/**
* Simply takes an incoming UTC timestamp or DateTime object and does calculations on it based on the incoming parameters and returns the new timestamp or DateTime.
* @param int | DateTime $DateTime_or_timestamp DateTime object or Unix timestamp
* @param string $period a value to indicate what interval is being used in the calculation. The options are 'years', 'months', 'days', 'hours', 'minutes', 'seconds'. Defaults to years.
* @param integer $value What you want to increment the date by
* @param string $operand What operand you wish to use for the calculation
* @return mixed string|DateTime return whatever type came in.
*/
public static function calc_date($DateTime_or_timestamp, $period = 'years', $value = 1, $operand = '+')
{
if ($DateTime_or_timestamp instanceof DateTime) {
return EEH_DTT_Helper::_modify_datetime_object($DateTime_or_timestamp, $period, $value, $operand);
} else {
if (preg_match(EE_Datetime_Field::unix_timestamp_regex, $DateTime_or_timestamp)) {
return EEH_DTT_Helper::_modify_timestamp($DateTime_or_timestamp, $period, $value, $operand);
} else {
//error
return $DateTime_or_timestamp;
}
}
}
