Wordpress responsive image proxy

imageProxy.php

<?php

	class ImageProxy {

		function __construct($request) {

			$this->sourceFolder = "/wp-content/uploads/";
			$this->path = dirname($request);
			$this->partialFileName = str_replace($this->path."/", "", $request);

			$this->serve($this->findImage());

		}

		private function getDirectoryListing() {

			$directoryListing = Array();

			if ($handle = opendir($this->sourceFolder.$this->path)) {

				while (false !== ($file = readdir($handle))) {

					if ($file === "." || $file === "..") continue;

					$directoryListing[] = $file;

				}

				closedir($handle);
			}

			return $directoryListing;

		}

		private function findImage() {

			$allImages = $this->getDirectoryListing($this->path);

			foreach ($allImages as $image) {

				if (false !== strpos($image, $this->partialFileName)) {

					return $this->path."/".$image;

				}

			}

			return false;

		}

		private function serve($path) {

			if (!$path) {

				header("HTTP/1.0 404 Not Found");

			} else {

				header("Content-Type: image/jpg");
				header("HTTP/1.1 301 Moved Permanently");
				header("Location: ".$this->sourceFolder.$path);

			}

			exit();

		}

	}

	if (isSet($_GET["path"])) {

		new ImageProxy($_GET["path"]);

	} else {

		header("HTTP/1.0 404 Not Found");
		echo "Path not set";

	}

?>