Question

my query is about either creating a regex to capture:

1. 0 or More Subcategories
2. 0 or 1 Paging index
3. 0 or 1 Product Id

This would be done easily by reading everything as a single parameter and this parameter passed to php, however it would imply tons of code and a performance hit whereas htaccess+regex will do this with a single line of code.

Example:

catalog/
Show all products starting from page 0

catalog/dolls/barbie/malibu/
display all malibu barbie dolls starting from page 0

catalog/dolls/gijoe/p_5/id_99
display product id_99. However the page and categories are maintained to be displayed as navigational links.

catalog/dolls/p_3
catalog/dolls/barbie/id_456

RewriteRule ^catalog/(([^/:*?"<>|\r\n]*/)*)(id-([0-9]{1,4}+))*$ catalog.php?category=$1&id=$3

Ive tried with a url like catalog/doll/barbie/id-1234/ like this; however capturing $1 would yield doll/barbie/id-1234/ and stuff like id-1234/id-345/id-145/ would be ‘valid’ returning 145 hence hurting seo placement with duplicate pages, this regex dont even deal with paging… I use RegexBuddy3 (very useful, a MUST buy) but apache+httacess don’t behave 100% the same when dealing with über long expressions.

Answer 1

The easiest would be to pass the id of both the category and the product in the URL
You can make the URL look like this
catalog/dolls-12/ – You are now looking in the catalogue at the category id 12
catalog/dolls/barbie/malibu-33/ – You are now looking in the catalogue at the category id 33
catalog/dolls/barbie/malibu-33/barbie-450 – You are now looking in the catalogue at the category id 33 and at the product 450

This should be all done with 3 rules in htaccess. If you receive a link that looks like
catalogue/(.*)-number/(.*)-number you are looking at a product inside a category.
catalogue/(.*)-number then you are looking at a category
catalogue/ – you are looking at the entire catalogue.

You do not need to capture everything, just the numbers, those will already tell you where you are.