class UnauthorisedAccessError(Exception):
    """ User does not have access priviledges """


@bp.app_errorhandler(UnauthorisedAccessError)
def handle_login_error(e):
    """Redirect to the login page when LoginError is raised."""

    flash("You do not have sufficient access rights to perform this action",
          'error')
    return redirect(url_for('auth.login'))


def check_user_group(required_groups):
    """
    Traverse list of required access groups to check for one or more matches
    """
    access = [current_user.has_access(PermissionGroups.query.filter_by(
                                                             group_name=group
                                                             ).first())
              for group in required_groups]
    if not any(access):
        raise UnauthorisedAccessError


def group_required(*groups):
    """
    Decorate a function to require the user to have at least one of the groups.
    """

    def decorator(func):
        @wraps(func)
        def check_auth(*args, **kwargs):
            check_user_group(*groups)

            return func(*args, **kwargs)

        return check_auth

    return decorator