import os
import signal
import traceback
from threading import Event
from time import sleep, time

from prometheus_client import start_http_server

import ingestor.metrics as metrics
from ingestor.ingestor import Ingestor

exit_signal = Event()
POD_ID = os.getenv("HOSTNAME", "localhost")


def main():
    start_prometheus_server()
    ingestor = Ingestor()
    try:
        ingestor.prepare_ingestor()
    except Exception as e:
        metrics.APP_ERRORS_TOTAL.labels(
            pod_id=POD_ID).inc()  # Increment errors
        ingestor.logger.error("Failed to prepare ingestor: %s", e)
        exit_signal.set()
    ingestor.logger.info("Ingestor prepared. Starting main loop.")

    while not exit_signal.is_set():
        start_time = time()  # Start loop timer
        try:
            ingestor.loop()
            metrics.APP_LOOP_COUNT.labels(
                pod_id=POD_ID).inc()  # Increment loop counter

            exit_signal.wait(ingestor.poll_interval)

        except KeyboardInterrupt:  # Handle Ctrl+C gracefully
            print("KeyboardInterrupt received. Setting exit_signal flag.")
            exit_signal.set()
        except Exception:
            print("Exception in main loop. Setting exit_signal flag.")
            traceback.print_exc()
            metrics.APP_ERRORS_TOTAL.labels(
                pod_id=POD_ID).inc()  # Increment errors
            exit_signal.set()
        finally:
            # Record loop duration
            duration = time() - start_time
            metrics.APP_LOOP_DURATION.labels(pod_id=POD_ID).observe(duration)

    ingestor.shutdown()
    metrics.APP_UP.labels(pod_id=POD_ID).set(0)  # Mark app as DOWN

    ingestor.logger.info("Main loop exit_signaled.")

    # Give Prometheus a chance to scrape one last time before exiting (optional)
    sleep(5)

    os._exit(0)


def signal_handler(_signum, _frame):
    print(f"Received signal {_signum}. Setting exit_signal flag.")
    exit_signal.set()


def start_prometheus_server():
    try:
        port = int(os.getenv("HTTP_SERVER_PORT", 4840))
        start_http_server(port)
        print(f"Prometheus server started on port {port}.")
        metrics.APP_UP.labels(pod_id=POD_ID).set(1)  # Mark app as UP
    except Exception as e:
        print(f"Failed to start Prometheus server: {e}")
        os._exit(1)


if __name__ == "__main__":
    signal.signal(signal.SIGINT, signal_handler)
    signal.signal(signal.SIGTERM, signal_handler)
    signal.signal(signal.SIGHUP, signal_handler)
    main()