add_action( 'init', 'models_post_type' );
function models_post_type() {
  register_post_type( 'models',
    array(
      'labels' => array(
        'name' => __( 'Models' ),
        'singular_name' => __( 'Models' ),
      ),
      'public' => true,
      'has_archive' => 'model_category',
	  'menu_icon' => 'dashicons-id',
	  'rewrite' => array('slug' => 'categories/%model_category%','with_front' => false),
	  'supports' => array('title','editor','thumbnail','comments'),
	  /* "cptp_permalink_structure" => "/categories/%model_category%/%postname%"*/
    )
  );
}



add_action( 'init', 'model_taxonomies', 0 );
function model_taxonomies(){
	register_taxonomy(
		'model_category',
		'models',
		array(
			'hierarchical' => true,
			'label' => __('Model category'),
			'show_ui'                    => true,
			'show_admin_column'          => true,
			'query_var' => true,
			'rewrite' => array(
	            'slug'                  => 'categories',
	            'with_front'            => true,
	            'hierarchical'          => false
	        ),
		)
	);
}


add_filter( 'post_type_link', 'wpa_show_permalinks', 1, 2 );

	function wpa_show_permalinks( $post_link, $post ){
		$list_posts = array(
			'categories' => 'model_category',
		);

		foreach ($list_posts as $cpt => $tax){
			if ( is_object( $post ) && $post->post_type == $cpt ){
				$terms = wp_get_object_terms( $post->ID, $tax );
				$term_slug = $terms ? $terms[0]->slug : 'no-cat';

				return str_replace( '%'.$tax.'%' ,$term_slug, $post_link );
			}
		}
		return $post_link;
	}