htaccess - writing a rewrite rule for php

Question

I am struggling to work out how to write a rewrite rule to work for multiple fields for a product catalog that i'm currently building.

my files are stored in a folder on url.com/catalog - and then i want to structure url's like the below;

url.com/catalog/CATEGORY
url.com/catalog/CATEGORY/SUB-CATEGORY
url.com/catalog/CATEGORY/SUB-CATEGORY/PRODUCT

Where the Category, Sub-Category or Product is the URI from the database they are stored. This will then send to;

page.php?cat=CATURI&subcat=SUBCATURI&product=PRODUCTURI

I have used multiple threads and tutorials and come up with the below;

RewriteRule ^(.*)/(.*)/(.*)/(.*)$ catalog/page.php?cat=$2&subcat=$3&product=$4

which doesn't work at all how i need it to as the sub cat and product don't always have to pass.

Any suggestions for this?

Answer 1

You can divide your url into elements : catalog, category, sub-category, product. Using this function:

function get_path_elements() {
          if (!isset($_SERVER['PATH_INFO'])) { return null; }
          $path_info = $_SERVER['PATH_INFO'];
          $path_elements = explode('/', $path_info);
          array_shift($path_elements);
          return $path_elements; 
}

The work after is quite similar to what you have done.