from collections.abc import Callable

from django.http import HttpRequest, HttpResponse


class ScriptPrefixPathMiddleware:
    """Re-add the ``FORCE_SCRIPT_NAME`` prefix to ``request.path`` under ASGI.

    Django's ASGI handler sets ``request.path = scope["path"]`` verbatim (see
    ``django/core/handlers/asgi.py``). When the reverse proxy strips the
    script-name prefix (e.g. ``/scores``) before forwarding, ``request.path`` —
    and therefore ``get_full_path()`` — loses the prefix, even though
    ``reverse()`` still prepends it via the script prefix. The result is the
    admin login form posting to ``/admin/login/?next=/admin/`` instead of
    ``/scores/admin/login/?next=/scores/admin/``.

    URL resolution is unaffected (it uses ``path_info``), so we only need to
    realign the path-based URLs with the reverse()-based ones. The check is
    idempotent: if the proxy already forwards the prefix, this is a no-op.
    """

    def __init__(self, get_response: Callable[[HttpRequest], HttpResponse]) -> None:
        self.get_response = get_response

    def __call__(self, request: HttpRequest) -> HttpResponse:
        script_name = request.META.get("SCRIPT_NAME", "").rstrip("/")
        if script_name and not request.path.startswith(f"{script_name}/"):
            request.path = f"{script_name}{request.path}"
        return self.get_response(request)