Blank page returns on woocommerce registration redirect filtered

I am adding the registration form on the product page for those who are logged out. I have filtered the redirection but I get a blank page in return.

I am working on my modifications on my computer as localhost.

Could this be the reason why or is their something wrong with my code.

If anyone can help me, I would appreciate it very much.

Thank you.

if(!function_exists('product_registration_redirect')){
	/**
	 * Filters the registration form if the
	 * user registers on a single product page.
	 */
	function product_registration_redirect($redirect){
		global $post, $woocommerce;

		$page = (int) $_POST['redirect_after'];

		if( is_product() ){
			if(isset($page) && $page != ''){
				$redirect = esc_url( add_query_arg( 'action', 'registered', get_permalink($page) ) );
			}
			else{
				$redirect = esc_url( get_permalink( woocommerce_get_page_id('myaccount') ) );
			}
			return $redirect;
		}
	}
}
add_filter('woocommerce_registration_redirect', 'product_registration_redirect'); // Redirect back to the product page after registration on product page.

http://wordpress.org/plugins/woocommerce/