<?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:----NzAxMDE3MDM4MzI2ODY3MSAyNjgwNDQ1MzkzNTMzOTAwIDc0OTc5NTE4ODA4MTEwNDc=