Get the previous working day

Getting yesterday's date using the PHP date() function is simple:

<?php
$lastWorkingDay = date( "d", strtotime("-1 day") );
?>

The problem began when the past day was Friday of the previous week.

To deal with this, just get the current day of the week, then switch between the collected value to go back the necessary number of days:

<?php

//get weekday, from 0 (sunday) to 6 (saturday)
$currentWeekDay = date( "w" );

switch ($currentWeekDay) {
  case "1": {  // monday
    $lastWorkingDay = date("d", strtotime("-3 day"));
    break;
  }
  case "0": {  // sunday
    $lastWorkingDay = date("d", strtotime("-2 day"));
    break;
  }
  default: {  //all other days
    $lastWorkingDay = date("d", strtotime("-1 day"));
    break;
  }
}
?>