Modifying WP URL handing code?

Question

I am trying to use mod_rewrite and modify WordPress' URL handling to allow for passing variables to PHP from the URL while maintaining "pretty permalink" functionality. (on WP 3.2.1)

Something like this:

http:/epiclasers.com/hello-world (normal with permalinks set to /%postname%)

http:/epiclasers.com/state/hello-world (WP should display the same hello-world post as above, but also would pass the state string to PHP as a variable)

http:/epiclasers.com/state/city/hello-world (WP should display the hello-world post, but would pass the state and city strings to PHP as variables)

I added the following mod_rewrite directives to my .htaccess file:

RewriteRule ^(\w+)/(\w+)/ /index.php?state=$1&city=$2 [L]
RewriteRule ^(\w+)/ /index.php?state=$1 [L]

which kind of works. The variables are being passed, and PHP can grab them with:

$state = $_GET['state'];
$city = $_GET['city'];

The problem is that WP is getting confused by the variables in the URL and isn't outputting the correct template file. URL's like these:

http://epiclasers.com/arizona/phoenix/
http:/epiclasers.com/arizona/phoenix/hello-world
http://epiclasers.com/arizona/

are bringing up the 404 page not found template.

How do I modify the WP URL handling code to ignore the /state and /city parts of the URL without also breaking URLs like:

http:/epiclasers.com/category/category1
http:/epiclasers.com/tag/tag1
http:/epiclasers.com/category/category2/subcategory

etc.

Thanks,
Devin

Answer 1

I ended up solving this with a little bit of code (in the form of a plugin):

if(isset($_GET['state']) OR isset($_GET['city'])) {
$url = explode("/", $_SERVER['REQUEST_URI']);
$url = end($url);
$_SERVER['REQUEST_URI'] = "/" . $url;
}

This code in essence removes the "/arizona/" or "/arizona/phoenix/" from the REQUEST_URI global variable and replaces it with "/", which then forces WP to serve up the front page template using index.php. Fixed!

Perhaps a few of you can vote this answer up for me. :)