Losing the original URL when using add_rewrite_rule

Question

I'm attempting to implement a rewrite rule so I can introduce a variable into my CPT's single page template. Basically I'm trying to include 'all' between my CPT's slug name of work and the category in the URL:

http://localhost/work/all/corporate/cognitive-puzzles/

The original URL should of course work as well:

http://localhost/work/corporate/cognitive-puzzles/

Here's what I have for my rewrite:

function wire_alternate_pdp_url() {
    global $wp;
    $wp->add_query_var('mode');
    add_rewrite_rule('work/all/([^/]*)/([^/]*)/?', 'index.php?pagename=$matches[2]&mode=all', 'top');
}

This almost works but for two issues. First being, the URL in my browser switches back to the form with the missing all/ path. Second and more importantly, I get nothing for a mode within my single-project.php:

<?php 
    $mode = get_query_var('mode');
    echo $mode;
?>

This prints out nothing.

Any ideas on what I might be missing here? I feel I'm close but something isn't quite right.

Thanks in advance!

edit: forgot to mention, I'm running 3.6.1

Answer 1

wow, after more banging of my head against the wall, it took this:

add_rewrite_rule('work/all/([^/]*)/([^/]*)/?', 'index.php?post_type=project&name=$matches[2]&mode=all', 'top');

Two things actually, I had to include a post_type=project part as well as change pagename to name. If I remove either one, I get my previous results.

I am not sure why this set of values works when other examples didn't have this, but glad it works :)