BookStack/app/Entities/Tools/Markdown/HtmlToMarkdown.php
2022-03-22 14:56:51 +00:00

95 lines
4.5 KiB
PHP

<?php
namespace BookStack\Entities\Tools\Markdown;
use League\HTMLToMarkdown\Converter\BlockquoteConverter;
use League\HTMLToMarkdown\Converter\CodeConverter;
use League\HTMLToMarkdown\Converter\CommentConverter;
use League\HTMLToMarkdown\Converter\DivConverter;
use League\HTMLToMarkdown\Converter\EmphasisConverter;
use League\HTMLToMarkdown\Converter\HardBreakConverter;
use League\HTMLToMarkdown\Converter\HeaderConverter;
use League\HTMLToMarkdown\Converter\HorizontalRuleConverter;
use League\HTMLToMarkdown\Converter\ImageConverter;
use League\HTMLToMarkdown\Converter\LinkConverter;
use League\HTMLToMarkdown\Converter\ListBlockConverter;
use League\HTMLToMarkdown\Converter\ListItemConverter;
use League\HTMLToMarkdown\Converter\PreformattedConverter;
use League\HTMLToMarkdown\Converter\TextConverter;
use League\HTMLToMarkdown\Environment;
use League\HTMLToMarkdown\HtmlConverter;
class HtmlToMarkdown
{
protected $html;
public function __construct(string $html)
{
$this->html = $html;
}
/**
* Run the conversion.
*/
public function convert(): string
{
$converter = new HtmlConverter($this->getConverterEnvironment());
$html = $this->prepareHtml($this->html);
return $converter->convert($html);
}
/**
* Run any pre-processing to the HTML to clean it up manually before conversion.
*/
protected function prepareHtml(string $html): string
{
// Carriage returns can cause whitespace issues in output
$html = str_replace("\r\n", "\n", $html);
// Attributes on the pre tag can cause issues with conversion
return preg_replace('/<pre .*?>/', '<pre>', $html);
}
/**
* Get the HTML to Markdown customized environment.
* Extends the default provided environment with some BookStack specific tweaks.
*/
protected function getConverterEnvironment(): Environment
{
$environment = new Environment([
'header_style' => 'atx', // Set to 'atx' to output H1 and H2 headers as # Header1 and ## Header2
'suppress_errors' => true, // Set to false to show warnings when loading malformed HTML
'strip_tags' => false, // Set to true to strip tags that don't have markdown equivalents. N.B. Strips tags, not their content. Useful to clean MS Word HTML output.
'strip_placeholder_links' => false, // Set to true to remove <a> that doesn't have href.
'bold_style' => '**', // DEPRECATED: Set to '__' if you prefer the underlined style
'italic_style' => '*', // DEPRECATED: Set to '_' if you prefer the underlined style
'remove_nodes' => '', // space-separated list of dom nodes that should be removed. example: 'meta style script'
'hard_break' => false, // Set to true to turn <br> into `\n` instead of ` \n`
'list_item_style' => '-', // Set the default character for each <li> in a <ul>. Can be '-', '*', or '+'
'preserve_comments' => false, // Set to true to preserve comments, or set to an array of strings to preserve specific comments
'use_autolinks' => false, // Set to true to use simple link syntax if possible. Will always use []() if set to false
'table_pipe_escape' => '\|', // Replacement string for pipe characters inside markdown table cells
'table_caption_side' => 'top', // Set to 'top' or 'bottom' to show <caption> content before or after table, null to suppress
]);
$environment->addConverter(new BlockquoteConverter());
$environment->addConverter(new CodeConverter());
$environment->addConverter(new CommentConverter());
$environment->addConverter(new DivConverter());
$environment->addConverter(new EmphasisConverter());
$environment->addConverter(new HardBreakConverter());
$environment->addConverter(new HeaderConverter());
$environment->addConverter(new HorizontalRuleConverter());
$environment->addConverter(new ImageConverter());
$environment->addConverter(new LinkConverter());
$environment->addConverter(new ListBlockConverter());
$environment->addConverter(new ListItemConverter());
$environment->addConverter(new CustomParagraphConverter());
$environment->addConverter(new PreformattedConverter());
$environment->addConverter(new TextConverter());
$environment->addConverter(new CheckboxConverter());
return $environment;
}
}