<?php
add_action('init', 'projects_cpt');
function projects_cpt() {

$args = array(
    'hierarchical' => true,
    'rewrite' => array('slug' => 'projects'),
    'show_in_nav_menus' => true,
    'labels' => $labels
);

register_taxonomy('projectscategory', 'projects', $args);

unset($labels);
unset($args);


 $labels = array(
    'name' => 'Projects',
    'singular_name' => 'Project',
    'add_new' => 'Add New',
    'add_new_item' => 'Add New Project',
    'edit_item' => 'Edit Project',
    'new_item' => 'New Project',
    'all_items' => 'All Projects',
    'view_item' => 'View Project',
    'search_items' => 'Search Projects',
    'not_found' => 'No projects found',
    'not_found_in_trash' => 'No projects found in Trash',
    'parent_item_colon' => '',
    'menu_name' => 'Projects'
);
$args = array(
    'labels' => $labels,
    'public' => true,
    'publicly_queryable' => true,
    'show_ui' => true,
    'show_in_menu' => true,
    'query_var' => true,
    'taxonomies' => array('projectstype' ),
    'rewrite' => array('slug' => 'projects/%projectscategory%', 'with_front' => false),
    //Adding custom rewrite tag
    'capability_type' => 'post',
    'has_archive' => 'projectsarchives',
    'hierarchical' => false,
    'menu_position' => null,
    'supports' => array('title', 'editor', 'author', 'thumbnail', 'excerpt'),
);
register_post_type('projects', $args);

$labels = array(
    'name' => 'Projects Categories',
    'singular_name' => 'Projects',
    'search_items' => 'Search Projects Categories',
    'all_items' => 'All Projects Categories',
    'parent_item' => 'Parent Project Category',
    'parent_item_colon' => 'Parent Project Category:',
    'edit_item' => 'Edit Project Category',
    'update_item' => 'Update Project Category',
    'add_new_item' => 'Add New Project Category',
    'new_item_name' => 'New Project Category',
);


}

?>

<?php
add_filter('post_type_link', 'projectcategory_permalink_structure', 10, 4);
function projectcategory_permalink_structure($post_link, $post, $leavename,
$sample) {
if (false !== strpos($post_link, '%projectscategory%')) {
    $projectscategory_type_term = get_the_terms($post->ID, 'projectscategory');
    if (!empty($projectscategory_type_term))
        $post_link = str_replace('%projectscategory%', array_pop($projectscategory_type_term)->
        slug, $post_link);
    else
        $post_link = str_replace('%projectscategory%', 'uncategorized', $post_link);
}
return $post_link;
}

?>