#! /usr/bin/env nix-shell
#! nix-shell -i python3 -p python3Packages.packaging python3Packages.debian common-updater-scripts

import base64
import textwrap
import os
from urllib import request

from collections import OrderedDict
from debian.deb822 import Packages
from debian.debian_support import Version
from os.path import abspath, dirname

PIN_PATH = dirname(abspath(__file__)) + '/default.nix'

def packages():
    packages_url = 'https://packages.microsoft.com/repos/edge/dists/stable/main/binary-amd64/Packages'
    handle = request.urlopen(packages_url)
    return handle


def latest_packages(packages: bytes):
    latest_packages: OrderedDict[str, Packages] = {}
    for package in Packages.iter_paragraphs(packages, use_apt_pkg=False):
        name: str = package['Package']
        if not name.startswith('microsoft-edge-stable'):
            continue
        channel = name.replace('microsoft-edge-', '')
        if channel not in latest_packages:
            latest_packages[channel] = package
        else:
            old_package = latest_packages[channel]
            if old_package.get_version() < package.get_version():  # type: ignore
                latest_packages[channel] = package
    return OrderedDict(sorted(latest_packages.items(), key=lambda x:x[0]))


def write_expression():
    latest = latest_packages(packages())
    version = Version.re_valid_version.match(latest['stable']['Version']).group('upstream_version')
    os.system(f'update-source-version microsoft-edge "{version}"')


write_expression()