<?php
namespace Sabre\VObject\Recur;
use DateTimeInterface;
use DateTimeImmutable;
use Iterator;
use Sabre\VObject\DateTimeParser;
use Sabre\VObject\InvalidDataException;
use Sabre\VObject\Property;
/**
* RRuleParser.
*
* This class receives an RRULE string, and allows you to iterate to get a list
* of dates in that recurrence.
*
* For instance, passing: FREQ=DAILY;LIMIT=5 will cause the iterator to contain
* 5 items, one for each day.
*
* @copyright Copyright (C) fruux GmbH (https://fruux.com/)
* @author Evert Pot (http://evertpot.com/)
* @license http://sabre.io/license/ Modified BSD License
*/
class RRuleIterator implements Iterator {
/**
* Creates the Iterator.
*
* @param string|array $rrule
* @param DateTimeInterface $start
*/
function __construct($rrule, DateTimeInterface $start) {
$this->startDate = $start;
$this->parseRRule($rrule);
$this->currentDate = clone $this->startDate;
}
/* Implementation of the Iterator interface {{{ */
function current() {
if (!$this->valid()) return;
return clone $this->currentDate;
}
/**
* Returns the current item number.
*
* @return int
*/
function key() {
return $this->counter;
}
/**
* Returns whether the current item is a valid item for the recurrence
* iterator. This will return false if we've gone beyond the UNTIL or COUNT
* statements.
*
* @return bool
*/
function valid() {
if (!is_null($this->count)) {
return $this->counter < $this->count;
}
return is_null($this->until) || $this->currentDate <= $this->until;
}
/**
* Resets the iterator.
*
* @return void
*/
function rewind() {
$this->currentDate = clone $this->startDate;
$this->counter = 0;
}
/**
* Goes on to the next iteration.
*
* @return void
*/
function next() {
// Otherwise, we find the next event in the normal RRULE
// sequence.
switch ($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;
}
$this->counter++;
}
/* End of Iterator implementation }}} */
/**
* Returns true if this recurring event never ends.
*
* @return bool
*/
function isInfinite() {
return !$this->count && !$this->until;
}
/**
* This method allows you to quickly go to the next occurrence after the
* specified date.
*
* @param DateTimeInterface $dt
*
* @return void
*/
function fastForward(DateTimeInterface $dt) {
while ($this->valid() && $this->currentDate < $dt) {
$this->next();
}
}
/**
* The reference start date/time for the rrule.
*
* All calculations are based on this initial date.
*
* @var DateTimeInterface
*/
protected $startDate;
/**
* The date of the current iteration. You can get this by calling
* ->current().
*
* @var DateTimeInterface
*/
protected $currentDate;
/**
* Frequency is one of: secondly, minutely, hourly, daily, weekly, monthly,
* yearly.
*
* @var string
*/
protected $frequency;
/**
* The number of recurrences, or 'null' if infinitely recurring.
*
* @var int
*/
protected $count;
/**
* The interval.
*
* If for example frequency is set to daily, interval = 2 would mean every
* 2 days.
*
* @var int
*/
protected $interval = 1;
/**
* The last instance of this recurrence, inclusively.
*
* @var DateTimeInterface|null
*/
protected $until;
/**
* Which seconds to recur.
*
* This is an array of integers (between 0 and 60)
*
* @var array
*/
protected $bySecond;
/**
* Which minutes to recur.
*
* This is an array of integers (between 0 and 59)
*
* @var array
*/
protected $byMinute;
/**
* Which hours to recur.
*
* This is an array of integers (between 0 and 23)
*
* @var array
*/
protected $byHour;
/**
* The current item in the list.
*
* You can get this number with the key() method.
*
* @var int
*/
protected $counter = 0;
/**
* 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
*/
protected $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
*/
protected $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
*/
protected $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
*/
protected $byWeekNo;
/**
* Which months to recur.
*
* This is an array of integers from 1 to 12.
*
* @var array
*/
protected $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
*/
protected $bySetPos;
/**
* When the week starts.
*
* @var string
*/
protected $weekStart = 'MO';
/* Functions that advance the iterator {{{ */
/**
* Does the processing for advancing the iterator for hourly frequency.
*
* @return void
*/
protected function nextHourly() {
$this->currentDate = $this->currentDate->modify('+' . $this->interval . ' hours');
}
/**
* Does the processing for advancing the iterator for daily frequency.
*
* @return void
*/
protected function nextDaily() {
if (!$this->byHour && !$this->byDay) {
$this->currentDate = $this->currentDate->modify('+' . $this->interval . ' days');
return;
}
if (!empty($this->byHour)) {
$recurrenceHours = $this->getHours();
}
if (!empty($this->byDay)) {
$recurrenceDays = $this->getDays();
}
if (!empty($this->byMonth)) {
$recurrenceMonths = $this->getMonths();
}
do {
if ($this->byHour) {
if ($this->currentDate->format('G') == '23') {
// to obey the interval rule
$this->currentDate = $this->currentDate->modify('+' . $this->interval - 1 . ' days');
}
$this->currentDate = $this->currentDate->modify('+1 hours');
} else {
$this->currentDate = $this->currentDate->modify('+' . $this->interval . ' days');
}
// Current month of the year
$currentMonth = $this->currentDate->format('n');
// 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, $recurrenceHours)) ||
($this->byMonth && !in_array($currentMonth, $recurrenceMonths))
);
}
/**
* Does the processing for advancing the iterator for weekly frequency.
*
* @return void
*/
protected function nextWeekly() {
if (!$this->byHour && !$this->byDay) {
$this->currentDate = $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 = $this->currentDate->modify('+1 hours');
} else {
$this->currentDate = $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 = $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 = $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 = $this->currentDate->modify('+' . $this->interval . ' months');
} else {
$increase = 0;
do {
$increase++;
$tempDate = clone $this->currentDate;
$tempDate = $tempDate->modify('+ ' . ($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 line does not currently work in hhvm. Temporary workaround
// follows:
// $this->currentDate->modify('first day of this month');
$this->currentDate = new DateTimeImmutable($this->currentDate->format('Y-m-1 H:i:s'), $this->currentDate->getTimezone());
// end of workaround
$this->currentDate = $this->currentDate->modify('+ ' . $this->interval . ' months');
// This goes to 0 because we need to start counting at the
// beginning.
$currentDayOfMonth = 0;
}
$this->currentDate = $this->currentDate->setDate(
(int)$this->currentDate->format('Y'),
(int)$this->currentDate->format('n'),
(int)$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 = $this->currentDate->format('j');
// No sub-rules, so we just advance by year
if (empty($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 = $nextDate->modify('+ ' . ($this->interval * $counter) . ' years');
} while ($nextDate->format('n') != 2);
$this->currentDate = $nextDate;
return;
}
// The easiest form
$this->currentDate = $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 = $this->currentDate->setDate(
(int)$currentYear,
(int)$currentMonth,
(int)$currentDayOfMonth
);
}
// If we made it here, it means we got a valid occurrence
$this->currentDate = $this->currentDate->setDate(
(int)$currentYear,
(int)$currentMonth,
(int)$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 = $this->currentDate->setDate(
(int)$currentYear,
(int)$currentMonth,
(int)$currentDayOfMonth
);
return;
}
}
/* }}} */
/**
* This method receives a string from an RRULE property, and populates this
* class with all the values.
*
* @param string|array $rrule
*
* @return void
*/
protected function parseRRule($rrule) {
if (is_string($rrule)) {
$rrule = Property\ICalendar\Recur::stringToArray($rrule);
}
foreach ($rrule as $key => $value) {
$key = strtoupper($key);
switch ($key) {
case 'FREQ' :
$value = strtolower($value);
if (!in_array(
$value,
['secondly', 'minutely', 'hourly', 'daily', 'weekly', 'monthly', 'yearly']
)) {
throw new InvalidDataException('Unknown value for FREQ=' . strtoupper($value));
}
$this->frequency = $value;
break;
case 'UNTIL' :
$this->until = DateTimeParser::parse($value, $this->startDate->getTimezone());
// In some cases events are generated with an UNTIL=
// parameter before the actual start of the event.
//
// Not sure why this is happening. We assume that the
// intention was that the event only recurs once.
//
// So we are modifying the parameter so our code doesn't
// break.
if ($this->until < $this->startDate) {
$this->until = $this->startDate;
}
break;
case 'INTERVAL' :
// No break
case 'COUNT' :
$val = (int)$value;
if ($val < 1) {
throw new InvalidDataException(strtoupper($key) . ' in RRULE must be a positive integer!');
}
$key = strtolower($key);
$this->$key = $val;
break;
case 'BYSECOND' :
$this->bySecond = (array)$value;
break;
case 'BYMINUTE' :
$this->byMinute = (array)$value;
break;
case 'BYHOUR' :
$this->byHour = (array)$value;
break;
case 'BYDAY' :
$value = (array)$value;
foreach ($value as $part) {
if (!preg_match('#^ (-|\+)? ([1-5])? (MO|TU|WE|TH|FR|SA|SU) $# xi', $part)) {
throw new InvalidDataException('Invalid part in BYDAY clause: ' . $part);
}
}
$this->byDay = $value;
break;
case 'BYMONTHDAY' :
$this->byMonthDay = (array)$value;
break;
case 'BYYEARDAY' :
$this->byYearDay = (array)$value;
break;
case 'BYWEEKNO' :
$this->byWeekNo = (array)$value;
break;
case 'BYMONTH' :
$this->byMonth = (array)$value;
break;
case 'BYSETPOS' :
$this->bySetPos = (array)$value;
break;
case 'WKST' :
$this->weekStart = strtoupper($value);
break;
default:
throw new InvalidDataException('Not supported: ' . strtoupper($key));
}
}
}
/**
* Mappings between the day number and english day name.
*
* @var array
*/
protected $dayNames = [
0 => 'Sunday',
1 => 'Monday',
2 => 'Tuesday',
3 => 'Wednesday',
4 => 'Thursday',
5 => 'Friday',
6 => 'Saturday',
];
/**
* 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;
$byDayResults = [];
// Our strategy is to simply go through the byDays, advance the date to
// that point and add it to the results.
if ($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 = [];
// workaround for missing 'first day of the month' support in hhvm
$checkDate = new \DateTime($startDate->format('Y-m-1'));
// workaround modify always advancing the date even if the current day is a $dayName in hhvm
if ($checkDate->format('l') !== $dayName) {
$checkDate = $checkDate->modify($dayName);
}
do {
$dayHits[] = $checkDate->format('j');
$checkDate = $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
// might not exist, fx. -5th tuesday
if (isset($dayHits[count($dayHits) + $offset])) {
$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);
}
}
$byMonthDayResults = [];
if ($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;
}
$filteredResult = [];
foreach ($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;
}
/**
* Simple mapping from iCalendar day names to day numbers.
*
* @var array
*/
protected $dayMap = [
'SU' => 0,
'MO' => 1,
'TU' => 2,
'WE' => 3,
'TH' => 4,
'FR' => 5,
'SA' => 6,
];
protected function getHours() {
$recurrenceHours = [];
foreach ($this->byHour as $byHour) {
$recurrenceHours[] = $byHour;
}
return $recurrenceHours;
}
protected function getDays() {
$recurrenceDays = [];
foreach ($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;
}
protected function getMonths() {
$recurrenceMonths = [];
foreach ($this->byMonth as $byMonth) {
$recurrenceMonths[] = $byMonth;
}
return $recurrenceMonths;
}
}
