import asyncio
import logging
import signal
from pathlib import Path

import click

from .core.logging_setup import configure_logging

# How long a stop waits for requests in flight (and SSE streams) to finish.
GRACEFUL_TIMEOUT_SECONDS = 10.0


def hypercorn_config(host: str, port: int):
    """Hypercorn as the production server (#5159): one worker, because Steward
    keeps run, stream and scheduler state in-process; its access and error
    lines go through Steward's logging, so the log.level setting governs them."""
    from hypercorn.config import Config

    config = Config()
    config.bind = [f"{host}:{port}"]
    config.workers = 1
    config.graceful_timeout = GRACEFUL_TIMEOUT_SECONDS
    config.accesslog = logging.getLogger("hypercorn.access")
    config.errorlog = logging.getLogger("hypercorn.error")
    config.access_log_format = "%(h)s %(r)s %(s)s %(b)s %(D)s"
    return config


async def _serve(app, config) -> None:
    from hypercorn.asyncio import serve

    stop = asyncio.Event()
    loop = asyncio.get_running_loop()
    for sig in (signal.SIGTERM, signal.SIGINT):
        loop.add_signal_handler(sig, stop.set)
    await serve(app, config, shutdown_trigger=stop.wait)


@click.command()
@click.option("--config", default="config.yaml", help="Path to config.yaml")
@click.option("--host", default="0.0.0.0")
@click.option("--port", default=5000, type=int)
@click.option("--debug", is_flag=True, default=False,
              help="Quart's development server with the reloader, not Hypercorn.")
def main(config: str, host: str, port: int, debug: bool) -> None:
    """Start the Steward server."""
    # Before anything logs; create_app applies the log.level setting once
    # settings load.
    configure_logging()
    from .app import create_app
    app = create_app(config_path=Path(config))
    if debug:
        app.run(host=host, port=port, debug=True)
        return
    asyncio.run(_serve(app, hypercorn_config(host, port)))