<?php
function proxifyCSS($css, $baseURL) {
return preg_replace_callback(
'/url\((.*?)\)/i',
function($matches) use ($baseURL) {
$url = $matches[1];
//Remove any surrounding single or double quotes from the URL so it can be passed to rel2abs - the quotes are optional in CSS
//Assume that if there is a leading quote then there should be a trailing quote, so just use trim() to remove them
if (strpos($url, "'") === 0) {
$url = trim($url, "'");
}
if (strpos($url, "\"") === 0) {
$url = trim($url, "\"");
}
if (stripos($url, "data:") === 0) return "url(" . $url . ")"; //The URL isn't an HTTP URL but is actual binary data. Don't proxify it.
return "url(" . PROXY_PREFIX . rel2abs($url, $baseURL) . ")";
},
$css);
}