"""
Email Scheduler
Background job that runs every 5 minutes to fetch and process emails
Based on OmniSync scheduler with APScheduler
"""

import logging
from apscheduler.schedulers.asyncio import AsyncIOScheduler
from apscheduler.triggers.interval import IntervalTrigger
from datetime import datetime

from app.core.config import settings
from app.services.email_processor_service import EmailProcessorService

logger = logging.getLogger(__name__)


class EmailScheduler:
    """Background scheduler for email processing"""
    
    def __init__(self):
        self.scheduler = AsyncIOScheduler()
        self.processor = EmailProcessorService()
        self.enabled = settings.EMAIL_TO_TICKET_ENABLED
        self.interval_minutes = settings.EMAIL_PROCESS_INTERVAL_MINUTES
    
    def start(self):
        """Start the background scheduler"""
        if not self.enabled:
            logger.info("⏭️ Email scheduler disabled (EMAIL_TO_TICKET_ENABLED=false)")
            return
        
        logger.info(f"🚀 Starting email scheduler (interval: {self.interval_minutes} minutes)")
        
        # Add job with interval trigger
        self.scheduler.add_job(
            func=self._process_emails_job,
            trigger=IntervalTrigger(minutes=self.interval_minutes),
            id='email_processor',
            name='Email Processing Job',
            max_instances=1,  # Prevent overlapping runs
            replace_existing=True
        )
        
        self.scheduler.start()
        logger.info("✅ Email scheduler started successfully")
    
    def stop(self):
        """Stop the scheduler"""
        if self.scheduler.running:
            self.scheduler.shutdown(wait=True)
            logger.info("👋 Email scheduler stopped")
    
    async def _process_emails_job(self):
        """Job function that processes emails"""
        try:
            logger.info("🔄 Email processing job started...")
            
            start_time = datetime.now()
            stats = await self.processor.process_inbox()
            
            duration = (datetime.now() - start_time).total_seconds()
            
            logger.info(f"✅ Email processing complete: {stats} (duration: {duration:.1f}s)")
        
        except Exception as e:
            logger.error(f"❌ Email processing job failed: {e}")
    
    def run_manual(self):
        """Manually trigger email processing (for testing)"""
        logger.info("🚀 Manual email processing triggered")
        import asyncio
        asyncio.create_task(self._process_emails_job())


# Global scheduler instance
email_scheduler = EmailScheduler()