"""Run the M16 platform invariants against a ModelForge database and report each outcome.

Read-only. Used as a standalone operator check, and by the chaos harness before injection, after
injection and after recovery, so a scenario can prove it left no invariant broken.

    python scripts/m16_invariants.py --database-url postgresql+psycopg://... [--json]
"""

from __future__ import annotations

import argparse
import json
import sys
from pathlib import Path

from sqlalchemy import create_engine
from sqlalchemy.orm import Session

sys.path.insert(0, str(Path(__file__).resolve().parents[1] / "backend" / "src"))

from modelforge_api.services.invariants import (  # noqa: E402
    InvariantStatus,
    check_invariants,
)
from modelforge_api.settings import get_settings  # noqa: E402


def main(argv: list[str] | None = None) -> int:
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument("--database-url", default=None)
    parser.add_argument("--json", action="store_true", help="emit the full machine-readable report")
    parser.add_argument("--label", default="invariants", help="label used in the human summary")
    args = parser.parse_args(argv)

    url = args.database_url or get_settings().database_url
    engine = create_engine(url, pool_pre_ping=True)
    try:
        with Session(engine) as session:
            report = check_invariants(session)
    finally:
        engine.dispose()

    if args.json:
        print(report.model_dump_json(indent=2))
    else:
        print(f"{args.label}: {report.holding}/{report.checked} hold, {report.violated} violated")
        for item in report.results:
            mark = "OK  " if item.status is InvariantStatus.HOLDS else "FAIL"
            print(f"  {mark} {item.key:38} {item.detail}")
            for example in item.violations:
                print(f"         - {example}")
    return 0 if report.ok else 1


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