"""Project existing article sections into the section index.

`_rebuild_section_index` runs when an article is saved, so articles written
before that existed have no rows — the index was empty and section-level
retrieval had nothing to search.

    docker compose exec backend python -m scripts.backfill_section_index
    docker compose exec backend python -m scripts.backfill_section_index --apply
"""
import sys

from app.database import SessionLocal
from app.models.article import Article
from app.routers.articles import _rebuild_section_index


def main():
    apply_changes = "--apply" in sys.argv
    db = SessionLocal()
    try:
        articles = db.query(Article).all()
        sections = sum(len(a.sections or []) for a in articles)
        print(f"  articles : {len(articles)}")
        print(f"  sections : {sections}")
        if apply_changes:
            for article in articles:
                _rebuild_section_index(db, article)
            db.commit()
            print("  indexed and embedded.")
        else:
            print("\n  Re-run with --apply to build the index.")
    finally:
        db.close()


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