Get working days in a month

working-days.php

<?php

function get_working_days($year, $month, $last_day = null) {
  $total_month_days = date('t', strtotime("$year-$month-01"));

  if ($last_day) {
    $total_month_days = $last_day;
  }

  $working_days;
  $sundays;

  for ($day = 1; $day <= $total_month_days; $day++) {
    $dayOfWeek = date('N', strtotime("$year-$month-$day"));

    if ($dayOfWeek == 7) {
      $sundays++;
    } else {
      $working_days++;
    }
  }
  return array($working_days, $sundays);
}