Make EDD work with NGINX

gistfile1.php

<?php 
/**
 * Make sure EDD doesn't trip over the NGINX values of global server settings and returns the proper current page URL.
 *
 * @param string $url The current page URL
 * @return string The fixed current page URL.
 */
function yst_fix_edd_current_page_url( $url ) {
	if ( is_front_page() ) :
		$page_url = home_url();
	else :
		$page_url = 'http';

		if ( ( isset( $_SERVER["HTTPS"] ) && $_SERVER["HTTPS"] == "on" ) || intval( $_SERVER["SERVER_PORT"] ) == 443 )
			$page_url .= "s";

		$page_url .= "://" . $_SERVER["SERVER_NAME"] . $_SERVER["REQUEST_URI"];
	endif;

	return $page_url;
}

add_filter( 'edd_get_current_page_url', 'yst_fix_edd_current_page_url', 10, 1 );