main.py

# main.py (Corrected SyntaxError at line 424 - Now with Gemini 2.0 as primary)
import os
import re
import logging
import asyncio
import json
import html
import contextlib
import traceback
from typing import Optional, Dict, Any, Tuple

# --- Frameworks ---
from starlette.applications import Starlette
from starlette.routing import Route
from starlette.responses import PlainTextResponse, JSONResponse, Response
from starlette.requests import Request

# --- Telegram Bot ---
from telegram import Update, InlineKeyboardButton, InlineKeyboardMarkup, Bot
from telegram.ext import (
    Application,
    CommandHandler,
    MessageHandler,
    filters,
    ContextTypes,
    CallbackQueryHandler,
)
from telegram.constants import ParseMode
from telegram.error import NetworkError, RetryAfter, TimedOut, BadRequest, TelegramError
from telegram.request import HTTPXRequest, BaseRequest

# --- Other Libraries ---
import httpx
from youtube_transcript_api import YouTubeTranscriptApi, TranscriptsDisabled, NoTranscriptFound
from bs4 import BeautifulSoup
from tenacity import retry, stop_after_attempt, wait_exponential, retry_if_exception_type, before_sleep_log
try:
    import lxml
    DEFAULT_PARSER = 'lxml'
except ImportError:
    DEFAULT_PARSER = 'html.parser'

# --- Google Gemini ---
try:
    import google.generativeai as genai
    from google.generativeai.types import HarmCategory, HarmBlockThreshold
    _gemini_available = True
except ImportError:
    genai = None
    HarmCategory = None
    HarmBlockThreshold = None
    _gemini_available = False
    # logger will be defined later, log warning after logger setup


# --- Logging Setup ---
logging.basicConfig( format='%(asctime)s - %(name)s - %(levelname)s - %(message)s', level=logging.INFO )
logging.getLogger("httpx").setLevel(logging.WARNING)
logging.getLogger("telegram.ext").setLevel(logging.INFO)
logging.getLogger('telegram.bot').setLevel(logging.INFO)
logging.getLogger("urllib3").setLevel(logging.INFO)
logging.getLogger('gunicorn.error').setLevel(logging.INFO)
logging.getLogger('uvicorn').setLevel(logging.INFO)
logging.getLogger('starlette').setLevel(logging.INFO)
if _gemini_available: logging.getLogger("google.ai.generativelanguage").setLevel(logging.WARNING)
logger = logging.getLogger(__name__)
logger.info(f"Logging configured. Using BS4 parser: {DEFAULT_PARSER}")
if not _gemini_available: logger.warning("google-generativeai library not found. Gemini functionality disabled.")


# --- Global variable for PTB app ---
ptb_app: Optional[Application] = None

# --- Environment Variable Loading & Configuration ---
logger.info("Attempting to load secrets and configuration...")
def get_secret(secret_name):
    value = os.environ.get(secret_name)
    if value: status = "Found"; log_length = min(len(value), 8); value_start = value[:log_length]; logger.info(f"Secret '{secret_name}': {status} (Value starts with: {value_start}...)")
    else: status = "Not Found"; logger.warning(f"Secret '{secret_name}': {status}")
    return value

TELEGRAM_TOKEN = get_secret('TELEGRAM_TOKEN')
OPENROUTER_API_KEY = get_secret('OPENROUTER_API_KEY') # Now Fallback
URLTOTEXT_API_KEY = get_secret('URLTOTEXT_API_KEY')
SUPADATA_API_KEY = get_secret('SUPADATA_API_KEY')
APIFY_API_TOKEN = get_secret('APIFY_API_TOKEN')
WEBHOOK_SECRET = get_secret('WEBHOOK_SECRET')
GEMINI_API_KEY = get_secret('GEMINI_API_KEY') # Now Primary

# Models (User can still configure via env vars)
OPENROUTER_MODEL = os.environ.get("OPENROUTER_MODEL", "deepseek/deepseek-chat-v3-0324:free") # Fallback Model
APIFY_ACTOR_ID = os.environ.get("APIFY_ACTOR_ID", "karamelo~youtube-transcripts")
GEMINI_MODEL = os.environ.get("GEMINI_MODEL", "gemini-2.0-flash-001") # Primary Model

if not TELEGRAM_TOKEN: logger.critical("❌ FATAL: TELEGRAM_TOKEN not found."); raise RuntimeError("Exiting: Telegram token missing.")
if not GEMINI_API_KEY: logger.error("❌ ERROR: GEMINI_API_KEY not found. Primary summarization (Gemini) will fail.")
if not OPENROUTER_API_KEY: logger.warning("⚠️ WARNING: OPENROUTER_API_KEY not found. Fallback summarization will fail.")

_gemini_primary_enabled = _gemini_available and bool(GEMINI_API_KEY)
if not _gemini_available: logger.warning("⚠️ WARNING: google-generativeai library missing. Gemini disabled.")
elif not GEMINI_API_KEY: logger.warning("⚠️ WARNING: GEMINI_API_KEY not found or empty. Gemini disabled.")

_openrouter_fallback_enabled = bool(OPENROUTER_API_KEY)
if not _openrouter_fallback_enabled: logger.warning("⚠️ WARNING: OPENROUTER_API_KEY not found. Fallback disabled.")


if not URLTOTEXT_API_KEY: pass
if not SUPADATA_API_KEY: pass
if not APIFY_API_TOKEN: pass
if not WEBHOOK_SECRET: logger.info("Optional secret 'WEBHOOK_SECRET' not found. Webhook security disabled.")

logger.info("Secret loading and configuration check finished.")
logger.info(f"Using Gemini Model (Primary): {GEMINI_MODEL if _gemini_primary_enabled else 'DISABLED'}")
logger.info(f"Using OpenRouter Model (Fallback): {OPENROUTER_MODEL if _openrouter_fallback_enabled else 'DISABLED'}")
logger.info(f"Using Apify Actor (via REST): {APIFY_ACTOR_ID}")
_apify_token_exists = bool(APIFY_API_TOKEN)


if _gemini_primary_enabled:
    try: genai.configure(api_key=GEMINI_API_KEY); logger.info("Google GenAI client configured successfully.")
    except Exception as e: logger.error(f"Failed to configure Google GenAI client: {e}"); _gemini_primary_enabled = False

# --- Retry Decorator ---
@retry( stop=stop_after_attempt(4), wait=wait_exponential(multiplier=1, min=2, max=15), retry=retry_if_exception_type((NetworkError, RetryAfter, TimedOut, BadRequest)), before_sleep=before_sleep_log(logger, logging.WARNING), reraise=True )
async def retry_bot_operation(func, *args, **kwargs):
    try: return await func(*args, **kwargs)
    except BadRequest as e:
        ignore_errors = [ "message is not modified", "query is too old", "message to edit not found", "chat not found", "bot was blocked by the user", ]
        if any(err in str(e).lower() for err in ignore_errors): logger.warning(f"Ignoring non-critical BadRequest: {e}"); return None
        logger.error(f"Potentially critical BadRequest: {e}"); raise
    except TelegramError as e: logger.warning(f"TelegramError (will retry if applicable): {e}"); raise
    except Exception as e: logger.error(f"Unexpected error during bot operation: {e}", exc_info=True); raise

# --- Helper Functions ---
def is_youtube_url(url):
    youtube_regex = re.compile( r'(?:https?://)?(?:www\.)?(?:m\.)?(?:youtube(?:-nocookie)?\.com|youtu\.be)/' r'(?:watch\?v=|embed/|v/|shorts/|live/|attribution_link\?a=.*&u=/watch\?v=)?' r'([\w-]{11})' r'(?:\S+)?', re.IGNORECASE)
    match = youtube_regex.search(url); logger.debug(f"is_youtube_url '{url}': {bool(match)}"); return bool(match)
def extract_youtube_id(url):
    youtube_regex = re.compile( r'(?:https?://)?(?:www\.)?(?:m\.)?(?:youtube(?:-nocookie)?\.com|youtu\.be)/' r'(?:watch\?v=|embed/|v/|shorts/|live/|attribution_link\?a=.*&u=/watch\?v=)?' r'([\w-]{11})' r'(?:\S+)?', re.IGNORECASE)
    match = youtube_regex.search(url)
    if match: video_id = match.group(1); logger.debug(f"Extracted YT ID '{video_id}' from {url}"); return video_id
    else: logger.warning(f"Could not extract YT ID from {url}"); return None


# --- Content Fetching Functions ---
# (fetch_url_content_for_scrape, get_transcript_via_supadata, get_transcript_via_apify, get_youtube_transcript, get_website_content, get_website_content_via_api remain the same as previous version)
async def fetch_url_content_for_scrape(url: str, timeout: int = 25) -> Optional[str]:
    headers = { 'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.124 Safari/537.36', 'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8', 'Accept-Language': 'en-US,en;q=0.5', 'Connection': 'keep-alive', 'DNT': '1', 'Upgrade-Insecure-Requests': '1' }
    try:
        async with httpx.AsyncClient(follow_redirects=True, timeout=timeout, headers=headers) as client:
            logger.debug(f"[Web Scrape] Sending request to {url}")
            response = await client.get(url)
            logger.debug(f"[Web Scrape] Received response {response.status_code} from {url}")
            response.raise_for_status()
            content_type = response.headers.get('content-type', '').lower()
            if 'html' not in content_type: logger.warning(f"[Web Scrape] Non-HTML content type from {url}: {content_type}"); return None
            try: return response.text
            except Exception as e: logger.error(f"[Web Scrape] Error decoding response for {url}: {e}"); return None
    except httpx.HTTPStatusError as e: logger.error(f"[Web Scrape] HTTP error {e.response.status_code} fetching {url}: {e}")
    except httpx.TimeoutException: logger.error(f"[Web Scrape] Timeout error fetching {url}")
    except httpx.TooManyRedirects: logger.error(f"[Web Scrape] Too many redirects fetching {url}")
    except httpx.RequestError as e: logger.error(f"[Web Scrape] Request error fetching {url}: {e}")
    except Exception as e: logger.error(f"[Web Scrape] Unexpected error fetching {url}: {e}", exc_info=True)
    return None

async def get_transcript_via_supadata(video_id: str, api_key: str) -> Optional[str]:
    if not video_id: logger.error("[Supadata] No video_id provided"); return None
    if not api_key: logger.error("[Supadata] API key missing."); return None
    logger.info(f"[Supadata] Attempting fetch for video ID: {video_id}")
    api_endpoint = "https://api.supadata.ai/v1/youtube/transcript" # Corrected URL
    params = {"videoId": video_id, "format": "text"}; headers = {"X-API-Key": api_key}
    try:
        async with httpx.AsyncClient(timeout=30.0) as client:
            response = await client.get(api_endpoint, headers=headers, params=params)
            logger.debug(f"[Supadata] Status code {response.status_code} for {video_id}")
            if response.status_code == 200:
                try:
                    try: data = response.json()
                    except json.JSONDecodeError: data = None
                    content = None
                    if data: content = data if isinstance(data, str) else data.get("transcript") or data.get("text") or data.get("data")
                    if not content and response.text: content = response.text
                    if content and isinstance(content, str): logger.info(f"[Supadata] Success for {video_id}. Length: {len(content)}"); return content.strip()
                    else: logger.warning(f"[Supadata] Success but content empty/invalid for {video_id}. Response: {response.text[:200]}"); return None
                except Exception as e: logger.error(f"[Supadata] Error processing success response for {video_id}: {e}", exc_info=True); return None
            elif response.status_code in [401, 403]: logger.error(f"[Supadata] Auth error ({response.status_code}). Check API key."); return None
            elif response.status_code == 404: logger.warning(f"[Supadata] Not found (404) for {video_id}."); return None
            else: logger.error(f"[Supadata] Unexpected status {response.status_code} for {video_id}. Resp: {response.text[:200]}"); return None
    except httpx.TimeoutException: logger.error(f"[Supadata] Timeout connecting for {video_id}"); return None
    except httpx.RequestError as e:
        if "CERTIFICATE_VERIFY_FAILED" in str(e): logger.error(f"[Supadata] SSL Cert Verify Failed for {video_id}: {e}")
        else: logger.error(f"[Supadata] Request error for {video_id}: {e}")
        return None
    except Exception as e: logger.error(f"[Supadata] Unexpected error for {video_id}: {e}", exc_info=True); return None

async def get_transcript_via_apify(video_url: str, api_token: str) -> Optional[str]:
    """Fetches YouTube transcript using Apify REST API (run-sync-get-dataset-items endpoint)."""
    global APIFY_ACTOR_ID
    if not video_url: logger.error("[Apify SyncItems] No video_url provided"); return None
    if not api_token: logger.error("[Apify SyncItems] API token missing."); return None
    logger.info(f"[Apify SyncItems] Attempting fetch for URL: {video_url} (Actor: {APIFY_ACTOR_ID})")

    sync_items_endpoint = f"https://api.apify.com/v2/acts/{APIFY_ACTOR_ID}/run-sync-get-dataset-items"
    params = {"token": api_token}
    payload = { "urls": [video_url], "outputFormat": "singleStringText", "maxRetries": 5, "channelHandleBoolean": False, "channelNameBoolean": False, "datePublishedBoolean": False, "relativeDateTextBoolean": False, }
    headers = {"Content-Type": "application/json"}

    try:
        async with httpx.AsyncClient(timeout=120.0) as client:
            log_headers = {k: v for k, v in headers.items()}
            logger.debug(f"[Apify SyncItems] POST Request Details:\nURL: {sync_items_endpoint}\nParams: {params}\nHeaders: {log_headers}\nPayload: {json.dumps(payload)}")
            response = await client.post(sync_items_endpoint, headers=headers, params=params, json=payload)
            logger.debug(f"[Apify SyncItems] Received status code {response.status_code} for {video_url}")

            if response.status_code == 200:
                try:
                    results = response.json()
                    if isinstance(results, list) and len(results) > 0:
                        item = results[0]
                        content = None
                        if "captions" in item and isinstance(item["captions"], str): logger.info("[Apify SyncItems] Found 'captions' key with string content."); content = item["captions"]
                        elif "text" in item and isinstance(item["text"], str): logger.info("[Apify SyncItems] Found 'text' key with string content."); content = item["text"]
                        elif "transcript" in item and isinstance(item["transcript"], str): logger.info("[Apify SyncItems] Found 'transcript' key with string content."); content = item["transcript"]
                        elif "captions" in item and isinstance(item["captions"], list):
                             logger.warning("[Apify SyncItems] Received list format for 'captions' unexpectedly. Processing...")
                             if len(item["captions"]) > 0 and isinstance(item["captions"][0], dict) and 'text' in item["captions"][0]: content = " ".join(line.get("text", "") for line in item["captions"] if line.get("text"))
                             elif len(item["captions"]) > 0 and isinstance(item["captions"][0], str): content = " ".join(item["captions"])
                        if content and isinstance(content, str): logger.info(f"[Apify SyncItems] Success via REST for {video_url}. Length: {len(content)}"); return content.strip()
                        else: logger.warning(f"[Apify SyncItems] Dataset item parsed but transcript content empty/invalid format for {video_url}. Item keys: {list(item.keys())}"); return None
                    else: logger.warning(f"[Apify SyncItems] Actor success but dataset was empty for {video_url}. Response: {results}"); return None
                except json.JSONDecodeError: logger.error(f"[Apify SyncItems] Failed JSON decode. Status:{response.status_code}. Resp:{response.text[:200]}"); return None
                except Exception as e: logger.error(f"[Apify SyncItems] Error processing success response for {video_url}: {e}", exc_info=True); return None
            elif response.status_code == 400: logger.error(f"[Apify SyncItems] Bad Request (400) for {video_url}. Check payload. Resp:{response.text[:200]}"); return None
            elif response.status_code == 401: logger.error("[Apify SyncItems] Auth error (401). Check token."); return None
            elif response.status_code == 404:
                 error_info = "";
                 try: error_info = response.json().get("error", {}).get("message", "")
                 except Exception: pass
                 logger.error(f"[Apify SyncItems] Endpoint/Actor Not Found (404). Error: '{error_info}' Resp:{response.text[:200]}");
                 return None
            else: logger.error(f"[Apify SyncItems] Unexpected status {response.status_code} for {video_url}. Resp:{response.text[:200]}"); return None

    except httpx.TimeoutException as e: logger.error(f"[Apify SyncItems] Timeout during API interaction for {video_url}: {e}"); return None
    except httpx.HTTPStatusError as e: logger.error(f"[Apify SyncItems] HTTP Status Error during API interaction for {video_url}: {e}"); return None
    except httpx.RequestError as e: logger.error(f"[Apify SyncItems] Request error during API interaction for {video_url}: {e}"); return None
    except Exception as e: logger.error(f"[Apify SyncItems] Unexpected error during Apify SyncItems REST call for {video_url}: {e}", exc_info=True); return None

async def get_youtube_transcript(video_id: str, video_url: str) -> Optional[str]:
    global SUPADATA_API_KEY, APIFY_API_TOKEN
    if not video_id: logger.error("get_youtube_transcript: No video_id"); return None
    logger.info(f"Fetching transcript for video ID: {video_id} (URL: {video_url})")
    transcript_text = None
    logger.info("[Primary YT] Attempting youtube-transcript-api...")
    try:
        transcript_list = await asyncio.to_thread( YouTubeTranscriptApi.get_transcript, video_id, languages=['en', 'en-GB', 'en-US'] )
        if transcript_list: transcript_text = " ".join([item['text'] for item in transcript_list if 'text' in item])
        if transcript_text: logger.info(f"[Primary YT] Success via lib for {video_id} (len: {len(transcript_text)})"); return transcript_text
        else: logger.warning(f"[Primary YT] Transcript list/text empty for {video_id}"); transcript_text = None
    except Exception as e:
        logger.warning(f"[Primary YT] Error via lib for {video_id}: {e}")
        if "No transcript found" in str(e): logger.warning(f"[Primary YT] No transcript found.")
        elif "disabled" in str(e): logger.warning(f"[Primary YT] Transcripts disabled.")
        transcript_text = None
    if transcript_text is None:
        logger.info("[Fallback YT 1] Trying Supadata API...")
        if SUPADATA_API_KEY:
            transcript_text = await get_transcript_via_supadata(video_id, SUPADATA_API_KEY)
            if transcript_text: logger.info(f"[Fallback YT 1] Success via Supadata for {video_id}"); return transcript_text
            else: logger.warning(f"[Fallback YT 1] Supadata failed or no content for {video_id}.")
        else: logger.warning("[Fallback YT 1] Supadata API key unavailable. Skipping.")
    if transcript_text is None:
        logger.info("[Fallback YT 2] Trying Apify REST API (SyncItems)...")
        if APIFY_API_TOKEN:
            transcript_text = await get_transcript_via_apify(video_url, APIFY_API_TOKEN)
            if transcript_text: logger.info(f"[Fallback YT 2] Success via Apify SyncItems REST for {video_url}"); return transcript_text
            else: logger.warning(f"[Fallback YT 2] Apify SyncItems REST failed or no content for {video_url}.")
        else: logger.warning("[Fallback YT 2] Apify API token unavailable. Skipping.")
    if transcript_text is None: logger.error(f"All methods failed for YT transcript: {video_id}"); return None
    return transcript_text

async def get_website_content(url: str) -> Optional[str]:
    if not url: logger.error("get_website_content: No URL"); return None
    logger.info(f"[Primary Web] Fetching website content for: {url}")
    html_content = await fetch_url_content_for_scrape(url)
    if not html_content: return None
    try:
        def parse_html(content):
            soup = BeautifulSoup(content, DEFAULT_PARSER)
            for element in soup(["script", "style", "header", "footer", "nav", "aside", "form", "button", "input", "iframe", "img", "svg", "link", "meta", "noscript", "figure"]): element.extract()
            main_content = soup.find('main') or soup.find('article') or soup.find(id='content') or soup.find(class_='content') or soup.find(id='main-content') or soup.find(class_='main-content') or soup.find(role='main')
            target_element = main_content if main_content else soup.body
            if not target_element: logger.warning(f"[Primary Web] Could not find body/main for parsing {url}"); return None
            lines = [line.strip() for line in target_element.get_text(separator='\n', strip=True).splitlines() if line.strip()]
            text = " ".join(lines)
            if not text: logger.warning(f"[Primary Web] Extracted text empty after clean for {url}"); return None
            return text
        text_content = await asyncio.to_thread(parse_html, html_content)
        if text_content: logger.info(f"[Primary Web] Success scrape for {url} (final len: {len(text_content)})"); return text_content
        else: return None
    except Exception as e: logger.error(f"[Primary Web] Error scraping/parsing {url}: {e}", exc_info=True); return None

async def get_website_content_via_api(url: str, api_key: str) -> Optional[str]:
    if not url: logger.error("[Fallback Web API] No URL"); return None
    if not api_key: logger.error("[Fallback Web API] urltotext.com API key missing."); return None
    logger.info(f"[Fallback Web API] Attempting fetch for: {url} using urltotext.com API")
    api_endpoint = "https://urltotext.com/api/v1/urltotext/"
    payload = { "url": url, "output_format": "text", "extract_main_content": True, "render_javascript": True, "residential_proxy": False }
    headers = { "Authorization": f"Token {api_key}", "Content-Type": "application/json" }
    try:
        async with httpx.AsyncClient(timeout=45.0) as client:
            logger.debug(f"[Fallback Web API] Sending request to urltotext.com API for {url}")
            response = await client.post(api_endpoint, headers=headers, json=payload)
            logger.debug(f"[Fallback Web API] Received status {response.status_code} from urltotext.com API for {url}")
            if response.status_code == 200:
                try:
                    data = response.json()
                    content = data.get("data", {}).get("content"); credits = data.get("credits_used", "N/A"); warning = data.get("data", {}).get("warning")
                    if warning: logger.warning(f"[Fallback Web API] urltotext.com API Warning for {url}: {warning}")
                    if content: logger.info(f"[Fallback Web API] Success via urltotext.com API for {url}. Len: {len(content)}. Credits: {credits}"); return content.strip()
                    else: logger.warning(f"[Fallback Web API] urltotext.com API success but content empty for {url}. Resp: {data}"); return None
                except json.JSONDecodeError: logger.error(f"[Fallback Web API] Failed JSON decode urltotext.com for {url}. Resp:{response.text[:500]}"); return None
                except Exception as e: logger.error(f"[Fallback Web API] Error processing urltotext.com success response for {url}: {e}", exc_info=True); return None
            elif response.status_code in [400, 401, 402, 403, 422, 500]: logger.error(f"[Fallback Web API] Error {response.status_code} from urltotext.com API for {url}. Resp:{response.text[:200]}"); return None
            else: logger.error(f"[Fallback Web API] Unexpected status {response.status_code} from urltotext.com API for {url}. Resp:{response.text[:200]}"); return None
    except httpx.TimeoutException: logger.error(f"[Fallback Web API] Timeout connecting to urltotext.com API for {url}"); return None
    except httpx.RequestError as e: logger.error(f"[Fallback Web API] Request error connecting to urltotext.com API for {url}: {e}"); return None
    except Exception as e: logger.error(f"[Fallback Web API] Unexpected error during urltotext.com API call for {url}: {e}", exc_info=True); return None

# --- Summarization Functions ---

async def _call_gemini(text: str, summary_type: str) -> Tuple[Optional[str], Optional[str]]:
    """Internal function to call Gemini API. Returns (summary, error_message)."""
    global GEMINI_MODEL, _gemini_primary_enabled
    if not _gemini_primary_enabled:
        logger.error("[Gemini Primary] Called but is disabled.");
        return None, "Error: Primary AI service (Gemini) not configured/available."
    logger.info(f"[Gemini Primary] Generating {summary_type} summary using {GEMINI_MODEL}. Input length: {len(text)}")

    # Define prompts
    if summary_type == "paragraph":
        prompt = ("You are an AI model designed to provide concise summaries using British English spellings. Your output MUST be:\n"
                  "• Clear and simple language suitable for someone unfamiliar with the topic.\n"
                  "• Uses British English spellings throughout.\n"
                  "• Straightforward and understandable vocabulary; avoid complex terms.\n"
                  "• Presented as ONE SINGLE PARAGRAPH.\n"
                  "• No more than 85 words maximum; but does not have to be exactly 85.\n"
                  "• Considers the entire text content equally.\n"
                  "• Uses semicolons (;) instead of em dashes (– or —).\n"
                  "• **Focus ONLY on the main content; strictly EXCLUDE information about website features, subscriptions, ads, cookie notices, or navigation elements. Do not include things like free/paid tiers; basic/premium memberships. Especially for ACS membership.**\n\n" # Added instruction
                  "Here is the text to summarise:")
    else: # points summary
        prompt = ("You are an AI model designed to provide concise summaries using British English spellings. Your output MUST strictly follow this format:\n\n"
                  "• For each distinct topic or section identified in the text, create a heading.\n"
                  "• Each heading MUST be plain text without any formatting (e.g., Section Title).\n"
                  "• Immediately following each heading, list the key points as a bulleted list.\n"
                  "• Each bullet point MUST start with a hyphen and a space (- ) on a new line.\n"
                  "• The text within each bullet point should NOT contain any bold formatting.\n"
                  "• IMPORTANT: Never use bold formatting (double asterisks) within the text of the bullet points themselves.\n"
                  "• Use clear, simple, and straightforward language suitable for someone unfamiliar with the topic.\n"
                  "• Use British English spellings throughout.\n"
                  "• Avoid overly complex or advanced vocabulary.\n"
                  "• Keep bullet points concise.\n"
                  "• Ensure the entire summary takes no more than two minutes to read.\n"
                  "• Consider the entire text's content, not just the beginning or a few topics.\n"
                  "• Use semicolons (;) instead of em dashes (– or —).\n"
                  "• **Focus ONLY on the main content; strictly EXCLUDE information about website features, subscriptions, ads, cookie notices, or navigation elements. Do not include things like free/paid tiers; basic/premium memberships. Especially for ACS membership.**\n\n" # Added instruction
                  "Here is the text to summarise:")

    # Input Length Check (Gemini-specific limits if known, otherwise use a large default)
    MAX_INPUT_LENGTH_GEMINI = 1000000 # Default limit for Gemini
    if len(text) > MAX_INPUT_LENGTH_GEMINI:
        logger.warning(f"[Gemini Primary] Input length ({len(text)}) exceeds limit ({MAX_INPUT_LENGTH_GEMINI}). Truncating.");
        text = text[:MAX_INPUT_LENGTH_GEMINI] + "... (Content truncated)"
    full_prompt = f"{prompt}\n\n{text}"

    # Safety Settings (Block None)
    safety_settings = {
        HarmCategory.HARM_CATEGORY_HARASSMENT: HarmBlockThreshold.BLOCK_NONE,
        HarmCategory.HARM_CATEGORY_HATE_SPEECH: HarmBlockThreshold.BLOCK_NONE,
        HarmCategory.HARM_CATEGORY_SEXUALLY_EXPLICIT: HarmBlockThreshold.BLOCK_NONE,
        HarmCategory.HARM_CATEGORY_DANGEROUS_CONTENT: HarmBlockThreshold.BLOCK_NONE,
        getattr(HarmCategory, 'HARM_CATEGORY_CIVIC_INTEGRITY', None): HarmBlockThreshold.BLOCK_NONE
    }
    safety_settings = {k: v for k, v in safety_settings.items() if k is not None}
    logger.debug(f"[Gemini Primary] Using safety settings: {safety_settings}")

    try:
        logger.debug(f"[Gemini Primary] Initializing model {GEMINI_MODEL}")
        model = genai.GenerativeModel(GEMINI_MODEL)
        logger.info(f"[Gemini Primary] Sending request to Gemini ({GEMINI_MODEL})...")
        request_options = {"timeout": 120} # Generous timeout for Gemini
        response = await model.generate_content_async( full_prompt, safety_settings=safety_settings, request_options=request_options )
        logger.info("[Gemini Primary] Received response from Gemini.")

        # Check for immediate blocking reasons
        if response.prompt_feedback.block_reason:
            logger.warning(f"[Gemini Primary] Request blocked by API. Reason: {response.prompt_feedback.block_reason}");
            return None, f"Sorry, the primary AI model ({GEMINI_MODEL}) blocked the request (Reason: {response.prompt_feedback.block_reason})."

        # Check candidate-level blocking
        for cand in response.candidates:
            if cand.finish_reason == 'SAFETY':
                logger.warning(f"[Gemini Primary] Candidate blocked due to SAFETY. Ratings: {cand.safety_ratings}")
                return None, f"Sorry, the primary AI model ({GEMINI_MODEL}) blocked the response due to safety filters."

        # Try to get text, handle potential ValueError if blocked
        try:
            summary = response.text
        except ValueError as e:
            logger.warning(f"[Gemini Primary] Error accessing response text (likely blocked content): {e}");
            summary = None

        if summary:
            logger.info(f"[Gemini Primary] Success generating summary. Output len: {len(summary)}");
            # Escape Markdown for Telegram only if necessary (Removed escaping as it might conflict with plain heading)
            # escaped_summary = summary.strip().replace('_', r'\_').replace('*', r'\*').replace('[', r'\[').replace('`', r'\`')
            # Let's see if the AI respects the instruction without further escaping. If not, we might need selective escaping.
            return summary.strip(), None
        else:
            finish_reason = response.candidates[0].finish_reason if response.candidates else 'N/A'
            logger.warning(f"[Gemini Primary] Gemini returned empty summary or content was blocked. Finish reason: {finish_reason}");
            return None, f"Sorry, the primary AI model ({GEMINI_MODEL}) did not provide a summary (Finish Reason: {finish_reason})."

    except Exception as e:
        logger.error(f"[Gemini Primary] Unexpected error during Gemini API call: {e}", exc_info=True);
        return None, f"Sorry, an unexpected error occurred while using the primary AI service ({GEMINI_MODEL})."

async def _call_openrouter(text: str, summary_type: str) -> Tuple[Optional[str], Optional[str]]:
    """Internal function to call OpenRouter API (Fallback). Returns (summary, error_message)."""
    global OPENROUTER_API_KEY, OPENROUTER_MODEL, _openrouter_fallback_enabled
    if not _openrouter_fallback_enabled:
        logger.error("[OpenRouter Fallback] Called but is disabled.");
        return None, "Error: Fallback AI service (OpenRouter) not configured/available."
    logger.info(f"[OpenRouter Fallback] Generating {summary_type} summary using {OPENROUTER_MODEL}. Input length: {len(text)}")

    # Define prompts
    if summary_type == "paragraph":
        prompt = ("You are an AI model designed to provide concise summaries using British English spellings. Your output MUST be:\n"
                  "• Clear and simple language suitable for someone unfamiliar with the topic.\n"
                  "• Uses British English spellings throughout.\n"
                  "• Straightforward and understandable vocabulary; avoid complex terms.\n"
                  "• Presented as ONE SINGLE PARAGRAPH.\n"
                  "• No more than 85 words maximum; but does not have to be exactly 85.\n"
                  "• Considers the entire text content equally.\n"
                  "• Uses semicolons (;) instead of em dashes (– or —).\n"
                  "• **Focus ONLY on the main content; strictly EXCLUDE information about website features, subscriptions, ads, cookie notices, or navigation elements. Do not include things like free/paid tiers; basic/premium memberships. Especially for ACS membership.**\n\n" # Added instruction
                  "Here is the text to summarise:")
    else: # points summary
        prompt = ("You are an AI model designed to provide concise summaries using British English spellings. Your output MUST strictly follow this format:\n\n"
                  "• For each distinct topic or section identified in the text, create a heading.\n"
                  "• Each heading MUST be plain text without any formatting (e.g., Section Title).\n"
                  "• Immediately following each heading, list the key points as a bulleted list.\n"
                  "• Each bullet point MUST start with a hyphen and a space (- ) on a new line.\n"
                  "• The text within each bullet point should NOT contain any bold formatting.\n"
                  "• IMPORTANT: Never use bold formatting (double asterisks) within the text of the bullet points themselves.\n"
                  "• Use clear, simple, and straightforward language suitable for someone unfamiliar with the topic.\n"
                  "• Use British English spellings throughout.\n"
                  "• Avoid overly complex or advanced vocabulary.\n"
                  "• Keep bullet points concise.\n"
                  "• Ensure the entire summary takes no more than two minutes to read.\n"
                  "• Consider the entire text's content, not just the beginning or a few topics.\n"
                  "• Use semicolons (;) instead of em dashes (– or —).\n"
                  "• **Focus ONLY on the main content; strictly EXCLUDE information about website features, subscriptions, ads, cookie notices, or navigation elements. Do not include things like free/paid tiers; basic/premium memberships. Especially for ACS membership.**\n\n" # Added instruction
                  "Here is the text to summarise:")

    # Input Length Check (OpenRouter-specific limit)
    MAX_INPUT_LENGTH_OR = 500000
    if len(text) > MAX_INPUT_LENGTH_OR:
        logger.warning(f"[OpenRouter Fallback] Input length ({len(text)}) exceeds limit ({MAX_INPUT_LENGTH_OR}). Truncating.");
        text = text[:MAX_INPUT_LENGTH_OR] + "... (Content truncated)"
    full_prompt = f"{prompt}\n\n{text}"

    headers = { "Authorization": f"Bearer {OPENROUTER_API_KEY}", "Content-Type": "application/json" }
    payload = { "model": OPENROUTER_MODEL, "messages": [{"role": "user", "content": full_prompt}] }
    openrouter_api_endpoint = "https://openrouter.ai/api/v1/chat/completions"
    # Use reasonable timeouts for fallback
    api_timeouts = httpx.Timeout(25.0, read=20.0, write=25.0, pool=60.0)
    response = None

    try:
        async with httpx.AsyncClient(timeout=api_timeouts) as client:
            logger.info(f"[OpenRouter Fallback] Sending request to OpenRouter ({OPENROUTER_MODEL}) with read timeout {api_timeouts.read}s...")
            response = await client.post(openrouter_api_endpoint, headers=headers, json=payload)
            if response: logger.info(f"[OpenRouter Fallback] Received response from OpenRouter. Status code: {response.status_code}")
            else: logger.error("[OpenRouter Fallback] No response from OpenRouter (unexpected)."); return None, "Sorry, fallback AI service failed unexpectedly."

            if response.status_code == 200:
                try:
                    data = response.json()
                    if data.get("choices") and isinstance(data["choices"], list) and len(data["choices"]) > 0:
                        message = data["choices"][0].get("message")
                        if message and isinstance(message, dict):
                            summary = message.get("content")
                            if summary:
                                logger.info(f"[OpenRouter Fallback] Success via OpenRouter. Output len: {len(summary)}")
                                # Escape Markdown for Telegram only if necessary (Removed escaping)
                                # escaped_summary = summary.strip().replace('_', r'\_').replace('*', r'\*').replace('[', r'\[').replace('`', r'\`')
                                return summary.strip(), None
                            else:
                                logger.warning(f"[OpenRouter Fallback] OpenRouter success but content empty. Resp: {data}")
                                return None, "Sorry, the fallback AI model returned an empty summary."
                        else:
                            logger.error(f"[OpenRouter Fallback] Unexpected message structure: {message}. Full: {data}")
                            return None, "Sorry, could not parse fallback AI response (format)."
                    else:
                        logger.error(f"[OpenRouter Fallback] Unexpected choices structure: {data.get('choices')}. Full: {data}")
                        return None, "Sorry, could not parse fallback AI response (choices)."
                except json.JSONDecodeError:
                    logger.error(f"[OpenRouter Fallback] Failed JSON decode OpenRouter. Status:{response.status_code}. Resp:{response.text[:500]}")
                    return None, "Sorry, failed to understand fallback AI response."
                except Exception as e:
                    logger.error(f"[OpenRouter Fallback] Error processing OpenRouter success response: {e}", exc_info=True)
                    return None, "Sorry, error processing fallback AI response."
            # Handle specific error codes
            elif response.status_code == 401: logger.error("[OpenRouter Fallback] API key invalid (401)."); return None, "Error: Fallback AI model configuration key is invalid."
            elif response.status_code == 402: logger.error("[OpenRouter Fallback] Payment Required (402)."); return None, "Sorry, fallback AI service limits/payment issue."
            elif response.status_code == 429: logger.warning("[OpenRouter Fallback] Rate Limit Exceeded (429)."); return None, "Sorry, fallback AI model is busy. Try again."
            elif response.status_code == 500: logger.error(f"[OpenRouter Fallback] Internal Server Error (500). Resp:{response.text[:500]}"); return None, "Sorry, fallback AI service internal error."
            else:
                error_info = "";
                try: error_info = response.json().get("error", {}).get("message", "")
                except Exception: pass
                logger.error(f"[OpenRouter Fallback] Unexpected status {response.status_code}. Error: '{error_info}' Resp:{response.text[:500]}");
                return None, f"Sorry, fallback AI service returned unexpected status ({response.status_code})."

    except httpx.TimeoutException as e:
        logger.error(f"[OpenRouter Fallback] Timeout error ({type(e)}) connecting/reading from OpenRouter API: {e}")
        return None, f"Sorry, the fallback AI service ({OPENROUTER_MODEL}) timed out."
    except httpx.RequestError as e:
        logger.error(f"[OpenRouter Fallback] Request error connecting to OpenRouter API: {e}")
        return None, "Sorry, there was an error connecting to the fallback AI model service."
    except Exception as e:
        logger.error(f"[OpenRouter Fallback] Unexpected error during OpenRouter call: {e}", exc_info=True)
        return None, "Sorry, an unexpected error occurred while using the fallback AI service."

async def generate_summary(text: str, summary_type: str) -> str:
    """
    Generates summary using Gemini (Primary) and falls back to OpenRouter if needed.
    Ensures point-based summaries have plain text headings.
    """
    global _gemini_primary_enabled, _openrouter_fallback_enabled, GEMINI_MODEL, OPENROUTER_MODEL
    logger.info(f"[Summary Generation] Starting process. Primary: Gemini ({GEMINI_MODEL}), Fallback: OpenRouter ({OPENROUTER_MODEL})")

    final_summary: Optional[str] = None
    error_message: Optional[str] = None

    # --- Attempt 1: Gemini (Primary) ---
    if _gemini_primary_enabled:
        logger.info(f"[Summary Generation] Attempting primary AI: Gemini ({GEMINI_MODEL})")
        final_summary, error_message = await _call_gemini(text, summary_type)
        if final_summary:
            logger.info(f"[Summary Generation] Success with primary AI (Gemini).")
            # Return directly - prompt handles formatting
            return final_summary
        else:
            logger.warning(f"[Summary Generation] Primary AI (Gemini) failed or returned unusable result. Error: {error_message}. Proceeding to fallback.")
    else:
        logger.warning("[Summary Generation] Primary AI (Gemini) is disabled or unavailable. Proceeding directly to fallback.")
        error_message = "Primary AI (Gemini) unavailable." # Set initial error message

    # --- Attempt 2: OpenRouter (Fallback) ---
    if _openrouter_fallback_enabled:
        logger.info(f"[Summary Generation] Attempting fallback AI: OpenRouter ({OPENROUTER_MODEL})")
        fallback_summary, fallback_error = await _call_openrouter(text, summary_type)
        if fallback_summary:
            logger.info(f"[Summary Generation] Success with fallback AI (OpenRouter).")
            # Return directly - prompt handles formatting
            return fallback_summary
        else:
            logger.error(f"[Summary Generation] Fallback AI (OpenRouter) also failed. Error: {fallback_error}")
            # Combine error messages if possible
            if error_message: # Keep the primary error if it exists
                 return f"{error_message} Fallback AI ({OPENROUTER_MODEL}) also failed: {fallback_error}"
            else: # If primary was skipped
                 return f"Fallback AI ({OPENROUTER_MODEL}) failed: {fallback_error}"
    else:
        logger.error("[Summary Generation] Fallback AI (OpenRouter) is disabled or unavailable. Cannot proceed.")
        if error_message: # Return the primary error
            return f"{error_message} Fallback AI is also unavailable."
        else: # Should not happen if logic is correct, but safeguard
            return "Error: Both primary and fallback AI services are unavailable."

    # Should ideally not be reached if logic above is sound, but as a final catch
    logger.error("[Summary Generation] Reached end of function without returning a summary or specific error.")
    return "Sorry, an unknown error occurred during summary generation after trying all available models."


# (process_summary_task, handlers, setup, lifespan, routes, etc. remain the same)
async def process_summary_task( user_id: int, chat_id: int, message_id_to_edit: Optional[int], url: str, summary_type: str, bot_token: str ) -> None:
    task_id = f"{user_id}-{message_id_to_edit or 'new'}"; logger.info(f"[Task {task_id}] Starting processing for URL: {url}")
    background_request: Optional[BaseRequest] = None; bot: Optional[Bot] = None
    try: background_request = HTTPXRequest( connect_timeout=15.0, read_timeout=60.0, write_timeout=60.0, pool_timeout=60.0 ); bot = Bot(token=bot_token, request=background_request)
    except Exception as e: logger.critical(f"[Task {task_id}] Failed to create background bot: {e}", exc_info=True); return
    content = None; user_feedback_message = None; success = False; status_message_id = message_id_to_edit; message_to_delete_later_id : Optional[int] = None
    try:
        processing_message_text = f"Got it! Generating '{summary_type}' summary for:\n`{url}`\n\nThis might take a moment..."
        if status_message_id:
            try: await retry_bot_operation( bot.edit_message_text, chat_id=chat_id, message_id=status_message_id, text=processing_message_text, parse_mode=ParseMode.MARKDOWN, reply_markup=None ); logger.debug(f"[Task {task_id}] Edited message {status_message_id} to 'Processing'")
            except Exception as e: logger.warning(f"[Task {task_id}] Could not edit original message {status_message_id}: {e}. Sending new."); status_message_id = None
        if not status_message_id:
             try:
                 status_message = await retry_bot_operation( bot.send_message, chat_id=chat_id, text=processing_message_text, parse_mode=ParseMode.MARKDOWN )
                 if status_message: message_to_delete_later_id = status_message.message_id; logger.debug(f"[Task {task_id}] Sent new status message {message_to_delete_later_id}")
                 else: raise RuntimeError("Failed to send status message after retries.")
             except Exception as e: logger.error(f"[Task {task_id}] CRITICAL: Failed to send new status message: {e}"); raise
        try:
            await retry_bot_operation(bot.send_chat_action, chat_id=chat_id, action='typing')
            is_youtube = is_youtube_url(url); logger.debug(f"[Task {task_id}] URL type: {'YouTube' if is_youtube else 'Website'}")
            if is_youtube:
                video_id = extract_youtube_id(url)
                if video_id: content = await get_youtube_transcript(video_id, url)
                else: user_feedback_message = "Sorry, I couldn't understand that YouTube URL format."
                if not content and not user_feedback_message: user_feedback_message = "Sorry, I couldn't get the transcript for that YouTube video using any available method (unavailable/private/no captions?)."
            else:
                content = await get_website_content(url)
                if not content:
                    logger.warning(f"[Task {task_id}] Primary web scrape failed for {url}. Trying fallback API.")
                    global URLTOTEXT_API_KEY
                    if URLTOTEXT_API_KEY:
                         await retry_bot_operation(bot.send_chat_action, chat_id=chat_id, action='typing')
                         content = await get_website_content_via_api(url, URLTOTEXT_API_KEY)
                         if not content: user_feedback_message = "Sorry, I couldn't fetch content from that website using either method (blocked/inaccessible/empty?)."
                    else: user_feedback_message = "Sorry, I couldn't fetch content from that website (blocked/inaccessible/empty?). The fallback method is not configured."
            if content:
                logger.info(f"[Task {task_id}] Content fetched (len:{len(content)}). Generating summary.")
                await retry_bot_operation(bot.send_chat_action, chat_id=chat_id, action='typing')
                final_summary = await generate_summary(content, summary_type) # This now calls Gemini first, then OpenRouter
                if final_summary.startswith("Error:") or final_summary.startswith("Sorry,"): user_feedback_message = final_summary; logger.warning(f"[Task {task_id}] Summary generation failed: {final_summary}")
                else:
                    max_length = 4096; summary_parts = [final_summary[i:i+max_length] for i in range(0, len(final_summary), max_length)]
                    # Sending potentially unescaped summary directly - assuming AI follows instructions
                    # ParseMode.MARKDOWN might interpret unintended things, test needed. Consider ParseMode=None if issues arise.
                    await retry_bot_operation( bot.send_message, chat_id=chat_id, text=summary_parts[0], parse_mode=None, link_preview_options={'is_disabled': True} )
                    for part in summary_parts[1:]: await asyncio.sleep(0.5); await retry_bot_operation( bot.send_message, chat_id=chat_id, text=part, parse_mode=None, link_preview_options={'is_disabled': True} )
                    success = True; logger.info(f"[Task {task_id}] Successfully sent summary ({len(summary_parts)} parts)."); user_feedback_message = None
            elif user_feedback_message: logger.warning(f"[Task {task_id}] Sending failure feedback: {user_feedback_message}"); await retry_bot_operation( bot.send_message, chat_id=chat_id, text=user_feedback_message, link_preview_options={'is_disabled': True} )
        except Exception as e:
            logger.error(f"[Task {task_id}] Unexpected error during processing: {e}", exc_info=True); user_feedback_message = "Oops! Something went really wrong. Please try again later."
            try: await retry_bot_operation( bot.send_message, chat_id=chat_id, text=user_feedback_message )
            except Exception: logger.error(f"[Task {task_id}] Failed to send unexpected error feedback.")
    except Exception as outer_e:
        logger.critical(f"[Task {task_id}] Critical outer error: {outer_e}", exc_info=True)
        try:
             if bot: await retry_bot_operation( bot.send_message, chat_id=chat_id, text="❌ Critical internal error occurred." )
        except Exception: logger.exception(f"[Task {task_id}] Failed even to send critical error message.")
    finally:
        delete_target_id = message_to_delete_later_id if message_to_delete_later_id else status_message_id
        if delete_target_id and bot:
            try: await retry_bot_operation(bot.delete_message, chat_id=chat_id, message_id=delete_target_id); logger.debug(f"[Task {task_id}] Deleted status/button message {delete_target_id}")
            except Exception as del_e: logger.warning(f"[Task {task_id}] Failed to delete status/button message {delete_target_id}: {del_e}")
        if background_request and hasattr(background_request, '_client') and background_request._client:
             try: await background_request._client.aclose(); logger.debug(f"[Task {task_id}] Background bot's HTTPX client closed.")
             except Exception as e: logger.warning(f"[Task {task_id}] Error closing background bot's client: {e}")
        logger.info(f"[Task {task_id}] Task completed. Success: {success}")

async def start(update: Update, context: ContextTypes.DEFAULT_TYPE) -> None:
    user = update.effective_user; mention = user.mention_html()
    if not user or not update.message: return
    logger.info(f"User {user.id} used /start.")
    await update.message.reply_html( f"👋 Hello {mention}! I can summarise YouTube links or website URLs.\n\nJust send me a link anytime!" ) # Changed 'summarize'

async def help_command(update: Update, context: ContextTypes.DEFAULT_TYPE) -> None:
    user = update.effective_user
    if not user or not update.message: return
    logger.info(f"User {user.id} used /help.")
    help_text = ( "🔍 How to use this bot:\n\n" "1. Send me any YouTube video link or website URL.\n" "2. I'll ask you how you want it summarised (paragraph or points).\n" # Changed 'summarized'
                  "3. Click the button for your choice.\n" "4. Wait for the summary!\n\n" "I'll try multiple methods to get content if the first one fails (especially for YouTube transcripts).\n\n" "Commands:\n" "`/start` - Display welcome message\n" "`/help` - Show this help message" )
    await update.message.reply_text(help_text, parse_mode=ParseMode.MARKDOWN)

async def handle_potential_url(update: Update, context: ContextTypes.DEFAULT_TYPE) -> None:
    if not update.message or not update.message.text: return
    url = update.message.text.strip(); user = update.effective_user
    if not user: return
    if not (url.startswith('http://') or url.startswith('https://')) or '.' not in url[8:]: logger.debug(f"Ignoring non-URL from {user.id}: {url}"); return
    logger.info(f"User {user.id} sent potential URL: {url}")
    context.user_data['url_to_summarize'] = url; context.user_data['original_message_id'] = update.message.message_id
    keyboard = [[ InlineKeyboardButton("Paragraph Summary", callback_data="paragraph"), InlineKeyboardButton("Points Summary", callback_data="points") ]]
    reply_markup = InlineKeyboardMarkup(keyboard)
    await update.message.reply_text( f"Okay, I see this link:\n{url}\n\nHow would you like it summarised?", reply_markup=reply_markup, disable_web_page_preview=True ) # Changed 'summarized'

async def handle_summary_type_callback(update: Update, context: ContextTypes.DEFAULT_TYPE) -> None:
    query = update.callback_query
    if not query or not query.message or not query.from_user: logger.warning("Callback query missing data."); return
    user = query.from_user; summary_type = query.data; query_id = query.id
    try: await query.answer(); logger.debug(f"Ack callback {query_id} from {user.id}")
    except Exception as e: logger.error(f"Error answering callback {query_id}: {e}", exc_info=True)
    url = context.user_data.get('url_to_summarize'); message_id_to_edit = query.message.message_id
    logger.info(f"User {user.id} chose '{summary_type}' for msg {message_id_to_edit}. URL in context: {'Yes' if url else 'No'}")
    if not url:
        logger.warning(f"No URL in context for user {user.id} (cb {query_id}).")
        try: await query.edit_message_text(text="Sorry, I couldn't find the URL associated with this request. Please send the link again.")
        except Exception as e:
            logger.error(f"Failed edit 'URL not found' msg: {e}")
            try: await context.bot.send_message(chat_id=user.id, text="Sorry, context lost. Send link again.")
            except Exception: pass
        return

    context.user_data.pop('url_to_summarize', None); context.user_data.pop('original_message_id', None); logger.debug(f"Cleared URL context for user {user.id}")

    global TELEGRAM_TOKEN, GEMINI_API_KEY, OPENROUTER_API_KEY, _gemini_primary_enabled, _openrouter_fallback_enabled
    if not TELEGRAM_TOKEN:
        logger.critical("TG TOKEN missing!")
        try: await query.edit_message_text(text="❌ Bot config error.")
        except Exception: pass
        return
    if not _gemini_primary_enabled and not _openrouter_fallback_enabled:
        logger.critical("Neither Gemini nor OpenRouter API keys are configured/valid!")
        try: await query.edit_message_text(text="❌ AI config error: No models available.")
        except Exception: pass
        return
    elif not _gemini_primary_enabled:
         logger.warning("Primary AI (Gemini) is unavailable, will rely on fallback.")
         # No need to inform user unless fallback also fails later
    elif not _openrouter_fallback_enabled:
         logger.warning("Fallback AI (OpenRouter) is unavailable.")
         # No need to inform user unless primary fails later

    logger.info(f"Scheduling task for user {user.id}, chat {query.message.chat_id}, msg {message_id_to_edit}")
    asyncio.create_task( process_summary_task( user_id=user.id, chat_id=query.message.chat_id, message_id_to_edit=message_id_to_edit, url=url, summary_type=summary_type, bot_token=TELEGRAM_TOKEN ), name=f"SummaryTask-{user.id}-{message_id_to_edit}" )

async def error_handler(update: object, context: ContextTypes.DEFAULT_TYPE) -> None:
    ignore_errors = (AttributeError, )
    if isinstance(context.error, ignore_errors) and "object has no attribute" in str(context.error): logger.debug(f"Ignoring known/handled error in error_handler: {context.error}"); return
    logger.error("Exception while handling an update:", exc_info=context.error)

async def setup_bot_config() -> Application:
    logger.info("Configuring Telegram Application..."); global TELEGRAM_TOKEN
    if not TELEGRAM_TOKEN: raise ValueError("TELEGRAM_TOKEN missing.")
    custom_request = HTTPXRequest( connect_timeout=10.0, read_timeout=30.0, write_timeout=30.0, pool_timeout=60.0 )
    application = Application.builder().token(TELEGRAM_TOKEN).request(custom_request).build()
    application.add_handler(CommandHandler("start", start)); application.add_handler(CommandHandler("help", help_command))
    application.add_handler(MessageHandler(filters.TEXT & ~filters.COMMAND, handle_potential_url)); application.add_handler(CallbackQueryHandler(handle_summary_type_callback))
    application.add_error_handler(error_handler); logger.info("Telegram application handlers configured."); return application

@contextlib.asynccontextmanager
async def lifespan(app: Starlette):
    global ptb_app, WEBHOOK_SECRET, TELEGRAM_TOKEN
    logger.info("ASGI Lifespan: Startup initiated...");
    if not TELEGRAM_TOKEN: logger.critical("TG TOKEN missing."); raise RuntimeError("Telegram token missing.")
    try:
        ptb_app = await setup_bot_config(); await ptb_app.initialize(); bot_info = await ptb_app.bot.get_me(); logger.info(f"Bot initialized: @{bot_info.username} (ID: {bot_info.id})")
        current_webhook_info = await ptb_app.bot.get_webhook_info()
        if current_webhook_info and current_webhook_info.url:
            logger.info(f"Found existing webhook: {current_webhook_info.url}. Deleting...")
            try:
                if await ptb_app.bot.delete_webhook(drop_pending_updates=True): logger.info("Webhook deleted.")
                else: logger.warning("Failed delete webhook (API returned False).")
            except Exception as e: logger.warning(f"Could not delete webhook: {e}"); await asyncio.sleep(1)
        space_host = os.environ.get("SPACE_HOST"); webhook_path = "/webhook"; full_webhook_url = None
        if space_host:
            protocol = "https"; host = space_host.split('://')[-1]; full_webhook_url = f"{protocol}://{host.rstrip('/')}{webhook_path}"
            if full_webhook_url:
                logger.info(f"Setting webhook: {full_webhook_url}"); set_webhook_args = { "url": full_webhook_url, "allowed_updates": Update.ALL_TYPES, "drop_pending_updates": True }
                if WEBHOOK_SECRET: set_webhook_args["secret_token"] = WEBHOOK_SECRET; logger.info("Using webhook secret.")
                await asyncio.sleep(1.0)
                try:
                    await ptb_app.bot.set_webhook(**set_webhook_args); webhook_info = await ptb_app.bot.get_webhook_info()
                    if webhook_info.url == full_webhook_url: logger.info(f"Webhook set: URL='{webhook_info.url}', Secret={bool(WEBHOOK_SECRET)}")
                    else: logger.error(f"Webhook URL mismatch! Expected '{full_webhook_url}', Got '{webhook_info.url}'"); raise RuntimeError("Webhook URL mismatch.")
                    await ptb_app.start(); logger.info("PTB Application started (webhook mode).")
                except Exception as e: logger.error(f"FATAL: Failed set webhook: {e}", exc_info=True); raise RuntimeError(f"Failed set webhook: {e}") from e
            else: logger.critical("Could not construct webhook URL."); raise RuntimeError("Webhook URL undetermined.")
        else: logger.critical("SPACE_HOST missing."); raise RuntimeError("SPACE_HOST env var missing.")
        logger.info("ASGI Lifespan: Startup complete."); yield
    except Exception as startup_err:
        logger.critical(f"Application startup failed: {startup_err}", exc_info=True)
        if ptb_app:
             if ptb_app.running: await ptb_app.stop()
             await ptb_app.shutdown()
        raise
    finally:
        logger.info("ASGI Lifespan: Shutdown initiated...")
        if ptb_app:
            if ptb_app.running: logger.info("Stopping PTB..."); await ptb_app.stop()
            logger.info("Shutting down PTB..."); await ptb_app.shutdown(); logger.info("PTB Application shut down.")
        else: logger.info("PTB application not initialized or failed.")
        logger.info("ASGI Lifespan: Shutdown complete.")

async def health_check(request: Request) -> PlainTextResponse:
    global OPENROUTER_MODEL, GEMINI_MODEL, APIFY_ACTOR_ID, _apify_token_exists, _gemini_primary_enabled, _openrouter_fallback_enabled
    bot_status = "Not Initialized"
    if ptb_app and ptb_app.bot:
        try:
             if ptb_app.running: bot_info = await ptb_app.bot.get_me(); bot_status = f"Running (@{bot_info.username})"
             else: bot_status = "Initialized/Not running"
        except Exception as e: bot_status = f"Error checking status: {e}"
    return PlainTextResponse( f"TG Bot Summariser - Status: {bot_status}\n" # Changed 'Summarizer'
                              f"Primary Model: {GEMINI_MODEL if _gemini_primary_enabled else 'N/A (Disabled)'}\n"
                              f"Fallback Model: {OPENROUTER_MODEL if _openrouter_fallback_enabled else 'N/A (Disabled)'}\n"
                              f"Apify Actor: {APIFY_ACTOR_ID if _apify_token_exists else 'N/A (No Token)'}" )

async def telegram_webhook(request: Request) -> Response:
    global WEBHOOK_SECRET
    if not ptb_app: logger.error("Webhook recv but PTB not initialized."); return PlainTextResponse('Bot not initialized', status_code=503)
    if not ptb_app.running: logger.warning("Webhook recv but PTB not running."); return PlainTextResponse('Bot not running', status_code=503)
    try:
        if WEBHOOK_SECRET:
             token_header = request.headers.get("X-Telegram-Bot-Api-Secret-Token")
             if token_header != WEBHOOK_SECRET: logger.warning(f"Webhook invalid secret. Header: '{token_header}'"); return Response(content="Invalid secret token", status_code=403)
        update_data = await request.json(); update = Update.de_json(data=update_data, bot=ptb_app.bot); logger.debug(f"Processing update_id: {update.update_id} via webhook")
        await ptb_app.process_update(update); return Response(status_code=200) # OK
    except json.JSONDecodeError: logger.error("Webhook invalid JSON."); return PlainTextResponse('Bad Request: Invalid JSON', status_code=400)
    except Exception as e: logger.error(f"Error processing webhook update: {e}", exc_info=True); return Response(status_code=200) # OK despite error

app = Starlette( debug=False, lifespan=lifespan, routes=[ Route("/", endpoint=health_check, methods=["GET"]), Route("/webhook", endpoint=telegram_webhook, methods=["POST"]), ] )
logger.info("Starlette ASGI application created with native routes.")

if __name__ == '__main__':
    import uvicorn
    logger.warning("Running in development mode using Uvicorn directly")
    log_level = os.environ.get("LOGGING_LEVEL", "info").lower()
    local_port = int(os.environ.get('PORT', 8080))
    uvicorn.run("__main__:app", host='0.0.0.0', port=local_port, log_level=log_level, reload=True)