Distinct Classes for WordPress Menu items with Last class

<?php

/**
 * Filters nav menu objects & items in your menus to add distinct custom classes to each item.
 * Identifies last menu object and adds custom class for last item.
 * @param object $objects An array of nav menu objects
 * @param object $args Nav menu object args
 * @return object $objects Amended array of nav menu objects with new class
 * Original code: http://pastebin.com/WMhBfFqR - does not identify child elements correctly
 * Working Solution Pastebin: http://pastebin.com/T0hr6sEx
 */

add_filter( 'wp_nav_menu_objects', 'vm_filter_menu_classes', 10, 2 );
function vm_filter_menu_classes( $objects, $args ) {

    if ( isset( $args->theme_location ) )
        if ( 'primary' !== $args->theme_location ) // Only apply the classes to the primary navigation menu
            return $objects;
    $navObjects = wp_get_nav_menu_object( 'main' ); // this is the custom menu name
    $objCount = $navObjects->count;
    $i=0;
    $navItems = wp_get_nav_menu_items( $navObjects ); //ref link: http://codex.wordpress.org/Function_Reference/wp_get_nav_menu_items
    $navParentsArray = array ();
    foreach($navItems as $navItem){
        $i++; // increment counter
        $itemID = $navItem->ID;
        $itemTitle = $navItem->post_title;
        $itemParent = $navItem->menu_item_parent;
        $itemObjectID = $navItem->object_id;
        $itemDB_ID = $navItem->db_id;
        $itemPostName = $navItem->post_name; // returns page/post ID
        if ( ( $itemParent == "0" )  ) {
            $n=0;
            $itemParents = $itemParents+1;
            $saveParent = $itemDB_ID;
            array_push($navParentsArray, $itemID);
            $objects[$i]->classes[] = 'vm-parent-item-' . $i; // Add distinct class to menu parent objects
            if ( $i == $objCount ) {
                $objects[$i]->classes[] = 'vm-last-menu-item'; // Add "last-menu-item" class to the last menu object
            }
        }
        if ( ( $itemParent <> "0" )  ) {
            $n=$n+1;
            $objects[$i]->classes[] = 'vm-parent-' . $saveParent . '-child-' . $n; // Add distinct class to menu parent objects
        }
    } // end foreach
    return $objects;
} // end vm_filter_menu_classes
?>