Plugin breaks on SSL

On Line 1059 of infusionsoft.php, there is a call to bloginfo() that outputs the admin-ajax link (used when setting up the form to tap into).

However, in SSL-protected environments, this appears to fail. A simple is_ssl() call (or something a bit more complex, to accommodate load balancers/nginx) would fix this issue.

This:
var mysack = new sack("<?php bloginfo( 'wpurl' ); ?>/wp-admin/admin-ajax.php" );

Could become something like:

<?php $domain = get_bloginfo('wpurl');
  if(is_ssl || (isset($_SERVER['HTTP_X_FORWARDED_PROTO']) && $_SERVER['HTTP_X_FORWARDED_PROTO'] == 'https')) {
  $domain = str_replace('http://', 'https://', $domain);
}
?>
var mysack = new sack("<?php echo $domain; ?>/wp-admin/admin-ajax.php");

https://wordpress.org/plugins/infusionsoft/