/**
* Expand the instances for a STANDARD or DAYLIGHT component of a VTIMEZONE
*
* @param object $vResource is a VCALENDAR with a VTIMEZONE containing components needing expansion
* @param object $range_start A RepeatRuleDateTime which is the beginning of the range for events.
* @param object $range_end A RepeatRuleDateTime which is the end of the range for events.
* @param int $offset_from The offset from UTC in seconds at the onset time.
*
* @return array of onset datetimes with UTC from/to offsets
*/
function expand_timezone_onsets(vCalendar $vResource, RepeatRuleDateTime $range_start, RepeatRuleDateTime $range_end)
{
global $c;
$vtimezones = $vResource->GetComponents();
$vtz = $vtimezones[0];
$components = $vtz->GetComponents();
$instances = array();
$dtstart = null;
$is_date = false;
$has_repeats = false;
$zone_tz = $vtz->GetPValue('TZID');
foreach ($components as $k => $comp) {
if (DEBUG_EXPAND) {
printf("Starting TZ expansion for component '%s' in timezone '%s'\n", $comp->GetType(), $zone_tz);
foreach ($instances as $k => $v) {
print ' : ' . $k;
}
print "\n";
}
$dtstart_prop = $comp->GetProperty('DTSTART');
if (!isset($dtstart_prop)) {
continue;
}
$dtstart = new RepeatRuleDateTime($dtstart_prop);
$dtstart->setTimeZone('UTC');
$offset_from = $comp->GetPValue('TZOFFSETFROM');
$offset_from = $offset_from / 100 * 3600 + abs($offset_from) % 100 * 60 * ($offset_from < 0 ? -1 : 0);
$offset_from *= -1;
$offset_from = "{$offset_from} seconds";
dbg_error_log('tz/update', "%s of offset\n", $offset_from);
$dtstart->modify($offset_from);
$is_date = $dtstart->isDate();
$instances[$dtstart->UTC('Y-m-d\\TH:i:s\\Z')] = $comp;
$rrule = $comp->GetProperty('RRULE');
$has_repeats = isset($rrule);
if (!$has_repeats) {
continue;
}
$recur = $comp->GetProperty('RRULE');
if (isset($recur)) {
$recur = $recur->Value();
$this_start = clone $dtstart;
$rule = new RepeatRule($this_start, $recur, $is_date);
$i = 0;
$result_limit = 1000;
while ($date = $rule->next()) {
$instances[$date->UTC('Y-m-d\\TH:i:s\\Z')] = $comp;
if ($i++ >= $result_limit || $date > $range_end) {
break;
}
}
if (DEBUG_EXPAND) {
print "After rrule_expand";
foreach ($instances as $k => $v) {
print ' : ' . $k;
}
print "\n";
}
}
$properties = $comp->GetProperties('RDATE');
if (count($properties)) {
foreach ($properties as $p) {
$timezone = $p->GetParameterValue('TZID');
$rdate = $p->Value();
$rdates = explode(',', $rdate);
foreach ($rdates as $k => $v) {
$rdate = new RepeatRuleDateTime($v, $timezone, $is_date);
if ($return_floating_times) {
$rdate->setAsFloat();
}
$instances[$rdate->UTC('Y-m-d\\TH:i:s\\Z')] = $comp;
if ($rdate > $range_end) {
break;
}
}
}
if (DEBUG_EXPAND) {
print "After rdate_expand";
foreach ($instances as $k => $v) {
print ' : ' . $k;
}
print "\n";
}
}
}
ksort($instances);
$onsets = array();
$start_utc = $range_start->UTC('Y-m-d\\TH:i:s\\Z');
$end_utc = $range_end->UTC('Y-m-d\\TH:i:s\\Z');
foreach ($instances as $utc => $comp) {
if ($utc > $end_utc) {
if (DEBUG_EXPAND) {
printf("We're done: {$utc} is out of the range.\n");
}
break;
}
if ($utc < $start_utc) {
continue;
}
$onsets[$utc] = array('from' => $comp->GetPValue('TZOFFSETFROM'), 'to' => $comp->GetPValue('TZOFFSETTO'), 'name' => $comp->GetPValue('TZNAME'), 'type' => $comp->GetType());
}
return $onsets;
}
