PHP - Shortening Url

So a friend is making a URL shortening site, well hes already made it and got it working but he wanted me to do some work on it and then he showed me the code and I just felt like shooting myself in the head for offering to help. Its an absolute mess the are tonnes of folders with tonnes of files in each with more folders in them that contain code that could easily be functions. He said he added on top of some other code he got from somewhere.

So I'm thinking of just starting again. Everything that needs to be done I can do except for the URL shrinking. How do I make a redirect without actually creating the file. So say www.clickme.com/randomnumbers but that random numbers isn't a file and just comes up with a page with adverts then a link to continue on.

I created a functional class that shortens or expands the URL using google's shortening service. The class works but i feel like i can optimize it more but i don't know really how because i'm new in using classes.
here is the code
Code: [Select]
define('GOOGLE_API_KEY', 'khjdaskjfsjkdhgfbsdhgsj');
define('GOOGLE_ENDPOINT', 'https://www.googleapis.com/urlshortener/v1');

class shortenGoogle {
function shortenUrl($longUrl){
// initialize the cURL connection
$ch = curl_init(sprintf('%s/url?key=%s', GOOGLE_ENDPOINT, GOOGLE_API_KEY));

// tell cURL to return the data rather than outputting it
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
// create the data to be encoded into JSON
$requestData = array(
'longUrl' => $longUrl
);

// change the request type to POST
curl_setopt($ch, CURLOPT_POST, true);

// set the form content type for JSON data
curl_setopt($ch, CURLOPT_HTTPHEADER, array('Content-type: application/json'));

// set the post body to encoded JSON data
curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($requestData));

// perform the request
$result = curl_exec($ch);
curl_close($ch);

// decode and return the JSON response
return json_decode($result, true);
}

function expandUrl($shortUrl){
// initialize the cURL connection
$ch = curl_init(sprintf('%s/url?key=%s&shortUrl='.$shortUrl.'', GOOGLE_ENDPOINT, GOOGLE_API_KEY));

// tell cURL to return the data rather than outputting it
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

// tell cURL to ignore the SSL certificate in case it expires
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);

// perform the request
$result = curl_exec($ch);
curl_close($ch);

// decode and return the JSON response
return json_decode($result, true);
}
}
$short = new shortenGoogle;
$url = $short->shortenUrl('http://www.google.com/');
print_r($url);