Permalink rewrites for post type + 2 (hierarchical) taxonomy

/* ==========================================================================
   Post Types
   ========================================================================== */

add_action( 'init', 'my_custom_post_auto' );
function my_custom_post_auto() {
      $labels = array(
        'name'               => _x( 'Auto', 'post type general name' ),
        'singular_name'      => _x( 'auto', 'post type singular name' ),
        'add_new'            => _x( 'Voeg toe', 'auto' ),
        'add_new_item'       => __( 'Voeg nieuwe auto toe' ),
        'edit_item'          => __( 'Edit auto' ),
        'new_item'           => __( 'Nieuwe auto' ),
        'all_items'          => __( 'Alle autos' ),
        'view_item'          => __( 'Bekijk auto' ),
        'search_items'       => __( 'Zoek auto' ),
        'not_found'          => __( 'Geen autos gevonden' ),
        'not_found_in_trash' => __( 'Geen autos gevonden' ),
        'parent_item_colon'  => '',
        'menu_name'          => 'Autos'
      );
      $args = array(
        'labels'        => $labels,
        'description'   => '',
        'public'        => true,
        'menu_position' => 5,
        'supports'      => array( 'title', 'editor', 'thumbnail'),
        'has_archive'   => 'autos',
        'rewrite'       => array('slug' => 'merk/%auto-merk%/%auto-bouwjaar%' ),
      );
      register_post_type( 'auto', $args );
}


/* ==========================================================================
   Taxonomies
   ========================================================================== */

/* Auto Merk taxonomy */
function auto_merk_taxonomy() {
  $labels = array(
    'name'              => __('Automerken'),
    'singular_name'     => __('Automerk'),
    'search_items'      => __('Zoek automerken'),
    'all_items'         => __('Alle automerken'),
    'parent_item'       => __('Hoofdautomerk'),
    'parent_item_colon' => __('Hoofdautomerk:'),
    'edit_item'         => __('Bewerk automerk'),
    'update_item'       => __('Werk automerk bij'),
    'add_new_item'      => __('Voeg nieuw automerk toe'),
    'new_item_name'     => __('Nieuw automerk'),
    'menu_name'         => __('Automerken')
  );
  $args = array(
    'labels'            => $labels,
    'hierarchical'      => true,
    'query_var'         => true,
    'rewrite'           => array('slug' => 'merk', 'hierarchical' => true)
  );
  register_taxonomy('auto-merk', 'auto', $args);
}
add_action( 'init', 'auto_merk_taxonomy' );


/* Auto Bouwjaar taxonomy */
function auto_bouwjaar_taxonomy() {
  $labels = array(
    'name'              => __('Bouwjaren'),
    'singular_name'     => __('Bouwjaar'),
    'search_items'      => __('Zoek bouwjaren'),
    'all_items'         => __('Alle bouwjaren'),
    'parent_item'       => __('Hoofdbouwjaar'),
    'parent_item_colon' => __('Hoofdbouwjaar:'),
    'edit_item'         => __('Bewerk bouwjaar'),
    'update_item'       => __('Werk bouwjaar bij'),
    'add_new_item'      => __('Voeg nieuw bouwjaar toe'),
    'new_item_name'     => __('Nieuw bouwjaar'),
    'menu_name'         => __('Bouwjaren')
  );
  $args = array(
    'labels'            => $labels,
    'hierarchical'      => true,
    'query_var'         => true,
    'rewrite'           => array('slug' => 'merk', 'hierarchical' => true)
  );
  register_taxonomy('auto-bouwjaar', 'auto', $args);
}
add_action( 'init', 'auto_bouwjaar_taxonomy' );



/* ==========================================================================
   Permalink Structure
   ========================================================================== */

function filter_post_type_link($link, $post) {
    if ($post->post_type != 'auto')
      return $link;

    if ($cats = get_the_terms($post->ID, 'auto-merk')) { // return both parent and child terms alphabetically
        $link = str_replace('%auto-merk%', get_taxonomy_parents(array_pop($cats)->term_id, 'auto-merk', false, '/', true), $link);
        //$family_id = print_taxonomy_ranks( get_the_terms($post->ID, 'auto-merk') ); // get only child term id
        //$link = str_replace('%auto-merk%', get_taxonomy_parents($family_id, 'auto-merk', false, '/', true), $link);
    }
    return $link;
}
add_filter('post_type_link', 'filter_post_type_link', 10, 2);


/*
 * rank hierarchical taxonomy terms:
 * http://wordpress.stackexchange.com/questions/37285/custom-taxonomy-get-the-terms-listing-in-order-of-parent-child
 */
function print_taxonomy_ranks($terms = '' ){
    // check input
    if ( empty( $terms ) || is_wp_error( $terms ) || ! is_array( $terms ) )
        return;
    // set id variables to 0 for easy check
    $order_id = $family_id = $subfamily_id = 0;

    // get order
    foreach ( $terms as $term ) {
        if ( $order_id || $term->parent )
            continue;
        $order_id  = $term->term_id;
        $order     = $term->name;
    }
    // get family
    foreach ( $terms as $term ) {
        if ( $family_id || $order_id != $term->parent )
            continue;
        $family_id = $term->term_id;
        $family    = $term->name;
    }
    // get subfamily
    foreach ( $terms as $term ) {
        if ( $subfamily_id || $family_id != $term->parent )
            continue;
        $subfamily_id = $term->term_id;
        $subfamily    = $term->name;
    }
    // output
    return $family_id;
}

/*
 * Get taxonomy parents:
 * http://wordpress.stackexchange.com/questions/101316/custom-post-type-with-two-hierarchical-custom-taxonomies-strategy-to-generate-b
 */
function get_taxonomy_parents($id, $taxonomy, $link = false, $nicename = false, $visited = array()) {
    // removed $seperator="/" after $link, otherwise there was a double slash before the post name in the link
    $chain = '';
    $parent = &get_term($id, $taxonomy);

    if (is_wp_error($parent)) {
        return $parent;
    }

    if ($nicename)
        $name = $parent -> slug;
    else
        $name = $parent -> name;

    if ($parent -> parent && ($parent -> parent != $parent -> term_id) && !in_array($parent -> parent, array($visited)) ) {
        $visited[] = $parent -> parent;
        $chain .= get_taxonomy_parents($parent -> parent, $taxonomy, $link, $nicename, $visited); //removed $seperator after $link
        $chain .= "/"; //add a / after every category
    }

    if ($link) {
        // nothing, can't get this working :(
    } else
        $chain .= $name; //don't need the . $separator anymore
    return $chain;
}

function filter_post_type_link_due($link, $post) {
    if ($post->post_type != 'auto')
        return $link;

    if ($cats = get_the_terms($post->ID, 'auto-bouwjaar')) {
        $link = str_replace('%auto-bouwjaar%', get_taxonomy_parents(array_pop($cats)->term_id, 'auto-bouwjaar', false, '/', true), $link);
    }
    return $link;
}
add_filter('post_type_link', 'filter_post_type_link_due', 10, 2);



/* ==========================================================================
   Rewrite Rules
   ========================================================================== */

add_filter('rewrite_rules_array', 'mmp_rewrite_rules');
function mmp_rewrite_rules($rules) {

    //TIPOLOGIA
    $tipologie = get_terms('auto-merk', array(
        'hide_empty' => false
    ));

    foreach ($tipologie as $tipologia) {
        $slugs_tipologie [] = $tipologia->slug;
    }

    $num_tipologie = count($slugs_tipologie);
    $regex_tipologia = '';
    if( $num_tipologie > 0) {
        for( $i=0; $i < $num_tipologie-1; $i++ ) {
            $regex_tipologia .= $slugs_tipologie[$i] .'|';
        }
        $regex_tipologia .= array_pop($slugs_tipologie);
    }

    $ee1 = merk."/($regex_tipologia)/(.+)/(.+)/(.+)/(.+)/?$";
    $ee2 = merk."/($regex_tipologia)/?$";
    $ee3 = merk."/($regex_tipologia)/(.+)/?$";
    $ee4 = merk."/(.+)/?$";

    $newRules  = array();
    $newRules[$ee1] = 'index.php?auto=$matches[5]';
    $newRules[$ee2] = 'index.php?auto-merk=$matches[1]';
    $newRules[$ee3] = 'index.php?auto-merk=$matches[1]&auto-bouwjaar=$matches[2]';
    $newRules[$ee4] = 'index.php?auto-bouwjaar=$matches[1]';
    return array_merge($newRules, $rules);
}