/**
* THREAD=REFS sorting implementation (based on provided index)
*
* @param rcube_result_index $index Sorted message identifiers
*/
public function sort($index)
{
$this->sort_order = $index->get_parameters('ORDER');
if (empty($this->raw_data)) {
return;
}
// when sorting search result it's good to make the index smaller
if ($index->count() != $this->count_messages()) {
$index->filter($this->get());
}
$result = array_fill_keys($index->get(), null);
$datalen = strlen($this->raw_data);
$start = 0;
// Here we're parsing raw_data twice, we want only one big array
// in memory at a time
// Assign roots
while (($pos = @strpos($this->raw_data, self::SEPARATOR_ELEMENT, $start)) || $start < $datalen && ($pos = $datalen)) {
$len = $pos - $start;
$elem = substr($this->raw_data, $start, $len);
$start = $pos + 1;
$items = explode(self::SEPARATOR_ITEM, $elem);
$root = (int) array_shift($items);
if ($root) {
$result[$root] = $root;
foreach ($items as $item) {
list($lv, $id) = explode(self::SEPARATOR_LEVEL, $item);
$result[$id] = $root;
}
}
}
// get only unique roots
$result = array_filter($result);
// make sure there are no nulls
$result = array_unique($result);
// Re-sort raw data
$result = array_fill_keys($result, null);
$start = 0;
while (($pos = @strpos($this->raw_data, self::SEPARATOR_ELEMENT, $start)) || $start < $datalen && ($pos = $datalen)) {
$len = $pos - $start;
$elem = substr($this->raw_data, $start, $len);
$start = $pos + 1;
$npos = strpos($elem, self::SEPARATOR_ITEM);
$root = (int) ($npos ? substr($elem, 0, $npos) : $elem);
$result[$root] = $elem;
}
$this->raw_data = implode(self::SEPARATOR_ELEMENT, $result);
}
