/**
* Obtains an instance of {@code ZonedDateTime} from an {@code Instant}.
* <p>
* This creates a zoned date-time with the same instant as that specified.
* Calling {@link #toInstant()} will return an instant equal to the one used here.
* <p>
* Converting an instant to a zoned date-time is simple as there is only one valid
* offset for each instant.
*
* @param Instant $instant the instant to create the date-time from, not null
* @param ZoneId $zone the time-zone, not null
* @return ZonedDateTime the zoned date-time, not null
* @throws DateTimeException if the result exceeds the supported range
*/
public static function ofInstant(Instant $instant, ZoneId $zone)
{
return self::create($instant->getEpochSecond(), $instant->getNano(), $zone);
}
/**
* Gets the previous transition before the specified instant.
* <p>
* This returns details of the previous transition after the specified instant.
* For example, if the instant represents a point where "summer" daylight saving time
* applies, then the method will return the transition from the previous "winter" time.
*
* @param Instant|null $instant the instant to get the previous transition after, not null, but null
* may be ignored if the rules have a single offset for all instants
* @return ZoneOffsetTransition the previous transition after the specified instant, null if this is before the first transition
*/
public function previousTransition($instant)
{
if (empty($this->savingsInstantTransitions)) {
return null;
}
$epochSec = $instant->getEpochSecond();
if ($instant->getNano() > 0 && $epochSec < Long::MAX_VALUE) {
$epochSec += 1;
// allow rest of method to only use seconds
}
// check if using last rules
$lastHistoric = $this->savingsInstantTransitions[count($this->savingsInstantTransitions) - 1];
if (!empty($this->lastRules) && $epochSec > $lastHistoric) {
// search year the instant is in
$lastHistoricOffset = $this->wallOffsets[count($this->wallOffsets) - 1];
$year = $this->findYear($epochSec, $lastHistoricOffset);
$transArray = $this->findTransitionArray($year);
for ($i = count($transArray) - 1; $i >= 0; $i--) {
if ($epochSec > $transArray[$i]->toEpochSecond()) {
return $transArray[$i];
}
}
// use last from preceding year
$lastHistoricYear = $this->findYear($lastHistoric, $lastHistoricOffset);
if (--$year > $lastHistoricYear) {
$transArray = $this->findTransitionArray($year);
return $transArray[count($transArray) - 1];
}
// drop through
}
// using historic rules
$index = Math::binarySearch($this->savingsInstantTransitions, $epochSec);
if ($index < 0) {
$index = -$index - 1;
}
if ($index <= 0) {
return null;
}
return ZoneOffsetTransition::ofEpoch($this->savingsInstantTransitions[$index - 1], $this->wallOffsets[$index - 1], $this->wallOffsets[$index]);
}
private function check(Instant $instant, $epochSecs, $nos)
{
$this->assertEquals($instant->getEpochSecond(), $epochSecs);
$this->assertEquals($instant->getNano(), $nos);
$this->assertEquals($instant, $instant);
}
