import os
from pathlib import Path
import shutil
import tempfile
import urllib.request
import zipfile

name = os.environ["APP_NAME"]
version = os.environ["APP_VERSION"]
plain_version = version.removeprefix("v")
url = f"https://github.com/storytold/{name}/releases/download/{version}/{name}-web-{plain_version}.zip"
with tempfile.TemporaryDirectory() as tmp:
    archive = Path(tmp) / "release.zip"
    urllib.request.urlretrieve(url, archive)
    unpacked = Path(tmp) / "unpacked"
    with zipfile.ZipFile(archive) as bundle:
        for member in bundle.infolist():
            path = Path(member.filename)
            if path.is_absolute() or ".." in path.parts or (member.external_attr >> 16) & 0o170000 == 0o120000:
                raise ValueError(f"unsafe archive entry: {path}")
        bundle.extractall(unpacked)
    roots = [path.parent for path in unpacked.glob("*/index.html")]
    if (unpacked / "index.html").exists():
        roots = [unpacked]
    if len(roots) != 1:
        raise ValueError("expected exactly one web root")
    target = Path("/srv/web")
    target.mkdir(parents=True)
    for source in roots[0].iterdir():
        destination = target / source.name
        if source.is_dir():
            shutil.copytree(source, destination)
        else:
            shutil.copy2(source, destination)