public function intersect(TrieCollection $collection)
{
$keys = $collection->getKeys();
$this->entries = array_values(array_filter($this->entries, function ($value) use($keys) {
return in_array($value->key, $keys);
}));
return $this->sortKeys();
}
/**
* Fetch all child nodes with a value below a specified node
*
* @param TrieNode $trieNode Node that is our start point for the retrieval
* @param string $searchPrefix The prefix that we're searching for
* @param string $prefix Full Key for the requested start point
* @return TrieCollection[] Collection of TrieEntry key/value pairs for all child nodes with a value
*/
protected function getAllChildren(TrieNode $trieNode, $searchPrefix, $prefix)
{
$collection = new TrieCollection();
if ($trieNode->value !== null) {
if (strpos($prefix, $searchPrefix) === 0) {
foreach ($trieNode->value as $value) {
if ($value instanceof TrieEntry) {
$collection->add(clone $value);
} else {
$collection->add(new TrieEntry($value, $prefix));
}
}
}
}
if (isset($trieNode->children)) {
foreach ($trieNode->children as $characters => $trie) {
$collection->merge($this->getAllChildren($trie, $searchPrefix, $prefix . $characters));
}
}
return $collection;
}