<?php

namespace Safe;

use DateInterval;
use DateTime;
use DateTimeInterface;
use DateTimeZone;
use Safe\Exceptions\DatetimeException;

/**
* This class is used to implement a safe version of the DatetimeImmutable class.
* While it technically overloads \DateTimeImmutable for typehint compatibility,
* it is actually used as a wrapper of \DateTimeImmutable, mostly to be able to overwrite functions like getTimestamp() while still being able to edit milliseconds via setTime().
*/
class DateTimeImmutable extends \DateTimeImmutable
{
/**
* @var \DateTimeImmutable
*/
private $innerDateTime;

/**
* DateTimeImmutable constructor.
* @param string $time
* @param DateTimeZone|null $timezone
* @throws \Exception
*/
public function __construct($time = 'now', $timezone = null)
{
parent::__construct($time, $timezone);
$this->innerDateTime = new parent($time, $timezone);
}

//switch between regular datetime and safe version
public static function createFromRegular(\DateTimeImmutable $datetime): self
{
$safeDatetime = new self($datetime->format('Y-m-d H:i:s.u'), $datetime->getTimezone()); //we need to also update the wrapper to not break the operators '<' and '>'
$safeDatetime->innerDateTime = $datetime; //to make sure we don't lose information because of the format().
return $safeDatetime;
}

//usefull if you need to switch back to regular DateTimeImmutable (for example when using DatePeriod)
public function getInnerDateTime(): \DateTimeImmutable
{
return $this->innerDateTime;
}

/////////////////////////////////////////////////////////////////////////////
// overload functions with false errors

/**
* @param string $format
* @param string $time
* @param DateTimeZone|null $timezone
* @throws DatetimeException
*/
public static function createFromFormat($format, $time, $timezone = null): self
{
$datetime = parent::createFromFormat($format, $time, $timezone);
if ($datetime === false) {
throw DatetimeException::createFromPhpError();
}
return self::createFromRegular($datetime);
}

/**
* @param string $format
* @return string
* @throws DatetimeException
*/
public function format($format): string
{
/** @var string|false $result */
$result = $this->innerDateTime->format($format);
if ($result === false) {
throw DatetimeException::createFromPhpError();
}
return $result;
}

/**
* @param DateTimeInterface $datetime2
* @param bool $absolute
* @return DateInterval
* @throws DatetimeException
*/
public function diff($datetime2, $absolute = false): DateInterval
{
/** @var \DateInterval|false $result */
$result = $this->innerDateTime->diff($datetime2, $absolute);
if ($result === false) {
throw DatetimeException::createFromPhpError();
}
return $result;
}

/**
* @param string $modify
* @return DateTimeImmutable
* @throws DatetimeException
*/
public function modify($modify): self
{
/** @var \DateTimeImmutable|false $result */
$result = $this->innerDateTime->modify($modify);
if ($result === false) {
throw DatetimeException::createFromPhpError();
}
return self::createFromRegular($result); //we have to recreate a safe datetime because modify create a new instance of \DateTimeImmutable
}

/**
* @param int $year
* @param int $month
* @param int $day
* @return DateTimeImmutable
* @throws DatetimeException
*/
public function setDate($year, $month, $day): self
{
/** @var \DateTimeImmutable|false $result */
$result = $this->innerDateTime->setDate($year, $month, $day);
if ($result === false) {
throw DatetimeException::createFromPhpError();
}
return self::createFromRegular($result); //we have to recreate a safe datetime because modify create a new instance of \DateTimeImmutable
}

/**
* @param int $year
* @param int $week
* @param int $day
* @return DateTimeImmutable
* @throws DatetimeException
*/
public function setISODate($year, $week, $day = 1): self
{
/** @var \DateTimeImmutable|false $result */
$result = $this->innerDateTime->setISODate($year, $week, $day);
if ($result === false) {
throw DatetimeException::createFromPhpError();
}
return self::createFromRegular($result); //we have to recreate a safe datetime because modify create a new instance of \DateTimeImmutable
}

/**
* @param int $hour
* @param int $minute
* @param int $second
* @param int $microseconds
* @return DateTimeImmutable
* @throws DatetimeException
*/
public function setTime($hour, $minute, $second = 0, $microseconds = 0): self
{
/** @var \DateTimeImmutable|false $result */
$result = $this->innerDateTime->setTime($hour, $minute, $second, $microseconds);
if ($result === false) {
throw DatetimeException::createFromPhpError();
}
return self::createFromRegular($result);
}

/**
* @param int $unixtimestamp
* @return DateTimeImmutable
* @throws DatetimeException
*/
public function setTimestamp($unixtimestamp): self
{
/** @var \DateTimeImmutable|false $result */
$result = $this->innerDateTime->setTimestamp($unixtimestamp);
if ($result === false) {
throw DatetimeException::createFromPhpError();
}
return self::createFromRegular($result);
}

/**
* @param DateTimeZone $timezone
* @return DateTimeImmutable
* @throws DatetimeException
*/
public function setTimezone($timezone): self
{
/** @var \DateTimeImmutable|false $result */
$result = $this->innerDateTime->setTimezone($timezone);
if ($result === false) {
throw DatetimeException::createFromPhpError();
}
return self::createFromRegular($result);
}

/**
* @param DateInterval $interval
* @return DateTimeImmutable
* @throws DatetimeException
*/
public function sub($interval): self
{
/** @var \DateTimeImmutable|false $result */
$result = $this->innerDateTime->sub($interval);
if ($result === false) {
throw DatetimeException::createFromPhpError();
}
return self::createFromRegular($result);
}

/**
* @throws DatetimeException
*/
public function getOffset(): int
{
/** @var int|false $result */
$result = $this->innerDateTime->getOffset();
if ($result === false) {
throw DatetimeException::createFromPhpError();
}
return $result;
}

//////////////////////////////////////////////////////////////////////////////////////////
//overload getters to use the inner datetime immutable instead of itself

/**
* @param DateInterval $interval
* @return DateTimeImmutable
*/
public function add($interval): self
{
return self::createFromRegular($this->innerDateTime->add($interval));
}

/**
* @param DateTime $dateTime
* @return DateTimeImmutable
*/
public static function createFromMutable($dateTime): self
{
return self::createFromRegular(parent::createFromMutable($dateTime));
}

/**
* @param mixed[] $array
* @return DateTimeImmutable
*/
public static function __set_state($array): self
{
return self::createFromRegular(parent::__set_state($array));
}

public function getTimezone(): DateTimeZone
{
return $this->innerDateTime->getTimezone();
}

public function getTimestamp(): int
{
return $this->innerDateTime->getTimestamp();
}
}