--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/vendor/sabre/vobject/lib/DateTimeParser.php	Sat Jan 13 09:06:10 2018 -0500
@@ -0,0 +1,428 @@
+<?php
+
+namespace Sabre\VObject;
+
+use DateTime;
+use DateTimeZone;
+use DateInterval;
+use InvalidArgumentException;
+use LogicException;
+
+/**
+ * DateTimeParser
+ *
+ * This class is responsible for parsing the several different date and time
+ * formats iCalendar and vCards have.
+ *
+ * @copyright Copyright (C) 2011-2015 fruux GmbH (https://fruux.com/).
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class DateTimeParser {
+
+    /**
+     * Parses an iCalendar (rfc5545) formatted datetime and returns a DateTime object
+     *
+     * Specifying a reference timezone is optional. It will only be used
+     * if the non-UTC format is used. The argument is used as a reference, the
+     * returned DateTime object will still be in the UTC timezone.
+     *
+     * @param string $dt
+     * @param DateTimeZone $tz
+     * @return DateTime
+     */
+    static public function parseDateTime($dt, DateTimeZone $tz = null) {
+
+        // Format is YYYYMMDD + "T" + hhmmss
+        $result = preg_match('/^([0-9]{4})([0-1][0-9])([0-3][0-9])T([0-2][0-9])([0-5][0-9])([0-5][0-9])([Z]?)$/',$dt,$matches);
+
+        if (!$result) {
+            throw new LogicException('The supplied iCalendar datetime value is incorrect: ' . $dt);
+        }
+
+        if ($matches[7]==='Z' || is_null($tz)) {
+            $tz = new DateTimeZone('UTC');
+        }
+        $date = new DateTime($matches[1] . '-' . $matches[2] . '-' . $matches[3] . ' ' . $matches[4] . ':' . $matches[5] .':' . $matches[6], $tz);
+
+        // Still resetting the timezone, to normalize everything to UTC
+        // $date->setTimeZone(new \DateTimeZone('UTC'));
+        return $date;
+
+    }
+
+    /**
+     * Parses an iCalendar (rfc5545) formatted date and returns a DateTime object.
+     *
+     * @param string $date
+     * @param DateTimeZone $tz
+     * @return DateTime
+     */
+    static public function parseDate($date, DateTimeZone $tz = null) {
+
+        // Format is YYYYMMDD
+        $result = preg_match('/^([0-9]{4})([0-1][0-9])([0-3][0-9])$/',$date,$matches);
+
+        if (!$result) {
+            throw new LogicException('The supplied iCalendar date value is incorrect: ' . $date);
+        }
+
+        if (is_null($tz)) {
+            $tz = new DateTimeZone('UTC');
+        }
+
+        $date = new DateTime($matches[1] . '-' . $matches[2] . '-' . $matches[3], $tz);
+        return $date;
+
+    }
+
+    /**
+     * Parses an iCalendar (RFC5545) formatted duration value.
+     *
+     * This method will either return a DateTimeInterval object, or a string
+     * suitable for strtotime or DateTime::modify.
+     *
+     * @param string $duration
+     * @param bool $asString
+     * @return DateInterval|string
+     */
+    static public function parseDuration($duration, $asString = false) {
+
+        $result = preg_match('/^(?P<plusminus>\+|-)?P((?P<week>\d+)W)?((?P<day>\d+)D)?(T((?P<hour>\d+)H)?((?P<minute>\d+)M)?((?P<second>\d+)S)?)?$/', $duration, $matches);
+        if (!$result) {
+            throw new LogicException('The supplied iCalendar duration value is incorrect: ' . $duration);
+        }
+
+        if (!$asString) {
+            $invert = false;
+            if ($matches['plusminus']==='-') {
+                $invert = true;
+            }
+
+
+            $parts = array(
+                'week',
+                'day',
+                'hour',
+                'minute',
+                'second',
+            );
+            foreach($parts as $part) {
+                $matches[$part] = isset($matches[$part])&&$matches[$part]?(int)$matches[$part]:0;
+            }
+
+
+            // We need to re-construct the $duration string, because weeks and
+            // days are not supported by DateInterval in the same string.
+            $duration = 'P';
+            $days = $matches['day'];
+            if ($matches['week']) {
+                $days+=$matches['week']*7;
+            }
+            if ($days)
+                $duration.=$days . 'D';
+
+            if ($matches['minute'] || $matches['second'] || $matches['hour']) {
+                $duration.='T';
+
+                if ($matches['hour'])
+                    $duration.=$matches['hour'].'H';
+
+                if ($matches['minute'])
+                    $duration.=$matches['minute'].'M';
+
+                if ($matches['second'])
+                    $duration.=$matches['second'].'S';
+
+            }
+
+            if ($duration==='P') {
+                $duration = 'PT0S';
+            }
+            $iv = new DateInterval($duration);
+            if ($invert) $iv->invert = true;
+
+            return $iv;
+
+        }
+
+
+
+        $parts = array(
+            'week',
+            'day',
+            'hour',
+            'minute',
+            'second',
+        );
+
+        $newDur = '';
+        foreach($parts as $part) {
+            if (isset($matches[$part]) && $matches[$part]) {
+                $newDur.=' '.$matches[$part] . ' ' . $part . 's';
+            }
+        }
+
+        $newDur = ($matches['plusminus']==='-'?'-':'+') . trim($newDur);
+        if ($newDur === '+') {
+            $newDur = '+0 seconds';
+        };
+        return $newDur;
+
+    }
+
+    /**
+     * Parses either a Date or DateTime, or Duration value.
+     *
+     * @param string $date
+     * @param DateTimeZone|string $referenceTz
+     * @return DateTime|DateInterval
+     */
+    static public function parse($date, $referenceTz = null) {
+
+        if ($date[0]==='P' || ($date[0]==='-' && $date[1]==='P')) {
+            return self::parseDuration($date);
+        } elseif (strlen($date)===8) {
+            return self::parseDate($date, $referenceTz);
+        } else {
+            return self::parseDateTime($date, $referenceTz);
+        }
+
+    }
+
+    /**
+     * This method parses a vCard date and or time value.
+     *
+     * This can be used for the DATE, DATE-TIME, TIMESTAMP and
+     * DATE-AND-OR-TIME value.
+     *
+     * This method returns an array, not a DateTime value.
+     *
+     * The elements in the array are in the following order:
+     * year, month, date, hour, minute, second, timezone
+     *
+     * Almost any part of the string may be omitted. It's for example legal to
+     * just specify seconds, leave out the year, etc.
+     *
+     * Timezone is either returned as 'Z' or as '+08:00'
+     *
+     * For any non-specified values null is returned.
+     *
+     * List of date formats that are supported:
+     * YYYY
+     * YYYY-MM
+     * YYYYMMDD
+     * --MMDD
+     * ---DD
+     *
+     * YYYY-MM-DD
+     * --MM-DD
+     * ---DD
+     *
+     * List of supported time formats:
+     *
+     * HH
+     * HHMM
+     * HHMMSS
+     * -MMSS
+     * --SS
+     *
+     * HH
+     * HH:MM
+     * HH:MM:SS
+     * -MM:SS
+     * --SS
+     *
+     * A full basic-format date-time string looks like :
+     * 20130603T133901
+     *
+     * A full extended-format date-time string looks like :
+     * 2013-06-03T13:39:01
+     *
+     * Times may be postfixed by a timezone offset. This can be either 'Z' for
+     * UTC, or a string like -0500 or +1100.
+     *
+     * @param string $date
+     * @return array
+     */
+    static public function parseVCardDateTime($date) {
+
+        $regex = '/^
+            (?:  # date part
+                (?:
+                    (?: (?P<year> [0-9]{4}) (?: -)?| --)
+                    (?P<month> [0-9]{2})?
+                |---)
+                (?P<date> [0-9]{2})?
+            )?
+            (?:T  # time part
+                (?P<hour> [0-9]{2} | -)
+                (?P<minute> [0-9]{2} | -)?
+                (?P<second> [0-9]{2})?
+
+                (?P<timezone> # timezone offset
+
+                    Z | (?: \+|-)(?: [0-9]{4})
+
+                )?
+
+            )?
+            $/x';
+
+
+        if (!preg_match($regex, $date, $matches)) {
+
+            // Attempting to parse the extended format.
+            $regex = '/^
+                (?: # date part
+                    (?: (?P<year> [0-9]{4}) - | -- )
+                    (?P<month> [0-9]{2}) -
+                    (?P<date> [0-9]{2})
+                )?
+                (?:T # time part
+
+                    (?: (?P<hour> [0-9]{2}) : | -)
+                    (?: (?P<minute> [0-9]{2}) : | -)?
+                    (?P<second> [0-9]{2})?
+
+                    (?P<timezone> # timezone offset
+
+                        Z | (?: \+|-)(?: [0-9]{2}:[0-9]{2})
+
+                    )?
+
+                )?
+                $/x';
+
+            if (!preg_match($regex, $date, $matches)) {
+                throw new InvalidArgumentException('Invalid vCard date-time string: ' . $date);
+            }
+
+        }
+        $parts = array(
+            'year',
+            'month',
+            'date',
+            'hour',
+            'minute',
+            'second',
+            'timezone'
+        );
+
+        $result = array();
+        foreach($parts as $part) {
+
+            if (empty($matches[$part])) {
+                $result[$part] = null;
+            } elseif ($matches[$part] === '-' || $matches[$part] === '--') {
+                $result[$part] = null;
+            } else {
+                $result[$part] = $matches[$part];
+            }
+
+        }
+
+        return $result;
+
+    }
+
+    /**
+     * This method parses a vCard TIME value.
+     *
+     * This method returns an array, not a DateTime value.
+     *
+     * The elements in the array are in the following order:
+     * hour, minute, second, timezone
+     *
+     * Almost any part of the string may be omitted. It's for example legal to
+     * just specify seconds, leave out the hour etc.
+     *
+     * Timezone is either returned as 'Z' or as '+08:00'
+     *
+     * For any non-specified values null is returned.
+     *
+     * List of supported time formats:
+     *
+     * HH
+     * HHMM
+     * HHMMSS
+     * -MMSS
+     * --SS
+     *
+     * HH
+     * HH:MM
+     * HH:MM:SS
+     * -MM:SS
+     * --SS
+     *
+     * A full basic-format time string looks like :
+     * 133901
+     *
+     * A full extended-format time string looks like :
+     * 13:39:01
+     *
+     * Times may be postfixed by a timezone offset. This can be either 'Z' for
+     * UTC, or a string like -0500 or +11:00.
+     *
+     * @param string $date
+     * @return array
+     */
+    static public function parseVCardTime($date) {
+
+        $regex = '/^
+            (?P<hour> [0-9]{2} | -)
+            (?P<minute> [0-9]{2} | -)?
+            (?P<second> [0-9]{2})?
+
+            (?P<timezone> # timezone offset
+
+                Z | (?: \+|-)(?: [0-9]{4})
+
+            )?
+            $/x';
+
+
+        if (!preg_match($regex, $date, $matches)) {
+
+            // Attempting to parse the extended format.
+            $regex = '/^
+                (?: (?P<hour> [0-9]{2}) : | -)
+                (?: (?P<minute> [0-9]{2}) : | -)?
+                (?P<second> [0-9]{2})?
+
+                (?P<timezone> # timezone offset
+
+                    Z | (?: \+|-)(?: [0-9]{2}:[0-9]{2})
+
+                )?
+                $/x';
+
+            if (!preg_match($regex, $date, $matches)) {
+                throw new InvalidArgumentException('Invalid vCard time string: ' . $date);
+            }
+
+        }
+        $parts = array(
+            'hour',
+            'minute',
+            'second',
+            'timezone'
+        );
+
+        $result = array();
+        foreach($parts as $part) {
+
+            if (empty($matches[$part])) {
+                $result[$part] = null;
+            } elseif ($matches[$part] === '-') {
+                $result[$part] = null;
+            } else {
+                $result[$part] = $matches[$part];
+            }
+
+        }
+
+        return $result;
+
+    }
+}