#!/usr/bin/env python3
"""Fetch the hash-pinned non-V8 PDFium dependency for Linux or Windows x64."""
from pathlib import Path
import argparse
import hashlib
import json
import platform
import tarfile
import tempfile
import urllib.request

root = Path(__file__).resolve().parent.parent
lock = json.loads((root / 'cmake/pdfium.lock.json').read_text())
host = {'Linux': 'linux-x64', 'Windows': 'windows-x64'}.get(platform.system())
parser = argparse.ArgumentParser(description=__doc__)
parser.add_argument('--platform', choices=['linux-x64', 'windows-x64'], default=host)
parser.add_argument('--destination', type=Path)
args = parser.parse_args()
if args.platform is None or (args.platform == host and platform.machine() not in ('x86_64', 'AMD64')):
    raise SystemExit('A supported x64 platform is required; specify --platform for a cross-platform download.')
prefix = 'windowsX64' if args.platform == 'windows-x64' else 'linuxX64'
destination = args.destination or root / '.deps' / ('pdfium' if args.platform == host else 'pdfium-' + args.platform.split('-')[0])
with tempfile.TemporaryDirectory(prefix='docview-pdfium-') as temporary:
    archive = Path(temporary) / 'pdfium.tgz'
    urllib.request.urlretrieve(lock[prefix + 'Archive'], archive)
    if hashlib.sha256(archive.read_bytes()).hexdigest() != lock[prefix + 'Sha256']:
        raise SystemExit('PDFium archive hash mismatch; dependency not installed.')
    destination.mkdir(parents=True, exist_ok=True)
    with tarfile.open(archive) as bundle:
        bundle.extractall(destination, filter='data')
print(f'Installed pinned PDFium {lock["version"]} in {destination}')