"""
Utility functions and decorators for the bot.
"""
import os
import functools
import logging
from telegram import Update
from telegram.ext import ContextTypes

logger = logging.getLogger(__name__)


def get_admin_ids():
    """Get the list of admin user IDs from environment variable."""
    admin_ids_str = os.getenv("ADMIN_IDS", "")
    if not admin_ids_str:
        logger.warning("ADMIN_IDS not set in .env file. No admins configured.")
        return set()
    
    try:
        # Parse comma-separated list of IDs
        admin_ids = set(int(id.strip()) for id in admin_ids_str.split(",") if id.strip())
        return admin_ids
    except ValueError as e:
        logger.error(f"Error parsing ADMIN_IDS: {e}")
        return set()


def admin_only(func):
    """
    Decorator that restricts command to admin users only.
    
    Usage:
        @admin_only
        async def my_admin_command(update: Update, context: ContextTypes.DEFAULT_TYPE):
            ...
    """
    @functools.wraps(func)
    async def wrapper(update: Update, context: ContextTypes.DEFAULT_TYPE, *args, **kwargs):
        user_id = update.effective_user.id
        admin_ids = get_admin_ids()
        
        if user_id not in admin_ids:
            await update.message.reply_html(
                "🚫 <b>Access Denied</b>\n\n"
                "This command is restricted to administrators only."
            )
            logger.warning(f"User {user_id} attempted to use admin command: {func.__name__}")
            return
        
        # User is admin, execute the command
        return await func(update, context, *args, **kwargs)
    
    return wrapper


def is_admin(user_id: int) -> bool:
    """Check if a user ID is an admin."""
    admin_ids = get_admin_ids()
    return user_id in admin_ids