#!/usr/bin/env python3
"""Download, verify and load this DRBenchPro Docker archive (Python 3.10+)."""
import argparse
import hashlib
import json
from pathlib import Path
import re
import shutil
import subprocess
import sys
import urllib.parse
import urllib.request

REPO = 'zhuiluozhiji/DRBenchPro-runtime'
VERSION = '0.3.0-enwiki-20260701-v1-8733db7-linux-amd64'
IMAGE_ID = 'sha256:a5b1f5a2608cf8258a8ebc796f745d775c772d4bccc9faf0bf88410d95f20e37'
IMAGE_TAG = 'drbenchpro/standalone:0.3.0-enwiki-20260701-v1-8733db7'
BUFFER = 8 * 1024**2


def manifest(root):
    folder = root / 'images' / VERSION
    data = json.loads((folder / 'release.json').read_text())
    if data.get('version') != VERSION or data.get('image_id') != IMAGE_ID or data.get('image_tag') != IMAGE_TAG:
        raise ValueError('Release identity does not match this helper')
    if data.get('platform') != 'linux/amd64' or data.get('archive_format') != 'docker-save+gzip':
        raise ValueError('Unexpected platform or archive format')
    records = data['parts']
    if not records or len(records) > 1000:
        raise ValueError('Invalid part count')
    for i, item in enumerate(records):
        if item['filename'] != f'drbenchpro.tar.gz.part-{i:03d}':
            raise ValueError('Missing or unordered part in release manifest')
        if not re.fullmatch('[0-9a-f]{64}', item['sha256']):
            raise ValueError('Invalid SHA-256 in release manifest')
        if type(item['bytes']) is not int or not 0 < item['bytes'] <= data['part_size_bytes']:
            raise ValueError('Invalid part length')
        if i < len(records)-1 and item['bytes'] != data['part_size_bytes']:
            raise ValueError('Unexpected short part before final part')
    if sum(item['bytes'] for item in records) != data['archive_bytes']:
        raise ValueError('Archive size does not match part sizes')
    if not re.fullmatch('[0-9a-f]{64}', data['archive_sha256']):
        raise ValueError('Invalid complete archive SHA-256')
    return folder, data


def verify(root):
    folder, data = manifest(root)
    expected = {item['filename'] for item in data['parts']}
    actual = {p.name for p in folder.glob('drbenchpro.tar.gz.part-*')}
    if actual != expected:
        raise ValueError(f'Part set differs; missing={sorted(expected-actual)}, unexpected={sorted(actual-expected)}')
    sums = ''.join(f"{p['sha256']}  {p['filename']}\n" for p in data['parts'])
    if (folder / 'SHA256SUMS').read_text() != sums:
        raise ValueError('SHA256SUMS disagrees with release manifest')
    if (folder / 'ARCHIVE_SHA256').read_text().split() != [data['archive_sha256'], '-']:
        raise ValueError('ARCHIVE_SHA256 disagrees with release manifest')
    whole = hashlib.sha256()
    for i, item in enumerate(data['parts'], 1):
        path = folder / item['filename']
        if path.is_symlink() or path.stat().st_size != item['bytes']:
            raise ValueError('Incorrect part size or symlink: ' + item['filename'])
        digest = hashlib.sha256()
        with path.open('rb') as stream:
            while block := stream.read(BUFFER):
                digest.update(block)
                whole.update(block)
        if digest.hexdigest() != item['sha256']:
            raise ValueError('SHA-256 mismatch: ' + item['filename'])
        print(f"[{i}/{len(data['parts'])}] OK {item['filename']}", flush=True)
    if whole.hexdigest() != data['archive_sha256']:
        raise ValueError('Complete archive SHA-256 mismatch')
    print('Complete archive SHA-256 verified: ' + whole.hexdigest(), flush=True)
    return folder, data


def inspect_image(name):
    result = subprocess.run(['docker', 'image', 'inspect', name], text=True, capture_output=True)
    if result.returncode:
        return None
    values = json.loads(result.stdout)
    return values[0]


def load(root):
    if shutil.which('docker') is None:
        raise RuntimeError('Docker CLI is required')
    subprocess.run(['docker', 'info', '--format', '{{.DockerRootDir}}'], check=True)
    present = inspect_image(IMAGE_TAG)
    if present and present['Id'] != IMAGE_ID:
        raise RuntimeError('The release tag already points to a different local image; resolve the conflict first')
    folder, data = verify(root)
    print('Importing verified archive into Docker; allow space for the full image and extraction.', flush=True)
    proc = subprocess.Popen(['docker', 'image', 'load'], stdin=subprocess.PIPE)
    try:
        for item in data['parts']:
            with (folder / item['filename']).open('rb') as stream:
                while block := stream.read(BUFFER):
                    proc.stdin.write(block)
        proc.stdin.close()
        if proc.wait() != 0:
            raise RuntimeError('Docker image load failed')
    except BaseException:
        if not proc.stdin.closed:
            proc.stdin.close()
        proc.wait()
        raise
    loaded = inspect_image(IMAGE_ID)
    if not loaded or loaded['Id'] != IMAGE_ID or loaded['Os'] != 'linux' or loaded['Architecture'] != 'amd64':
        raise RuntimeError('Loaded image identity or platform differs')
    present = inspect_image(IMAGE_TAG)
    if present and present['Id'] != IMAGE_ID:
        raise RuntimeError('Local tag changed during import; refusing to overwrite it')
    if not present:
        subprocess.run(['docker', 'image', 'tag', IMAGE_ID, IMAGE_TAG], check=True)
    if inspect_image(IMAGE_TAG)['Id'] != IMAGE_ID:
        raise RuntimeError('Image tag verification failed')
    print('Ready: ' + IMAGE_TAG + '\n' + IMAGE_ID, flush=True)


def download(root, revision):
    if shutil.which('hf') is None:
        raise RuntimeError('Install the Hugging Face hf CLI before downloading')
    ref = urllib.parse.quote(revision, safe='')
    url = f'https://huggingface.co/api/datasets/{REPO}/revision/{ref}'
    with urllib.request.urlopen(url, timeout=60) as response:
        commit = json.load(response)['sha']
    if not re.fullmatch('[0-9a-f]{40}', commit):
        raise ValueError('Unexpected remote revision')
    url = f'https://huggingface.co/datasets/{REPO}/resolve/{commit}/images/{VERSION}/release.json'
    with urllib.request.urlopen(url, timeout=60) as response:
        release = json.load(response)
    if release.get('image_id') != IMAGE_ID:
        raise ValueError('Remote image differs from this helper')
    root.mkdir(parents=True, exist_ok=True)
    already = sum((root / 'images' / VERSION / p['filename']).stat().st_size for p in release['parts'] if (root / 'images' / VERSION / p['filename']).is_file())
    remaining = max(0, release['archive_bytes'] - already)
    print(f"Fixed revision: {commit}\nCompressed archive: {release['archive_bytes']:,} bytes in {len(release['parts'])} parts", flush=True)
    if shutil.disk_usage(root).free < remaining:
        raise RuntimeError('Insufficient download filesystem free space')
    subprocess.run(['hf', 'download', REPO, '--repo-type', 'dataset', '--revision', commit, '--local-dir', str(root), '--include', 'images/'+VERSION+'/*', '--include', 'scripts/*'], check=True)
    print('Download complete. Run verify.sh or load.sh before using the image.', flush=True)


def main():
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument('action', choices=['download', 'verify', 'load'])
    parser.add_argument('--directory', type=Path, default=Path(__file__).resolve().parent.parent)
    parser.add_argument('--revision', default='main', help='HF commit, tag or branch; resolved once before download')
    args = parser.parse_args()
    root = args.directory.resolve()
    if args.action == 'download':
        download(root, args.revision)
    elif args.action == 'verify':
        verify(root)
    else:
        load(root)


if __name__ == '__main__':
    try:
        main()
    except (OSError, ValueError, RuntimeError, KeyError, subprocess.CalledProcessError) as exc:
        print(f'Error: {exc}', file=sys.stderr)
        sys.exit(1)