from django.urls import include, path, re_path
from django.utils.module_loading import import_string


def default_urlpatterns(provider):
    package = provider.get_package()

    try:
        login_view = import_string(package + ".views.login")
    except ImportError:
        raise ImportError(
            "The login view for the '{id}' provider is lacking from the "
            "'views' module of its app.\n"
            "You may want to add:\n"
            "from allauth_cas.views import CASLoginView\n\n"
            "login = CASLoginView.adapter_view(<LocalCASAdapter>)".format(
                id=provider.id
            )
        )

    try:
        callback_view = import_string(package + ".views.callback")
    except ImportError:
        raise ImportError(
            "The callback view for the '{id}' provider is lacking from the "
            "'views' module of its app.\n"
            "You may want to add:\n"
            "from allauth_cas.views import CASCallbackView\n\n"
            "callback = CASCallbackView.adapter_view(<LocalCASAdapter>)".format(
                id=provider.id
            )
        )

    try:
        logout_view = import_string(package + ".views.logout")
    except ImportError:
        logout_view = None

    urlpatterns = [
        path("login/", login_view, name=provider.id + "_login"),
        path("login/callback/", callback_view, name=provider.id + "_callback"),
    ]

    if logout_view is not None:
        urlpatterns += [
            path("logout/", logout_view, name=provider.id + "_logout"),
        ]

    return [re_path("^" + provider.get_slug() + "/", include(urlpatterns))]