81 lines
2.1 KiB
PHP
81 lines
2.1 KiB
PHP
<?php
|
|
|
|
declare(strict_types=1);
|
|
|
|
/*
|
|
* This file is part of the league/commonmark package.
|
|
*
|
|
* (c) Colin O'Dell <colinodell@gmail.com>
|
|
*
|
|
* Original code based on the CommonMark JS reference parser (https://bitly.com/commonmark-js)
|
|
* - (c) John MacFarlane
|
|
*
|
|
* For the full copyright and license information, please view the LICENSE
|
|
* file that was distributed with this source code.
|
|
*/
|
|
|
|
namespace League\CommonMark\Node;
|
|
|
|
use League\CommonMark\Node\Block\AbstractBlock;
|
|
|
|
final class NodeWalker
|
|
{
|
|
/** @psalm-readonly */
|
|
private Node $root;
|
|
|
|
/** @psalm-readonly-allow-private-mutation */
|
|
private ?Node $current = null;
|
|
|
|
/** @psalm-readonly-allow-private-mutation */
|
|
private bool $entering;
|
|
|
|
public function __construct(Node $root)
|
|
{
|
|
$this->root = $root;
|
|
$this->current = $this->root;
|
|
$this->entering = true;
|
|
}
|
|
|
|
/**
|
|
* Returns an event which contains node and entering flag
|
|
* (entering is true when we enter a Node from a parent or sibling,
|
|
* and false when we reenter it from child)
|
|
*/
|
|
public function next(): ?NodeWalkerEvent
|
|
{
|
|
$current = $this->current;
|
|
$entering = $this->entering;
|
|
if ($current === null) {
|
|
return null;
|
|
}
|
|
|
|
if ($entering && ($current instanceof AbstractBlock || $current->hasChildren())) {
|
|
if ($current->firstChild()) {
|
|
$this->current = $current->firstChild();
|
|
$this->entering = true;
|
|
} else {
|
|
$this->entering = false;
|
|
}
|
|
} elseif ($current === $this->root) {
|
|
$this->current = null;
|
|
} elseif ($current->next() === null) {
|
|
$this->current = $current->parent();
|
|
$this->entering = false;
|
|
} else {
|
|
$this->current = $current->next();
|
|
$this->entering = true;
|
|
}
|
|
|
|
return new NodeWalkerEvent($current, $entering);
|
|
}
|
|
|
|
/**
|
|
* Resets the iterator to resume at the specified node
|
|
*/
|
|
public function resumeAt(Node $node, bool $entering = true): void
|
|
{
|
|
$this->current = $node;
|
|
$this->entering = $entering;
|
|
}
|
|
}
|