import posixpath


def safe_join(base: str, *paths: str) -> str:
    """
    A version of django.utils._os.safe_join for S3 paths.
    Joins one or more path components to the base path component
    intelligently. Returns a normalized version of the final path.
    The final path must be located inside of the base path component
    (otherwise a ValueError is raised).
    Paths outside the base path indicate a possible security
    sensitive operation.
    """
    base_path = base
    base_path = base_path.rstrip("/")
    paths = tuple(paths)

    final_path = base_path + "/"
    for path in paths:
        _final_path = posixpath.normpath(posixpath.join(final_path, path))
        # posixpath.normpath() strips the trailing /. Add it back.
        if path.endswith("/") or _final_path + "/" == final_path:
            _final_path += "/"
        final_path = _final_path
    if final_path == base_path:
        final_path += "/"

    # Ensure final_path starts with base_path and that the next character after
    # the base path is /.
    base_path_len = len(base_path)
    if not final_path.startswith(base_path) or final_path[base_path_len] != "/":
        raise ValueError(
            "the joined path is located outside of the base path" " component"
        )

    return final_path.lstrip("/")