import time
import logging
from typing import Coroutine, Union

from aiohttp.web import middleware, HTTPFound, Response, Request
from aiohttp import BasicAuth, hdrs
from aiohttp_session import get_session

log = logging.getLogger(__name__)

def _do_basic_auth_check(request: Request) -> Union[None, bool]:
    if "download_" not in request.match_info.route.name:
        return

    auth = None
    auth_header = request.headers.get(hdrs.AUTHORIZATION)
    if auth_header is not None:
        try:
            auth = BasicAuth.decode(auth_header=auth_header)
        except ValueError:
            pass

    if auth is None:
        try:
            auth = BasicAuth.from_url(request.url)
        except ValueError:
            pass

    if not auth:
        return Response(
            body=b"",
            status=401,
            reason="UNAUTHORIZED",
            headers={hdrs.WWW_AUTHENTICATE: 'Basic realm=""'},
        )

    if auth.login is None or auth.password is None:
        return

    if (
        auth.login != request.app["username"]
        or auth.password != request.app["password"]
    ):
        return

    return True

async def _do_cookies_auth_check(request: Request) -> Union[None, bool]:
    session = await get_session(request)
    if not session.get("logged_in", False):
        return

    session["last_at"] = time.time()
    return True

def middleware_factory() -> Coroutine:
    @middleware
    async def factory(request: Request, handler: Coroutine) -> Response:
        if request.app["is_authenticated"] and str(request.rel_url.path) not in [
            "/login",
            "/logout",
            "/favicon.ico",
        ]:
            url = request.app.router["login_page"].url_for()
            if str(request.rel_url) != "/":
                url = url.with_query(redirect_to=str(request.rel_url))

            basic_auth_check_resp = _do_basic_auth_check(request)

            if basic_auth_check_resp is True:
                return await handler(request)

            cookies_auth_check_resp = await _do_cookies_auth_check(request)

            if cookies_auth_check_resp is not None:
                return await handler(request)

            if isinstance(basic_auth_check_resp, Response):
                return basic_auth_check_resp

            return HTTPFound(url)

        return await handler(request)

    return factory