Wordpress: CPT active menu class fix

cpt-active-menu-clas-fix.php

<?php
/**
 * cusom post type active menu item fix
 * not 100% working, it does remove the class, 
 * but if you are using custom page template to display post type, the active class insertion might not work
 *
 * @autor : ajith
 * @url : http://trytoinnovate.com
 * @referance : https://gist.github.com/AlphaBlossom/ae2f676d4763d1f1b3a2
 *
 */

add_filter( 'nav_menu_css_class', 'cpt_active_class_fix', 10, 3 );
function cpt_active_class_fix( $classes, $item, $args ) {

    global $post;
    $current_post_type = get_post_type_object(get_post_type($post->ID)); //getting current post type
    $current_post_type_slug = $current_post_type->rewrite[slug]; //getting current page slug
    $menu_slug = strtolower(trim($item->url)); // Getting the URL of the menu item

    //check if its custom post type and not a regular post
    if( ( $current_post_type != 'post' ) && ( is_home() || is_single() || is_archive() || is_category() || is_tag() || is_author() ) )  {
        //getting home/blog page id
        $blog_page_id = intval( get_option('page_for_posts') );

        if( $blog_page_id != 0 && $item->object_id == $blog_page_id ) {

            //remove the active class
            unset( $classes[array_search( 'active', $classes )] );
        }
    }

    // If the menu item URL contains the current post types slug add the current-menu-item class
    if (strpos($menu_slug,$current_post_type_slug) !== false) {

        $classes[] = 'active';
    }

    return $classes;
}

?>