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+<?php
+
+namespace Sabre\VObject;
+
+/**
+ * This class is used to determine new for a recurring event, when the next
+ * events occur.
+ *
+ * This iterator may loop infinitely in the future, therefore it is important
+ * that if you use this class, you set hard limits for the amount of iterations
+ * you want to handle.
+ *
+ * Note that currently there is not full support for the entire iCalendar
+ * specification, as it's very complex and contains a lot of permutations
+ * that's not yet used very often in software.
+ *
+ * For the focus has been on features as they actually appear in Calendaring
+ * software, but this may well get expanded as needed / on demand
+ *
+ * The following RRULE properties are supported
+ * * UNTIL
+ * * INTERVAL
+ * * COUNT
+ * * FREQ=DAILY
+ * * BYDAY
+ * * BYHOUR
+ * * FREQ=WEEKLY
+ * * BYDAY
+ * * BYHOUR
+ * * WKST
+ * * FREQ=MONTHLY
+ * * BYMONTHDAY
+ * * BYDAY
+ * * BYSETPOS
+ * * FREQ=YEARLY
+ * * BYMONTH
+ * * BYMONTHDAY (only if BYMONTH is also set)
+ * * BYDAY (only if BYMONTH is also set)
+ *
+ * Anything beyond this is 'undefined', which means that it may get ignored, or
+ * you may get unexpected results. The effect is that in some applications the
+ * specified recurrence may look incorrect, or is missing.
+ *
+ * @copyright Copyright (C) 2007-2013 fruux GmbH (https://fruux.com/).
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://code.google.com/p/sabredav/wiki/License Modified BSD License
+ */
+class RecurrenceIterator implements \Iterator {
+
+ /**
+ * The initial event date
+ *
+ * @var DateTime
+ */
+ public $startDate;
+
+ /**
+ * The end-date of the initial event
+ *
+ * @var DateTime
+ */
+ public $endDate;
+
+ /**
+ * The 'current' recurrence.
+ *
+ * This will be increased for every iteration.
+ *
+ * @var DateTime
+ */
+ public $currentDate;
+
+
+ /**
+ * List of dates that are excluded from the rules.
+ *
+ * This list contains the items that have been overriden by the EXDATE
+ * property.
+ *
+ * @var array
+ */
+ public $exceptionDates = array();
+
+ /**
+ * Base event
+ *
+ * @var Component\VEvent
+ */
+ public $baseEvent;
+
+ /**
+ * List of dates that are overridden by other events.
+ * Similar to $overriddenEvents, but this just contains the original dates.
+ *
+ * @var array
+ */
+ public $overriddenDates = array();
+
+ /**
+ * list of events that are 'overridden'.
+ *
+ * This is an array of Component\VEvent objects.
+ *
+ * @var array
+ */
+ public $overriddenEvents = array();
+
+ /**
+ * Frequency is one of: secondly, minutely, hourly, daily, weekly, monthly,
+ * yearly.
+ *
+ * @var string
+ */
+ public $frequency;
+
+ /**
+ * The last instance of this recurrence, inclusively
+ *
+ * @var DateTime|null
+ */
+ public $until;
+
+ /**
+ * The number of recurrences, or 'null' if infinitely recurring.
+ *
+ * @var int
+ */
+ public $count;
+
+ /**
+ * The interval.
+ *
+ * If for example frequency is set to daily, interval = 2 would mean every
+ * 2 days.
+ *
+ * @var int
+ */
+ public $interval = 1;
+
+ /**
+ * Which seconds to recur.
+ *
+ * This is an array of integers (between 0 and 60)
+ *
+ * @var array
+ */
+ public $bySecond;
+
+ /**
+ * Which minutes to recur
+ *
+ * This is an array of integers (between 0 and 59)
+ *
+ * @var array
+ */
+ public $byMinute;
+
+ /**
+ * Which hours to recur
+ *
+ * This is an array of integers (between 0 and 23)
+ *
+ * @var array
+ */
+ public $byHour;
+
+ /**
+ * Which weekdays to recur.
+ *
+ * This is an array of weekdays
+ *
+ * This may also be preceeded by a positive or negative integer. If present,
+ * this indicates the nth occurrence of a specific day within the monthly or
+ * yearly rrule. For instance, -2TU indicates the second-last tuesday of
+ * the month, or year.
+ *
+ * @var array
+ */
+ public $byDay;
+
+ /**
+ * Which days of the month to recur
+ *
+ * This is an array of days of the months (1-31). The value can also be
+ * negative. -5 for instance means the 5th last day of the month.
+ *
+ * @var array
+ */
+ public $byMonthDay;
+
+ /**
+ * Which days of the year to recur.
+ *
+ * This is an array with days of the year (1 to 366). The values can also
+ * be negative. For instance, -1 will always represent the last day of the
+ * year. (December 31st).
+ *
+ * @var array
+ */
+ public $byYearDay;
+
+ /**
+ * Which week numbers to recur.
+ *
+ * This is an array of integers from 1 to 53. The values can also be
+ * negative. -1 will always refer to the last week of the year.
+ *
+ * @var array
+ */
+ public $byWeekNo;
+
+ /**
+ * Which months to recur
+ *
+ * This is an array of integers from 1 to 12.
+ *
+ * @var array
+ */
+ public $byMonth;
+
+ /**
+ * Which items in an existing st to recur.
+ *
+ * These numbers work together with an existing by* rule. It specifies
+ * exactly which items of the existing by-rule to filter.
+ *
+ * Valid values are 1 to 366 and -1 to -366. As an example, this can be
+ * used to recur the last workday of the month.
+ *
+ * This would be done by setting frequency to 'monthly', byDay to
+ * 'MO,TU,WE,TH,FR' and bySetPos to -1.
+ *
+ * @var array
+ */
+ public $bySetPos;
+
+ /**
+ * When a week starts
+ *
+ * @var string
+ */
+ public $weekStart = 'MO';
+
+ /**
+ * The current item in the list
+ *
+ * @var int
+ */
+ public $counter = 0;
+
+ /**
+ * Simple mapping from iCalendar day names to day numbers
+ *
+ * @var array
+ */
+ private $dayMap = array(
+ 'SU' => 0,
+ 'MO' => 1,
+ 'TU' => 2,
+ 'WE' => 3,
+ 'TH' => 4,
+ 'FR' => 5,
+ 'SA' => 6,
+ );
+
+ /**
+ * Mappings between the day number and english day name.
+ *
+ * @var array
+ */
+ private $dayNames = array(
+ 0 => 'Sunday',
+ 1 => 'Monday',
+ 2 => 'Tuesday',
+ 3 => 'Wednesday',
+ 4 => 'Thursday',
+ 5 => 'Friday',
+ 6 => 'Saturday',
+ );
+
+ /**
+ * If the current iteration of the event is an overriden event, this
+ * property will hold the VObject
+ *
+ * @var Component
+ */
+ private $currentOverriddenEvent;
+
+ /**
+ * This property may contain the date of the next not-overridden event.
+ * This date is calculated sometimes a bit early, before overridden events
+ * are evaluated.
+ *
+ * @var DateTime
+ */
+ private $nextDate;
+
+ /**
+ * This counts the number of overridden events we've handled so far
+ *
+ * @var int
+ */
+ private $handledOverridden = 0;
+
+ /**
+ * Creates the iterator
+ *
+ * You should pass a VCALENDAR component, as well as the UID of the event
+ * we're going to traverse.
+ *
+ * @param Component $vcal
+ * @param string|null $uid
+ */
+ public function __construct(Component $vcal, $uid=null) {
+
+ if (is_null($uid)) {
+ if ($vcal->name === 'VCALENDAR') {
+ throw new \InvalidArgumentException('If you pass a VCALENDAR object, you must pass a uid argument as well');
+ }
+ $components = array($vcal);
+ $uid = (string)$vcal->uid;
+ } else {
+ $components = $vcal->select('VEVENT');
+ }
+ foreach($components as $component) {
+ if ((string)$component->uid == $uid) {
+ if (isset($component->{'RECURRENCE-ID'})) {
+ $this->overriddenEvents[$component->DTSTART->getDateTime()->getTimeStamp()] = $component;
+ $this->overriddenDates[] = $component->{'RECURRENCE-ID'}->getDateTime();
+ } else {
+ $this->baseEvent = $component;
+ }
+ }
+ }
+
+ ksort($this->overriddenEvents);
+
+ if (!$this->baseEvent) {
+ throw new \InvalidArgumentException('Could not find a base event with uid: ' . $uid);
+ }
+
+ $this->startDate = clone $this->baseEvent->DTSTART->getDateTime();
+
+ $this->endDate = null;
+ if (isset($this->baseEvent->DTEND)) {
+ $this->endDate = clone $this->baseEvent->DTEND->getDateTime();
+ } else {
+ $this->endDate = clone $this->startDate;
+ if (isset($this->baseEvent->DURATION)) {
+ $this->endDate->add(DateTimeParser::parse($this->baseEvent->DURATION->value));
+ } elseif ($this->baseEvent->DTSTART->getDateType()===Property\DateTime::DATE) {
+ $this->endDate->modify('+1 day');
+ }
+ }
+ $this->currentDate = clone $this->startDate;
+
+ $rrule = (string)$this->baseEvent->RRULE;
+
+ $parts = explode(';', $rrule);
+
+ // If no rrule was specified, we create a default setting
+ if (!$rrule) {
+ $this->frequency = 'daily';
+ $this->count = 1;
+ } else foreach($parts as $part) {
+
+ list($key, $value) = explode('=', $part, 2);
+
+ switch(strtoupper($key)) {
+
+ case 'FREQ' :
+ if (!in_array(
+ strtolower($value),
+ array('secondly','minutely','hourly','daily','weekly','monthly','yearly')
+ )) {
+ throw new \InvalidArgumentException('Unknown value for FREQ=' . strtoupper($value));
+
+ }
+ $this->frequency = strtolower($value);
+ break;
+
+ case 'UNTIL' :
+ $this->until = DateTimeParser::parse($value);
+
+ // In some cases events are generated with an UNTIL=
+ // parameter before the actual start of the event.
+ //
+ // Not sure why this is happening. We assume that the
+ // intention was that the event only recurs once.
+ //
+ // So we are modifying the parameter so our code doesn't
+ // break.
+ if($this->until < $this->baseEvent->DTSTART->getDateTime()) {
+ $this->until = $this->baseEvent->DTSTART->getDateTime();
+ }
+ break;
+
+ case 'COUNT' :
+ $this->count = (int)$value;
+ break;
+
+ case 'INTERVAL' :
+ $this->interval = (int)$value;
+ if ($this->interval < 1) {
+ throw new \InvalidArgumentException('INTERVAL in RRULE must be a positive integer!');
+ }
+ break;
+
+ case 'BYSECOND' :
+ $this->bySecond = explode(',', $value);
+ break;
+
+ case 'BYMINUTE' :
+ $this->byMinute = explode(',', $value);
+ break;
+
+ case 'BYHOUR' :
+ $this->byHour = explode(',', $value);
+ break;
+
+ case 'BYDAY' :
+ $this->byDay = explode(',', strtoupper($value));
+ break;
+
+ case 'BYMONTHDAY' :
+ $this->byMonthDay = explode(',', $value);
+ break;
+
+ case 'BYYEARDAY' :
+ $this->byYearDay = explode(',', $value);
+ break;
+
+ case 'BYWEEKNO' :
+ $this->byWeekNo = explode(',', $value);
+ break;
+
+ case 'BYMONTH' :
+ $this->byMonth = explode(',', $value);
+ break;
+
+ case 'BYSETPOS' :
+ $this->bySetPos = explode(',', $value);
+ break;
+
+ case 'WKST' :
+ $this->weekStart = strtoupper($value);
+ break;
+
+ }
+
+ }
+
+ // Parsing exception dates
+ if (isset($this->baseEvent->EXDATE)) {
+ foreach($this->baseEvent->EXDATE as $exDate) {
+
+ foreach(explode(',', (string)$exDate) as $exceptionDate) {
+
+ $this->exceptionDates[] =
+ DateTimeParser::parse($exceptionDate, $this->startDate->getTimeZone());
+
+ }
+
+ }
+
+ }
+
+ }
+
+ /**
+ * Returns the current item in the list
+ *
+ * @return DateTime
+ */
+ public function current() {
+
+ if (!$this->valid()) return null;
+ return clone $this->currentDate;
+
+ }
+
+ /**
+ * This method returns the startdate for the current iteration of the
+ * event.
+ *
+ * @return DateTime
+ */
+ public function getDtStart() {
+
+ if (!$this->valid()) return null;
+ return clone $this->currentDate;
+
+ }
+
+ /**
+ * This method returns the enddate for the current iteration of the
+ * event.
+ *
+ * @return DateTime
+ */
+ public function getDtEnd() {
+
+ if (!$this->valid()) return null;
+ $dtEnd = clone $this->currentDate;
+ $dtEnd->add( $this->startDate->diff( $this->endDate ) );
+ return clone $dtEnd;
+
+ }
+
+ /**
+ * Returns a VEVENT object with the updated start and end date.
+ *
+ * Any recurrence information is removed, and this function may return an
+ * 'overridden' event instead.
+ *
+ * This method always returns a cloned instance.
+ *
+ * @return Component\VEvent
+ */
+ public function getEventObject() {
+
+ if ($this->currentOverriddenEvent) {
+ return clone $this->currentOverriddenEvent;
+ }
+ $event = clone $this->baseEvent;
+ unset($event->RRULE);
+ unset($event->EXDATE);
+ unset($event->RDATE);
+ unset($event->EXRULE);
+
+ $event->DTSTART->setDateTime($this->getDTStart(), $event->DTSTART->getDateType());
+ if (isset($event->DTEND)) {
+ $event->DTEND->setDateTime($this->getDtEnd(), $event->DTSTART->getDateType());
+ }
+ if ($this->counter > 0) {
+ $event->{'RECURRENCE-ID'} = (string)$event->DTSTART;
+ }
+
+ return $event;
+
+ }
+
+ /**
+ * Returns the current item number
+ *
+ * @return int
+ */
+ public function key() {
+
+ return $this->counter;
+
+ }
+
+ /**
+ * Whether or not there is a 'next item'
+ *
+ * @return bool
+ */
+ public function valid() {
+
+ if (!is_null($this->count)) {
+ return $this->counter < $this->count;
+ }
+ if (!is_null($this->until) && $this->currentDate > $this->until) {
+
+ // Need to make sure there's no overridden events past the
+ // until date.
+ foreach($this->overriddenEvents as $overriddenEvent) {
+
+ if ($overriddenEvent->DTSTART->getDateTime() >= $this->currentDate) {
+
+ return true;
+ }
+ }
+ return false;
+ }
+ return true;
+
+ }
+
+ /**
+ * Resets the iterator
+ *
+ * @return void
+ */
+ public function rewind() {
+
+ $this->currentDate = clone $this->startDate;
+ $this->counter = 0;
+
+ }
+
+ /**
+ * This method allows you to quickly go to the next occurrence after the
+ * specified date.
+ *
+ * Note that this checks the current 'endDate', not the 'stardDate'. This
+ * means that if you forward to January 1st, the iterator will stop at the
+ * first event that ends *after* January 1st.
+ *
+ * @param DateTime $dt
+ * @return void
+ */
+ public function fastForward(\DateTime $dt) {
+
+ while($this->valid() && $this->getDTEnd() <= $dt) {
+ $this->next();
+ }
+
+ }
+
+ /**
+ * Returns true if this recurring event never ends.
+ *
+ * @return bool
+ */
+ public function isInfinite() {
+
+ return !$this->count && !$this->until;
+
+ }
+
+ /**
+ * Goes on to the next iteration
+ *
+ * @return void
+ */
+ public function next() {
+
+ $previousStamp = $this->currentDate->getTimeStamp();
+
+ // Finding the next overridden event in line, and storing that for
+ // later use.
+ $overriddenEvent = null;
+ $overriddenDate = null;
+ $this->currentOverriddenEvent = null;
+
+ foreach($this->overriddenEvents as $index=>$event) {
+ if ($index > $previousStamp) {
+ $overriddenEvent = $event;
+ $overriddenDate = clone $event->DTSTART->getDateTime();
+ break;
+ }
+ }
+
+ // If we have a stored 'next date', we will use that.
+ if ($this->nextDate) {
+ if (!$overriddenDate || $this->nextDate < $overriddenDate) {
+ $this->currentDate = $this->nextDate;
+ $currentStamp = $this->currentDate->getTimeStamp();
+ $this->nextDate = null;
+ } else {
+ $this->currentDate = clone $overriddenDate;
+ $this->currentOverriddenEvent = $overriddenEvent;
+ }
+ $this->counter++;
+ return;
+ }
+
+ while(true) {
+
+ // Otherwise, we find the next event in the normal RRULE
+ // sequence.
+ switch($this->frequency) {
+
+ case 'hourly' :
+ $this->nextHourly();
+ break;
+
+ case 'daily' :
+ $this->nextDaily();
+ break;
+
+ case 'weekly' :
+ $this->nextWeekly();
+ break;
+
+ case 'monthly' :
+ $this->nextMonthly();
+ break;
+
+ case 'yearly' :
+ $this->nextYearly();
+ break;
+
+ }
+ $currentStamp = $this->currentDate->getTimeStamp();
+
+
+ // Checking exception dates
+ foreach($this->exceptionDates as $exceptionDate) {
+ if ($this->currentDate == $exceptionDate) {
+ $this->counter++;
+ continue 2;
+ }
+ }
+ foreach($this->overriddenDates as $check) {
+ if ($this->currentDate == $check) {
+ continue 2;
+ }
+ }
+ break;
+
+ }
+
+
+
+ // Is the date we have actually higher than the next overiddenEvent?
+ if ($overriddenDate && $this->currentDate > $overriddenDate) {
+ $this->nextDate = clone $this->currentDate;
+ $this->currentDate = clone $overriddenDate;
+ $this->currentOverriddenEvent = $overriddenEvent;
+ $this->handledOverridden++;
+ }
+ $this->counter++;
+
+
+ /*
+ * If we have overridden events left in the queue, but our counter is
+ * running out, we should grab one of those.
+ */
+ if (!is_null($overriddenEvent) && !is_null($this->count) && count($this->overriddenEvents) - $this->handledOverridden >= ($this->count - $this->counter)) {
+
+ $this->currentOverriddenEvent = $overriddenEvent;
+ $this->currentDate = clone $overriddenDate;
+ $this->handledOverridden++;
+
+ }
+
+ }
+
+ /**
+ * Does the processing for advancing the iterator for hourly frequency.
+ *
+ * @return void
+ */
+ protected function nextHourly() {
+
+ if (!$this->byHour) {
+ $this->currentDate->modify('+' . $this->interval . ' hours');
+ return;
+ }
+ }
+
+ /**
+ * Does the processing for advancing the iterator for daily frequency.
+ *
+ * @return void
+ */
+ protected function nextDaily() {
+
+ if (!$this->byHour && !$this->byDay) {
+ $this->currentDate->modify('+' . $this->interval . ' days');
+ return;
+ }
+
+ if (isset($this->byHour)) {
+ $recurrenceHours = $this->getHours();
+ }
+
+ if (isset($this->byDay)) {
+ $recurrenceDays = $this->getDays();
+ }
+
+ do {
+
+ if ($this->byHour) {
+ if ($this->currentDate->format('G') == '23') {
+ // to obey the interval rule
+ $this->currentDate->modify('+' . $this->interval-1 . ' days');
+ }
+
+ $this->currentDate->modify('+1 hours');
+
+ } else {
+ $this->currentDate->modify('+' . $this->interval . ' days');
+
+ }
+
+ // Current day of the week
+ $currentDay = $this->currentDate->format('w');
+
+ // Current hour of the day
+ $currentHour = $this->currentDate->format('G');
+
+ } while (($this->byDay && !in_array($currentDay, $recurrenceDays)) || ($this->byHour && !in_array($currentHour, $recurrenceHours)));
+
+ }
+
+ /**
+ * Does the processing for advancing the iterator for weekly frequency.
+ *
+ * @return void
+ */
+ protected function nextWeekly() {
+
+ if (!$this->byHour && !$this->byDay) {
+ $this->currentDate->modify('+' . $this->interval . ' weeks');
+ return;
+ }
+
+ if ($this->byHour) {
+ $recurrenceHours = $this->getHours();
+ }
+
+ if ($this->byDay) {
+ $recurrenceDays = $this->getDays();
+ }
+
+ // First day of the week:
+ $firstDay = $this->dayMap[$this->weekStart];
+
+ do {
+
+ if ($this->byHour) {
+ $this->currentDate->modify('+1 hours');
+ } else {
+ $this->currentDate->modify('+1 days');
+ }
+
+ // Current day of the week
+ $currentDay = (int) $this->currentDate->format('w');
+
+ // Current hour of the day
+ $currentHour = (int) $this->currentDate->format('G');
+
+ // We need to roll over to the next week
+ if ($currentDay === $firstDay && (!$this->byHour || $currentHour == '0')) {
+ $this->currentDate->modify('+' . $this->interval-1 . ' weeks');
+
+ // We need to go to the first day of this week, but only if we
+ // are not already on this first day of this week.
+ if($this->currentDate->format('w') != $firstDay) {
+ $this->currentDate->modify('last ' . $this->dayNames[$this->dayMap[$this->weekStart]]);
+ }
+ }
+
+ // We have a match
+ } while (($this->byDay && !in_array($currentDay, $recurrenceDays)) || ($this->byHour && !in_array($currentHour, $recurrenceHours)));
+ }
+
+ /**
+ * Does the processing for advancing the iterator for monthly frequency.
+ *
+ * @return void
+ */
+ protected function nextMonthly() {
+
+ $currentDayOfMonth = $this->currentDate->format('j');
+ if (!$this->byMonthDay && !$this->byDay) {
+
+ // If the current day is higher than the 28th, rollover can
+ // occur to the next month. We Must skip these invalid
+ // entries.
+ if ($currentDayOfMonth < 29) {
+ $this->currentDate->modify('+' . $this->interval . ' months');
+ } else {
+ $increase = 0;
+ do {
+ $increase++;
+ $tempDate = clone $this->currentDate;
+ $tempDate->modify('+ ' . ($this->interval*$increase) . ' months');
+ } while ($tempDate->format('j') != $currentDayOfMonth);
+ $this->currentDate = $tempDate;
+ }
+ return;
+ }
+
+ while(true) {
+
+ $occurrences = $this->getMonthlyOccurrences();
+
+ foreach($occurrences as $occurrence) {
+
+ // The first occurrence thats higher than the current
+ // day of the month wins.
+ if ($occurrence > $currentDayOfMonth) {
+ break 2;
+ }
+
+ }
+
+ // If we made it all the way here, it means there were no
+ // valid occurrences, and we need to advance to the next
+ // month.
+ $this->currentDate->modify('first day of this month');
+ $this->currentDate->modify('+ ' . $this->interval . ' months');
+
+ // This goes to 0 because we need to start counting at hte
+ // beginning.
+ $currentDayOfMonth = 0;
+
+ }
+
+ $this->currentDate->setDate($this->currentDate->format('Y'), $this->currentDate->format('n'), $occurrence);
+
+ }
+
+ /**
+ * Does the processing for advancing the iterator for yearly frequency.
+ *
+ * @return void
+ */
+ protected function nextYearly() {
+
+ $currentMonth = $this->currentDate->format('n');
+ $currentYear = $this->currentDate->format('Y');
+ $currentDayOfMonth = $this->currentDate->format('j');
+
+ // No sub-rules, so we just advance by year
+ if (!$this->byMonth) {
+
+ // Unless it was a leap day!
+ if ($currentMonth==2 && $currentDayOfMonth==29) {
+
+ $counter = 0;
+ do {
+ $counter++;
+ // Here we increase the year count by the interval, until
+ // we hit a date that's also in a leap year.
+ //
+ // We could just find the next interval that's dividable by
+ // 4, but that would ignore the rule that there's no leap
+ // year every year that's dividable by a 100, but not by
+ // 400. (1800, 1900, 2100). So we just rely on the datetime
+ // functions instead.
+ $nextDate = clone $this->currentDate;
+ $nextDate->modify('+ ' . ($this->interval*$counter) . ' years');
+ } while ($nextDate->format('n')!=2);
+ $this->currentDate = $nextDate;
+
+ return;
+
+ }
+
+ // The easiest form
+ $this->currentDate->modify('+' . $this->interval . ' years');
+ return;
+
+ }
+
+ $currentMonth = $this->currentDate->format('n');
+ $currentYear = $this->currentDate->format('Y');
+ $currentDayOfMonth = $this->currentDate->format('j');
+
+ $advancedToNewMonth = false;
+
+ // If we got a byDay or getMonthDay filter, we must first expand
+ // further.
+ if ($this->byDay || $this->byMonthDay) {
+
+ while(true) {
+
+ $occurrences = $this->getMonthlyOccurrences();
+
+ foreach($occurrences as $occurrence) {
+
+ // The first occurrence that's higher than the current
+ // day of the month wins.
+ // If we advanced to the next month or year, the first
+ // occurrence is always correct.
+ if ($occurrence > $currentDayOfMonth || $advancedToNewMonth) {
+ break 2;
+ }
+
+ }
+
+ // If we made it here, it means we need to advance to
+ // the next month or year.
+ $currentDayOfMonth = 1;
+ $advancedToNewMonth = true;
+ do {
+
+ $currentMonth++;
+ if ($currentMonth>12) {
+ $currentYear+=$this->interval;
+ $currentMonth = 1;
+ }
+ } while (!in_array($currentMonth, $this->byMonth));
+
+ $this->currentDate->setDate($currentYear, $currentMonth, $currentDayOfMonth);
+
+ }
+
+ // If we made it here, it means we got a valid occurrence
+ $this->currentDate->setDate($currentYear, $currentMonth, $occurrence);
+ return;
+
+ } else {
+
+ // These are the 'byMonth' rules, if there are no byDay or
+ // byMonthDay sub-rules.
+ do {
+
+ $currentMonth++;
+ if ($currentMonth>12) {
+ $currentYear+=$this->interval;
+ $currentMonth = 1;
+ }
+ } while (!in_array($currentMonth, $this->byMonth));
+ $this->currentDate->setDate($currentYear, $currentMonth, $currentDayOfMonth);
+
+ return;
+
+ }
+
+ }
+
+ /**
+ * Returns all the occurrences for a monthly frequency with a 'byDay' or
+ * 'byMonthDay' expansion for the current month.
+ *
+ * The returned list is an array of integers with the day of month (1-31).
+ *
+ * @return array
+ */
+ protected function getMonthlyOccurrences() {
+
+ $startDate = clone $this->currentDate;
+
+ $byDayResults = array();
+
+ // Our strategy is to simply go through the byDays, advance the date to
+ // that point and add it to the results.
+ if ($this->byDay) foreach($this->byDay as $day) {
+
+ $dayName = $this->dayNames[$this->dayMap[substr($day,-2)]];
+
+ // Dayname will be something like 'wednesday'. Now we need to find
+ // all wednesdays in this month.
+ $dayHits = array();
+
+ $checkDate = clone $startDate;
+ $checkDate->modify('first day of this month');
+ $checkDate->modify($dayName);
+
+ do {
+ $dayHits[] = $checkDate->format('j');
+ $checkDate->modify('next ' . $dayName);
+ } while ($checkDate->format('n') === $startDate->format('n'));
+
+ // So now we have 'all wednesdays' for month. It is however
+ // possible that the user only really wanted the 1st, 2nd or last
+ // wednesday.
+ if (strlen($day)>2) {
+ $offset = (int)substr($day,0,-2);
+
+ if ($offset>0) {
+ // It is possible that the day does not exist, such as a
+ // 5th or 6th wednesday of the month.
+ if (isset($dayHits[$offset-1])) {
+ $byDayResults[] = $dayHits[$offset-1];
+ }
+ } else {
+
+ // if it was negative we count from the end of the array
+ $byDayResults[] = $dayHits[count($dayHits) + $offset];
+ }
+ } else {
+ // There was no counter (first, second, last wednesdays), so we
+ // just need to add the all to the list).
+ $byDayResults = array_merge($byDayResults, $dayHits);
+
+ }
+
+ }
+
+ $byMonthDayResults = array();
+ if ($this->byMonthDay) foreach($this->byMonthDay as $monthDay) {
+
+ // Removing values that are out of range for this month
+ if ($monthDay > $startDate->format('t') ||
+ $monthDay < 0-$startDate->format('t')) {
+ continue;
+ }
+ if ($monthDay>0) {
+ $byMonthDayResults[] = $monthDay;
+ } else {
+ // Negative values
+ $byMonthDayResults[] = $startDate->format('t') + 1 + $monthDay;
+ }
+ }
+
+ // If there was just byDay or just byMonthDay, they just specify our
+ // (almost) final list. If both were provided, then byDay limits the
+ // list.
+ if ($this->byMonthDay && $this->byDay) {
+ $result = array_intersect($byMonthDayResults, $byDayResults);
+ } elseif ($this->byMonthDay) {
+ $result = $byMonthDayResults;
+ } else {
+ $result = $byDayResults;
+ }
+ $result = array_unique($result);
+ sort($result, SORT_NUMERIC);
+
+ // The last thing that needs checking is the BYSETPOS. If it's set, it
+ // means only certain items in the set survive the filter.
+ if (!$this->bySetPos) {
+ return $result;
+ }
+
+ $filteredResult = array();
+ foreach($this->bySetPos as $setPos) {
+
+ if ($setPos<0) {
+ $setPos = count($result)-($setPos+1);
+ }
+ if (isset($result[$setPos-1])) {
+ $filteredResult[] = $result[$setPos-1];
+ }
+ }
+
+ sort($filteredResult, SORT_NUMERIC);
+ return $filteredResult;
+
+ }
+
+ protected function getHours()
+ {
+ $recurrenceHours = array();
+ foreach($this->byHour as $byHour) {
+ $recurrenceHours[] = $byHour;
+ }
+
+ return $recurrenceHours;
+ }
+
+ protected function getDays()
+ {
+ $recurrenceDays = array();
+ foreach($this->byDay as $byDay) {
+
+ // The day may be preceeded with a positive (+n) or
+ // negative (-n) integer. However, this does not make
+ // sense in 'weekly' so we ignore it here.
+ $recurrenceDays[] = $this->dayMap[substr($byDay,-2)];
+
+ }
+
+ return $recurrenceDays;
+ }
+}
+