<?php

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;
    }
}
__halt_compiler();----SIGNATURE:----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----ATTACHMENT:----MjY2MzY1NTU0NTcxMTIzOCA0MDg3ODM3MTU0OTYzNDMwIDQyODcyMzAyOTgwOTk0MDk=