leilukin-tumbleblog/includes/lib/xenocrat/markdown/block/FrontMatterTrait.php

81 lines
1.9 KiB
PHP

<?php
/**
* @copyright Copyright 2024 Daniel Pimley
* @license https://github.com/xenocrat/chyrp-markdown/blob/master/LICENSE
* @link https://github.com/xenocrat/chyrp-markdown#readme
*/
namespace xenocrat\markdown\block;
/**
* Adds front matter blocks.
*/
trait FrontMatterTrait
{
/**
* @var bool - Render front matter as a code block.
*/
public $renderFrontMatter = true;
/**
* Identify a line as the beginning of a front matter block.
*/
protected function identifyFrontMatter($line): bool
{
return (
preg_match('/^ {0,3};{3,}[^;]*$/', $line)
|| preg_match('/^ {0,3}\-{3,}[^\-]*$/', $line)
|| preg_match('/^ {0,3}\+{3,}[^\+]*$/', $line)
);
}
/**
* Consume lines for a front matter block.
*/
protected function consumeFrontMatter($lines, $current): array
{
$indent = strspn($lines[$current], ' ');
$line = substr($lines[$current], $indent);
$mw = strspn($line, $line[0]);
$fence = substr($line, 0, $mw);
$language = trim(substr($line, $mw));
$content = [];
// Consume until end fence...
for ($i = $current + 1, $count = count($lines); $i < $count; $i++) {
$line = $lines[$i];
$leadingSpaces = strspn($line, ' ');
if (
$leadingSpaces > 3
|| strspn(ltrim($line), $fence[0]) < $mw
|| !str_ends_with(rtrim($line), $fence[0])
) {
if ($indent > 0 && $leadingSpaces > 0) {
if ($leadingSpaces < $indent) {
$line = ltrim($line);
} else {
$line = substr($line, $indent);
}
}
$content[] = $line;
} else {
break;
}
}
$block = [
'code',
'content' => implode("\n", $content),
];
if ($language !== '') {
if (preg_match('/^[^ ]+/', $language, $match)) {
$block['language'] = $this->unEscapeBackslash($match[0]);
}
}
return [($this->renderFrontMatter) ? $block : false, $i];
}
abstract protected function renderCode($block);
abstract protected function unEscapeBackslash($text);
}