get_noptin_action_url( string $action, string $value = false, bool $empty = false )

function get_noptin_action_url( $action, $value = false, $empty = false ) {
	global $wp_rewrite;

	$permalink = get_option( 'permalink_structure' );

	// Ugly urls
	if ( empty( $permalink ) ) {
		return add_query_arg(
			array(
				'noptin_newsletter'  => $action,
				'nv'  => $value,
				'nte' => $empty,
			),
			get_home_url()
		);
	}

	// Pretty permalinks.
	$path = $wp_rewrite->root . "noptin_newsletter/$action";
	$url  = get_home_url( null, $path );

	if ( function_exists( 'PLL' ) ) {
		$url = PLL()->links_model->add_language_to_link( $url, PLL()->curlang );
	}

	return add_query_arg(
		array(
			'nv'  => $value,
			'nte' => $empty,
		),
		$url
	);

}