1<?php
2
3/*
4 * This file is part of the league/commonmark package.
5 *
6 * (c) Colin O'Dell <colinodell@gmail.com>
7 * (c) 2015 Martin Hasoň <martin.hason@gmail.com>
8 *
9 * For the full copyright and license information, please view the LICENSE
10 * file that was distributed with this source code.
11 */
12
13declare(strict_types=1);
14
15namespace League\CommonMark\Extension\Attributes\Util;
16
17use League\CommonMark\Node\Node;
18use League\CommonMark\Parser\Cursor;
19use League\CommonMark\Util\RegexHelper;
20
21/**
22 * @internal
23 */
24final class AttributesHelper
25{
26    private const SINGLE_ATTRIBUTE = '\s*([.#][_a-z0-9-]+|' . RegexHelper::PARTIAL_ATTRIBUTENAME . RegexHelper::PARTIAL_ATTRIBUTEVALUESPEC . ')\s*';
27    private const ATTRIBUTE_LIST   = '/^{:?(' . self::SINGLE_ATTRIBUTE . ')+}/i';
28
29    /**
30     * @return array<string, mixed>
31     */
32    public static function parseAttributes(Cursor $cursor): array
33    {
34        $state = $cursor->saveState();
35        $cursor->advanceToNextNonSpaceOrNewline();
36
37        // Quick check to see if we might have attributes
38        if ($cursor->getCharacter() !== '{') {
39            $cursor->restoreState($state);
40
41            return [];
42        }
43
44        // Attempt to match the entire attribute list expression
45        // While this is less performant than checking for '{' now and '}' later, it simplifies
46        // matching individual attributes since they won't need to look ahead for the closing '}'
47        // while dealing with the fact that attributes can technically contain curly braces.
48        // So we'll just match the start and end braces up front.
49        $attributeExpression = $cursor->match(self::ATTRIBUTE_LIST);
50        if ($attributeExpression === null) {
51            $cursor->restoreState($state);
52
53            return [];
54        }
55
56        // Trim the leading '{' or '{:' and the trailing '}'
57        $attributeExpression = \ltrim(\substr($attributeExpression, 1, -1), ':');
58        $attributeCursor     = new Cursor($attributeExpression);
59
60        /** @var array<string, mixed> $attributes */
61        $attributes = [];
62        while ($attribute = \trim((string) $attributeCursor->match('/^' . self::SINGLE_ATTRIBUTE . '/i'))) {
63            if ($attribute[0] === '#') {
64                $attributes['id'] = \substr($attribute, 1);
65
66                continue;
67            }
68
69            if ($attribute[0] === '.') {
70                $attributes['class'][] = \substr($attribute, 1);
71
72                continue;
73            }
74
75            /** @psalm-suppress PossiblyUndefinedArrayOffset */
76            [$name, $value] = \explode('=', $attribute, 2);
77
78            $first = $value[0];
79            $last  = \substr($value, -1);
80            if (($first === '"' && $last === '"') || ($first === "'" && $last === "'") && \strlen($value) > 1) {
81                $value = \substr($value, 1, -1);
82            }
83
84            if (\strtolower(\trim($name)) === 'class') {
85                foreach (\array_filter(\explode(' ', \trim($value))) as $class) {
86                    $attributes['class'][] = $class;
87                }
88            } else {
89                $attributes[\trim($name)] = \trim($value);
90            }
91        }
92
93        if (isset($attributes['class'])) {
94            $attributes['class'] = \implode(' ', (array) $attributes['class']);
95        }
96
97        return $attributes;
98    }
99
100    /**
101     * @param Node|array<string, mixed> $attributes1
102     * @param Node|array<string, mixed> $attributes2
103     *
104     * @return array<string, mixed>
105     */
106    public static function mergeAttributes($attributes1, $attributes2): array
107    {
108        $attributes = [];
109        foreach ([$attributes1, $attributes2] as $arg) {
110            if ($arg instanceof Node) {
111                $arg = $arg->data->get('attributes');
112            }
113
114            /** @var array<string, mixed> $arg */
115            $arg = (array) $arg;
116            if (isset($arg['class'])) {
117                if (\is_string($arg['class'])) {
118                    $arg['class'] = \array_filter(\explode(' ', \trim($arg['class'])));
119                }
120
121                foreach ($arg['class'] as $class) {
122                    $attributes['class'][] = $class;
123                }
124
125                unset($arg['class']);
126            }
127
128            $attributes = \array_merge($attributes, $arg);
129        }
130
131        if (isset($attributes['class'])) {
132            $attributes['class'] = \implode(' ', $attributes['class']);
133        }
134
135        return $attributes;
136    }
137}
138