"""Fetch immutable, human-written RU/EN held-out text for CPT evaluation.

Universal Dependencies test splits are independent of Maven's CPT source list.
Only sentence text from CoNLL-U comments is retained. Re-running is deterministic.
"""
from __future__ import annotations

import hashlib
import json
import subprocess
import tempfile
from pathlib import Path

OUT = Path(__file__).resolve().parent / "data" / "eval"
SOURCES = {
    "ru": {
        "commit": "0f34b7362ac3c3facd1d6ff4b876d241bb15793e",
        "repo": "UD_Russian-GSD",
        "file": "ru_gsd-ud-test.conllu",
    },
    "en": {
        "commit": "4a4d77f599ea53cc405f85d0cec4b2f14f81d42b",
        "repo": "UD_English-EWT",
        "file": "en_ewt-ud-test.conllu",
    },
}


def fetch(repo: str, commit: str, filename: str) -> bytes:
    """Fetch one pinned Git object; git transport is more reliable than raw CDN."""
    with tempfile.TemporaryDirectory(prefix="maven-eval-") as tmp:
        target = Path(tmp) / "repo"
        subprocess.run(
            ["git", "clone", "--quiet", "--filter=blob:none", "--no-checkout",
             f"https://github.com/UniversalDependencies/{repo}.git", str(target)],
            check=True,
        )
        return subprocess.run(
            ["git", "-C", str(target), "show", f"{commit}:{filename}"],
            check=True, capture_output=True,
        ).stdout


def sentences(raw: str) -> list[str]:
    return [line[9:].strip() for line in raw.splitlines() if line.startswith("# text = ")]


def main() -> None:
    OUT.mkdir(parents=True, exist_ok=True)
    manifest = {"schema_version": 1, "license": "UD treebanks; see source repositories"}
    for lang, source in SOURCES.items():
        url = (f"https://raw.githubusercontent.com/UniversalDependencies/"
               f"{source['repo']}/{source['commit']}/{source['file']}")
        raw = fetch(source["repo"], source["commit"], source["file"])
        lines = sentences(raw.decode("utf-8"))
        if len(lines) < 500:
            raise SystemExit(f"unexpectedly small {lang} evaluation set: {len(lines)}")
        output = OUT / f"{lang}_ud_test.txt"
        output.write_text("\n".join(lines) + "\n", encoding="utf-8")
        manifest[lang] = {
            **source, "url": url, "sentences": len(lines),
            "raw_sha256": hashlib.sha256(raw).hexdigest(),
            "text_sha256": hashlib.sha256(output.read_bytes()).hexdigest(),
        }
    (OUT / "manifest.json").write_text(
        json.dumps(manifest, indent=2, ensure_ascii=False) + "\n", encoding="utf-8")
    print(json.dumps(manifest, indent=2, ensure_ascii=False))


if __name__ == "__main__":
    main()