read_limit

$total_free_reads = 3;
$cookie_name = 'article_reads';

function check_update_cookie() {
	global $cookie_name;

	if( is_single() ){
		$expiry = strtotime('+1 month');

		if( ! isset($_COOKIE[$cookie_name]) ){
			setcookie($cookie_name, serialize([]), $expiry, '/');
		}else{
			$article_ids = unserialize($_COOKIE[$cookie_name]);

			//reading new article? add its ID to the cookie
			if( ! in_array( get_the_id(), $article_ids ) ){
				$article_ids[] = get_the_id();
			}

			setcookie($cookie_name, serialize($article_ids),  $expiry, '/');
		}

	}
};

function check_remove_block() {
	global $total_free_reads, $cookie_name;

	//if cookie is not set or limit not reached, deactivate plugin block
	if( ! isset($_COOKIE[$cookie_name]) || sizeof(unserialize($_COOKIE[$cookie_name])) < ($total_free_reads-1) ){
		//unregister content filter
		remove_filter('the_content', array('ARU_ReadMoreLogin\ContentLoader', 'FilterContent'), 99);

		//remove the dead shortcode from content view
		add_shortcode('rml_read_more', function( $atts, $content = "" ){
			return '';
		});
	}
}

//only run for guest users
if( ! is_user_logged_in() ){
	add_action('template_redirect', 'check_update_cookie');
	add_action('init', 'check_remove_block');
}

//remove cookie if user is logged in
if( is_user_logged_in() && isset($_COOKIE[$cookie_name]) ){
	setcookie($cookie_name, '', (time() - 3600), '/');
}