bbcode url, check http://

[Dragen]

Hi, I'm writing a very simple bbcode script. The problem I've got is with urls. I can easily turn this into a link:

[url=somelink.com]this is a link[/url]

But I'm having difficulty in insuring the the link starts with http(s)://

 

Here's what I'm using:

<?php
function replace($text){
	$patterns[] = '(\[b\](.+?)\[\/b\])';
	$patterns[] = '(\[i\](.+?)\[\/i\])';
	$patterns[] = '(\[sup\](.+?)\[\/sup\])';
	$patterns[] = '(\[url\]([ a-zA-Z0-9\:\/\-\?\&\.\=\_\~\#]*)\[\/url\])';
	$patterns[] = '(\[url\=([ a-zA-Z0-9\:\/\-\?\&\.\=\_\~\#]*)\](.+?)\[/url\])';

	$reps[] = '<strong>$1</strong>';
	$reps[] = '<em>$1</em>';
	$reps[] = '<sup>$1</sup>';
	$reps[] = '<a href="$1" target="_blank" title="$1">$1</a>';
	$reps[] = '<a href="$1" target="_blank" title="$2">$2</a>';

	return preg_replace($patterns, $reps, nl2br($text));
?>

I know there must be a simple way of checking and if needs be, adding the http://.

Maybe I'm just too tired and being stupid.

[Dragen]

okay, I've come up with a solution that works to a degree, but I'm not too keen on:

	function replace($text){
	$patterns[] = '(\[url\](https?://)?([ a-zA-Z0-9\:\/\-\?\&\.\=\_\~\#]*)\[\/url\])';
	$patterns[] = '(\[url\=(https?://)?([ a-zA-Z0-9\:\/\-\?\&\.\=\_\~\#]*)\](.+?)\[/url\])';

	$reps[] = '<a href="http://$2" target="_blank" title="$2">$2</a>';
	$reps[] = '<a href="http://$2" target="_blank" title="$3">$3</a>';

	return preg_replace($patterns, $reps, nl2br($text));
}

I just remove the http(s):// from the url (if it exists), then add http:// to the url, so url's which didn't have it now do.

The problem is, if the url started with https I've now replaced it with http, which may cause problems.

 

I'd prefer a method of checking if it has http(s)://. If so then leave it in the url, if not add http://.