bp_email_get_unsubscribe_link( array $args )

function bp_email_get_unsubscribe_link( $args ) {
	$emails = bp_email_get_unsubscribe_type_schema();

	if ( empty( $args['notification_type'] ) || ! array_key_exists( $args['notification_type'], $emails ) ) {
		return wp_login_url();
	}

	$email_type  = $args['notification_type'];
	$redirect_to = ! empty( $args['redirect_to'] ) ? $args['redirect_to'] : site_url();
	$user_id     = (int) $args['user_id'];

	// Bail out if the activity type is not un-unsubscribable.
	if ( empty( $emails[ $email_type ]['unsubscribe'] ) ) {
		return '';
	}

	$link = add_query_arg(
		array(
			'action' => 'unsubscribe',
			'nh'     => hash_hmac( 'sha1', "{$email_type}:{$user_id}", bp_email_get_salt() ),
			'nt'     => $args['notification_type'],
			'uid'    => $user_id,
		),
		$redirect_to
	);

	/**
	 * Filters the unsubscribe link.
	 *
	 * @since BuddyPress 2.7.0
	 */
	return apply_filters( 'bp_email_get_link', $link, $redirect_to, $args );
}