/**
* Recursively walks over all tree nodes and call visitors for them
*
* @param TreeNodeInterface $node
* @return mixed
* @throws NodeDataLoadException
*/
private function visitNodes(TreeNodeInterface $node)
{
try {
// Collects values from children
$data = $node->getValue();
if ($node->hasChildren()) {
$data = [];
foreach ($node as $key => $item) {
$data[$key] = $this->visitNodes($item);
}
}
// Call visitors for the current node and data collected from children
$visitors = $this->visitors->getVisitors($node);
foreach ($visitors as $visitor) {
$visitResult = $visitor->visit($node, $data);
if ($visitResult !== null) {
$data = $visitResult;
}
}
return $data;
} catch (\Exception $exception) {
throw new NodeDataLoadException('Error loading data from ' . $node->getPath(), $exception);
}
}
/**
* @inheritdoc
*/
public function visit(TreeNodeInterface $node, &$data)
{
return (string) crc32($node->getValue());
}
