import ssl


def server_context_modern() -> ssl.SSLContext:
    """Return an SSL context following the Mozilla recommendations.
    TLS configuration follows the best-practice guidelines specified here:
    https://wiki.mozilla.org/Security/Server_Side_TLS
    Modern guidelines are followed.
    """
    context = ssl.SSLContext(ssl.PROTOCOL_TLS)  # pylint: disable=no-member

    context.options |= (
        ssl.OP_NO_SSLv2
        | ssl.OP_NO_SSLv3
        | ssl.OP_NO_TLSv1
        | ssl.OP_NO_TLSv1_1
        | ssl.OP_CIPHER_SERVER_PREFERENCE
    )
    if hasattr(ssl, "OP_NO_COMPRESSION"):
        context.options |= ssl.OP_NO_COMPRESSION

    context.set_ciphers(
        "ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:"
        "ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:"
        "ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:"
        "ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA384:"
        "ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256"
    )

    return context