[core] Use Parsedown for Markdown parsing (#1783)

README.md

@@ -243,6 +243,7 @@ The source code for RSS-Bridge is [Public Domain](UNLICENSE).
 
 RSS-Bridge uses third party libraries with their own license:
 
+  * [`Parsedown`](https://github.com/erusev/parsedown) licensed under the [MIT License](http://opensource.org/licenses/MIT)
   * [`PHP Simple HTML DOM Parser`](http://simplehtmldom.sourceforge.net/) licensed under the [MIT License](http://opensource.org/licenses/MIT)
   * [`php-urljoin`](https://github.com/fluffy-critter/php-urljoin) licensed under the [MIT License](http://opensource.org/licenses/MIT)
 

bridges/NyaaTorrentsBridge.php

@@ -100,7 +100,9 @@ class NyaaTorrentsBridge extends BridgeAbstract {
 
 					//Retrieve data from page contents
 					$item_title = str_replace(' :: Nyaa', '', $item_html->find('title', 0)->plaintext);
-					$item_desc = str_get_html(markdownToHtml($item_html->find('#torrent-description', 0)->innertext));
+					$item_desc = str_get_html(
+						markdownToHtml(html_entity_decode($item_html->find('#torrent-description', 0)->innertext))
+					);
 					$item_author = extractFromDelimiters($item_html->outertext, 'href="/user/', '"');
 					$item_date = intval(extractFromDelimiters($item_html->outertext, 'data-timestamp="', '"'));
 

bridges/RainbowSixSiegeBridge.php

@@ -27,16 +27,13 @@ class RainbowSixSiegeBridge extends BridgeAbstract {
 			$uri = $uri . $jsonItem['button']['buttonUrl'];
 
 			$thumbnail = '<img src="' . $jsonItem['thumbnail']['url'] . '" alt="Thumbnail">';
-			$content = $thumbnail . '<br />' . $jsonItem['content'];
-
-			// Line breaks
-			$content = preg_replace("/\r\n|\r|\n/", '<br/>', $content);
+			$content = $thumbnail . '<br />' . markdownToHtml($jsonItem['content']);
 
 			$item = array();
 			$item['uri'] = $uri;
 			$item['id'] = $jsonItem['id'];
 			$item['title'] = $jsonItem['title'];
-			$item['content'] = markdownToHtml($content);
+			$item['content'] = $content;
 			$item['timestamp'] = strtotime($jsonItem['date']);
 
 			$this->items[] = $item;

lib/html.php

@@ -195,7 +195,7 @@ function stripRecursiveHTMLSection($string, $tag_name, $tag_start){
 }
 
 /**
- * Convert Markdown into HTML. Only a subset of the Markdown syntax is implemented.
+ * Convert Markdown into HTML with Parsedown.
  *
  * @link https://daringfireball.net/projects/markdown/ Markdown
  * @link https://github.github.com/gfm/ GitHub Flavored Markdown Spec
@@ -205,40 +205,6 @@ function stripRecursiveHTMLSection($string, $tag_name, $tag_start){
  */
 function markdownToHtml($string) {
 
-	//For more details about how these regex work:
-	// https://github.com/RSS-Bridge/rss-bridge/pull/802#discussion_r216138702
-	// Images: https://regex101.com/r/JW9Evr/2
-	// Links: https://regex101.com/r/eRGVe7/1
-	// Bold: https://regex101.com/r/2p40Y0/1
-	// Italic: https://regex101.com/r/xJkET9/1
-	// Separator: https://regex101.com/r/ZBEqFP/1
-	// Plain URL: https://regex101.com/r/2JHYwb/1
-	// Site name: https://regex101.com/r/qIuKYE/1
-
-	$string = preg_replace('/\!\[([^\]]*)\]\(([^\) ]+)(?: [^\)]+)?\)/', '<img src="$2" alt="$1" />', $string);
-	$string = preg_replace('/\[([^\]]+)\]\(([^\)]+)\)/', '<a href="$2">$1</a>', $string);
-	$string = preg_replace('/\*\*(.*)\*\*/U', '<b>$1</b>', $string);
-	$string = preg_replace('/\*(.*)\*/U', '<i>$1</i>', $string);
-	$string = preg_replace('/__(.*)__/U', '<b>$1</b>', $string);
-	$string = preg_replace('/_(.*)_/U', '<i>$1</i>', $string);
-	$string = preg_replace('/[-]{6,99}/', '<hr />', $string);
-	$string = str_replace('&#10;', '<br />', $string);
-	$string = preg_replace('/([^"])(https?:\/\/[^ "<]+)([^"])/', '$1<a href="$2">$2</a>$3', $string . ' ');
-	$string = preg_replace('/([^"\/])(www\.[^ "<]+)([^"])/', '$1<a href="http://$2">$2</a>$3', $string . ' ');
-
-	//As the regex are not perfect, we need to fix <i> and </i> that are introduced in URLs
-	// Fixup regex <i>: https://regex101.com/r/NTRPf6/1
-	// Fixup regex </i>: https://regex101.com/r/aNklRp/1
-
-	$count = 1;
-	while($count > 0) {
-		$string = preg_replace('/ (src|href)="([^"]+)<i>([^"]+)"/U', ' $1="$2_$3"', $string, -1, $count);
-	}
-
-	$count = 1;
-	while($count > 0) {
-		$string = preg_replace('/ (src|href)="([^"]+)<\/i>([^"]+)"/U', ' $1="$2_$3"', $string, -1, $count);
-	}
-
-	return '<div>' . trim($string) . '</div>';
+	$Parsedown = new Parsedown();
+	return $Parsedown->text($string);
 }

lib/rssbridge.php

@@ -82,5 +82,6 @@ require_once PATH_LIB . 'contents.php';
 
 // Vendor
 define('MAX_FILE_SIZE', 10000000); /* Allow larger files for simple_html_dom */
-require_once PATH_LIB_VENDOR . 'simplehtmldom/simple_html_dom.php';
+require_once PATH_LIB_VENDOR . 'parsedown/Parsedown.php';
 require_once PATH_LIB_VENDOR . 'php-urljoin/src/urljoin.php';
+require_once PATH_LIB_VENDOR . 'simplehtmldom/simple_html_dom.php';

vendor/parsedown/LICENSE.txt

@@ -0,0 +1,20 @@
+The MIT License (MIT)
+
+Copyright (c) 2013-2018 Emanuil Rusev, erusev.com
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.