src/util/Date.php
public static function adjust($hour, $ampm) {
        $hour = (int)$hour;
        $ampm = strtolower($ampm);

        switch ($ampm) {
            case 'am':
                if ($hour == 12) {
                    $hour = 0;
                }
                break;
            case 'pm':
                if ($hour < 12) {
                    $hour += 12;
                }
                break;
        }

        return sprintf('%02d', $hour);
    }
public static function adjust($hour, $ampm) {
        $hour = (int)$hour;
        $ampm = strtolower($ampm);

        switch ($ampm) {
            case 'am':
                if ($hour == 12) {
                    $hour = 0;
                }
                break;
            case 'pm':
                if ($hour < 12) {
                    $hour += 12;
                }
                break;
        }

        return sprintf('%02d', $hour);
    }
Adjusts a non-24-hour number into a 24-hour number.

$hour = Date::adjust(3, 'pm'); // 15

@param   integer $hour hour to adjust
@param   string $ampm AM or PM
@return  string