#!/usr/bin/env python3
"""Scheduler loop for the news scraper — hourly scrape at minute :00.

Replaces the k8s CronJob (`0 * * * *`) with an in-compose loop so the whole
news pipeline lives inside docker-compose. Each iteration:

  1. (optionally, on first boot) runs the Scrapy crawl once to seed data fast
  2. sleeps until the next :NEWS_SCRAPE_MINUTE wall-clock boundary

Because the loop is serial, a crawl that overruns its hour simply delays the
next run to the following boundary — two crawls never overlap.

Env (all optional, 12-factor):
  NEWS_SCRAPE_MINUTE        minute of the hour to fire (default 0)
  NEWS_SCRAPE_RUN_ON_START  "1" to crawl once immediately on boot (default 1)
"""

from __future__ import annotations

import datetime
import logging
import os
import subprocess
import sys
import time

logging.basicConfig(level=logging.INFO, format="%(asctime)s %(levelname)s %(name)s: %(message)s")
logger = logging.getLogger("news.scraper")

MINUTE = int(os.getenv("NEWS_SCRAPE_MINUTE", "0"))
RUN_ON_START = os.getenv("NEWS_SCRAPE_RUN_ON_START", "1").lower() in ("1", "true", "yes")

CRAWL_CMD = ["scrapy", "crawl", "articles"]


def seconds_until_next(minute: int) -> float:
    """Seconds until the next occurrence of ``minute`` past the hour (local time)."""
    now = datetime.datetime.now()
    nxt = now.replace(minute=minute, second=0, microsecond=0) + datetime.timedelta(hours=1)
    return (nxt - now).total_seconds()


def run_crawl() -> None:
    logger.info("scrape starting at %s", datetime.datetime.now().isoformat(timespec="seconds"))
    try:
        proc = subprocess.run(CRAWL_CMD, cwd="/app")
        logger.info("scrape finished rc=%s", proc.returncode)
    except Exception:  # noqa: BLE001 — keep the loop alive across failures
        logger.exception("scrape failed")


def main() -> None:
    logger.info(
        "news scraper loop starting (minute=%s, run_on_start=%s)",
        MINUTE, RUN_ON_START,
    )
    if RUN_ON_START:
        run_crawl()
    while True:
        delay = seconds_until_next(MINUTE)
        logger.info("next scrape at :%02d (in %.0fs)", MINUTE, delay)
        time.sleep(delay)
        run_crawl()


if __name__ == "__main__":
    sys.exit(main())