1<?php
2
3declare(strict_types=1);
4
5/*
6 * This file is part of the league/commonmark package.
7 *
8 * (c) Colin O'Dell <colinodell@gmail.com>
9 *
10 * For the full copyright and license information, please view the LICENSE
11 * file that was distributed with this source code.
12 */
13
14namespace League\CommonMark\Extension\HeadingPermalink;
15
16use League\CommonMark\Environment\EnvironmentAwareInterface;
17use League\CommonMark\Environment\EnvironmentInterface;
18use League\CommonMark\Event\DocumentParsedEvent;
19use League\CommonMark\Extension\CommonMark\Node\Block\Heading;
20use League\CommonMark\Node\NodeIterator;
21use League\CommonMark\Node\RawMarkupContainerInterface;
22use League\CommonMark\Node\StringContainerHelper;
23use League\CommonMark\Normalizer\TextNormalizerInterface;
24use League\Config\ConfigurationInterface;
25use League\Config\Exception\InvalidConfigurationException;
26
27/**
28 * Searches the Document for Heading elements and adds HeadingPermalinks to each one
29 */
30final class HeadingPermalinkProcessor implements EnvironmentAwareInterface
31{
32    public const INSERT_BEFORE = 'before';
33    public const INSERT_AFTER  = 'after';
34    public const INSERT_NONE   = 'none';
35
36    /** @psalm-readonly-allow-private-mutation */
37    private TextNormalizerInterface $slugNormalizer;
38
39    /** @psalm-readonly-allow-private-mutation */
40    private ConfigurationInterface $config;
41
42    public function setEnvironment(EnvironmentInterface $environment): void
43    {
44        $this->config         = $environment->getConfiguration();
45        $this->slugNormalizer = $environment->getSlugNormalizer();
46    }
47
48    public function __invoke(DocumentParsedEvent $e): void
49    {
50        $min            = (int) $this->config->get('heading_permalink/min_heading_level');
51        $max            = (int) $this->config->get('heading_permalink/max_heading_level');
52        $applyToHeading = (bool) $this->config->get('heading_permalink/apply_id_to_heading');
53        $idPrefix       = (string) $this->config->get('heading_permalink/id_prefix');
54        $slugLength     = (int) $this->config->get('slug_normalizer/max_length');
55        $headingClass   = (string) $this->config->get('heading_permalink/heading_class');
56
57        if ($idPrefix !== '') {
58            $idPrefix .= '-';
59        }
60
61        foreach ($e->getDocument()->iterator(NodeIterator::FLAG_BLOCKS_ONLY) as $node) {
62            if ($node instanceof Heading && $node->getLevel() >= $min && $node->getLevel() <= $max) {
63                $this->addHeadingLink($node, $slugLength, $idPrefix, $applyToHeading, $headingClass);
64            }
65        }
66    }
67
68    private function addHeadingLink(Heading $heading, int $slugLength, string $idPrefix, bool $applyToHeading, string $headingClass): void
69    {
70        $text = StringContainerHelper::getChildText($heading, [RawMarkupContainerInterface::class]);
71        $slug = $this->slugNormalizer->normalize($text, [
72            'node' => $heading,
73            'length' => $slugLength,
74        ]);
75
76        if ($applyToHeading) {
77            $heading->data->set('attributes/id', $idPrefix . $slug);
78        }
79
80        if ($headingClass !== '') {
81            $heading->data->append('attributes/class', $headingClass);
82        }
83
84        $headingLinkAnchor = new HeadingPermalink($slug);
85
86        switch ($this->config->get('heading_permalink/insert')) {
87            case self::INSERT_BEFORE:
88                $heading->prependChild($headingLinkAnchor);
89
90                return;
91            case self::INSERT_AFTER:
92                $heading->appendChild($headingLinkAnchor);
93
94                return;
95            case self::INSERT_NONE:
96                return;
97            default:
98                throw new InvalidConfigurationException("Invalid configuration value for heading_permalink/insert; expected 'before', 'after', or 'none'");
99        }
100    }
101}
102