gistfile1.txt

class pisol_custom_code_20260119{
	static $instance = null;

	static function get_instance() {
		if ( null === self::$instance ) {
			self::$instance = new self();
		}
		return self::$instance;
	}

	function __construct() {
		add_filter('pisol_dtt_date_sort', [$this, 'dates'], PHP_INT_MAX);
	}

	function dates($dates) {
		$dates = self::removeNonWorkingDays($dates);
		return $dates;
	}

	static function removeNonWorkingDays($dates){
        $type = pi_dtt_delivery_type::getType();
        $var_name = 'pi_'.$type.'_days';
        $allowed_days = pisol_dtt_get_setting($var_name, array());  
        if(empty($allowed_days)) return $dates;
        
        foreach($dates as $key => $date){
            $day_of_week = date('w', strtotime($date));
            if(!in_array((string)$day_of_week, $allowed_days)){
                unset($dates[$key]);
            }
        }
        return $dates;
    }
}

pisol_custom_code_20260119::get_instance();