code optimized

 	/**

--- ./apps/dav/lib/CalDAV/Schedule/IMipPlugin.php	2022-07-04 12:41:03.228533600 +0530

+++ ./apps/dav/lib/CalDAV/Schedule/IMipPlugin-new.php	2022-07-04 12:31:43.728533600 +0530

@@ -419,23 +419,34 @@

+++ ./apps/dav/lib/CalDAV/Schedule/IMipPlugin-new.php	2022-07-04 14:42:56.208533600 +0530

@@ -419,23 +419,33 @@

 	 * @param VEvent $vevent

 	 */

 	private function generateWhenString(IL10N $l10n, VEvent $vevent) {

-			$isFloating = $vevent->DTSTART->isFloating();

-			$dtend = clone $vevent->DTSTART;

+		$lastmodified=0;

+		$selectedEvent = $vevent;

+		foreach( $vevent as $currentevent){

+			$dtstamp= $currentevent->{'LAST-MODIFIED'};

+			$dtstampTime = strtotime($dtstamp);

+			if($dtstampTime>$lastmodified){

+				$lastmodified=$dtstampTime;

+				$dtStartFinal= $currentevent->DTSTART;

+				$dtEndtFinal= $currentevent->DTEND;

+				$durationFinal= $currentevent->DURATION;

+				$selectedEvent = $currentevent;

+			}

+		}

+		$dtstart = $dtStartFinal;

+		if (isset($dtEndtFinal)) {

+			$dtend = $dtEndtFinal;

+		} elseif (isset($durationFinal)) {

+			$isFloating = $dtStartFinal->isFloating();

+			$dtend = clone $dtStartFinal;

+		$dtstart = $selectedEvent->DTSTART;

+		if (isset($selectedEvent->DTEND)) {

+			$dtend = $selectedEvent->DTEND;

+		} elseif (isset($selectedEvent->DURATION)) {

+			$isFloating = $selectedEvent->DTSTART->isFloating();

+			$dtend = clone $selectedEvent->DTSTART;

 			$endDateTime = $dtend->getDateTime();

-			$endDateTime = $endDateTime->add(DateTimeParser::parse($vevent->DURATION->getValue()));

+			$endDateTime = $endDateTime->add(DateTimeParser::parse($durationFinal->getValue()));

+			$endDateTime = $endDateTime->add(DateTimeParser::parse($selectedEvent->DURATION->getValue()));

 			$dtend->setDateTime($endDateTime, $isFloating);

-		} elseif (!$vevent->DTSTART->hasTime()) {

-			$isFloating = $vevent->DTSTART->isFloating();

-			$dtend = clone $vevent->DTSTART;

+		} elseif (!$dtStartFinal->hasTime()) {

+			$isFloating = $dtStartFinal->isFloating();

+			$dtend = clone $dtStartFinal;

+		} elseif (!$selectedEvent->DTSTART->hasTime()) {

+			$isFloating = $selectedEvent->DTSTART->isFloating();

+			$dtend = clone $selectedEvent->DTSTART;

 			$endDateTime = $dtend->getDateTime();

 			$endDateTime = $endDateTime->modify('+1 day');

 			$dtend->setDateTime($endDateTime, $isFloating);

 		} else {

-			$dtend = clone $vevent->DTSTART;

+			$dtend = clone $dtStartFinal;

+			$dtend = clone $selectedEvent->DTSTART;

 		}

 		$isAllDay = $dtstart instanceof Property\ICalendar\Date;