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 * Original code based on the CommonMark JS reference parser (http://bitly.com/commonmark-js)
11 *  - (c) John MacFarlane
12 *
13 * For the full copyright and license information, please view the LICENSE
14 * file that was distributed with this source code.
15 */
16
17namespace League\CommonMark\Extension\SmartPunct;
18
19use League\CommonMark\Node\Inline\Text;
20use League\CommonMark\Parser\Inline\InlineParserInterface;
21use League\CommonMark\Parser\Inline\InlineParserMatch;
22use League\CommonMark\Parser\InlineParserContext;
23
24final class DashParser implements InlineParserInterface
25{
26    private const EN_DASH = '–';
27    private const EM_DASH = '—';
28
29    public function getMatchDefinition(): InlineParserMatch
30    {
31        return InlineParserMatch::regex('(?<!-)(-{2,})');
32    }
33
34    public function parse(InlineParserContext $inlineContext): bool
35    {
36        $count = $inlineContext->getFullMatchLength();
37        $inlineContext->getCursor()->advanceBy($count);
38
39        $enCount = 0;
40        $emCount = 0;
41        if ($count % 3 === 0) { // If divisible by 3, use all em dashes
42            $emCount = (int) ($count / 3);
43        } elseif ($count % 2 === 0) { // If divisible by 2, use all en dashes
44            $enCount = (int) ($count / 2);
45        } elseif ($count % 3 === 2) { // If 2 extra dashes, use en dash for last 2; em dashes for rest
46            $emCount = (int) (($count - 2) / 3);
47            $enCount = 1;
48        } else { // Use en dashes for last 4 hyphens; em dashes for rest
49            $emCount = (int) (($count - 4) / 3);
50            $enCount = 2;
51        }
52
53        $inlineContext->getContainer()->appendChild(new Text(
54            \str_repeat(self::EM_DASH, $emCount) . \str_repeat(self::EN_DASH, $enCount)
55        ));
56
57        return true;
58    }
59}
60