import serial
import requests
import os
from dotenv import load_dotenv
import logging
import signal
import time

load_dotenv()

##########################################
#Logging
if os.environ['logging_level'] == "DEBUG":
    loglevel = logging.DEBUG
elif os.environ['logging_level'] == "INFO":
    loglevel = logging.INFO
logger = logging.getLogger('Power Monitor')
logger.setLevel(loglevel)
#Console Handler
ch = logging.StreamHandler()
ch.setLevel(loglevel)
#Formatter
formatter = logging.Formatter('[%(asctime)s] [%(levelname)s] %(message)s')
formatter.default_msec_format = None
ch.setFormatter(formatter)
if not logger.handlers:
    logger.addHandler(ch)
##########################################

ntfy_token = os.environ['NTFY_Token']
device_name = os.environ['device_name']
shutdown_timer = int(os.environ['shutdown_timer'])

running = True

def handle_shutdown(signum, frame):
    global running
    logger.info("Received shutdown signal, exiting...")
    running = False

signal.signal(signal.SIGTERM, handle_shutdown)
signal.signal(signal.SIGINT, handle_shutdown)


def main():
    with serial.Serial(device_name, 115200, timeout=1) as ser:
        shutdown_triggered = False
        inverter_online = True
        last_online = time.monotonic()
        receiving_data = True
        last_logged = -1
        try:
            while running:
                line = ser.readline().decode(errors="ignore").strip()

                if line != "" and not receiving_data:
                    receiving_data = True
                    logger.info("Serial data restored")

                if line == "0":
                    if not inverter_online:
                        logger.info("Inverter restored")
                    inverter_online = True
                    last_online = time.monotonic()

                elif line == "1":
                    if inverter_online:
                        inverter_online = False
                        logger.info("Running on UPS reserve")

                elif line == "":
                    if receiving_data:
                        receiving_data = False
                        logger.warning("No serial data")

                else:
                    logger.warning(f"Unexpected serial data: {line}")

                if not inverter_online:
                    sec = int(time.monotonic() - last_online)

                    if sec % 10 == 0 and sec != last_logged:
                        logger.info(f"Offline for {sec}s")
                        last_logged = sec

                    if sec >= shutdown_timer:
                        shutdown_triggered = True
                        break
            if shutdown_triggered:
                logger.info(f"Inverter offline for {shutdown_timer} seconds")
                try:
                    requests.post(
                        "https://ntfy.fieryeagle.org/Internet-Alerts",
                        data="Inverter offline, shutting down".encode("utf-8"),
                        headers={
                            "Title": "Hydrogen running on reserve power",
                            "Authorization": f"Bearer {ntfy_token}"
                        },
                        timeout=5
                    )
                except Exception as e:
                    logger.error(f"Failed to send notification: {e}")
                os.system("shutdown now")
            else:
                logger.info("Exited cleanly (service stop)")
        except serial.SerialException as e:
            logger.error(f"Serial device error: {e}")
            raise

if __name__ == "__main__":
    main()