Check whether WPML is active for current site in a Multisite environment

wpml_helper.php

<?php
/**
 * Check whether WPML is active for current site. Checking for the availability of the SitePress class is not enough,
 * because the plugin can be deactivated for a certain site. Also, this behavior is not consistent when switching blogs.
 * 
 * How *NOT* to do it: 
 * - `class_exists( 'SitePress' )`
 * - `defined('ICL_LANGUAGE_CODE')`
 * - ...
 */
function my_prefix_wpml_is_active(): bool {
	if ( ! class_exists( 'SitePress' ) ) {
		return false;
	}

	if ( ! function_exists( 'wpml_is_setup_complete' ) ) {
		return false;
	}

	if ( ! wpml_is_setup_complete() ) {
		return false;
	}

	return true !== (bool) get_option( '_wpml_inactive', false );
}