"""Check every downloaded file against the sha256 Hugging Face records for it (LFS files) at the pinned revision.
  usage: v2_sha.py <repo_id> <revision> <local_dir> [workers]"""
import hashlib, os, sys
from multiprocessing import Pool
from huggingface_hub import HfApi
repo, rev, local = sys.argv[1:4]; nw = int(sys.argv[4]) if len(sys.argv) > 4 else 32
def sha(p):
    h = hashlib.sha256()
    with open(p, "rb") as f:
        for b in iter(lambda: f.read(1 << 24), b""): h.update(b)
    return p, h.hexdigest(), os.path.getsize(p)
if __name__ == "__main__":
    info = HfApi().dataset_info(repo, revision=rev, files_metadata=True)
    want = {s.rfilename: (s.lfs.sha256 if s.lfs else None, s.size) for s in info.siblings}
    files = [f for f in want if want[f][0]]
    missing = [f for f in files if not os.path.exists(f"{local}/{f}")]
    print(f"{len(want)} files at {rev}, {len(files)} LFS; missing locally {missing}", flush=True)
    bad = []
    with Pool(nw) as pool:
        for n, (p, h, sz) in enumerate(pool.imap_unordered(sha, [f"{local}/{f}" for f in files if f not in missing]), 1):
            f = os.path.relpath(p, local)
            if h != want[f][0] or sz != want[f][1]: bad.append(f)
            if n % 32 == 0: print(f"  {n}/{len(files)}", flush=True)
    print(f"sha256+size mismatches: {len(bad)} {bad}\n{'ALL FILES MATCH' if not bad and not missing else '*** MISMATCH ***'}")