"""CLI entry point: ``python -m jobsource.main``.

Parses arguments and delegates to :func:`~jobsource.pipeline.run_batch`.
All heavy imports are deferred past the argument parse so ``--help`` exits
immediately with no dependency overhead.

Usage examples::

    python -m jobsource.main --help
    python -m jobsource.main --batch-size 20 --search "software engineer" --location "United States"
    python -m jobsource.main --search "data engineer" --search "ML engineer" --hours-old 48
"""
from __future__ import annotations

import argparse
import logging
import sys


def build_parser() -> argparse.ArgumentParser:
    parser = argparse.ArgumentParser(
        prog="python -m jobsource.main",
        description=(
            "AI Job Source Agent -- emit company_name, career_page_url, "
            "open_position_url for recently posted LinkedIn jobs."
        ),
    )
    parser.add_argument(
        "--batch-size",
        type=int,
        default=None,
        help="Number of new jobs to process this run (default from config).",
    )
    parser.add_argument(
        "--search",
        action="append",
        metavar="TERM",
        help="Search term; repeatable. Overrides config search terms.",
    )
    parser.add_argument(
        "--location",
        default=None,
        help="Job location filter (default from config).",
    )
    parser.add_argument(
        "--hours-old",
        type=int,
        default=None,
        help="Only jobs posted within this many hours (default from config).",
    )
    return parser


def main(argv: list[str] | None = None) -> int:
    args = build_parser().parse_args(argv)

    # Configure root logger so pipeline/cascade INFO and WARNING messages are
    # visible on the terminal.  Deferred past parse_args so --help stays instant.
    logging.basicConfig(
        level=logging.INFO,
        format="%(asctime)s %(levelname)-8s %(name)s: %(message)s",
        datefmt="%H:%M:%S",
    )

    from jobsource.pipeline import run_batch  # deferred: keeps --help fast before heavy deps
    run_batch(
        batch_size=args.batch_size,
        search_terms=args.search,   # None or list[str] from --search repeats
        location=args.location,
        hours_old=args.hours_old,
    )
    return 0


if __name__ == "__main__":
    raise SystemExit(main())