This class is the central point to fetch timezone information from the
timezone (Olson) database, parse it, cache it, and generate VTIMEZONE
objects.
Usage:
$tz = new Horde_Timezone();
$tz->getZone('America/New_York')->toVtimezone()->exportVcalendar();
Documentation on the database file formats can be found at
ftp://ftp.iana.org/tz/tz-how-to.html
/**
* Adds rules from this ruleset to a VTIMEZONE component.
*
* @param Horde_Icalendar_Vtimezone $tz A VTIMEZONE component.
* @param string $tzid The timezone ID of the component.
* @param string $name A timezone name abbreviation.
* May contain a placeholder that is
* replaced the Rules' "Letter(s)"
* entry.
* @param array $startOffset An offset hash describing the
* base offset of a timezone.
* @param Horde_Date $start Start of the period to add rules
* for.
* @param Horde_Date $end End of the period to add rules
* for.
*/
public function addRules(Horde_Icalendar_Vtimezone $tz, $tzid, $name, $startOffset, Horde_Date $start, Horde_Date $end = null)
{
$offset = $startOffset;
foreach ($this->_rules as $rule) {
$year = $rule[3];
if ($year[0] == 'o') {
// TO is "only"
$rule[3] = $rule[2];
}
if ($rule[3][0] != 'm' && $rule[3] < $start->year) {
// TO is not maximum and is before the searched period
continue;
}
if ($end && $rule[2][0] != 'm' && $rule[2] > $end->year) {
// FROM is not "minimum" and is after the searched period
break;
}
if ($rule[2][0] != 'm' && $rule[2] < $start->year) {
$rule[2] = $start->year;
}
if ($rule[8] == 0) {
$component = new Horde_Icalendar_Standard();
$component->setAttribute('TZOFFSETFROM', $offset);
$component->setAttribute('TZOFFSETTO', $startOffset);
$offset = $startOffset;
} else {
$component = new Horde_Icalendar_Daylight();
$component->setAttribute('TZOFFSETFROM', $offset);
$offset = $this->_getOffset($startOffset, $rule[8]);
$component->setAttribute('TZOFFSETTO', $offset);
}
$month = Horde_Timezone::getMonth($rule[5]);
// Retrieve time of rule start.
preg_match('/(\\d+)(?::(\\d+))?(?::(\\d+))?(w|s|u)?/', $rule[7], $match);
if (!isset($match[2])) {
$match[2] = 0;
}
if ($rule[2] == $rule[3] && preg_match('/^\\d+$/', $rule[6])) {
// Rule lasts only for a single year and starts on a specific
// date.
$rdate = new Horde_Date(array('year' => $rule[2], 'month' => Horde_Timezone::getMonth($rule[5]), 'mday' => $rule[6], 'hour' => $match[1], 'min' => $match[2], 'sec' => 0));
$component->setAttribute('DTSTART', $rdate);
} elseif (substr($rule[6], 0, 4) == 'last') {
// Rule starts on the last of a certain weekday of the month.
$weekday = $this->_weekdays[substr($rule[6], 4, 3)];
$last = new Horde_Date(array('year' => $rule[2], 'month' => $month, 'mday' => Horde_Date_Utils::daysInMonth($month, $rule[2]), 'hour' => $match[1], 'min' => $match[2], 'sec' => 0));
while ($last->dayOfWeek() != $weekday) {
$last->mday--;
}
$component->setAttribute('DTSTART', $last);
if ($rule[3][0] == 'm') {
$until = '';
} else {
$last = new Horde_Date(array('year' => $rule[3], 'month' => $month, 'mday' => Horde_Date_Utils::daysInMonth($month, $rule[2]), 'hour' => $match[1], 'min' => $match[2], 'sec' => 0), $tzid);
while ($last->dayOfWeek() != $weekday) {
$last->mday--;
}
$last->setTimezone('UTC');
$until = ';UNTIL=' . $last->format('Ymd\\THIs') . 'Z';
}
$component->setAttribute('RRULE', 'FREQ=YEARLY;BYDAY=-1' . Horde_String::upper(substr($rule[6], 4, 2)) . ';BYMONTH=' . $month . $until);
} elseif (strpos($rule[6], '>=')) {
// Rule starts on a certain weekday after a certain day of
// month.
list($weekday, $day) = explode('>=', $rule[6]);
$weekdayInt = $this->_weekdays[substr($weekday, 0, 3)];
$first = new Horde_Date(array('year' => $rule[2], 'month' => $month, 'mday' => $day, 'hour' => $match[1], 'min' => $match[2], 'sec' => 0));
while ($first->dayOfWeek() != $weekdayInt) {
$first->mday++;
}
$component->setAttribute('DTSTART', $first);
if ($rule[3][0] == 'm') {
$until = '';
} else {
$last = new Horde_Date(array('year' => $rule[3], 'month' => $month, 'mday' => $day, 'hour' => $match[1], 'min' => $match[2], 'sec' => 0), $tzid);
while ($last->dayOfWeek() != $weekday) {
$last->mday++;
}
$last->setTimezone('UTC');
$until = ';UNTIL=' . $last->format('Ymd\\THIs') . 'Z';
}
for ($days = array(), $i = $day, $lastDay = min(Horde_Date_Utils::daysInMonth($month, $rule[2]), $i + 6); $day > 1 && $i <= $lastDay; $i++) {
$days[] = $i;
}
$component->setAttribute('RRULE', 'FREQ=YEARLY;BYMONTH=' . $month . ($days ? ';BYMONTHDAY=' . implode(',', $days) : '') . ';BYDAY=1' . Horde_String::upper(substr($weekday, 0, 2)) . $until);
} elseif (strpos($rule[6], '<=')) {
// Rule starts on a certain weekday before a certain day of
// month.
list($weekday, $day) = explode('>=', $rule[6]);
$weekdayInt = $this->_weekdays[substr($weekday, 0, 3)];
$last = new Horde_Date(array('year' => $rule[2], 'month' => $month, 'mday' => $day, 'hour' => $match[1], 'min' => $match[2], 'sec' => 0));
while ($last->dayOfWeek() != $weekdayInt) {
$last->mday--;
}
$component->setAttribute('DTSTART', $last);
if ($rule[3][0] == 'm') {
$until = '';
} else {
$last = new Horde_Date(array('year' => $rule[3], 'month' => $month, 'mday' => $day, 'hour' => $match[1], 'min' => $match[2], 'sec' => 0), $tzid);
while ($last->dayOfWeek() != $weekday) {
$last->mday--;
}
$last->setTimezone('UTC');
$until = ';UNTIL=' . $last->format('Ymd\\THIs') . 'Z';
}
for ($days = array(), $i = 1; $i <= $day; $i++) {
$days[] = $i;
}
$component->setAttribute('RRULE', 'FREQ=YEARLY;BYMONTH=' . $month . ';BYMONTHDAY=' . implode(',', $days) . ';BYDAY=-1' . Horde_String::upper(substr($weekday, 0, 2)) . $until);
}
$component->setAttribute('TZNAME', sprintf($name, $rule[9]));
$tz->addComponent($component);
}
}
/**
* Finds a date matching a rule definition.
*
* @param array $rule A rule definition hash from addRules().
* @param integer $year A year when the rule should be applied.
*
* @return Horde_Date The first matching date.
*/
protected function _getFirstMatch($rule, $year)
{
$month = Horde_Timezone::getMonth($rule[5]);
if (preg_match('/^\\d+$/', $rule[6])) {
// Rule starts on a specific date.
$date = new Horde_Date(array('year' => $year, 'month' => $month, 'mday' => $rule[6]));
} elseif (substr($rule[6], 0, 4) == 'last') {
// Rule starts on the last of a certain weekday of the month.
$weekday = $this->_weekdays[substr($rule[6], 4, 3)];
$date = new Horde_Date(array('year' => $year, 'month' => $month, 'mday' => Horde_Date_Utils::daysInMonth($month, $rule[2])));
while ($date->dayOfWeek() != $weekday) {
$date->mday--;
}
} elseif (strpos($rule[6], '>=')) {
// Rule starts on a certain weekday after a certain day of month.
list($weekday, $day) = explode('>=', $rule[6]);
$weekdayInt = $this->_weekdays[substr($weekday, 0, 3)];
$date = new Horde_Date(array('year' => $year, 'month' => $month, 'mday' => $day));
while ($date->dayOfWeek() != $weekdayInt) {
$date->mday++;
}
} elseif (strpos($rule[6], '<=')) {
// Rule starts on a certain weekday before a certain day of month.
list($weekday, $day) = explode('>=', $rule[6]);
$weekdayInt = $this->_weekdays[substr($weekday, 0, 3)];
$date = new Horde_Date(array('year' => $year, 'month' => $month, 'mday' => $day));
while ($date->dayOfWeek() != $weekdayInt) {
$date->mday--;
}
} else {
throw new Horde_Timezone_Exception('Cannot parse rule ' . $rule[6]);
}
return $date;
}
/**
* Calculates a date from the date columns of a Zone line.
*
* @param integer $line A line number.
*
* @return Horde_Date The date of this line.
*/
protected function _getDate($line)
{
$date = array_slice($this->_info[$line], 3);
$year = $date[0];
$month = isset($date[1]) ? Horde_Timezone::getMonth($date[1]) : 1;
$day = isset($date[2]) ? $date[2] : 1;
$time = isset($date[3]) && $date[3] != '-' ? $date[3] : 0;
preg_match('/(\\d+)(?::(\\d+))?(?::(\\d+))?(w|s|u)?/', $time, $match);
if (!isset($match[2])) {
$match[2] = 0;
}
if (!isset($match[3])) {
$match[3] = 0;
}
switch (substr($time, -1)) {
case 's':
// Standard time. Not sure what to do about this.
break;
case 'u':
// UTC, add offset.
$offset = $this->_getOffset($line);
$factor = $offset['ahead'] ? 1 : -1;
$match[1] += $factor * $offset['hour'];
$match[2] += $factor * $offset['minute'];
case 'w':
default:
// Wall time, nothing to do.
break;
}
return new Horde_Date(array('year' => $year, 'month' => $month, 'mday' => $day, 'hour' => $match[1], 'min' => $match[2], 'sec' => $match[3]));
}
public function __construct($zone)
{
parent::__construct();
$this->_zone = $zone;
}
