# common/private_files/helpers.py
from django.urls import reverse
from django.core import signing


def build_private_url(app_label: str, model_name: str, pk: int | str, field_name: str, *, sign: bool = True) -> str:
    params = f"?app={app_label}&model={model_name}&pk={pk}&field={field_name}"
    
    if sign:
        token = signing.dumps(
            {"app": app_label, "model": model_name, "pk": pk, "field": field_name},
            salt="private-files",
            compress=True,
        )
        params += f"&token={token}"
    return reverse("private_file_download") + params