initial sabre upgrade (needs lots of work - to wit: authentication, redo the browser interface, and rework event export/import)

21 files changed, 2932 insertions, 0 deletions

diff --git a/vendor/sabre/vobject/lib/Property/Binary.php b/vendor/sabre/vobject/lib/Property/Binary.php
new file mode 100644
index 000000000..d54cae25d
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/Binary.php
@@ -0,0 +1,128 @@
+<?php
+
+namespace Sabre\VObject\Property;
+
+use Sabre\VObject\Property;
+
+/**
+ * BINARY property.
+ *
+ * This object represents BINARY values.
+ *
+ * Binary values are most commonly used by the iCalendar ATTACH property, and
+ * the vCard PHOTO property.
+ *
+ * This property will transparently encode and decode to base64.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class Binary extends Property {
+
+    /**
+     * In case this is a multi-value property. This string will be used as a
+     * delimiter.
+     *
+     * @var string|null
+     */
+    public $delimiter = null;
+
+    /**
+     * Updates the current value.
+     *
+     * This may be either a single, or multiple strings in an array.
+     *
+     * @param string|array $value
+     *
+     * @return void
+     */
+    function setValue($value) {
+
+        if (is_array($value)) {
+
+            if (count($value) === 1) {
+                $this->value = $value[0];
+            } else {
+                throw new \InvalidArgumentException('The argument must either be a string or an array with only one child');
+            }
+
+        } else {
+
+            $this->value = $value;
+
+        }
+
+    }
+
+    /**
+     * Sets a raw value coming from a mimedir (iCalendar/vCard) file.
+     *
+     * This has been 'unfolded', so only 1 line will be passed. Unescaping is
+     * not yet done, but parameters are not included.
+     *
+     * @param string $val
+     *
+     * @return void
+     */
+    function setRawMimeDirValue($val) {
+
+        $this->value = base64_decode($val);
+
+    }
+
+    /**
+     * Returns a raw mime-dir representation of the value.
+     *
+     * @return string
+     */
+    function getRawMimeDirValue() {
+
+        return base64_encode($this->value);
+
+    }
+
+    /**
+     * Returns the type of value.
+     *
+     * This corresponds to the VALUE= parameter. Every property also has a
+     * 'default' valueType.
+     *
+     * @return string
+     */
+    function getValueType() {
+
+        return 'BINARY';
+
+    }
+
+    /**
+     * Returns the value, in the format it should be encoded for json.
+     *
+     * This method must always return an array.
+     *
+     * @return array
+     */
+    function getJsonValue() {
+
+        return [base64_encode($this->getValue())];
+
+    }
+
+    /**
+     * Sets the json value, as it would appear in a jCard or jCal object.
+     *
+     * The value must always be an array.
+     *
+     * @param array $value
+     *
+     * @return void
+     */
+    function setJsonValue(array $value) {
+
+        $value = array_map('base64_decode', $value);
+        parent::setJsonValue($value);
+
+    }
+
+}
diff --git a/vendor/sabre/vobject/lib/Property/Boolean.php b/vendor/sabre/vobject/lib/Property/Boolean.php
new file mode 100644
index 000000000..6f5887e25
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/Boolean.php
@@ -0,0 +1,84 @@
+<?php
+
+namespace Sabre\VObject\Property;
+
+use
+    Sabre\VObject\Property;
+
+/**
+ * Boolean property.
+ *
+ * This object represents BOOLEAN values. These are always the case-insenstive
+ * string TRUE or FALSE.
+ *
+ * Automatic conversion to PHP's true and false are done.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class Boolean extends Property {
+
+    /**
+     * Sets a raw value coming from a mimedir (iCalendar/vCard) file.
+     *
+     * This has been 'unfolded', so only 1 line will be passed. Unescaping is
+     * not yet done, but parameters are not included.
+     *
+     * @param string $val
+     *
+     * @return void
+     */
+    function setRawMimeDirValue($val) {
+
+        $val = strtoupper($val) === 'TRUE' ? true : false;
+        $this->setValue($val);
+
+    }
+
+    /**
+     * Returns a raw mime-dir representation of the value.
+     *
+     * @return string
+     */
+    function getRawMimeDirValue() {
+
+        return $this->value ? 'TRUE' : 'FALSE';
+
+    }
+
+    /**
+     * Returns the type of value.
+     *
+     * This corresponds to the VALUE= parameter. Every property also has a
+     * 'default' valueType.
+     *
+     * @return string
+     */
+    function getValueType() {
+
+        return 'BOOLEAN';
+
+    }
+
+    /**
+     * Hydrate data from a XML subtree, as it would appear in a xCard or xCal
+     * object.
+     *
+     * @param array $value
+     *
+     * @return void
+     */
+    function setXmlValue(array $value) {
+
+        $value = array_map(
+            function($value) {
+                return 'true' === $value;
+            },
+            $value
+        );
+        parent::setXmlValue($value);
+
+    }
+
+}
diff --git a/vendor/sabre/vobject/lib/Property/FlatText.php b/vendor/sabre/vobject/lib/Property/FlatText.php
new file mode 100644
index 000000000..2c7b43c29
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/FlatText.php
@@ -0,0 +1,50 @@
+<?php
+
+namespace Sabre\VObject\Property;
+
+/**
+ * FlatText property.
+ *
+ * This object represents certain TEXT values.
+ *
+ * Specifically, this property is used for text values where there is only 1
+ * part. Semi-colons and colons will be de-escaped when deserializing, but if
+ * any semi-colons or commas appear without a backslash, we will not assume
+ * that they are delimiters.
+ *
+ * vCard 2.1 specifically has a whole bunch of properties where this may
+ * happen, as it only defines a delimiter for a few properties.
+ *
+ * vCard 4.0 states something similar. An unescaped semi-colon _may_ be a
+ * delimiter, depending on the property.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class FlatText extends Text {
+
+    /**
+     * Field separator.
+     *
+     * @var string
+     */
+    public $delimiter = ',';
+
+    /**
+     * Sets the value as a quoted-printable encoded string.
+     *
+     * Overriding this so we're not splitting on a ; delimiter.
+     *
+     * @param string $val
+     *
+     * @return void
+     */
+    function setQuotedPrintableValue($val) {
+
+        $val = quoted_printable_decode($val);
+        $this->setValue($val);
+
+    }
+
+}
diff --git a/vendor/sabre/vobject/lib/Property/FloatValue.php b/vendor/sabre/vobject/lib/Property/FloatValue.php
new file mode 100644
index 000000000..15b119549
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/FloatValue.php
@@ -0,0 +1,142 @@
+<?php
+
+namespace Sabre\VObject\Property;
+
+use Sabre\VObject\Property;
+use Sabre\Xml;
+
+/**
+ * Float property.
+ *
+ * This object represents FLOAT values. These can be 1 or more floating-point
+ * numbers.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class FloatValue extends Property {
+
+    /**
+     * In case this is a multi-value property. This string will be used as a
+     * delimiter.
+     *
+     * @var string|null
+     */
+    public $delimiter = ';';
+
+    /**
+     * Sets a raw value coming from a mimedir (iCalendar/vCard) file.
+     *
+     * This has been 'unfolded', so only 1 line will be passed. Unescaping is
+     * not yet done, but parameters are not included.
+     *
+     * @param string $val
+     *
+     * @return void
+     */
+    function setRawMimeDirValue($val) {
+
+        $val = explode($this->delimiter, $val);
+        foreach ($val as &$item) {
+            $item = (float)$item;
+        }
+        $this->setParts($val);
+
+    }
+
+    /**
+     * Returns a raw mime-dir representation of the value.
+     *
+     * @return string
+     */
+    function getRawMimeDirValue() {
+
+        return implode(
+            $this->delimiter,
+            $this->getParts()
+        );
+
+    }
+
+    /**
+     * Returns the type of value.
+     *
+     * This corresponds to the VALUE= parameter. Every property also has a
+     * 'default' valueType.
+     *
+     * @return string
+     */
+    function getValueType() {
+
+        return 'FLOAT';
+
+    }
+
+    /**
+     * Returns the value, in the format it should be encoded for JSON.
+     *
+     * This method must always return an array.
+     *
+     * @return array
+     */
+    function getJsonValue() {
+
+        $val = array_map('floatval', $this->getParts());
+
+        // Special-casing the GEO property.
+        //
+        // See:
+        // http://tools.ietf.org/html/draft-ietf-jcardcal-jcal-04#section-3.4.1.2
+        if ($this->name === 'GEO') {
+            return [$val];
+        }
+
+        return $val;
+
+    }
+
+    /**
+     * Hydrate data from a XML subtree, as it would appear in a xCard or xCal
+     * object.
+     *
+     * @param array $value
+     *
+     * @return void
+     */
+    function setXmlValue(array $value) {
+
+        $value = array_map('floatval', $value);
+        parent::setXmlValue($value);
+
+    }
+
+    /**
+     * This method serializes only the value of a property. This is used to
+     * create xCard or xCal documents.
+     *
+     * @param Xml\Writer $writer  XML writer.
+     *
+     * @return void
+     */
+    protected function xmlSerializeValue(Xml\Writer $writer) {
+
+        // Special-casing the GEO property.
+        //
+        // See:
+        // http://tools.ietf.org/html/rfc6321#section-3.4.1.2
+        if ($this->name === 'GEO') {
+
+            $value = array_map('floatval', $this->getParts());
+
+            $writer->writeElement('latitude', $value[0]);
+            $writer->writeElement('longitude', $value[1]);
+
+        }
+        else {
+            parent::xmlSerializeValue($writer);
+        }
+
+    }
+
+}
diff --git a/vendor/sabre/vobject/lib/Property/ICalendar/CalAddress.php b/vendor/sabre/vobject/lib/Property/ICalendar/CalAddress.php
new file mode 100644
index 000000000..a0c4a9b9a
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/ICalendar/CalAddress.php
@@ -0,0 +1,61 @@
+<?php
+
+namespace Sabre\VObject\Property\ICalendar;
+
+use
+    Sabre\VObject\Property\Text;
+
+/**
+ * CalAddress property.
+ *
+ * This object encodes CAL-ADDRESS values, as defined in rfc5545
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class CalAddress extends Text {
+
+    /**
+     * In case this is a multi-value property. This string will be used as a
+     * delimiter.
+     *
+     * @var string|null
+     */
+    public $delimiter = null;
+
+    /**
+     * Returns the type of value.
+     *
+     * This corresponds to the VALUE= parameter. Every property also has a
+     * 'default' valueType.
+     *
+     * @return string
+     */
+    function getValueType() {
+
+        return 'CAL-ADDRESS';
+
+    }
+
+    /**
+     * This returns a normalized form of the value.
+     *
+     * This is primarily used right now to turn mixed-cased schemes in user
+     * uris to lower-case.
+     *
+     * Evolution in particular tends to encode mailto: as MAILTO:.
+     *
+     * @return string
+     */
+    function getNormalizedValue() {
+
+        $input = $this->getValue();
+        if (!strpos($input, ':')) {
+            return $input;
+        }
+        list($schema, $everythingElse) = explode(':', $input, 2);
+        return strtolower($schema) . ':' . $everythingElse;
+
+    }
+}
diff --git a/vendor/sabre/vobject/lib/Property/ICalendar/Date.php b/vendor/sabre/vobject/lib/Property/ICalendar/Date.php
new file mode 100644
index 000000000..378a0d60a
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/ICalendar/Date.php
@@ -0,0 +1,18 @@
+<?php
+
+namespace Sabre\VObject\Property\ICalendar;
+
+/**
+ * DateTime property.
+ *
+ * This object represents DATE values, as defined here:
+ *
+ * http://tools.ietf.org/html/rfc5545#section-3.3.5
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class Date extends DateTime {
+
+}
diff --git a/vendor/sabre/vobject/lib/Property/ICalendar/DateTime.php b/vendor/sabre/vobject/lib/Property/ICalendar/DateTime.php
new file mode 100644
index 000000000..d580d4f68
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/ICalendar/DateTime.php
@@ -0,0 +1,404 @@
+<?php
+
+namespace Sabre\VObject\Property\ICalendar;
+
+use DateTimeInterface;
+use DateTimeZone;
+use Sabre\VObject\DateTimeParser;
+use Sabre\VObject\InvalidDataException;
+use Sabre\VObject\Property;
+use Sabre\VObject\TimeZoneUtil;
+
+/**
+ * DateTime property.
+ *
+ * This object represents DATE-TIME values, as defined here:
+ *
+ * http://tools.ietf.org/html/rfc5545#section-3.3.4
+ *
+ * This particular object has a bit of hackish magic that it may also in some
+ * cases represent a DATE value. This is because it's a common usecase to be
+ * able to change a DATE-TIME into a DATE.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class DateTime extends Property {
+
+    /**
+     * In case this is a multi-value property. This string will be used as a
+     * delimiter.
+     *
+     * @var string|null
+     */
+    public $delimiter = ',';
+
+    /**
+     * Sets a multi-valued property.
+     *
+     * You may also specify DateTime objects here.
+     *
+     * @param array $parts
+     *
+     * @return void
+     */
+    function setParts(array $parts) {
+
+        if (isset($parts[0]) && $parts[0] instanceof DateTimeInterface) {
+            $this->setDateTimes($parts);
+        } else {
+            parent::setParts($parts);
+        }
+
+    }
+
+    /**
+     * Updates the current value.
+     *
+     * This may be either a single, or multiple strings in an array.
+     *
+     * Instead of strings, you may also use DateTime here.
+     *
+     * @param string|array|DateTimeInterface $value
+     *
+     * @return void
+     */
+    function setValue($value) {
+
+        if (is_array($value) && isset($value[0]) && $value[0] instanceof DateTimeInterface) {
+            $this->setDateTimes($value);
+        } elseif ($value instanceof DateTimeInterface) {
+            $this->setDateTimes([$value]);
+        } else {
+            parent::setValue($value);
+        }
+
+    }
+
+    /**
+     * Sets a raw value coming from a mimedir (iCalendar/vCard) file.
+     *
+     * This has been 'unfolded', so only 1 line will be passed. Unescaping is
+     * not yet done, but parameters are not included.
+     *
+     * @param string $val
+     *
+     * @return void
+     */
+    function setRawMimeDirValue($val) {
+
+        $this->setValue(explode($this->delimiter, $val));
+
+    }
+
+    /**
+     * Returns a raw mime-dir representation of the value.
+     *
+     * @return string
+     */
+    function getRawMimeDirValue() {
+
+        return implode($this->delimiter, $this->getParts());
+
+    }
+
+    /**
+     * Returns true if this is a DATE-TIME value, false if it's a DATE.
+     *
+     * @return bool
+     */
+    function hasTime() {
+
+        return strtoupper((string)$this['VALUE']) !== 'DATE';
+
+    }
+
+    /**
+     * Returns true if this is a floating DATE or DATE-TIME.
+     *
+     * Note that DATE is always floating.
+     */
+    function isFloating() {
+
+        return
+            !$this->hasTime() ||
+            (
+                !isset($this['TZID']) &&
+                strpos($this->getValue(), 'Z') === false
+            );
+
+    }
+
+    /**
+     * Returns a date-time value.
+     *
+     * Note that if this property contained more than 1 date-time, only the
+     * first will be returned. To get an array with multiple values, call
+     * getDateTimes.
+     *
+     * If no timezone information is known, because it's either an all-day
+     * property or floating time, we will use the DateTimeZone argument to
+     * figure out the exact date.
+     *
+     * @param DateTimeZone $timeZone
+     *
+     * @return DateTimeImmutable
+     */
+    function getDateTime(DateTimeZone $timeZone = null) {
+
+        $dt = $this->getDateTimes($timeZone);
+        if (!$dt) return;
+
+        return $dt[0];
+
+    }
+
+    /**
+     * Returns multiple date-time values.
+     *
+     * If no timezone information is known, because it's either an all-day
+     * property or floating time, we will use the DateTimeZone argument to
+     * figure out the exact date.
+     *
+     * @param DateTimeZone $timeZone
+     *
+     * @return DateTimeImmutable[]
+     * @return \DateTime[]
+     */
+    function getDateTimes(DateTimeZone $timeZone = null) {
+
+        // Does the property have a TZID?
+        $tzid = $this['TZID'];
+
+        if ($tzid) {
+            $timeZone = TimeZoneUtil::getTimeZone((string)$tzid, $this->root);
+        }
+
+        $dts = [];
+        foreach ($this->getParts() as $part) {
+            $dts[] = DateTimeParser::parse($part, $timeZone);
+        }
+        return $dts;
+
+    }
+
+    /**
+     * Sets the property as a DateTime object.
+     *
+     * @param DateTimeInterface $dt
+     * @param bool isFloating If set to true, timezones will be ignored.
+     *
+     * @return void
+     */
+    function setDateTime(DateTimeInterface $dt, $isFloating = false) {
+
+        $this->setDateTimes([$dt], $isFloating);
+
+    }
+
+    /**
+     * Sets the property as multiple date-time objects.
+     *
+     * The first value will be used as a reference for the timezones, and all
+     * the otehr values will be adjusted for that timezone
+     *
+     * @param DateTimeInterface[] $dt
+     * @param bool isFloating If set to true, timezones will be ignored.
+     *
+     * @return void
+     */
+    function setDateTimes(array $dt, $isFloating = false) {
+
+        $values = [];
+
+        if ($this->hasTime()) {
+
+            $tz = null;
+            $isUtc = false;
+
+            foreach ($dt as $d) {
+
+                if ($isFloating) {
+                    $values[] = $d->format('Ymd\\THis');
+                    continue;
+                }
+                if (is_null($tz)) {
+                    $tz = $d->getTimeZone();
+                    $isUtc = in_array($tz->getName(), ['UTC', 'GMT', 'Z', '+00:00']);
+                    if (!$isUtc) {
+                        $this->offsetSet('TZID', $tz->getName());
+                    }
+                } else {
+                    $d = $d->setTimeZone($tz);
+                }
+
+                if ($isUtc) {
+                    $values[] = $d->format('Ymd\\THis\\Z');
+                } else {
+                    $values[] = $d->format('Ymd\\THis');
+                }
+
+            }
+            if ($isUtc || $isFloating) {
+                $this->offsetUnset('TZID');
+            }
+
+        } else {
+
+            foreach ($dt as $d) {
+
+                $values[] = $d->format('Ymd');
+
+            }
+            $this->offsetUnset('TZID');
+
+        }
+
+        $this->value = $values;
+
+    }
+
+    /**
+     * Returns the type of value.
+     *
+     * This corresponds to the VALUE= parameter. Every property also has a
+     * 'default' valueType.
+     *
+     * @return string
+     */
+    function getValueType() {
+
+        return $this->hasTime() ? 'DATE-TIME' : 'DATE';
+
+    }
+
+    /**
+     * Returns the value, in the format it should be encoded for JSON.
+     *
+     * This method must always return an array.
+     *
+     * @return array
+     */
+    function getJsonValue() {
+
+        $dts = $this->getDateTimes();
+        $hasTime = $this->hasTime();
+        $isFloating = $this->isFloating();
+
+        $tz = $dts[0]->getTimeZone();
+        $isUtc = $isFloating ? false : in_array($tz->getName(), ['UTC', 'GMT', 'Z']);
+
+        return array_map(
+            function(DateTimeInterface $dt) use ($hasTime, $isUtc) {
+
+                if ($hasTime) {
+                    return $dt->format('Y-m-d\\TH:i:s') . ($isUtc ? 'Z' : '');
+                } else {
+                    return $dt->format('Y-m-d');
+                }
+
+            },
+            $dts
+        );
+
+    }
+
+    /**
+     * Sets the json value, as it would appear in a jCard or jCal object.
+     *
+     * The value must always be an array.
+     *
+     * @param array $value
+     *
+     * @return void
+     */
+    function setJsonValue(array $value) {
+
+        // dates and times in jCal have one difference to dates and times in
+        // iCalendar. In jCal date-parts are separated by dashes, and
+        // time-parts are separated by colons. It makes sense to just remove
+        // those.
+        $this->setValue(
+            array_map(
+                function($item) {
+
+                    return strtr($item, [':' => '', '-' => '']);
+
+                },
+                $value
+            )
+        );
+
+    }
+
+    /**
+     * We need to intercept offsetSet, because it may be used to alter the
+     * VALUE from DATE-TIME to DATE or vice-versa.
+     *
+     * @param string $name
+     * @param mixed $value
+     *
+     * @return void
+     */
+    function offsetSet($name, $value) {
+
+        parent::offsetSet($name, $value);
+        if (strtoupper($name) !== 'VALUE') {
+            return;
+        }
+
+        // This will ensure that dates are correctly encoded.
+        $this->setDateTimes($this->getDateTimes());
+
+    }
+
+    /**
+     * Validates the node for correctness.
+     *
+     * The following options are supported:
+     *   Node::REPAIR - May attempt to automatically repair the problem.
+     *
+     * This method returns an array with detected problems.
+     * Every element has the following properties:
+     *
+     *  * level - problem level.
+     *  * message - A human-readable string describing the issue.
+     *  * node - A reference to the problematic node.
+     *
+     * The level means:
+     *   1 - The issue was repaired (only happens if REPAIR was turned on)
+     *   2 - An inconsequential issue
+     *   3 - A severe issue.
+     *
+     * @param int $options
+     *
+     * @return array
+     */
+    function validate($options = 0) {
+
+        $messages = parent::validate($options);
+        $valueType = $this->getValueType();
+        $values = $this->getParts();
+        try {
+            foreach ($values as $value) {
+                switch ($valueType) {
+                    case 'DATE' :
+                        DateTimeParser::parseDate($value);
+                        break;
+                    case 'DATE-TIME' :
+                        DateTimeParser::parseDateTime($value);
+                        break;
+                }
+            }
+        } catch (InvalidDataException $e) {
+            $messages[] = [
+                'level'   => 3,
+                'message' => 'The supplied value (' . $value . ') is not a correct ' . $valueType,
+                'node'    => $this,
+            ];
+        }
+        return $messages;
+
+    }
+}
diff --git a/vendor/sabre/vobject/lib/Property/ICalendar/Duration.php b/vendor/sabre/vobject/lib/Property/ICalendar/Duration.php
new file mode 100644
index 000000000..66d366960
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/ICalendar/Duration.php
@@ -0,0 +1,85 @@
+<?php
+
+namespace Sabre\VObject\Property\ICalendar;
+
+use Sabre\VObject\Property;
+use Sabre\VObject\DateTimeParser;
+
+/**
+ * Duration property.
+ *
+ * This object represents DURATION values, as defined here:
+ *
+ * http://tools.ietf.org/html/rfc5545#section-3.3.6
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class Duration extends Property {
+
+    /**
+     * In case this is a multi-value property. This string will be used as a
+     * delimiter.
+     *
+     * @var string|null
+     */
+    public $delimiter = ',';
+
+    /**
+     * Sets a raw value coming from a mimedir (iCalendar/vCard) file.
+     *
+     * This has been 'unfolded', so only 1 line will be passed. Unescaping is
+     * not yet done, but parameters are not included.
+     *
+     * @param string $val
+     *
+     * @return void
+     */
+    function setRawMimeDirValue($val) {
+
+        $this->setValue(explode($this->delimiter, $val));
+
+    }
+
+    /**
+     * Returns a raw mime-dir representation of the value.
+     *
+     * @return string
+     */
+    function getRawMimeDirValue() {
+
+        return implode($this->delimiter, $this->getParts());
+
+    }
+
+    /**
+     * Returns the type of value.
+     *
+     * This corresponds to the VALUE= parameter. Every property also has a
+     * 'default' valueType.
+     *
+     * @return string
+     */
+    function getValueType() {
+
+        return 'DURATION';
+
+    }
+
+    /**
+     * Returns a DateInterval representation of the Duration property.
+     *
+     * If the property has more than one value, only the first is returned.
+     *
+     * @return \DateInterval
+     */
+    function getDateInterval() {
+
+        $parts = $this->getParts();
+        $value = $parts[0];
+        return DateTimeParser::parseDuration($value);
+
+    }
+
+}
diff --git a/vendor/sabre/vobject/lib/Property/ICalendar/Period.php b/vendor/sabre/vobject/lib/Property/ICalendar/Period.php
new file mode 100644
index 000000000..a4561d929
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/ICalendar/Period.php
@@ -0,0 +1,155 @@
+<?php
+
+namespace Sabre\VObject\Property\ICalendar;
+
+use Sabre\VObject\Property;
+use Sabre\VObject\DateTimeParser;
+use Sabre\Xml;
+
+/**
+ * Period property.
+ *
+ * This object represents PERIOD values, as defined here:
+ *
+ * http://tools.ietf.org/html/rfc5545#section-3.8.2.6
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class Period extends Property {
+
+    /**
+     * In case this is a multi-value property. This string will be used as a
+     * delimiter.
+     *
+     * @var string|null
+     */
+    public $delimiter = ',';
+
+    /**
+     * Sets a raw value coming from a mimedir (iCalendar/vCard) file.
+     *
+     * This has been 'unfolded', so only 1 line will be passed. Unescaping is
+     * not yet done, but parameters are not included.
+     *
+     * @param string $val
+     *
+     * @return void
+     */
+    function setRawMimeDirValue($val) {
+
+        $this->setValue(explode($this->delimiter, $val));
+
+    }
+
+    /**
+     * Returns a raw mime-dir representation of the value.
+     *
+     * @return string
+     */
+    function getRawMimeDirValue() {
+
+        return implode($this->delimiter, $this->getParts());
+
+    }
+
+    /**
+     * Returns the type of value.
+     *
+     * This corresponds to the VALUE= parameter. Every property also has a
+     * 'default' valueType.
+     *
+     * @return string
+     */
+    function getValueType() {
+
+        return 'PERIOD';
+
+    }
+
+    /**
+     * Sets the json value, as it would appear in a jCard or jCal object.
+     *
+     * The value must always be an array.
+     *
+     * @param array $value
+     *
+     * @return void
+     */
+    function setJsonValue(array $value) {
+
+        $value = array_map(
+            function($item) {
+
+                return strtr(implode('/', $item), [':' => '', '-' => '']);
+
+            },
+            $value
+        );
+        parent::setJsonValue($value);
+
+    }
+
+    /**
+     * Returns the value, in the format it should be encoded for json.
+     *
+     * This method must always return an array.
+     *
+     * @return array
+     */
+    function getJsonValue() {
+
+        $return = [];
+        foreach ($this->getParts() as $item) {
+
+            list($start, $end) = explode('/', $item, 2);
+
+            $start = DateTimeParser::parseDateTime($start);
+
+            // This is a duration value.
+            if ($end[0] === 'P') {
+                $return[] = [
+                    $start->format('Y-m-d\\TH:i:s'),
+                    $end
+                ];
+            } else {
+                $end = DateTimeParser::parseDateTime($end);
+                $return[] = [
+                    $start->format('Y-m-d\\TH:i:s'),
+                    $end->format('Y-m-d\\TH:i:s'),
+                ];
+            }
+
+        }
+
+        return $return;
+
+    }
+
+    /**
+     * This method serializes only the value of a property. This is used to
+     * create xCard or xCal documents.
+     *
+     * @param Xml\Writer $writer  XML writer.
+     *
+     * @return void
+     */
+    protected function xmlSerializeValue(Xml\Writer $writer) {
+
+        $writer->startElement(strtolower($this->getValueType()));
+        $value = $this->getJsonValue();
+        $writer->writeElement('start', $value[0][0]);
+
+        if ($value[0][1][0] === 'P') {
+            $writer->writeElement('duration', $value[0][1]);
+        }
+        else {
+            $writer->writeElement('end', $value[0][1]);
+        }
+
+        $writer->endElement();
+
+    }
+
+}
diff --git a/vendor/sabre/vobject/lib/Property/ICalendar/Recur.php b/vendor/sabre/vobject/lib/Property/ICalendar/Recur.php
new file mode 100644
index 000000000..a3c36dc64
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/ICalendar/Recur.php
@@ -0,0 +1,293 @@
+<?php
+
+namespace Sabre\VObject\Property\ICalendar;
+
+use Sabre\VObject\Property;
+use Sabre\Xml;
+
+/**
+ * Recur property.
+ *
+ * This object represents RECUR properties.
+ * These values are just used for RRULE and the now deprecated EXRULE.
+ *
+ * The RRULE property may look something like this:
+ *
+ * RRULE:FREQ=MONTHLY;BYDAY=1,2,3;BYHOUR=5.
+ *
+ * This property exposes this as a key=>value array that is accessible using
+ * getParts, and may be set using setParts.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class Recur extends Property {
+
+    /**
+     * Updates the current value.
+     *
+     * This may be either a single, or multiple strings in an array.
+     *
+     * @param string|array $value
+     *
+     * @return void
+     */
+    function setValue($value) {
+
+        // If we're getting the data from json, we'll be receiving an object
+        if ($value instanceof \StdClass) {
+            $value = (array)$value;
+        }
+
+        if (is_array($value)) {
+            $newVal = [];
+            foreach ($value as $k => $v) {
+
+                if (is_string($v)) {
+                    $v = strtoupper($v);
+
+                    // The value had multiple sub-values
+                    if (strpos($v, ',') !== false) {
+                        $v = explode(',', $v);
+                    }
+                    if (strcmp($k, 'until') === 0) {
+                        $v = strtr($v, [':' => '', '-' => '']);
+                    }
+                } elseif (is_array($v)) {
+                    $v = array_map('strtoupper', $v);
+                }
+
+                $newVal[strtoupper($k)] = $v;
+            }
+            $this->value = $newVal;
+        } elseif (is_string($value)) {
+            $this->value = self::stringToArray($value);
+        } else {
+            throw new \InvalidArgumentException('You must either pass a string, or a key=>value array');
+        }
+
+    }
+
+    /**
+     * Returns the current value.
+     *
+     * This method will always return a singular value. If this was a
+     * multi-value object, some decision will be made first on how to represent
+     * it as a string.
+     *
+     * To get the correct multi-value version, use getParts.
+     *
+     * @return string
+     */
+    function getValue() {
+
+        $out = [];
+        foreach ($this->value as $key => $value) {
+            $out[] = $key . '=' . (is_array($value) ? implode(',', $value) : $value);
+        }
+        return strtoupper(implode(';', $out));
+
+    }
+
+    /**
+     * Sets a multi-valued property.
+     *
+     * @param array $parts
+     * @return void
+     */
+    function setParts(array $parts) {
+
+        $this->setValue($parts);
+
+    }
+
+    /**
+     * Returns a multi-valued property.
+     *
+     * This method always returns an array, if there was only a single value,
+     * it will still be wrapped in an array.
+     *
+     * @return array
+     */
+    function getParts() {
+
+        return $this->value;
+
+    }
+
+    /**
+     * Sets a raw value coming from a mimedir (iCalendar/vCard) file.
+     *
+     * This has been 'unfolded', so only 1 line will be passed. Unescaping is
+     * not yet done, but parameters are not included.
+     *
+     * @param string $val
+     *
+     * @return void
+     */
+    function setRawMimeDirValue($val) {
+
+        $this->setValue($val);
+
+    }
+
+    /**
+     * Returns a raw mime-dir representation of the value.
+     *
+     * @return string
+     */
+    function getRawMimeDirValue() {
+
+        return $this->getValue();
+
+    }
+
+    /**
+     * Returns the type of value.
+     *
+     * This corresponds to the VALUE= parameter. Every property also has a
+     * 'default' valueType.
+     *
+     * @return string
+     */
+    function getValueType() {
+
+        return 'RECUR';
+
+    }
+
+    /**
+     * Returns the value, in the format it should be encoded for json.
+     *
+     * This method must always return an array.
+     *
+     * @return array
+     */
+    function getJsonValue() {
+
+        $values = [];
+        foreach ($this->getParts() as $k => $v) {
+            if (strcmp($k, 'UNTIL') === 0) {
+                $date = new DateTime($this->root, null, $v);
+                $values[strtolower($k)] = $date->getJsonValue()[0];
+            } elseif (strcmp($k, 'COUNT') === 0) {
+                $values[strtolower($k)] = intval($v);
+            } else {
+                $values[strtolower($k)] = $v;
+            }
+        }
+        return [$values];
+
+    }
+
+    /**
+     * This method serializes only the value of a property. This is used to
+     * create xCard or xCal documents.
+     *
+     * @param Xml\Writer $writer  XML writer.
+     *
+     * @return void
+     */
+    protected function xmlSerializeValue(Xml\Writer $writer) {
+
+        $valueType = strtolower($this->getValueType());
+
+        foreach ($this->getJsonValue() as $value) {
+            $writer->writeElement($valueType, $value);
+        }
+
+    }
+
+    /**
+     * Parses an RRULE value string, and turns it into a struct-ish array.
+     *
+     * @param string $value
+     *
+     * @return array
+     */
+    static function stringToArray($value) {
+
+        $value = strtoupper($value);
+        $newValue = [];
+        foreach (explode(';', $value) as $part) {
+
+            // Skipping empty parts.
+            if (empty($part)) {
+                continue;
+            }
+            list($partName, $partValue) = explode('=', $part);
+
+            // The value itself had multiple values..
+            if (strpos($partValue, ',') !== false) {
+                $partValue = explode(',', $partValue);
+            }
+            $newValue[$partName] = $partValue;
+
+        }
+
+        return $newValue;
+    }
+
+    /**
+     * Validates the node for correctness.
+     *
+     * The following options are supported:
+     *   Node::REPAIR - May attempt to automatically repair the problem.
+     *
+     * This method returns an array with detected problems.
+     * Every element has the following properties:
+     *
+     *  * level - problem level.
+     *  * message - A human-readable string describing the issue.
+     *  * node - A reference to the problematic node.
+     *
+     * The level means:
+     *   1 - The issue was repaired (only happens if REPAIR was turned on)
+     *   2 - An inconsequential issue
+     *   3 - A severe issue.
+     *
+     * @param int $options
+     *
+     * @return array
+     */
+    function validate($options = 0) {
+
+        $repair = ($options & self::REPAIR);
+
+        $warnings = parent::validate($options);
+        $values = $this->getParts();
+
+        foreach ($values as $key => $value) {
+
+            if (empty($value)) {
+                $warnings[] = [
+                    'level'   => $repair ? 3 : 1,
+                    'message' => 'Invalid value for ' . $key . ' in ' . $this->name,
+                    'node'    => $this
+                ];
+                if ($repair) {
+                    unset($values[$key]);
+                }
+            }
+
+        }
+        if (!isset($values['FREQ'])) {
+            $warnings[] = [
+                'level'   => $repair ? 3 : 1,
+                'message' => 'FREQ is required in ' . $this->name,
+                'node'    => $this
+            ];
+            if ($repair) {
+                $this->parent->remove($this);
+            }
+        }
+        if ($repair) {
+            $this->setValue($values);
+        }
+
+        return $warnings;
+
+    }
+
+}
diff --git a/vendor/sabre/vobject/lib/Property/IntegerValue.php b/vendor/sabre/vobject/lib/Property/IntegerValue.php
new file mode 100644
index 000000000..5bd1887fa
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/IntegerValue.php
@@ -0,0 +1,88 @@
+<?php
+
+namespace Sabre\VObject\Property;
+
+use
+    Sabre\VObject\Property;
+
+/**
+ * Integer property.
+ *
+ * This object represents INTEGER values. These are always a single integer.
+ * They may be preceeded by either + or -.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class IntegerValue extends Property {
+
+    /**
+     * Sets a raw value coming from a mimedir (iCalendar/vCard) file.
+     *
+     * This has been 'unfolded', so only 1 line will be passed. Unescaping is
+     * not yet done, but parameters are not included.
+     *
+     * @param string $val
+     *
+     * @return void
+     */
+    function setRawMimeDirValue($val) {
+
+        $this->setValue((int)$val);
+
+    }
+
+    /**
+     * Returns a raw mime-dir representation of the value.
+     *
+     * @return string
+     */
+    function getRawMimeDirValue() {
+
+        return $this->value;
+
+    }
+
+    /**
+     * Returns the type of value.
+     *
+     * This corresponds to the VALUE= parameter. Every property also has a
+     * 'default' valueType.
+     *
+     * @return string
+     */
+    function getValueType() {
+
+        return 'INTEGER';
+
+    }
+
+    /**
+     * Returns the value, in the format it should be encoded for json.
+     *
+     * This method must always return an array.
+     *
+     * @return array
+     */
+    function getJsonValue() {
+
+        return [(int)$this->getValue()];
+
+    }
+
+    /**
+     * Hydrate data from a XML subtree, as it would appear in a xCard or xCal
+     * object.
+     *
+     * @param array $value
+     *
+     * @return void
+     */
+    function setXmlValue(array $value) {
+
+        $value = array_map('intval', $value);
+        parent::setXmlValue($value);
+
+    }
+}
diff --git a/vendor/sabre/vobject/lib/Property/Text.php b/vendor/sabre/vobject/lib/Property/Text.php
new file mode 100644
index 000000000..2e16ac534
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/Text.php
@@ -0,0 +1,413 @@
+<?php
+
+namespace Sabre\VObject\Property;
+
+use Sabre\VObject\Property;
+use Sabre\VObject\Component;
+use Sabre\VObject\Parser\MimeDir;
+use Sabre\VObject\Document;
+use Sabre\Xml;
+
+/**
+ * Text property.
+ *
+ * This object represents TEXT values.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class Text extends Property {
+
+    /**
+     * In case this is a multi-value property. This string will be used as a
+     * delimiter.
+     *
+     * @var string
+     */
+    public $delimiter = ',';
+
+    /**
+     * List of properties that are considered 'structured'.
+     *
+     * @var array
+     */
+    protected $structuredValues = [
+        // vCard
+        'N',
+        'ADR',
+        'ORG',
+        'GENDER',
+        'CLIENTPIDMAP',
+
+        // iCalendar
+        'REQUEST-STATUS',
+    ];
+
+    /**
+     * Some text components have a minimum number of components.
+     *
+     * N must for instance be represented as 5 components, separated by ;, even
+     * if the last few components are unused.
+     *
+     * @var array
+     */
+    protected $minimumPropertyValues = [
+        'N'   => 5,
+        'ADR' => 7,
+    ];
+
+    /**
+     * Creates the property.
+     *
+     * You can specify the parameters either in key=>value syntax, in which case
+     * parameters will automatically be created, or you can just pass a list of
+     * Parameter objects.
+     *
+     * @param Component $root The root document
+     * @param string $name
+     * @param string|array|null $value
+     * @param array $parameters List of parameters
+     * @param string $group The vcard property group
+     *
+     * @return void
+     */
+    function __construct(Component $root, $name, $value = null, array $parameters = [], $group = null) {
+
+        // There's two types of multi-valued text properties:
+        // 1. multivalue properties.
+        // 2. structured value properties
+        //
+        // The former is always separated by a comma, the latter by semi-colon.
+        if (in_array($name, $this->structuredValues)) {
+            $this->delimiter = ';';
+        }
+
+        parent::__construct($root, $name, $value, $parameters, $group);
+
+    }
+
+    /**
+     * Sets a raw value coming from a mimedir (iCalendar/vCard) file.
+     *
+     * This has been 'unfolded', so only 1 line will be passed. Unescaping is
+     * not yet done, but parameters are not included.
+     *
+     * @param string $val
+     *
+     * @return void
+     */
+    function setRawMimeDirValue($val) {
+
+        $this->setValue(MimeDir::unescapeValue($val, $this->delimiter));
+
+    }
+
+    /**
+     * Sets the value as a quoted-printable encoded string.
+     *
+     * @param string $val
+     *
+     * @return void
+     */
+    function setQuotedPrintableValue($val) {
+
+        $val = quoted_printable_decode($val);
+
+        // Quoted printable only appears in vCard 2.1, and the only character
+        // that may be escaped there is ;. So we are simply splitting on just
+        // that.
+        //
+        // We also don't have to unescape \\, so all we need to look for is a ;
+        // that's not preceeded with a \.
+        $regex = '# (?<!\\\\) ; #x';
+        $matches = preg_split($regex, $val);
+        $this->setValue($matches);
+
+    }
+
+    /**
+     * Returns a raw mime-dir representation of the value.
+     *
+     * @return string
+     */
+    function getRawMimeDirValue() {
+
+        $val = $this->getParts();
+
+        if (isset($this->minimumPropertyValues[$this->name])) {
+            $val = array_pad($val, $this->minimumPropertyValues[$this->name], '');
+        }
+
+        foreach ($val as &$item) {
+
+            if (!is_array($item)) {
+                $item = [$item];
+            }
+
+            foreach ($item as &$subItem) {
+                $subItem = strtr(
+                    $subItem,
+                    [
+                        '\\' => '\\\\',
+                        ';'  => '\;',
+                        ','  => '\,',
+                        "\n" => '\n',
+                        "\r" => "",
+                    ]
+                );
+            }
+            $item = implode(',', $item);
+
+        }
+
+        return implode($this->delimiter, $val);
+
+    }
+
+    /**
+     * Returns the value, in the format it should be encoded for json.
+     *
+     * This method must always return an array.
+     *
+     * @return array
+     */
+    function getJsonValue() {
+
+        // Structured text values should always be returned as a single
+        // array-item. Multi-value text should be returned as multiple items in
+        // the top-array.
+        if (in_array($this->name, $this->structuredValues)) {
+            return [$this->getParts()];
+        }
+        return $this->getParts();
+
+    }
+
+    /**
+     * Returns the type of value.
+     *
+     * This corresponds to the VALUE= parameter. Every property also has a
+     * 'default' valueType.
+     *
+     * @return string
+     */
+    function getValueType() {
+
+        return 'TEXT';
+
+    }
+
+    /**
+     * Turns the object back into a serialized blob.
+     *
+     * @return string
+     */
+    function serialize() {
+
+        // We need to kick in a special type of encoding, if it's a 2.1 vcard.
+        if ($this->root->getDocumentType() !== Document::VCARD21) {
+            return parent::serialize();
+        }
+
+        $val = $this->getParts();
+
+        if (isset($this->minimumPropertyValues[$this->name])) {
+            $val = array_pad($val, $this->minimumPropertyValues[$this->name], '');
+        }
+
+        // Imploding multiple parts into a single value, and splitting the
+        // values with ;.
+        if (count($val) > 1) {
+            foreach ($val as $k => $v) {
+                $val[$k] = str_replace(';', '\;', $v);
+            }
+            $val = implode(';', $val);
+        } else {
+            $val = $val[0];
+        }
+
+        $str = $this->name;
+        if ($this->group) $str = $this->group . '.' . $this->name;
+        foreach ($this->parameters as $param) {
+
+            if ($param->getValue() === 'QUOTED-PRINTABLE') {
+                continue;
+            }
+            $str .= ';' . $param->serialize();
+
+        }
+
+
+
+        // If the resulting value contains a \n, we must encode it as
+        // quoted-printable.
+        if (strpos($val, "\n") !== false) {
+
+            $str .= ';ENCODING=QUOTED-PRINTABLE:';
+            $lastLine = $str;
+            $out = null;
+
+            // The PHP built-in quoted-printable-encode does not correctly
+            // encode newlines for us. Specifically, the \r\n sequence must in
+            // vcards be encoded as =0D=OA and we must insert soft-newlines
+            // every 75 bytes.
+            for ($ii = 0;$ii < strlen($val);$ii++) {
+                $ord = ord($val[$ii]);
+                // These characters are encoded as themselves.
+                if ($ord >= 32 && $ord <= 126) {
+                    $lastLine .= $val[$ii];
+                } else {
+                    $lastLine .= '=' . strtoupper(bin2hex($val[$ii]));
+                }
+                if (strlen($lastLine) >= 75) {
+                    // Soft line break
+                    $out .= $lastLine . "=\r\n ";
+                    $lastLine = null;
+                }
+
+            }
+            if (!is_null($lastLine)) $out .= $lastLine . "\r\n";
+            return $out;
+
+        } else {
+            $str .= ':' . $val;
+            $out = '';
+            while (strlen($str) > 0) {
+                if (strlen($str) > 75) {
+                    $out .= mb_strcut($str, 0, 75, 'utf-8') . "\r\n";
+                    $str = ' ' . mb_strcut($str, 75, strlen($str), 'utf-8');
+                } else {
+                    $out .= $str . "\r\n";
+                    $str = '';
+                    break;
+                }
+            }
+
+            return $out;
+
+        }
+
+    }
+
+    /**
+     * This method serializes only the value of a property. This is used to
+     * create xCard or xCal documents.
+     *
+     * @param Xml\Writer $writer  XML writer.
+     *
+     * @return void
+     */
+    protected function xmlSerializeValue(Xml\Writer $writer) {
+
+        $values = $this->getParts();
+
+        $map = function($items) use ($values, $writer) {
+            foreach ($items as $i => $item) {
+                $writer->writeElement(
+                    $item,
+                    !empty($values[$i]) ? $values[$i] : null
+                );
+            }
+        };
+
+        switch ($this->name) {
+
+            // Special-casing the REQUEST-STATUS property.
+            //
+            // See:
+            // http://tools.ietf.org/html/rfc6321#section-3.4.1.3
+            case 'REQUEST-STATUS':
+                $writer->writeElement('code', $values[0]);
+                $writer->writeElement('description', $values[1]);
+
+                if (isset($values[2])) {
+                    $writer->writeElement('data', $values[2]);
+                }
+                break;
+
+            case 'N':
+                $map([
+                    'surname',
+                    'given',
+                    'additional',
+                    'prefix',
+                    'suffix'
+                ]);
+                break;
+
+            case 'GENDER':
+                $map([
+                    'sex',
+                    'text'
+                ]);
+                break;
+
+            case 'ADR':
+                $map([
+                    'pobox',
+                    'ext',
+                    'street',
+                    'locality',
+                    'region',
+                    'code',
+                    'country'
+                ]);
+                break;
+
+            case 'CLIENTPIDMAP':
+                $map([
+                    'sourceid',
+                    'uri'
+                ]);
+                break;
+
+            default:
+                parent::xmlSerializeValue($writer);
+        }
+
+    }
+
+    /**
+     * Validates the node for correctness.
+     *
+     * The following options are supported:
+     *   - Node::REPAIR - If something is broken, and automatic repair may
+     *                    be attempted.
+     *
+     * An array is returned with warnings.
+     *
+     * Every item in the array has the following properties:
+     *    * level - (number between 1 and 3 with severity information)
+     *    * message - (human readable message)
+     *    * node - (reference to the offending node)
+     *
+     * @param int $options
+     *
+     * @return array
+     */
+    function validate($options = 0) {
+
+        $warnings = parent::validate($options);
+
+        if (isset($this->minimumPropertyValues[$this->name])) {
+
+            $minimum = $this->minimumPropertyValues[$this->name];
+            $parts = $this->getParts();
+            if (count($parts) < $minimum) {
+                $warnings[] = [
+                    'level'   => $options & self::REPAIR ? 1 : 3,
+                    'message' => 'The ' . $this->name  . ' property must have at least ' . $minimum . ' values. It only has ' . count($parts),
+                    'node'    => $this,
+                ];
+                if ($options & self::REPAIR) {
+                    $parts = array_pad($parts, $minimum, '');
+                    $this->setParts($parts);
+                }
+            }
+
+        }
+        return $warnings;
+
+    }
+}
diff --git a/vendor/sabre/vobject/lib/Property/Time.php b/vendor/sabre/vobject/lib/Property/Time.php
new file mode 100644
index 000000000..dbafc3b85
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/Time.php
@@ -0,0 +1,144 @@
+<?php
+
+namespace Sabre\VObject\Property;
+
+use Sabre\VObject\DateTimeParser;
+
+/**
+ * Time property.
+ *
+ * This object encodes TIME values.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class Time extends Text {
+
+    /**
+     * In case this is a multi-value property. This string will be used as a
+     * delimiter.
+     *
+     * @var string|null
+     */
+    public $delimiter = null;
+
+    /**
+     * Returns the type of value.
+     *
+     * This corresponds to the VALUE= parameter. Every property also has a
+     * 'default' valueType.
+     *
+     * @return string
+     */
+    function getValueType() {
+
+        return 'TIME';
+
+    }
+
+    /**
+     * Sets the JSON value, as it would appear in a jCard or jCal object.
+     *
+     * The value must always be an array.
+     *
+     * @param array $value
+     *
+     * @return void
+     */
+    function setJsonValue(array $value) {
+
+        // Removing colons from value.
+        $value = str_replace(
+            ':',
+            '',
+            $value
+        );
+
+        if (count($value) === 1) {
+            $this->setValue(reset($value));
+        } else {
+            $this->setValue($value);
+        }
+
+    }
+
+    /**
+     * Returns the value, in the format it should be encoded for json.
+     *
+     * This method must always return an array.
+     *
+     * @return array
+     */
+    function getJsonValue() {
+
+        $parts = DateTimeParser::parseVCardTime($this->getValue());
+        $timeStr = '';
+
+        // Hour
+        if (!is_null($parts['hour'])) {
+            $timeStr .= $parts['hour'];
+
+            if (!is_null($parts['minute'])) {
+                $timeStr .= ':';
+            }
+        } else {
+            // We know either minute or second _must_ be set, so we insert a
+            // dash for an empty value.
+            $timeStr .= '-';
+        }
+
+        // Minute
+        if (!is_null($parts['minute'])) {
+            $timeStr .= $parts['minute'];
+
+            if (!is_null($parts['second'])) {
+                $timeStr .= ':';
+            }
+        } else {
+            if (isset($parts['second'])) {
+                // Dash for empty minute
+                $timeStr .= '-';
+            }
+        }
+
+        // Second
+        if (!is_null($parts['second'])) {
+            $timeStr .= $parts['second'];
+        }
+
+        // Timezone
+        if (!is_null($parts['timezone'])) {
+            if ($parts['timezone'] === 'Z') {
+                $timeStr .= 'Z';
+            } else {
+                $timeStr .=
+                    preg_replace('/([0-9]{2})([0-9]{2})$/', '$1:$2', $parts['timezone']);
+            }
+        }
+
+        return [$timeStr];
+
+    }
+
+    /**
+     * Hydrate data from a XML subtree, as it would appear in a xCard or xCal
+     * object.
+     *
+     * @param array $value
+     *
+     * @return void
+     */
+    function setXmlValue(array $value) {
+
+        $value = array_map(
+            function($value) {
+                return str_replace(':', '', $value);
+            },
+            $value
+        );
+        parent::setXmlValue($value);
+
+    }
+
+}
diff --git a/vendor/sabre/vobject/lib/Property/Unknown.php b/vendor/sabre/vobject/lib/Property/Unknown.php
new file mode 100644
index 000000000..7a3373868
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/Unknown.php
@@ -0,0 +1,44 @@
+<?php
+
+namespace Sabre\VObject\Property;
+
+/**
+ * Unknown property.
+ *
+ * This object represents any properties not recognized by the parser.
+ * This type of value has been introduced by the jCal, jCard specs.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class Unknown extends Text {
+
+    /**
+     * Returns the value, in the format it should be encoded for json.
+     *
+     * This method must always return an array.
+     *
+     * @return array
+     */
+    function getJsonValue() {
+
+        return [$this->getRawMimeDirValue()];
+
+    }
+
+    /**
+     * Returns the type of value.
+     *
+     * This corresponds to the VALUE= parameter. Every property also has a
+     * 'default' valueType.
+     *
+     * @return string
+     */
+    function getValueType() {
+
+        return 'UNKNOWN';
+
+    }
+
+}
diff --git a/vendor/sabre/vobject/lib/Property/Uri.php b/vendor/sabre/vobject/lib/Property/Uri.php
new file mode 100644
index 000000000..58e676e60
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/Uri.php
@@ -0,0 +1,122 @@
+<?php
+
+namespace Sabre\VObject\Property;
+
+use Sabre\VObject\Property;
+use Sabre\VObject\Parameter;
+
+/**
+ * URI property.
+ *
+ * This object encodes URI values. vCard 2.1 calls these URL.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class Uri extends Text {
+
+    /**
+     * In case this is a multi-value property. This string will be used as a
+     * delimiter.
+     *
+     * @var string|null
+     */
+    public $delimiter = null;
+
+    /**
+     * Returns the type of value.
+     *
+     * This corresponds to the VALUE= parameter. Every property also has a
+     * 'default' valueType.
+     *
+     * @return string
+     */
+    function getValueType() {
+
+        return 'URI';
+
+    }
+
+    /**
+     * Returns an iterable list of children.
+     *
+     * @return array
+     */
+    function parameters() {
+
+        $parameters = parent::parameters();
+        if (!isset($parameters['VALUE']) && in_array($this->name, ['URL', 'PHOTO'])) {
+            // If we are encoding a URI value, and this URI value has no
+            // VALUE=URI parameter, we add it anyway.
+            //
+            // This is not required by any spec, but both Apple iCal and Apple
+            // AddressBook (at least in version 10.8) will trip over this if
+            // this is not set, and so it improves compatibility.
+            //
+            // See Issue #227 and #235
+            $parameters['VALUE'] = new Parameter($this->root, 'VALUE', 'URI');
+        }
+        return $parameters;
+
+    }
+
+    /**
+     * Sets a raw value coming from a mimedir (iCalendar/vCard) file.
+     *
+     * This has been 'unfolded', so only 1 line will be passed. Unescaping is
+     * not yet done, but parameters are not included.
+     *
+     * @param string $val
+     *
+     * @return void
+     */
+    function setRawMimeDirValue($val) {
+
+        // Normally we don't need to do any type of unescaping for these
+        // properties, however.. we've noticed that Google Contacts
+        // specifically escapes the colon (:) with a blackslash. While I have
+        // no clue why they thought that was a good idea, I'm unescaping it
+        // anyway.
+        //
+        // Good thing backslashes are not allowed in urls. Makes it easy to
+        // assume that a backslash is always intended as an escape character.
+        if ($this->name === 'URL') {
+            $regex = '#  (?: (\\\\ (?: \\\\ | : ) ) ) #x';
+            $matches = preg_split($regex, $val, -1, PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY);
+            $newVal = '';
+            foreach ($matches as $match) {
+                switch ($match) {
+                    case '\:' :
+                        $newVal .= ':';
+                        break;
+                    default :
+                        $newVal .= $match;
+                        break;
+                }
+            }
+            $this->value = $newVal;
+        } else {
+            $this->value = strtr($val, ['\,' => ',']);
+        }
+
+    }
+
+    /**
+     * Returns a raw mime-dir representation of the value.
+     *
+     * @return string
+     */
+    function getRawMimeDirValue() {
+
+        if (is_array($this->value)) {
+            $value = $this->value[0];
+        } else {
+            $value = $this->value;
+        }
+
+        return strtr($value, [',' => '\,']);
+
+    }
+
+}
diff --git a/vendor/sabre/vobject/lib/Property/UtcOffset.php b/vendor/sabre/vobject/lib/Property/UtcOffset.php
new file mode 100644
index 000000000..61895c48e
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/UtcOffset.php
@@ -0,0 +1,77 @@
+<?php
+
+namespace Sabre\VObject\Property;
+
+/**
+ * UtcOffset property.
+ *
+ * This object encodes UTC-OFFSET values.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class UtcOffset extends Text {
+
+    /**
+     * In case this is a multi-value property. This string will be used as a
+     * delimiter.
+     *
+     * @var string|null
+     */
+    public $delimiter = null;
+
+    /**
+     * Returns the type of value.
+     *
+     * This corresponds to the VALUE= parameter. Every property also has a
+     * 'default' valueType.
+     *
+     * @return string
+     */
+    function getValueType() {
+
+        return 'UTC-OFFSET';
+
+    }
+
+    /**
+     * Sets the JSON value, as it would appear in a jCard or jCal object.
+     *
+     * The value must always be an array.
+     *
+     * @param array $value
+     *
+     * @return void
+     */
+    function setJsonValue(array $value) {
+
+        $value = array_map(
+            function($value) {
+                return str_replace(':', '', $value);
+            },
+            $value
+        );
+        parent::setJsonValue($value);
+
+    }
+
+    /**
+     * Returns the value, in the format it should be encoded for JSON.
+     *
+     * This method must always return an array.
+     *
+     * @return array
+     */
+    function getJsonValue() {
+
+        return array_map(
+            function($value) {
+                return substr($value, 0, -2) . ':' .
+                       substr($value, -2);
+            },
+            parent::getJsonValue()
+        );
+
+    }
+}
diff --git a/vendor/sabre/vobject/lib/Property/VCard/Date.php b/vendor/sabre/vobject/lib/Property/VCard/Date.php
new file mode 100644
index 000000000..1ef6dff34
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/VCard/Date.php
@@ -0,0 +1,43 @@
+<?php
+
+namespace Sabre\VObject\Property\VCard;
+
+/**
+ * Date property.
+ *
+ * This object encodes vCard DATE values.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class Date extends DateAndOrTime {
+
+    /**
+     * Returns the type of value.
+     *
+     * This corresponds to the VALUE= parameter. Every property also has a
+     * 'default' valueType.
+     *
+     * @return string
+     */
+    function getValueType() {
+
+        return 'DATE';
+
+    }
+
+    /**
+     * Sets the property as a DateTime object.
+     *
+     * @param \DateTimeInterface $dt
+     *
+     * @return void
+     */
+    function setDateTime(\DateTimeInterface $dt) {
+
+        $this->value = $dt->format('Ymd');
+
+    }
+
+}
diff --git a/vendor/sabre/vobject/lib/Property/VCard/DateAndOrTime.php b/vendor/sabre/vobject/lib/Property/VCard/DateAndOrTime.php
new file mode 100644
index 000000000..650e19cbf
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/VCard/DateAndOrTime.php
@@ -0,0 +1,405 @@
+<?php
+
+namespace Sabre\VObject\Property\VCard;
+
+use DateTimeInterface;
+use DateTimeImmutable;
+use DateTime;
+use Sabre\VObject\DateTimeParser;
+use Sabre\VObject\InvalidDataException;
+use Sabre\VObject\Property;
+use Sabre\Xml;
+
+/**
+ * DateAndOrTime property.
+ *
+ * This object encodes DATE-AND-OR-TIME values.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class DateAndOrTime extends Property {
+
+    /**
+     * Field separator.
+     *
+     * @var null|string
+     */
+    public $delimiter = null;
+
+    /**
+     * Returns the type of value.
+     *
+     * This corresponds to the VALUE= parameter. Every property also has a
+     * 'default' valueType.
+     *
+     * @return string
+     */
+    function getValueType() {
+
+        return 'DATE-AND-OR-TIME';
+
+    }
+
+    /**
+     * Sets a multi-valued property.
+     *
+     * You may also specify DateTime objects here.
+     *
+     * @param array $parts
+     *
+     * @return void
+     */
+    function setParts(array $parts) {
+
+        if (count($parts) > 1) {
+            throw new \InvalidArgumentException('Only one value allowed');
+        }
+        if (isset($parts[0]) && $parts[0] instanceof \DateTime) {
+            $this->setDateTime($parts[0]);
+        } else {
+            parent::setParts($parts);
+        }
+
+    }
+
+    /**
+     * Updates the current value.
+     *
+     * This may be either a single, or multiple strings in an array.
+     *
+     * Instead of strings, you may also use DateTime here.
+     *
+     * @param string|array|\DateTime $value
+     *
+     * @return void
+     */
+    function setValue($value) {
+
+        if ($value instanceof \DateTime) {
+            $this->setDateTime($value);
+        } else {
+            parent::setValue($value);
+        }
+
+    }
+
+    /**
+     * Sets the property as a DateTime object.
+     *
+     * @param DateTimeInterface $dt
+     *
+     * @return void
+     */
+    function setDateTime(DateTimeInterface $dt) {
+
+        $tz = $dt->getTimeZone();
+        $isUtc = in_array($tz->getName(), ['UTC', 'GMT', 'Z']);
+
+        if ($isUtc) {
+            $value = $dt->format('Ymd\\THis\\Z');
+        } else {
+            // Calculating the offset.
+            $value = $dt->format('Ymd\\THisO');
+        }
+
+        $this->value = $value;
+
+    }
+
+    /**
+     * Returns a date-time value.
+     *
+     * Note that if this property contained more than 1 date-time, only the
+     * first will be returned. To get an array with multiple values, call
+     * getDateTimes.
+     *
+     * If no time was specified, we will always use midnight (in the default
+     * timezone) as the time.
+     *
+     * If parts of the date were omitted, such as the year, we will grab the
+     * current values for those. So at the time of writing, if the year was
+     * omitted, we would have filled in 2014.
+     *
+     * @return DateTimeImmutable
+     */
+    function getDateTime() {
+
+        $now = new DateTime();
+
+        $tzFormat = $now->getTimezone()->getOffset($now) === 0 ? '\\Z' : 'O';
+        $nowParts = DateTimeParser::parseVCardDateTime($now->format('Ymd\\This' . $tzFormat));
+
+        $dateParts = DateTimeParser::parseVCardDateTime($this->getValue());
+
+        // This sets all the missing parts to the current date/time.
+        // So if the year was missing for a birthday, we're making it 'this
+        // year'.
+        foreach ($dateParts as $k => $v) {
+            if (is_null($v)) {
+                $dateParts[$k] = $nowParts[$k];
+            }
+        }
+        return new DateTimeImmutable("$dateParts[year]-$dateParts[month]-$dateParts[date] $dateParts[hour]:$dateParts[minute]:$dateParts[second] $dateParts[timezone]");
+
+    }
+
+    /**
+     * Returns the value, in the format it should be encoded for json.
+     *
+     * This method must always return an array.
+     *
+     * @return array
+     */
+    function getJsonValue() {
+
+        $parts = DateTimeParser::parseVCardDateTime($this->getValue());
+
+        $dateStr = '';
+
+        // Year
+        if (!is_null($parts['year'])) {
+
+            $dateStr .= $parts['year'];
+
+            if (!is_null($parts['month'])) {
+                // If a year and a month is set, we need to insert a separator
+                // dash.
+                $dateStr .= '-';
+            }
+
+        } else {
+
+            if (!is_null($parts['month']) || !is_null($parts['date'])) {
+                // Inserting two dashes
+                $dateStr .= '--';
+            }
+
+        }
+
+        // Month
+        if (!is_null($parts['month'])) {
+
+            $dateStr .= $parts['month'];
+
+            if (isset($parts['date'])) {
+                // If month and date are set, we need the separator dash.
+                $dateStr .= '-';
+            }
+
+        } elseif (isset($parts['date'])) {
+            // If the month is empty, and a date is set, we need a 'empty
+            // dash'
+            $dateStr .= '-';
+        }
+
+        // Date
+        if (!is_null($parts['date'])) {
+            $dateStr .= $parts['date'];
+        }
+
+
+        // Early exit if we don't have a time string.
+        if (is_null($parts['hour']) && is_null($parts['minute']) && is_null($parts['second'])) {
+            return [$dateStr];
+        }
+
+        $dateStr .= 'T';
+
+        // Hour
+        if (!is_null($parts['hour'])) {
+
+            $dateStr .= $parts['hour'];
+
+            if (!is_null($parts['minute'])) {
+                $dateStr .= ':';
+            }
+
+        } else {
+            // We know either minute or second _must_ be set, so we insert a
+            // dash for an empty value.
+            $dateStr .= '-';
+        }
+
+        // Minute
+        if (!is_null($parts['minute'])) {
+
+            $dateStr .= $parts['minute'];
+
+            if (!is_null($parts['second'])) {
+                $dateStr .= ':';
+            }
+
+        } elseif (isset($parts['second'])) {
+            // Dash for empty minute
+            $dateStr .= '-';
+        }
+
+        // Second
+        if (!is_null($parts['second'])) {
+            $dateStr .= $parts['second'];
+        }
+
+        // Timezone
+        if (!is_null($parts['timezone'])) {
+            $dateStr .= $parts['timezone'];
+        }
+
+        return [$dateStr];
+
+    }
+
+    /**
+     * This method serializes only the value of a property. This is used to
+     * create xCard or xCal documents.
+     *
+     * @param Xml\Writer $writer  XML writer.
+     *
+     * @return void
+     */
+    protected function xmlSerializeValue(Xml\Writer $writer) {
+
+        $valueType = strtolower($this->getValueType());
+        $parts     = DateTimeParser::parseVCardDateAndOrTime($this->getValue());
+        $value     = '';
+
+        // $d = defined
+        $d = function($part) use ($parts) {
+            return !is_null($parts[$part]);
+        };
+
+        // $r = read
+        $r = function($part) use ($parts) {
+            return $parts[$part];
+        };
+
+        // From the Relax NG Schema.
+        //
+        // # 4.3.1
+        // value-date = element date {
+        //     xsd:string { pattern = "\d{8}|\d{4}-\d\d|--\d\d(\d\d)?|---\d\d" }
+        //   }
+        if (($d('year') ||  $d('month')  ||  $d('date'))
+            && (!$d('hour') && !$d('minute') && !$d('second') && !$d('timezone'))) {
+
+            if ($d('year') && $d('month') && $d('date')) {
+                $value .= $r('year') . $r('month') . $r('date');
+            } elseif ($d('year') && $d('month') && !$d('date')) {
+                $value .= $r('year') . '-' . $r('month');
+            } elseif (!$d('year') && $d('month')) {
+                $value .= '--' . $r('month') . $r('date');
+            } elseif (!$d('year') && !$d('month') && $d('date')) {
+                $value .= '---' . $r('date');
+            }
+
+        // # 4.3.2
+        // value-time = element time {
+        //     xsd:string { pattern = "(\d\d(\d\d(\d\d)?)?|-\d\d(\d\d?)|--\d\d)"
+        //                          ~ "(Z|[+\-]\d\d(\d\d)?)?" }
+        //   }
+        } elseif ((!$d('year') && !$d('month')  && !$d('date'))
+                  && ($d('hour') ||  $d('minute') ||  $d('second'))) {
+
+            if ($d('hour')) {
+                $value .= $r('hour') . $r('minute') . $r('second');
+            } elseif ($d('minute')) {
+                $value .= '-' . $r('minute') . $r('second');
+            } elseif ($d('second')) {
+                $value .= '--' . $r('second');
+            }
+
+            $value .= $r('timezone');
+
+        // # 4.3.3
+        // value-date-time = element date-time {
+        //     xsd:string { pattern = "(\d{8}|--\d{4}|---\d\d)T\d\d(\d\d(\d\d)?)?"
+        //                          ~ "(Z|[+\-]\d\d(\d\d)?)?" }
+        //   }
+        } elseif ($d('date') && $d('hour')) {
+
+            if ($d('year') && $d('month') && $d('date')) {
+                $value .= $r('year') . $r('month') . $r('date');
+            } elseif (!$d('year') && $d('month') && $d('date')) {
+                $value .= '--' . $r('month') . $r('date');
+            } elseif (!$d('year') && !$d('month') && $d('date')) {
+                $value .= '---' . $r('date');
+            }
+
+            $value .= 'T' . $r('hour') . $r('minute') . $r('second') .
+                      $r('timezone');
+
+        }
+
+        $writer->writeElement($valueType, $value);
+
+    }
+
+    /**
+     * Sets a raw value coming from a mimedir (iCalendar/vCard) file.
+     *
+     * This has been 'unfolded', so only 1 line will be passed. Unescaping is
+     * not yet done, but parameters are not included.
+     *
+     * @param string $val
+     *
+     * @return void
+     */
+    function setRawMimeDirValue($val) {
+
+        $this->setValue($val);
+
+    }
+
+    /**
+     * Returns a raw mime-dir representation of the value.
+     *
+     * @return string
+     */
+    function getRawMimeDirValue() {
+
+        return implode($this->delimiter, $this->getParts());
+
+    }
+
+    /**
+     * Validates the node for correctness.
+     *
+     * The following options are supported:
+     *   Node::REPAIR - May attempt to automatically repair the problem.
+     *
+     * This method returns an array with detected problems.
+     * Every element has the following properties:
+     *
+     *  * level - problem level.
+     *  * message - A human-readable string describing the issue.
+     *  * node - A reference to the problematic node.
+     *
+     * The level means:
+     *   1 - The issue was repaired (only happens if REPAIR was turned on)
+     *   2 - An inconsequential issue
+     *   3 - A severe issue.
+     *
+     * @param int $options
+     *
+     * @return array
+     */
+    function validate($options = 0) {
+
+        $messages = parent::validate($options);
+        $value = $this->getValue();
+
+        try {
+            DateTimeParser::parseVCardDateTime($value);
+        } catch (InvalidDataException $e) {
+            $messages[] = [
+                'level'   => 3,
+                'message' => 'The supplied value (' . $value . ') is not a correct DATE-AND-OR-TIME property',
+                'node'    => $this,
+            ];
+        }
+
+        return $messages;
+
+    }
+}
diff --git a/vendor/sabre/vobject/lib/Property/VCard/DateTime.php b/vendor/sabre/vobject/lib/Property/VCard/DateTime.php
new file mode 100644
index 000000000..e7c804ca7
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/VCard/DateTime.php
@@ -0,0 +1,30 @@
+<?php
+
+namespace Sabre\VObject\Property\VCard;
+
+/**
+ * DateTime property.
+ *
+ * This object encodes DATE-TIME values for vCards.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class DateTime extends DateAndOrTime {
+
+    /**
+     * Returns the type of value.
+     *
+     * This corresponds to the VALUE= parameter. Every property also has a
+     * 'default' valueType.
+     *
+     * @return string
+     */
+    function getValueType() {
+
+        return 'DATE-TIME';
+
+    }
+
+}
diff --git a/vendor/sabre/vobject/lib/Property/VCard/LanguageTag.php b/vendor/sabre/vobject/lib/Property/VCard/LanguageTag.php
new file mode 100644
index 000000000..aa7e9178d
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/VCard/LanguageTag.php
@@ -0,0 +1,60 @@
+<?php
+
+namespace Sabre\VObject\Property\VCard;
+
+use
+    Sabre\VObject\Property;
+
+/**
+ * LanguageTag property.
+ *
+ * This object represents LANGUAGE-TAG values as used in vCards.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class LanguageTag extends Property {
+
+    /**
+     * Sets a raw value coming from a mimedir (iCalendar/vCard) file.
+     *
+     * This has been 'unfolded', so only 1 line will be passed. Unescaping is
+     * not yet done, but parameters are not included.
+     *
+     * @param string $val
+     *
+     * @return void
+     */
+    function setRawMimeDirValue($val) {
+
+        $this->setValue($val);
+
+    }
+
+    /**
+     * Returns a raw mime-dir representation of the value.
+     *
+     * @return string
+     */
+    function getRawMimeDirValue() {
+
+        return $this->getValue();
+
+    }
+
+    /**
+     * Returns the type of value.
+     *
+     * This corresponds to the VALUE= parameter. Every property also has a
+     * 'default' valueType.
+     *
+     * @return string
+     */
+    function getValueType() {
+
+        return 'LANGUAGE-TAG';
+
+    }
+
+}
diff --git a/vendor/sabre/vobject/lib/Property/VCard/TimeStamp.php b/vendor/sabre/vobject/lib/Property/VCard/TimeStamp.php
new file mode 100644
index 000000000..9d311f99d
--- /dev/null
+++ b/vendor/sabre/vobject/lib/Property/VCard/TimeStamp.php
@@ -0,0 +1,86 @@
+<?php
+
+namespace Sabre\VObject\Property\VCard;
+
+use Sabre\VObject\DateTimeParser;
+use Sabre\VObject\Property\Text;
+use Sabre\Xml;
+
+/**
+ * TimeStamp property.
+ *
+ * This object encodes TIMESTAMP values.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class TimeStamp extends Text {
+
+    /**
+     * In case this is a multi-value property. This string will be used as a
+     * delimiter.
+     *
+     * @var string|null
+     */
+    public $delimiter = null;
+
+    /**
+     * Returns the type of value.
+     *
+     * This corresponds to the VALUE= parameter. Every property also has a
+     * 'default' valueType.
+     *
+     * @return string
+     */
+    function getValueType() {
+
+        return 'TIMESTAMP';
+
+    }
+
+    /**
+     * Returns the value, in the format it should be encoded for json.
+     *
+     * This method must always return an array.
+     *
+     * @return array
+     */
+    function getJsonValue() {
+
+        $parts = DateTimeParser::parseVCardDateTime($this->getValue());
+
+        $dateStr =
+            $parts['year'] . '-' .
+            $parts['month'] . '-' .
+            $parts['date'] . 'T' .
+            $parts['hour'] . ':' .
+            $parts['minute'] . ':' .
+            $parts['second'];
+
+        // Timezone
+        if (!is_null($parts['timezone'])) {
+            $dateStr .= $parts['timezone'];
+        }
+
+        return [$dateStr];
+
+    }
+
+    /**
+     * This method serializes only the value of a property. This is used to
+     * create xCard or xCal documents.
+     *
+     * @param Xml\Writer $writer  XML writer.
+     *
+     * @return void
+     */
+    protected function xmlSerializeValue(Xml\Writer $writer) {
+
+        // xCard is the only XML and JSON format that has the same date and time
+        // format than vCard.
+        $valueType = strtolower($this->getValueType());
+        $writer->writeElement($valueType, $this->getValue());
+
+    }
+}