#!/usr/bin/env python3
# Copyright 2023 The Chromium Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

import argparse
import json
import os
import urllib.request

_GIT_HOST = 'https://chromium.googlesource.com/chromium/src.git'


def _get_last_commit(commit_url):
  """Returns the last commit of build/fuchsia.
  The approach is not very ideal since we may want to ignore unrelated
  changes like the linux_internal.sdk.sha1 file.
  """
  content = urllib.request.urlopen(commit_url).read().decode('utf-8')
  # Remove the leading json safety prefix.
  assert content.startswith(")]}'")
  return json.loads(content[4:])['log'][0]['commit']


def _do_latest(commit_url):
  print(_get_last_commit(commit_url))


def _get_download_url(sha, archive_url):
  """Returns the manifest for the following download procedure."""
  partial_manifest = {
    'url': [archive_url.format(sha)],
    'ext': '.tar.gz',
  }
  print(json.dumps(partial_manifest))


def main(path):
  # Getting the last commit of the subfolder is now disallowed by
  # chromium.googlesource.com/chromium/ without authentication. We retrieve
  # the log from the root of the repository instead.
  # See crbug.com/517362685.
  # TODO(crbug.com/517362685): Revert to "+log/refs/heads/main/{path}"
  # once the authentication requirement is removed.
  commit_url = f'{_GIT_HOST}/+log?n=1&format=json'
  archive_url = f'{_GIT_HOST}/+archive/{{}}/{path}.tar.gz'

  ap = argparse.ArgumentParser()
  sub = ap.add_subparsers()

  latest = sub.add_parser("latest")
  latest.set_defaults(func=lambda: _do_latest(commit_url))

  download = sub.add_parser("get_url")
  download.set_defaults(
    func=lambda: _get_download_url(
      os.environ.get('_3PP_VERSION', _get_last_commit(commit_url)), archive_url
    )
  )

  opts = ap.parse_args()
  opts.func()