ddd

	public function subscribe($product_id, $user) {
       $query =  $this->db->query("SELECT subscribes FROM " . DB_PREFIX . "product WHERE product_id = '" . (int)$product_id . "'");


       if ($query->num_rows && $query->row['subscribes'] != '' ) {

        $subscribes = json_decode($query->row['subscribes']);
        $user = json_decode($user);



        $key = array_search($user->email, array_column($subscribes, 'email'));


        if(false == $key) {
            return false;
        }

        array_push($subscribes, $user);

        $subscribes = json_encode($subscribes);

       } else {
           $user = json_decode($user);
           $subscribes = json_encode(array($user));
       }



        $this->db->query("UPDATE " . DB_PREFIX . "product SET subscribes = '$subscribes' WHERE product_id = '" . (int)$product_id . "'");
       return true;
    }