#!/usr/bin/env python3
"""
Modbus to MQTT Bridge Service

This service reads temperature and humidity data from a Modbus TCP server
and publishes the data to an MQTT broker.

Usage:
    python main.py

Author: POE Project
"""

import time
import logging
import sys
import signal
from health_check import HealthCheckServer
from sensor_bridge import main_loop

# Global health server for cleanup
health_server = None

def signal_handler(signum, frame):
    """Handle shutdown signals gracefully"""
    global health_server
    logging.info(f"Received signal {signum}, shutting down gracefully...")
    if health_server:
        health_server.stop()
    sys.exit(0)

if __name__ == "__main__":
    # Setup logging
    logging.basicConfig(
        level=logging.INFO, 
        format='%(asctime)s - %(levelname)s - %(message)s',
        handlers=[
            logging.StreamHandler(sys.stdout),
        ]
    )
    
    # Setup signal handlers
    signal.signal(signal.SIGTERM, signal_handler)
    signal.signal(signal.SIGINT, signal_handler)
    
    logging.info("POE Sensor Bridge starting up...")
    
    try:
        # Start health check server first
        logging.info("Starting health check server...")
        health_server = HealthCheckServer()
        
        if health_server.start():
            logging.info("Health check server started successfully")
            
            # Give health check server time to be ready
            time.sleep(3)
            
            # Verify health check is working
            if health_server.is_running():
                logging.info("Health check server verified as running")
                logging.info("Starting main sensor loop...")
                main_loop()
            else:
                logging.error("Health check server failed to start properly")
                sys.exit(1)
        else:
            logging.error("Failed to start health check server")
            sys.exit(1)
            
    except KeyboardInterrupt:
        logging.info("Received keyboard interrupt, shutting down...")
    except Exception as e:
        logging.error(f"Fatal error: {e}", exc_info=True)
        sys.exit(1)
    finally:
        if health_server:
            health_server.stop()
        logging.info("POE Sensor Bridge shutdown complete")