
                event.media_urls = [cached_path]
                event.media_types = ["audio/ogg"]
                logger.info("[Telegram] Cached user voice at %s", cached_path)
            except Exception as e:
                logger.warning("[Telegram] Failed to cache voice: %s", e, exc_info=True)
        elif msg.audio:
            try:
                file_obj = await msg.audio.get_file()
                audio_bytes = await file_obj.download_as_bytearray()
                cached_path = cache_audio_from_bytes(bytes(audio_bytes), ext=".mp3")
                event.media_urls = [cached_path]
                event.media_types = ["audio/mp3"]
                logger.info("[Telegram] Cached user audio at %s", cached_path)
            except Exception as e:
                logger.warning("[Telegram] Failed to cache audio: %s", e, exc_info=True)

        # Download document files to cache for agent processing
        elif msg.document:
            doc = msg.document
            try:
                # Determine file extension
                ext = ""
                original_filename = doc.file_name or ""
                if original_filename:
                    _, ext = os.path.splitext(original_filename)
                    ext = ext.lower()

                # If no extension from filename, reverse-lookup from MIME type
                if not ext and doc.mime_type:
                    mime_to_ext = {v: k for k, v in SUPPORTED_DOCUMENT_TYPES.items()}
                    ext = mime_to_ext.get(doc.mime_type, "")

                # Check if supported
                if ext not in SUPPORTED_DOCUMENT_TYPES:
                    supported_list = ", ".join(sorted(SUPPORTED_DOCUMENT_TYPES.keys()))
                    event.text = (
                        f"Unsupported document type '{ext or 'unknown'}'. "
                        f"Supported types: {supported_list}"
                    )
                    logger.info("[Telegram] Unsupported document type: %s", ext or "unknown")
                    await self.handle_message(event)
                    return

                # Check file size (Telegram Bot API limit: 20 MB)
                MAX_DOC_BYTES = 20 * 1024 * 1024
                if not doc.file_size or doc.file_size > MAX_DOC_BYTES:
                    event.text = (
                        "The document is too large or its size could not be verified. "
                        "Maximum: 20 MB."
                    )
                    logger.info("[Telegram] Document too large: %s bytes", doc.file_size)
                    await self.handle_message(event)
                    return

                # Download and cache
                file_obj = await doc.get_file()
                doc_bytes = await file_obj.download_as_bytearray()
                raw_bytes = bytes(doc_bytes)
                cached_path = cache_document_from_bytes(raw_bytes, original_filename or f"document{ext}")
                mime_type = SUPPORTED_DOCUMENT_TYPES[ext]
                event.media_urls = [cached_path]
                event.media_types = [mime_type]
                logger.info("[Telegram] Cached user document at %s", cached_path)

                # For text files, inject content into event.text (capped at 100 KB)
                MAX_TEXT_INJECT_BYTES = 100 * 1024
                if ext in (".md", ".txt") and len(raw_bytes) <= MAX_TEXT_INJECT_BYTES:
                    try:
                        text_content = raw_bytes.decode("utf-8")
                        display_name = original_filename or f"document{ext}"
                        display_name = re.sub(r'[^\w.\- ]', '_', display_name)
                        injection = f"[Content of {display_name}]:\n{text_content}"
                        if event.text:
                            event.text = f"{injection}\n\n{event.text}"
                        else:
                            event.text = injection
                    except UnicodeDecodeError:
                        logger.warning(
                            "[Telegram] Could not decode text file as UTF-8, skipping content injection",
                            exc_info=True,
                        )

            except Exception as e:
                logger.warning("[Telegram] Failed to cache document: %s", e, exc_info=True)

        media_group_id = getattr(msg, "media_group_id", None)
        if media_group_id:
            await self._queue_media_group_event(str(media_group_id), event)
            return

        await self.handle_message(event)
    
    async def _queue_media_group_event(self, media_group_id: str, event: MessageEvent) -> None:
        """Buffer Telegram media-group items so albums arrive as one logical event.

        Telegram delivers albums as multiple updates with a shared media_group_id.
        If we forward each item immediately, the gateway thinks the second image is a
        new user message and interrupts the first. We debounce briefly and merge the
        attachments into a single MessageEvent.
        """
        existing = self._media_group_events.get(media_group_id)
        if existing is None:
            self._media_group_events[media_group_id] = event
        else:
            existing.media_urls.extend(event.media_urls)
            existing.media_types.extend(event.media_types)
            if event.text:
                existing.text = self._merge_caption(existing.text, event.text)

        prior_task = self._media_group_tasks.get(media_group_id)
        if prior_task:
            prior_task.cancel()

        self._media_group_tasks[media_group_id] = asyncio.create_task(
            self._flush_media_group_event(media_group_id)
        )

    async def _flush_media_group_event(self, media_group_id: str) -> None:
        try:
            await asyncio.sleep(self.MEDIA_GROUP_WAIT_SECONDS)
            event = self._media_group_events.pop(media_group_id, None)
            if event is not None:
                await self.handle_message(event)
        except asyncio.CancelledError:
            return
        finally:
            self._media_group_tasks.pop(media_group_id, None)

    async def _handle_sticker(self, msg: Message, event: "MessageEvent") -> None:
        """
        Describe a Telegram sticker via vision analysis, with caching.

        For static stickers (WEBP), we download, analyze with vision, and cache
        the description by file_unique_id. For animated/video stickers, we inject
        a placeholder noting the emoji.
        """
        from gateway.sticker_cache import (
            get_cached_description,
            cache_sticker_description,
            build_sticker_injection,
            build_animated_sticker_injection,
            STICKER_VISION_PROMPT,
        )

        sticker = msg.sticker
        emoji = sticker.emoji or ""
        set_name = sticker.set_name or ""

        # Animated and video stickers can't be analyzed as static images
        if sticker.is_animated or sticker.is_video:
            event.text = build_animated_sticker_injection(emoji)
            return

        # Check the cache first
        cached = get_cached_description(sticker.file_unique_id)
        if cached:
            event.text = build_sticker_injection(
                cached["description"], cached.get("emoji", emoji), cached.get("set_name", set_name)
            )
            logger.info("[Telegram] Sticker cache hit: %s", sticker.file_unique_id)
            return

        # Cache miss -- download and analyze
        try:
            file_obj = await sticker.get_file()
            image_bytes = await file_obj.download_as_bytearray()
            cached_path = cache_image_from_bytes(bytes(image_bytes), ext=".webp")
            logger.info("[Telegram] Analyzing sticker at %s", cached_path)

            from tools.vision_tools import vision_analyze_tool
            import json as _json

            result_json = await vision_analyze_tool(
                image_url=cached_path,
                user_prompt=STICKER_VISION_PROMPT,
            )
            result = _json.loads(result_json)

            if result.get("success"):
                description = result.get("analysis", "a sticker")
                cache_sticker_description(sticker.file_unique_id, description, emoji, set_name)
                event.text = build_sticker_injection(description, emoji, set_name)
            else:
                # Vision failed -- use emoji as fallback
                event.text = build_sticker_injection(
                    f"a sticker with emoji {emoji}" if emoji else "a sticker",
                    emoji, set_name,
                )
        except Exception as e:
            logger.warning("[Telegram] Sticker analysis error: %s", e, exc_info=True)
            event.text = build_sticker_injection(
                f"a sticker with emoji {emoji}" if emoji else "a sticker",
                emoji, set_name,
            )

    def _reload_dm_topics_from_config(self) -> None:
        """Re-read dm_topics from config.yaml and load any new thread_ids into cache.

        This allows topics created externally (e.g. by the agent via API) to be
        recognized without a gateway restart.
        """
        try:
            from hermes_constants import get_hermes_home
            config_path = get_hermes_home() / "config.yaml"
            if not config_path.exists():
                return

            import yaml as _yaml
            with open(config_path, "r") as f:
                config = _yaml.safe_load(f) or {}

            dm_topics = (
                config.get("platforms", {})
                .get("telegram", {})
                .get("extra", {})
                .get("dm_topics", [])
            )
            if not dm_topics:
                return

            # Update in-memory config and cache any new thread_ids
            self._dm_topics_config = dm_topics
            for chat_entry in dm_topics:
                cid = chat_entry.get("chat_id")
                if not cid:
                    continue
                for t in chat_entry.get("topics", []):
                    tid = t.get("thread_id")
                    name = t.get("name")
                    if tid and name:
                        cache_key = f"{cid}:{name}"
                        if cache_key not in self._dm_topics:
                            self._dm_topics[cache_key] = int(tid)
                            logger.info(
                                "[%s] Hot-loaded DM topic from config: %s -> thread_id=%s",
                                self.name, cache_key, tid,
                            )
        except Exception as e:
            logger.debug("[%s] Failed to reload dm_topics from config: %s", self.name, e)

    def _get_dm_topic_info(self, chat_id: str, thread_id: Optional[str]) -> Optional[Dict[str, Any]]:
        """Look up DM topic config by chat_id and thread_id.

        Returns the topic config dict (name, skill, etc.) if this thread_id
        matches a known DM topic, or None.
        """
        if not thread_id:
            return None

        thread_id_int = int(thread_id)

        # Check cached topics first (created by us or loaded at startup)
        for key, cached_tid in self._dm_topics.items():
            if cached_tid == thread_id_int and key.startswith(f"{chat_id}:"):
                topic_name = key.split(":", 1)[1]
                # Find the full config for this topic
                for chat_entry in self._dm_topics_config:
                    if str(chat_entry.get("chat_id")) == chat_id:
                        for t in chat_entry.get("topics", []):
                            if t.get("name") == topic_name:
                                return t
                return {"name": topic_name}

        # Not in cache — hot-reload config in case topics were added externally
        self._reload_dm_topics_from_config()

        # Check cache again after reload
        for key, cached_tid in self._dm_topics.items():
            if cached_tid == thread_id_int and key.startswith(f"{chat_id}:"):
                topic_name = key.split(":", 1)[1]
                for chat_entry in self._dm_topics_config:
                    if str(chat_entry.get("chat_id")) == chat_id:
                        for t in chat_entry.get("topics", []):
                            if t.get("name") == topic_name:
                                return t
                return {"name": topic_name}

        return None

    def _cache_dm_topic_from_message(self, chat_id: str, thread_id: str, topic_name: str) -> None:
        """Cache a thread_id -> topic_name mapping discovered from an incoming message."""
        cache_key = f"{chat_id}:{topic_name}"
        if cache_key not in self._dm_topics:
            self._dm_topics[cache_key] = int(thread_id)
            logger.info(
                "[%s] Cached DM topic from message: %s -> thread_id=%s",
                self.name, cache_key, thread_id,
            )

    def _build_message_event(self, message: Message, msg_type: MessageType) -> MessageEvent:
        """Build a MessageEvent from a Telegram message."""
        chat = message.chat
        user = message.from_user
        
        # Determine chat type
        chat_type = "dm"
        if chat.type in (ChatType.GROUP, ChatType.SUPERGROUP):
            chat_type = "group"
        elif chat.type == ChatType.CHANNEL:
            chat_type = "channel"

        # Resolve DM topic name and skill binding
        thread_id_raw = message.message_thread_id
        thread_id_str = str(thread_id_raw) if thread_id_raw else None
        chat_topic = None
        topic_skill = None

        if chat_type == "dm" and thread_id_str:
            topic_info = self._get_dm_topic_info(str(chat.id), thread_id_str)
            if topic_info:
                chat_topic = topic_info.get("name")
                topic_skill = topic_info.get("skill")

            # Also check forum_topic_created service message for topic discovery
            if hasattr(message, "forum_topic_created") and message.forum_topic_created:
                created_name = message.forum_topic_created.name
                if created_name:
                    self._cache_dm_topic_from_message(str(chat.id), thread_id_str, created_name)
                    if not chat_topic:
                        chat_topic = created_name

        elif chat_type == "group" and thread_id_str:
            # Group/supergroup forum topic skill binding via config.extra['group_topics']
            group_topics_config: list = self.config.extra.get("group_topics", [])
            for chat_entry in group_topics_config:
                if str(chat_entry.get("chat_id", "")) == str(chat.id):
                    for topic in chat_entry.get("topics", []):
                        tid = topic.get("thread_id")
                        if tid is not None and str(tid) == thread_id_str:
                            chat_topic = topic.get("name")
                            topic_skill = topic.get("skill")
                            break
                    break

        # Build source
        source = self.build_source(
            chat_id=str(chat.id),
            chat_name=chat.title or (chat.full_name if hasattr(chat, "full_name") else None),
            chat_type=chat_type,
            user_id=str(user.id) if user else None,
            user_name=user.full_name if user else None,
            thread_id=thread_id_str,
            chat_topic=chat_topic,
        )
        
        # Extract reply context if this message is a reply
        reply_to_id = None
        reply_to_text = None
        if message.reply_to_message:
            reply_to_id = str(message.reply_to_message.message_id)
            reply_to_text = message.reply_to_message.text or message.reply_to_message.caption or None

        return MessageEvent(
            text=message.text or "",
            message_type=msg_type,
            source=source,
            raw_message=message,
            message_id=str(message.message_id),
            reply_to_message_id=reply_to_id,
            reply_to_text=reply_to_text,
            auto_skill=topic_skill,
            timestamp=message.date,
        )

    # ── Message reactions (processing lifecycle) ──────────────────────────

    def _reactions_enabled(self) -> bool:
        """Check if message reactions are enabled via config/env."""
        return os.getenv("TELEGRAM_REACTIONS", "false").lower() not in ("false", "0", "no")

    async def _set_reaction(self, chat_id: str, message_id: str, emoji: str) -> bool:
        """Set a single emoji reaction on a Telegram message."""
        if not self._bot:
            return False
        try:
            await self._bot.set_message_reaction(
                chat_id=int(chat_id),
                message_id=int(message_id),
                reaction=emoji,
            )
            return True
        except Exception as e:
            logger.debug("[%s] set_message_reaction failed (%s): %s", self.name, emoji, e)
            return False

    async def on_processing_start(self, event: MessageEvent) -> None:
        """Add an in-progress reaction when message processing begins."""
        if not self._reactions_enabled():
            return
        chat_id = getattr(event.source, "chat_id", None)
        message_id = getattr(event, "message_id", None)
        if chat_id and message_id:
            await self._set_reaction(chat_id, message_id, "\U0001f440")

    async def on_processing_complete(self, event: MessageEvent, outcome: ProcessingOutcome) -> None:
        """Swap the in-progress reaction for a final success/failure reaction.

        Unlike Discord (additive reactions), Telegram's set_message_reaction
        replaces all existing reactions in one call — no remove step needed.
        """
        if not self._reactions_enabled():
            return
        chat_id = getattr(event.source, "chat_id", None)
        message_id = getattr(event, "message_id", None)
        if chat_id and message_id and outcome != ProcessingOutcome.CANCELLED:
            await self._set_reaction(
                chat_id,
                message_id,
                "\U0001f44d" if outcome == ProcessingOutcome.SUCCESS else "\U0001f44e",
            )
