url/httpUrl in bootstrapped file

[suntrop]

I included the PW index.php in a script file and need to return a full URL of pages (autocomplete Ajax response)

However, the file is located on another host and I get the wrong URL
ajax.example.com/public/search_autocomplete.php

I am wondering why ->url and ->httpUrl is /public/found/page/ or ajax.example.com/public/found/page/ instead of /found/page/ or example.com/found/page/ … and how to get the proper URL. Do I need to set the $config->httpHost again or something else?

<?php namespace ProcessWire; 
header('Access-Control-Allow-Origin: *'); 
error_reporting(-1);
include '../../../www/index.php';

$q = wire('sanitizer')->selectorValue( wire('input')->get('q') );
$results =  wire('pages')->find('title%=' . $q . ', template=basic-page, limit=10');

$array['query'] = $q;
foreach ($results as $result) {
	$array['suggestions'][] = ['value' => $result->title, 'data' => $result->url];
}

echo json_encode($array);