#!/usr/bin/env python3
import http.client
import json
import re
import sys

from typing import Dict, Tuple


def parse_location(fname: str) -> Dict[str, str]:
    pattern = r"CrashPlanSmb_(?P<ver>[0-9.]+)_(?P<build>[0-9]+)_Linux.tgz"
    regex = re.compile(pattern)
    match = regex.match(fname)
    if match:
        return match.groupdict()
    else:
        raise ValueError("regex match failed")


def get_upstream_ver():
    # get upstream version from parsing the redirect URL from:
    # download.crashplan.com/installs/agent/latest-smb-linux.tgz
    conn = http.client.HTTPSConnection("download.crashplan.com")
    conn.request("HEAD", "/installs/agent/latest-smb-linux.tgz")
    resp = conn.getresponse()
    loc = resp.headers.get("location")
    fname = loc.rsplit("/", 1)[-1]
    print(f"Parsing upstream filename {fname}")
    info = parse_location(fname)
    return info["ver"]


def get_aur_ver() -> str:
    # get aur version from aur rpc:
    # aur.archlinux.org/rpc/?v=5&type=info&arg[]=crashplan-pro
    conn = http.client.HTTPSConnection("aur.archlinux.org")
    conn.request("GET", "/rpc/?v=5&type=info&arg[]=crashplan-pro")
    resp = conn.getresponse().read()
    respj = json.loads(resp)
    data = respj["results"][0]
    ver, _ = data["Version"].rsplit("-", 2)
    return ver


def parse_ver(v: str) -> Tuple[int, ...]:
    return tuple(int(cmp) for cmp in v.split("."))


def newer(other: str, base: str) -> bool:
    return parse_ver(other) > parse_ver(base)


def main():
    aur_ver = get_aur_ver()
    upstream_ver = get_upstream_ver()

    if newer(upstream_ver, aur_ver):
        print(f"{upstream_ver} > {aur_ver}")
        sys.exit(0)

    print(f"{upstream_ver} <= {aur_ver}")
    sys.exit(1)


if __name__ == "__main__":
    main()