Php add 5 working days to current date excluding weekends (sat-sun) and excluding (multiple) holidays

Question

For delivery of our webshop, we need to calculate 5 working days from the current date in php.

Our working days are from monday to friday and we have several closing day

Answer 1

A function based on Tinh Dang's answer:

function getFutureBusinessDay($num_business_days, $today_ymd = null, $holiday_dates_ymd = []) {
    $num_business_days = min($num_business_days, 1000);
    $business_day_count = 0;
    $current_timestamp = empty($today_ymd) ? time() : strtotime($today_ymd);
    while ($business_day_count < $num_business_days) {
        $next1WD = strtotime('+1 weekday', $current_timestamp);
        $next1WDDate = date('Y-m-d', $next1WD);        
        if (!in_array($next1WDDate, $holiday_dates_ymd)) {
            $business_day_count++;
        }
        $current_timestamp = $next1WD;
    }
    return date('Y-m-d', $current_timestamp);
}

I made it limit the loop to 1000 business days. There could be no limit if desired.