composer libs minor version updates

26 files changed, 227 insertions, 158 deletions

diff --git a/vendor/sabre/vobject/README.md b/vendor/sabre/vobject/README.md
index 5030cf276..659e3fa83 100644
--- a/vendor/sabre/vobject/README.md
+++ b/vendor/sabre/vobject/README.md
@@ -4,7 +4,7 @@ sabre/vobject
 The VObject library allows you to easily parse and manipulate [iCalendar](https://tools.ietf.org/html/rfc5545)
 and [vCard](https://tools.ietf.org/html/rfc6350) objects using PHP.
 
-The goal of the VObject library is to create a very complete library, with an easy to use API.
+The goal of the VObject library is to create a very complete library, with an easy-to-use API.
 
 
 Installation
diff --git a/vendor/sabre/vobject/lib/Cli.php b/vendor/sabre/vobject/lib/Cli.php
index 4984ac9b2..816e2cb31 100644
--- a/vendor/sabre/vobject/lib/Cli.php
+++ b/vendor/sabre/vobject/lib/Cli.php
@@ -453,8 +453,6 @@ HELP
      * Colorizes a file.
      *
      * @param Component $vObj
-     *
-     * @return int
      */
     protected function color($vObj)
     {
diff --git a/vendor/sabre/vobject/lib/Component.php b/vendor/sabre/vobject/lib/Component.php
index 07f6a627f..f33b628a7 100644
--- a/vendor/sabre/vobject/lib/Component.php
+++ b/vendor/sabre/vobject/lib/Component.php
@@ -339,6 +339,7 @@ class Component extends Node
      *
      * @return array
      */
+    #[\ReturnTypeWillChange]
     public function jsonSerialize()
     {
         $components = [];
diff --git a/vendor/sabre/vobject/lib/Component/VCard.php b/vendor/sabre/vobject/lib/Component/VCard.php
index 2430df621..eac789842 100644
--- a/vendor/sabre/vobject/lib/Component/VCard.php
+++ b/vendor/sabre/vobject/lib/Component/VCard.php
@@ -445,6 +445,7 @@ class VCard extends VObject\Document
      *
      * @return array
      */
+    #[\ReturnTypeWillChange]
     public function jsonSerialize()
     {
         // A vcard does not have sub-components, so we're overriding this
diff --git a/vendor/sabre/vobject/lib/ElementList.php b/vendor/sabre/vobject/lib/ElementList.php
index 56058cbd5..860512649 100644
--- a/vendor/sabre/vobject/lib/ElementList.php
+++ b/vendor/sabre/vobject/lib/ElementList.php
@@ -25,6 +25,7 @@ class ElementList extends ArrayIterator
      * @param int   $offset
      * @param mixed $value
      */
+    #[\ReturnTypeWillChange]
     public function offsetSet($offset, $value)
     {
         throw new LogicException('You can not add new objects to an ElementList');
@@ -37,6 +38,7 @@ class ElementList extends ArrayIterator
      *
      * @param int $offset
      */
+    #[\ReturnTypeWillChange]
     public function offsetUnset($offset)
     {
         throw new LogicException('You can not remove objects from an ElementList');
diff --git a/vendor/sabre/vobject/lib/ITip/Broker.php b/vendor/sabre/vobject/lib/ITip/Broker.php
index 4e0368e13..b66a59f54 100644
--- a/vendor/sabre/vobject/lib/ITip/Broker.php
+++ b/vendor/sabre/vobject/lib/ITip/Broker.php
@@ -547,9 +547,13 @@ class Broker
                 // properties changed in the event, or simply if there's a
                 // difference in instances that the attendee is invited to.
 
+                $oldAttendeeInstances = array_keys($attendee['oldInstances']);
+                $newAttendeeInstances = array_keys($attendee['newInstances']);
+
                 $message->significantChange =
                     'REQUEST' === $attendee['forceSend'] ||
-                    array_keys($attendee['oldInstances']) != array_keys($attendee['newInstances']) ||
+                    count($oldAttendeeInstances) != count($newAttendeeInstances) ||
+                    count(array_diff($oldAttendeeInstances, $newAttendeeInstances)) > 0 ||
                     $oldEventInfo['significantChangeHash'] !== $eventInfo['significantChangeHash'];
 
                 foreach ($attendee['newInstances'] as $instanceId => $instanceInfo) {
@@ -816,7 +820,10 @@ class Broker
         $instances = [];
         $exdate = [];
 
+        $significantChangeEventProperties = [];
+
         foreach ($calendar->VEVENT as $vevent) {
+            $eventSignificantChangeHash = '';
             $rrule = [];
 
             if (is_null($uid)) {
@@ -930,19 +937,26 @@ class Broker
                 if (isset($vevent->$prop)) {
                     $propertyValues = $vevent->select($prop);
 
-                    $significantChangeHash .= $prop.':';
+                    $eventSignificantChangeHash .= $prop.':';
 
                     if ('EXDATE' === $prop) {
-                        $significantChangeHash .= implode(',', $exdate).';';
+                        $eventSignificantChangeHash .= implode(',', $exdate).';';
                     } elseif ('RRULE' === $prop) {
-                        $significantChangeHash .= implode(',', $rrule).';';
+                        $eventSignificantChangeHash .= implode(',', $rrule).';';
                     } else {
                         foreach ($propertyValues as $val) {
-                            $significantChangeHash .= $val->getValue().';';
+                            $eventSignificantChangeHash .= $val->getValue().';';
                         }
                     }
                 }
             }
+            $significantChangeEventProperties[] = $eventSignificantChangeHash;
+        }
+
+        asort($significantChangeEventProperties);
+
+        foreach ($significantChangeEventProperties as $eventSignificantChangeHash) {
+            $significantChangeHash .= $eventSignificantChangeHash;
         }
         $significantChangeHash = md5($significantChangeHash);
 
diff --git a/vendor/sabre/vobject/lib/Node.php b/vendor/sabre/vobject/lib/Node.php
index 4c0c04f72..2041b2ac7 100644
--- a/vendor/sabre/vobject/lib/Node.php
+++ b/vendor/sabre/vobject/lib/Node.php
@@ -73,6 +73,7 @@ abstract class Node implements \IteratorAggregate, \ArrayAccess, \Countable, \Js
      *
      * @return array
      */
+    #[\ReturnTypeWillChange]
     abstract public function jsonSerialize();
 
     /**
@@ -102,6 +103,7 @@ abstract class Node implements \IteratorAggregate, \ArrayAccess, \Countable, \Js
      *
      * @return ElementList
      */
+    #[\ReturnTypeWillChange]
     public function getIterator()
     {
         if (!is_null($this->iterator)) {
@@ -157,6 +159,7 @@ abstract class Node implements \IteratorAggregate, \ArrayAccess, \Countable, \Js
      *
      * @return int
      */
+    #[\ReturnTypeWillChange]
     public function count()
     {
         $it = $this->getIterator();
@@ -177,6 +180,7 @@ abstract class Node implements \IteratorAggregate, \ArrayAccess, \Countable, \Js
      *
      * @return bool
      */
+    #[\ReturnTypeWillChange]
     public function offsetExists($offset)
     {
         $iterator = $this->getIterator();
@@ -193,6 +197,7 @@ abstract class Node implements \IteratorAggregate, \ArrayAccess, \Countable, \Js
      *
      * @return mixed
      */
+    #[\ReturnTypeWillChange]
     public function offsetGet($offset)
     {
         $iterator = $this->getIterator();
@@ -208,6 +213,7 @@ abstract class Node implements \IteratorAggregate, \ArrayAccess, \Countable, \Js
      * @param int   $offset
      * @param mixed $value
      */
+    #[\ReturnTypeWillChange]
     public function offsetSet($offset, $value)
     {
         $iterator = $this->getIterator();
@@ -228,6 +234,7 @@ abstract class Node implements \IteratorAggregate, \ArrayAccess, \Countable, \Js
      *
      * @param int $offset
      */
+    #[\ReturnTypeWillChange]
     public function offsetUnset($offset)
     {
         $iterator = $this->getIterator();
diff --git a/vendor/sabre/vobject/lib/Parameter.php b/vendor/sabre/vobject/lib/Parameter.php
index 72f2ecbcb..7e4d55743 100644
--- a/vendor/sabre/vobject/lib/Parameter.php
+++ b/vendor/sabre/vobject/lib/Parameter.php
@@ -321,6 +321,7 @@ class Parameter extends Node
      *
      * @return array
      */
+    #[\ReturnTypeWillChange]
     public function jsonSerialize()
     {
         return $this->value;
@@ -354,6 +355,7 @@ class Parameter extends Node
      *
      * @return ElementList
      */
+    #[\ReturnTypeWillChange]
     public function getIterator()
     {
         if (!is_null($this->iterator)) {
diff --git a/vendor/sabre/vobject/lib/Parser/MimeDir.php b/vendor/sabre/vobject/lib/Parser/MimeDir.php
index 385d340d7..db0f81531 100644
--- a/vendor/sabre/vobject/lib/Parser/MimeDir.php
+++ b/vendor/sabre/vobject/lib/Parser/MimeDir.php
@@ -439,7 +439,7 @@ class MimeDir extends Parser
             $propObj->add(null, $namelessParameter);
         }
 
-        if ('QUOTED-PRINTABLE' === strtoupper($propObj['ENCODING'])) {
+        if (isset($propObj['ENCODING']) && 'QUOTED-PRINTABLE' === strtoupper($propObj['ENCODING'])) {
             $propObj->setQuotedPrintableValue($this->extractQuotedPrintableValue());
         } else {
             $charset = $this->charset;
@@ -518,7 +518,7 @@ class MimeDir extends Parser
      *
      * Now for the parameters
      *
-     * If delimiter is not set (null) this method will just return a string.
+     * If delimiter is not set (empty string) this method will just return a string.
      * If it's a comma or a semi-colon the string will be split on those
      * characters, and always return an array.
      *
diff --git a/vendor/sabre/vobject/lib/Property.php b/vendor/sabre/vobject/lib/Property.php
index f9cf8e38e..50cda9684 100644
--- a/vendor/sabre/vobject/lib/Property.php
+++ b/vendor/sabre/vobject/lib/Property.php
@@ -52,7 +52,7 @@ abstract class Property extends Node
      * In case this is a multi-value property. This string will be used as a
      * delimiter.
      *
-     * @var string|null
+     * @var string
      */
     public $delimiter = ';';
 
@@ -276,6 +276,7 @@ abstract class Property extends Node
      *
      * @return array
      */
+    #[\ReturnTypeWillChange]
     public function jsonSerialize()
     {
         $parameters = [];
@@ -387,6 +388,7 @@ abstract class Property extends Node
      *
      * @return bool
      */
+    #[\ReturnTypeWillChange]
     public function offsetExists($name)
     {
         if (is_int($name)) {
@@ -413,6 +415,7 @@ abstract class Property extends Node
      *
      * @return Node
      */
+    #[\ReturnTypeWillChange]
     public function offsetGet($name)
     {
         if (is_int($name)) {
@@ -433,6 +436,7 @@ abstract class Property extends Node
      * @param string $name
      * @param mixed  $value
      */
+    #[\ReturnTypeWillChange]
     public function offsetSet($name, $value)
     {
         if (is_int($name)) {
@@ -453,6 +457,7 @@ abstract class Property extends Node
      *
      * @param string $name
      */
+    #[\ReturnTypeWillChange]
     public function offsetUnset($name)
     {
         if (is_int($name)) {
diff --git a/vendor/sabre/vobject/lib/Property/Binary.php b/vendor/sabre/vobject/lib/Property/Binary.php
index ec6713fdd..1262dd054 100644
--- a/vendor/sabre/vobject/lib/Property/Binary.php
+++ b/vendor/sabre/vobject/lib/Property/Binary.php
@@ -24,9 +24,9 @@ class Binary extends Property
      * In case this is a multi-value property. This string will be used as a
      * delimiter.
      *
-     * @var string|null
+     * @var string
      */
-    public $delimiter = null;
+    public $delimiter = '';
 
     /**
      * Updates the current value.
diff --git a/vendor/sabre/vobject/lib/Property/FloatValue.php b/vendor/sabre/vobject/lib/Property/FloatValue.php
index 0d0346968..e780ae6c1 100644
--- a/vendor/sabre/vobject/lib/Property/FloatValue.php
+++ b/vendor/sabre/vobject/lib/Property/FloatValue.php
@@ -21,7 +21,7 @@ class FloatValue extends Property
      * In case this is a multi-value property. This string will be used as a
      * delimiter.
      *
-     * @var string|null
+     * @var string
      */
     public $delimiter = ';';
 
diff --git a/vendor/sabre/vobject/lib/Property/ICalendar/CalAddress.php b/vendor/sabre/vobject/lib/Property/ICalendar/CalAddress.php
index 86be66c15..2dbbc6eaf 100644
--- a/vendor/sabre/vobject/lib/Property/ICalendar/CalAddress.php
+++ b/vendor/sabre/vobject/lib/Property/ICalendar/CalAddress.php
@@ -19,9 +19,9 @@ class CalAddress extends Text
      * In case this is a multi-value property. This string will be used as a
      * delimiter.
      *
-     * @var string|null
+     * @var string
      */
-    public $delimiter = null;
+    public $delimiter = '';
 
     /**
      * Returns the type of value.
diff --git a/vendor/sabre/vobject/lib/Property/ICalendar/DateTime.php b/vendor/sabre/vobject/lib/Property/ICalendar/DateTime.php
index d635e17ae..ca71633b9 100644
--- a/vendor/sabre/vobject/lib/Property/ICalendar/DateTime.php
+++ b/vendor/sabre/vobject/lib/Property/ICalendar/DateTime.php
@@ -300,6 +300,7 @@ class DateTime extends Property
      * @param string $name
      * @param mixed  $value
      */
+    #[\ReturnTypeWillChange]
     public function offsetSet($name, $value)
     {
         parent::offsetSet($name, $value);
diff --git a/vendor/sabre/vobject/lib/Property/ICalendar/Duration.php b/vendor/sabre/vobject/lib/Property/ICalendar/Duration.php
index 87f008160..e18fe191e 100644
--- a/vendor/sabre/vobject/lib/Property/ICalendar/Duration.php
+++ b/vendor/sabre/vobject/lib/Property/ICalendar/Duration.php
@@ -22,7 +22,7 @@ class Duration extends Property
      * In case this is a multi-value property. This string will be used as a
      * delimiter.
      *
-     * @var string|null
+     * @var string
      */
     public $delimiter = ',';
 
diff --git a/vendor/sabre/vobject/lib/Property/ICalendar/Period.php b/vendor/sabre/vobject/lib/Property/ICalendar/Period.php
index eb3752770..ae8a78911 100644
--- a/vendor/sabre/vobject/lib/Property/ICalendar/Period.php
+++ b/vendor/sabre/vobject/lib/Property/ICalendar/Period.php
@@ -23,7 +23,7 @@ class Period extends Property
      * In case this is a multi-value property. This string will be used as a
      * delimiter.
      *
-     * @var string|null
+     * @var string
      */
     public $delimiter = ',';
 
diff --git a/vendor/sabre/vobject/lib/Property/Time.php b/vendor/sabre/vobject/lib/Property/Time.php
index 544b5ced3..1b81609aa 100644
--- a/vendor/sabre/vobject/lib/Property/Time.php
+++ b/vendor/sabre/vobject/lib/Property/Time.php
@@ -19,9 +19,9 @@ class Time extends Text
      * In case this is a multi-value property. This string will be used as a
      * delimiter.
      *
-     * @var string|null
+     * @var string
      */
-    public $delimiter = null;
+    public $delimiter = '';
 
     /**
      * Returns the type of value.
diff --git a/vendor/sabre/vobject/lib/Property/Uri.php b/vendor/sabre/vobject/lib/Property/Uri.php
index 830cd3f18..1ad1fb199 100644
--- a/vendor/sabre/vobject/lib/Property/Uri.php
+++ b/vendor/sabre/vobject/lib/Property/Uri.php
@@ -20,9 +20,9 @@ class Uri extends Text
      * In case this is a multi-value property. This string will be used as a
      * delimiter.
      *
-     * @var string|null
+     * @var string
      */
-    public $delimiter = null;
+    public $delimiter = '';
 
     /**
      * Returns the type of value.
diff --git a/vendor/sabre/vobject/lib/Property/UtcOffset.php b/vendor/sabre/vobject/lib/Property/UtcOffset.php
index 248ed40ea..04b88447f 100644
--- a/vendor/sabre/vobject/lib/Property/UtcOffset.php
+++ b/vendor/sabre/vobject/lib/Property/UtcOffset.php
@@ -17,9 +17,9 @@ class UtcOffset extends Text
      * In case this is a multi-value property. This string will be used as a
      * delimiter.
      *
-     * @var string|null
+     * @var string
      */
-    public $delimiter = null;
+    public $delimiter = '';
 
     /**
      * Returns the type of value.
diff --git a/vendor/sabre/vobject/lib/Property/VCard/DateAndOrTime.php b/vendor/sabre/vobject/lib/Property/VCard/DateAndOrTime.php
index 09918b31a..7bf79c48c 100644
--- a/vendor/sabre/vobject/lib/Property/VCard/DateAndOrTime.php
+++ b/vendor/sabre/vobject/lib/Property/VCard/DateAndOrTime.php
@@ -24,9 +24,9 @@ class DateAndOrTime extends Property
     /**
      * Field separator.
      *
-     * @var string|null
+     * @var string
      */
-    public $delimiter = null;
+    public $delimiter = '';
 
     /**
      * Returns the type of value.
diff --git a/vendor/sabre/vobject/lib/Property/VCard/TimeStamp.php b/vendor/sabre/vobject/lib/Property/VCard/TimeStamp.php
index fccf2d600..da6ea3d44 100644
--- a/vendor/sabre/vobject/lib/Property/VCard/TimeStamp.php
+++ b/vendor/sabre/vobject/lib/Property/VCard/TimeStamp.php
@@ -21,9 +21,9 @@ class TimeStamp extends Text
      * In case this is a multi-value property. This string will be used as a
      * delimiter.
      *
-     * @var string|null
+     * @var string
      */
-    public $delimiter = null;
+    public $delimiter = '';
 
     /**
      * Returns the type of value.
diff --git a/vendor/sabre/vobject/lib/Recur/EventIterator.php b/vendor/sabre/vobject/lib/Recur/EventIterator.php
index e42ca1360..61f05d7de 100644
--- a/vendor/sabre/vobject/lib/Recur/EventIterator.php
+++ b/vendor/sabre/vobject/lib/Recur/EventIterator.php
@@ -198,6 +198,7 @@ class EventIterator implements \Iterator
      *
      * @return DateTimeImmutable
      */
+    #[\ReturnTypeWillChange]
     public function current()
     {
         if ($this->currentDate) {
@@ -229,9 +230,13 @@ class EventIterator implements \Iterator
         if (!$this->valid()) {
             return;
         }
-        $end = clone $this->currentDate;
+        if ($this->currentOverriddenEvent && $this->currentOverriddenEvent->DTEND) {
+            return $this->currentOverriddenEvent->DTEND->getDateTime($this->timeZone);
+        } else {
+            $end = clone $this->currentDate;
 
-        return $end->modify('+'.$this->eventDuration.' seconds');
+            return $end->modify('+'.$this->eventDuration.' seconds');
+        }
     }
 
     /**
@@ -281,6 +286,7 @@ class EventIterator implements \Iterator
      *
      * @return int
      */
+    #[\ReturnTypeWillChange]
     public function key()
     {
         // The counter is always 1 ahead.
@@ -293,6 +299,7 @@ class EventIterator implements \Iterator
      *
      * @return bool
      */
+    #[\ReturnTypeWillChange]
     public function valid()
     {
         if ($this->counter > Settings::$maxRecurrences && -1 !== Settings::$maxRecurrences) {
@@ -304,7 +311,10 @@ class EventIterator implements \Iterator
 
     /**
      * Sets the iterator back to the starting point.
+     *
+     * @return void
      */
+    #[\ReturnTypeWillChange]
     public function rewind()
     {
         $this->recurIterator->rewind();
@@ -327,7 +337,10 @@ class EventIterator implements \Iterator
 
     /**
      * Advances the iterator with one step.
+     *
+     * @return void
      */
+    #[\ReturnTypeWillChange]
     public function next()
     {
         $this->currentOverriddenEvent = null;
diff --git a/vendor/sabre/vobject/lib/Recur/RDateIterator.php b/vendor/sabre/vobject/lib/Recur/RDateIterator.php
index d117e152c..5d56657fa 100644
--- a/vendor/sabre/vobject/lib/Recur/RDateIterator.php
+++ b/vendor/sabre/vobject/lib/Recur/RDateIterator.php
@@ -35,6 +35,7 @@ class RDateIterator implements Iterator
 
     /* Implementation of the Iterator interface {{{ */
 
+    #[\ReturnTypeWillChange]
     public function current()
     {
         if (!$this->valid()) {
@@ -49,6 +50,7 @@ class RDateIterator implements Iterator
      *
      * @return int
      */
+    #[\ReturnTypeWillChange]
     public function key()
     {
         return $this->counter;
@@ -60,6 +62,7 @@ class RDateIterator implements Iterator
      *
      * @return bool
      */
+    #[\ReturnTypeWillChange]
     public function valid()
     {
         return $this->counter <= count($this->dates);
@@ -67,7 +70,10 @@ class RDateIterator implements Iterator
 
     /**
      * Resets the iterator.
+     *
+     * @return void
      */
+    #[\ReturnTypeWillChange]
     public function rewind()
     {
         $this->currentDate = clone $this->startDate;
@@ -76,7 +82,10 @@ class RDateIterator implements Iterator
 
     /**
      * Goes on to the next iteration.
+     *
+     * @return void
      */
+    #[\ReturnTypeWillChange]
     public function next()
     {
         ++$this->counter;
diff --git a/vendor/sabre/vobject/lib/Recur/RRuleIterator.php b/vendor/sabre/vobject/lib/Recur/RRuleIterator.php
index 0511f0ade..d556aa6c3 100644
--- a/vendor/sabre/vobject/lib/Recur/RRuleIterator.php
+++ b/vendor/sabre/vobject/lib/Recur/RRuleIterator.php
@@ -38,6 +38,7 @@ class RRuleIterator implements Iterator
 
     /* Implementation of the Iterator interface {{{ */
 
+    #[\ReturnTypeWillChange]
     public function current()
     {
         if (!$this->valid()) {
@@ -52,6 +53,7 @@ class RRuleIterator implements Iterator
      *
      * @return int
      */
+    #[\ReturnTypeWillChange]
     public function key()
     {
         return $this->counter;
@@ -64,6 +66,7 @@ class RRuleIterator implements Iterator
      *
      * @return bool
      */
+    #[\ReturnTypeWillChange]
     public function valid()
     {
         if (null === $this->currentDate) {
@@ -78,7 +81,10 @@ class RRuleIterator implements Iterator
 
     /**
      * Resets the iterator.
+     *
+     * @return void
      */
+    #[\ReturnTypeWillChange]
     public function rewind()
     {
         $this->currentDate = clone $this->startDate;
@@ -87,7 +93,10 @@ class RRuleIterator implements Iterator
 
     /**
      * Goes on to the next iteration.
+     *
+     * @return void
      */
+    #[\ReturnTypeWillChange]
     public function next()
     {
         // Otherwise, we find the next event in the normal RRULE
diff --git a/vendor/sabre/vobject/lib/TimeZoneUtil.php b/vendor/sabre/vobject/lib/TimeZoneUtil.php
index 2c407fee6..6422c0930 100644
--- a/vendor/sabre/vobject/lib/TimeZoneUtil.php
+++ b/vendor/sabre/vobject/lib/TimeZoneUtil.php
@@ -2,6 +2,16 @@
 
 namespace Sabre\VObject;
 
+use DateTimeZone;
+use InvalidArgumentException;
+use Sabre\VObject\TimezoneGuesser\FindFromOffset;
+use Sabre\VObject\TimezoneGuesser\FindFromTimezoneIdentifier;
+use Sabre\VObject\TimezoneGuesser\FindFromTimezoneMap;
+use Sabre\VObject\TimezoneGuesser\GuessFromLicEntry;
+use Sabre\VObject\TimezoneGuesser\GuessFromMsTzId;
+use Sabre\VObject\TimezoneGuesser\TimezoneFinder;
+use Sabre\VObject\TimezoneGuesser\TimezoneGuesser;
+
 /**
  * Time zone name translation.
  *
@@ -14,17 +24,136 @@ namespace Sabre\VObject;
  */
 class TimeZoneUtil
 {
+    /** @var self */
+    private static $instance = null;
+
+    /** @var TimezoneGuesser[] */
+    private $timezoneGuessers = [];
+
+    /** @var TimezoneFinder[] */
+    private $timezoneFinders = [];
+
+    private function __construct()
+    {
+        $this->addGuesser('lic', new GuessFromLicEntry());
+        $this->addGuesser('msTzId', new GuessFromMsTzId());
+        $this->addFinder('tzid', new FindFromTimezoneIdentifier());
+        $this->addFinder('tzmap', new FindFromTimezoneMap());
+        $this->addFinder('offset', new FindFromOffset());
+    }
+
+    private static function getInstance(): self
+    {
+        if (null === self::$instance) {
+            self::$instance = new self();
+        }
+
+        return self::$instance;
+    }
+
+    private function addGuesser(string $key, TimezoneGuesser $guesser): void
+    {
+        $this->timezoneGuessers[$key] = $guesser;
+    }
+
+    private function addFinder(string $key, TimezoneFinder $finder): void
+    {
+        $this->timezoneFinders[$key] = $finder;
+    }
+
+    /**
+     * This method will try to find out the correct timezone for an iCalendar
+     * date-time value.
+     *
+     * You must pass the contents of the TZID parameter, as well as the full
+     * calendar.
+     *
+     * If the lookup fails, this method will return the default PHP timezone
+     * (as configured using date_default_timezone_set, or the date.timezone ini
+     * setting).
+     *
+     * Alternatively, if $failIfUncertain is set to true, it will throw an
+     * exception if we cannot accurately determine the timezone.
+     */
+    private function findTimeZone(string $tzid, Component $vcalendar = null, bool $failIfUncertain = false): DateTimeZone
+    {
+        foreach ($this->timezoneFinders as $timezoneFinder) {
+            $timezone = $timezoneFinder->find($tzid, $failIfUncertain);
+            if (!$timezone instanceof DateTimeZone) {
+                continue;
+            }
+
+            return $timezone;
+        }
+
+        if ($vcalendar) {
+            // If that didn't work, we will scan VTIMEZONE objects
+            foreach ($vcalendar->select('VTIMEZONE') as $vtimezone) {
+                if ((string) $vtimezone->TZID === $tzid) {
+                    foreach ($this->timezoneGuessers as $timezoneGuesser) {
+                        $timezone = $timezoneGuesser->guess($vtimezone, $failIfUncertain);
+                        if (!$timezone instanceof DateTimeZone) {
+                            continue;
+                        }
+
+                        return $timezone;
+                    }
+                }
+            }
+        }
+
+        if ($failIfUncertain) {
+            throw new InvalidArgumentException('We were unable to determine the correct PHP timezone for tzid: '.$tzid);
+        }
+
+        // If we got all the way here, we default to whatever has been set as the PHP default timezone.
+        return new DateTimeZone(date_default_timezone_get());
+    }
+
+    public static function addTimezoneGuesser(string $key, TimezoneGuesser $guesser): void
+    {
+        self::getInstance()->addGuesser($key, $guesser);
+    }
+
+    public static function addTimezoneFinder(string $key, TimezoneFinder $finder): void
+    {
+        self::getInstance()->addFinder($key, $finder);
+    }
+
+    /**
+     * @param string $tzid
+     * @param false  $failIfUncertain
+     *
+     * @return DateTimeZone
+     */
+    public static function getTimeZone($tzid, Component $vcalendar = null, $failIfUncertain = false)
+    {
+        return self::getInstance()->findTimeZone($tzid, $vcalendar, $failIfUncertain);
+    }
+
+    public static function clean(): void
+    {
+        self::$instance = null;
+    }
+
+    // Keeping things for backwards compatibility
+    /**
+     * @var array|null
+     *
+     * @deprecated
+     */
     public static $map = null;
 
     /**
      * List of microsoft exchange timezone ids.
      *
      * Source: http://msdn.microsoft.com/en-us/library/aa563018(loband).aspx
+     *
+     * @deprecated
      */
     public static $microsoftExchangeMap = [
         0 => 'UTC',
         31 => 'Africa/Casablanca',
-
         // Insanely, id #2 is used for both Europe/Lisbon, and Europe/Sarajevo.
         // I'm not even kidding.. We handle this special case in the
         // getTimeZone method.
@@ -104,134 +233,10 @@ class TimeZoneUtil
     ];
 
     /**
-     * This method will try to find out the correct timezone for an iCalendar
-     * date-time value.
-     *
-     * You must pass the contents of the TZID parameter, as well as the full
-     * calendar.
-     *
-     * If the lookup fails, this method will return the default PHP timezone
-     * (as configured using date_default_timezone_set, or the date.timezone ini
-     * setting).
-     *
-     * Alternatively, if $failIfUncertain is set to true, it will throw an
-     * exception if we cannot accurately determine the timezone.
-     *
-     * @param string                  $tzid
-     * @param Sabre\VObject\Component $vcalendar
-     *
-     * @return \DateTimeZone
-     */
-    public static function getTimeZone($tzid, Component $vcalendar = null, $failIfUncertain = false)
-    {
-        // First we will just see if the tzid is a support timezone identifier.
-        //
-        // The only exception is if the timezone starts with (. This is to
-        // handle cases where certain microsoft products generate timezone
-        // identifiers that for instance look like:
-        //
-        // (GMT+01.00) Sarajevo/Warsaw/Zagreb
-        //
-        // Since PHP 5.5.10, the first bit will be used as the timezone and
-        // this method will return just GMT+01:00. This is wrong, because it
-        // doesn't take DST into account.
-        if ('(' !== $tzid[0]) {
-            // PHP has a bug that logs PHP warnings even it shouldn't:
-            // https://bugs.php.net/bug.php?id=67881
-            //
-            // That's why we're checking if we'll be able to successfully instantiate
-            // \DateTimeZone() before doing so. Otherwise we could simply instantiate
-            // and catch the exception.
-            $tzIdentifiers = \DateTimeZone::listIdentifiers();
-
-            try {
-                if (
-                    (in_array($tzid, $tzIdentifiers)) ||
-                    (preg_match('/^GMT(\+|-)([0-9]{4})$/', $tzid, $matches)) ||
-                    (in_array($tzid, self::getIdentifiersBC()))
-                ) {
-                    return new \DateTimeZone($tzid);
-                }
-            } catch (\Exception $e) {
-            }
-        }
-
-        self::loadTzMaps();
-
-        // Next, we check if the tzid is somewhere in our tzid map.
-        if (isset(self::$map[$tzid])) {
-            return new \DateTimeZone(self::$map[$tzid]);
-        }
-
-        // Some Microsoft products prefix the offset first, so let's strip that off
-        // and see if it is our tzid map.  We don't want to check for this first just
-        // in case there are overrides in our tzid map.
-        if (preg_match('/^\((UTC|GMT)(\+|\-)[\d]{2}\:[\d]{2}\) (.*)/', $tzid, $matches)) {
-            $tzidAlternate = $matches[3];
-            if (isset(self::$map[$tzidAlternate])) {
-                return new \DateTimeZone(self::$map[$tzidAlternate]);
-            }
-        }
-
-        // Maybe the author was hyper-lazy and just included an offset. We
-        // support it, but we aren't happy about it.
-        if (preg_match('/^GMT(\+|-)([0-9]{4})$/', $tzid, $matches)) {
-            // Note that the path in the source will never be taken from PHP 5.5.10
-            // onwards. PHP 5.5.10 supports the "GMT+0100" style of format, so it
-            // already gets returned early in this function. Once we drop support
-            // for versions under PHP 5.5.10, this bit can be taken out of the
-            // source.
-            // @codeCoverageIgnoreStart
-            return new \DateTimeZone('Etc/GMT'.$matches[1].ltrim(substr($matches[2], 0, 2), '0'));
-            // @codeCoverageIgnoreEnd
-        }
-
-        if ($vcalendar) {
-            // If that didn't work, we will scan VTIMEZONE objects
-            foreach ($vcalendar->select('VTIMEZONE') as $vtimezone) {
-                if ((string) $vtimezone->TZID === $tzid) {
-                    // Some clients add 'X-LIC-LOCATION' with the olson name.
-                    if (isset($vtimezone->{'X-LIC-LOCATION'})) {
-                        $lic = (string) $vtimezone->{'X-LIC-LOCATION'};
-
-                        // Libical generators may specify strings like
-                        // "SystemV/EST5EDT". For those we must remove the
-                        // SystemV part.
-                        if ('SystemV/' === substr($lic, 0, 8)) {
-                            $lic = substr($lic, 8);
-                        }
-
-                        return self::getTimeZone($lic, null, $failIfUncertain);
-                    }
-                    // Microsoft may add a magic number, which we also have an
-                    // answer for.
-                    if (isset($vtimezone->{'X-MICROSOFT-CDO-TZID'})) {
-                        $cdoId = (int) $vtimezone->{'X-MICROSOFT-CDO-TZID'}->getValue();
-
-                        // 2 can mean both Europe/Lisbon and Europe/Sarajevo.
-                        if (2 === $cdoId && false !== strpos((string) $vtimezone->TZID, 'Sarajevo')) {
-                            return new \DateTimeZone('Europe/Sarajevo');
-                        }
-
-                        if (isset(self::$microsoftExchangeMap[$cdoId])) {
-                            return new \DateTimeZone(self::$microsoftExchangeMap[$cdoId]);
-                        }
-                    }
-                }
-            }
-        }
-
-        if ($failIfUncertain) {
-            throw new \InvalidArgumentException('We were unable to determine the correct PHP timezone for tzid: '.$tzid);
-        }
-
-        // If we got all the way here, we default to UTC.
-        return new \DateTimeZone(date_default_timezone_get());
-    }
-
-    /**
      * This method will load in all the tz mapping information, if it's not yet
      * done.
+     *
+     * @deprecated
      */
     public static function loadTzMaps()
     {
@@ -257,6 +262,8 @@ class TimeZoneUtil
      * (See timezonedata/php-bc.php and timezonedata php-workaround.php)
      *
      * @return array
+     *
+     * @deprecated
      */
     public static function getIdentifiersBC()
     {
diff --git a/vendor/sabre/vobject/lib/Version.php b/vendor/sabre/vobject/lib/Version.php
index 63452400f..64938bf0b 100644
--- a/vendor/sabre/vobject/lib/Version.php
+++ b/vendor/sabre/vobject/lib/Version.php
@@ -14,5 +14,5 @@ class Version
     /**
      * Full version number.
      */
-    const VERSION = '4.3.5';
+    const VERSION = '4.4.1';
 }