#!/usr/bin/env python3
"""Validate question-to-image joins without calling a model or inventing outputs."""

import argparse
import hashlib
import json
import tarfile
from pathlib import Path, PurePosixPath


def rows(path):
    return [json.loads(line) for line in path.read_text(encoding="utf-8").splitlines() if line.strip()]


def relative_file(root, relative):
    path = PurePosixPath(relative)
    if path.is_absolute() or ".." in path.parts or "\\" in relative:
        raise ValueError("Unsafe relative file")
    candidate = root / relative
    candidate.resolve().relative_to(root.resolve())
    return candidate


def main():
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument("--questions", type=Path, required=True)
    parser.add_argument("--source-root", type=Path, help="Internal audit only: use original media tree and fallback tar")
    parser.add_argument("--limit", type=int)
    args = parser.parse_args()
    if args.limit is not None and args.limit < 1:
        parser.error("limit must be positive")
    root = Path(__file__).resolve().parents[1]
    manifest_rows = rows(root / "media_manifest.jsonl")
    manifest = {row["image_id"]: row for row in manifest_rows}
    if len(manifest) != len(manifest_rows):
        raise ValueError("Duplicate media IDs")
    sources = {}
    if args.source_root:
        sources = {row["image_id"]: row["source_relative_path"] for row in rows(root / "internal/media_sources.jsonl")}
    selected = rows(args.questions)
    if len({row["item_id"] for row in selected}) != len(selected):
        raise ValueError("Duplicate question IDs")
    if args.limit:
        selected = selected[:args.limit]
    checked = set()
    failures = []
    archive = None
    try:
        for question in selected:
            domain = {"是", "否"} if question["answer_type"] == "binary" else {"A", "B", "C", "D"}
            if question["ground_truth"] not in domain:
                raise ValueError("Invalid answer domain")
            for part in question["input"]:
                if part["type"] != "image_url":
                    continue
                reference = part["image_url"]["url"]
                if not reference.startswith("asset://"):
                    raise ValueError("Unexpected image URI")
                image_id = reference[len("asset://"):]
                if image_id in checked:
                    continue
                image = manifest[image_id]
                checked.add(image_id)
                try:
                    if args.source_root:
                        if image["status"] == "archived_only":
                            if archive is None:
                                archive = tarfile.open(relative_file(args.source_root, "data/non_bmp_image_fallback.tar"))
                            member = archive.getmember(sources[image_id])
                            if not member.isfile():
                                raise ValueError("Non-file archive member")
                            payload = archive.extractfile(member).read()
                        else:
                            payload = relative_file(args.source_root, sources[image_id]).read_bytes()
                    else:
                        payload = relative_file(root, image["package_path"]).read_bytes()
                    if len(payload) != image["bytes"] or hashlib.sha256(payload).hexdigest() != image["sha256"]:
                        raise ValueError("Image integrity mismatch")
                except (OSError, KeyError, ValueError) as error:
                    failures.append({"image_id": image_id, "error_type": type(error).__name__})
    finally:
        if archive is not None:
            archive.close()
    print(json.dumps({"questions_checked": len(selected), "unique_images_checked": len(checked), "failed_images": len(failures), "failures": failures[:20], "model_calls": 0}, ensure_ascii=False, indent=2))
    raise SystemExit(1 if failures else 0)


if __name__ == "__main__":
    main()