parsing multiple lists in bbcode? - php

Question

Hi all I have a very simple bbcode parsing system, it is currently having problems with lists within lists.
My code:
$find = array(
'/\[list\](.*?)\[\/list\]/is',
'/\[\*\](.*?)(\n|\r\n?)/is',
'/\[ul\](.*?)\[\/ul\]/is',
'/\[li\](.*?)\[\/li\]/is'
);
$replace = array(
'<ul>$1</ul>',
'<li>$1</li>',
'<ul>$1</ul>',
'<li>$1</li>'
);
$body = preg_replace($find, $replace, $body);
The problem is when you have another list inside the li tags it then completely fails to parse, screenshot showing:
This is how it should look:
I know my code is probably too simple for it but how do i adjust it so it can parse a list within a list item?

Answer 1

Rather than using Regular Expressions you have a couple of options..
Use PHP's BBCode Parsing extension
Do a much simpler replacement, ie. straight up replace [ul] with <ul> etc.
I'm not saying it can't be done with Regex, just that it's not the simplest option.
Here's a still-regex based replacement:
$body = '[ul][li]test[/li][li]test[/li][li]test[ul][li]lol[/li][/ul][/li][li]hehe[/li][/ul]';
$find = array(
'/\[(\/?)list\]/i',
'/\[\*\](.*?)(\n|\r\n?)/i',
'/\[(\/?)ul\]/i',
'/\[(\/?)li\]/i'
);
$replace = array(
'<$1ul>',
'<li>$1</li>',
'<$1ul>',
'<$1li>'
);
$body = preg_replace($find, $replace, $body);