/**
* Expand the event instances for an RRULE property
*
* @param object $dtstart A RepeatRuleDateTime which is the master dtstart
* @param string $property RDATE or EXDATE, depending...
* @param array $component A vComponent which is a VEVENT, VTODO or VJOURNAL
* @param array $range_end A date after which we care less about expansion
*
* @return array An array keyed on the UTC dates, referring to the component
*/
function rrule_expand($dtstart, $property, $component, $range_end)
{
$expansion = array();
$recur = $component->GetProperty($property);
if (!isset($recur)) {
return $expansion;
}
$recur = $recur->Value();
$this_start = $component->GetProperty('DTSTART');
if (isset($this_start)) {
$timezone = $this_start->GetParameterValue('TZID');
$this_start = new RepeatRuleDateTime($this_start->Value(), $timezone);
} else {
$this_start = clone $dtstart;
}
// print_r( $this_start );
// printf( "RRULE: %s\n", $recur );
$rule = new RepeatRule($this_start, $recur);
$i = 0;
$result_limit = 1000;
while ($date = $rule->next()) {
// printf( "[%3d] %s\n", $i, $date->UTC() );
$expansion[$date->UTC()] = $component;
if ($i++ >= $result_limit || $date > $range_end) {
break;
}
}
// print_r( $expansion );
return $expansion;
}
