"""Scheduler for daily birthday notifications."""
import telebot
from datetime import datetime
from typing import Optional
from apscheduler.schedulers.blocking import BlockingScheduler
from apscheduler.triggers.cron import CronTrigger
import pytz
from database import get_db_session, User, Chat, UserChat
from messages import format_birthday_greeting
from config import Config


def send_birthday_notifications(bot: telebot.TeleBot) -> None:
    """Send birthday notifications to all chats for users with birthday today."""
    db = get_db_session()
    try:
        today = datetime.now().date()
        day = today.day
        month = today.month
        
        # Get all users with birthday today
        users_with_birthday = db.query(User).filter(
            User.birthday_day == day,
            User.birthday_month == month
        ).all()
        
        if not users_with_birthday:
            return
        
        # For each user, send greetings to all their chats
        for user in users_with_birthday:
            # Get all chats where user is a member
            user_chats = db.query(Chat).join(UserChat).filter(
                UserChat.user_id == user.user_id,
                Chat.bot_is_admin == True
            ).all()
            
            greeting = format_birthday_greeting(user.first_name, user.preference_theme)
            
            for chat in user_chats:
                try:
                    # Check if user is still in chat
                    member = bot.get_chat_member(chat.chat_id, user.user_id)
                    if member.status not in ['left', 'kicked']:
                        bot.send_message(chat.chat_id, greeting)
                except telebot.apihelper.ApiTelegramException as e:
                    # Handle errors: user blocked bot, bot removed from chat, etc.
                    if e.error_code == 403:
                        # Bot was blocked or removed from chat
                        # Update chat status
                        chat.bot_is_admin = False
                        db.commit()
                    elif e.error_code == 400:
                        # Invalid chat or user
                        pass
                    # Silently continue for other errors
                except Exception:
                    # Other errors - continue
                    pass
    finally:
        db.close()


def setup_scheduler(bot: telebot.TeleBot) -> BlockingScheduler:
    """Setup and start the scheduler for daily birthday notifications."""
    # Parse notification time
    time_str: str = Config.NOTIFICATION_TIME
    try:
        hour, minute = map(int, time_str.split(':'))
    except (ValueError, AttributeError):
        hour, minute = 9, 0  # Default to 9:00
    
    # Get timezone
    timezone_str: str = Config.TIMEZONE
    try:
        tz = pytz.timezone(timezone_str)
    except (pytz.exceptions.UnknownTimeZoneError, AttributeError):
        tz = pytz.UTC
    
    # Create scheduler
    scheduler = BlockingScheduler(timezone=tz)
    
    # Add daily job
    scheduler.add_job(
        send_birthday_notifications,
        trigger=CronTrigger(hour=hour, minute=minute),
        args=[bot],
        id='daily_birthday_notifications',
        name='Send daily birthday notifications',
        replace_existing=True
    )
    
    return scheduler