"""Validate a READ-Bench submission before opening a PR.

Checks the submission folder is well-formed and (optionally) re-runs the
official harness to verify the reported numbers. Run::

    python validate_submission.py --submission submissions/my-method          # structure only
    python validate_submission.py --submission submissions/my-method --run    # + recompute scores

Exits non-zero on any failure, so it doubles as a CI gate.
"""

from __future__ import annotations

import argparse
import json
import sys
from pathlib import Path

REQUIRED_FILES = ["method.py", "metadata.yaml", "requirements.txt"]
REQUIRED_META = ["name", "slug", "family", "supervision"]
FAMILIES = {"Raw-window distance", "Symbolic", "FM embedder", "Fusion",
            "Reranker", "Supervised", "Other"}
SUPERVISION = {"label-free", "neighbour-labels", "supervised"}


def _fail(msg: str) -> None:
    print(f"  ✗ {msg}")


def _ok(msg: str) -> None:
    print(f"  ✓ {msg}")


def validate(submission: Path, run: bool, token: str = None) -> bool:
    import yaml

    print(f"Validating {submission}")
    ok = True

    for f in REQUIRED_FILES:
        if (submission / f).exists():
            _ok(f"{f} present")
        else:
            _fail(f"missing {f}")
            ok = False

    meta = {}
    if (submission / "metadata.yaml").exists():
        meta = yaml.safe_load((submission / "metadata.yaml").read_text()) or {}
        for key in REQUIRED_META:
            if meta.get(key):
                _ok(f"metadata.{key} = {meta[key]!r}")
            else:
                _fail(f"metadata.{key} missing/empty")
                ok = False
        if meta.get("family") and meta["family"] not in FAMILIES:
            _fail(f"family must be one of {sorted(FAMILIES)}")
            ok = False
        if meta.get("supervision") and meta["supervision"] not in SUPERVISION:
            _fail(f"supervision must be one of {sorted(SUPERVISION)}")
            ok = False

    # method.py must import and expose rank(query, corpus).
    try:
        from eval_submission import load_method
        load_method(submission)
        _ok("method.py exposes rank(query, corpus)")
    except Exception as exc:  # noqa: BLE001
        _fail(f"method.py not loadable: {type(exc).__name__}: {exc}")
        ok = False

    if run and ok:
        print("Running official harness (this downloads the dataset)…")
        try:
            from eval_submission import evaluate
            results = evaluate(submission, token=token)
            out = submission / "results.json"
            out.write_text(json.dumps(results, indent=2))
            h = results["headline"]
            _ok(f"scored NDCG@10 rho0/10/20 = "
                f"{h['rho0']:.4f}/{h['rho10']:.4f}/{h['rho20']:.4f} -> {out.name}")
        except Exception as exc:  # noqa: BLE001
            _fail(f"harness failed: {type(exc).__name__}: {exc}")
            ok = False

    print("PASS ✅" if ok else "FAIL ❌")
    return ok


def main(argv=None) -> None:
    p = argparse.ArgumentParser(description=__doc__,
                                formatter_class=argparse.RawDescriptionHelpFormatter)
    p.add_argument("--submission", required=True, type=Path)
    p.add_argument("--run", action="store_true", help="also recompute scores via the harness")
    p.add_argument("--token", default=None)
    args = p.parse_args(argv)
    sys.exit(0 if validate(args.submission, args.run, args.token) else 1)


if __name__ == "__main__":
    main()