From 12bdbaaba8b8d247a8507468ac4c9872120e0f1f Mon Sep 17 00:00:00 2001
From: Michael <heluecht@pirati.ca>
Date: Sat, 24 Feb 2024 11:01:34 +0000
Subject: [PATCH 1/2] OEmbed: Complete cleanup

---
 src/Content/OEmbed.php      | 229 ++++++------------------------------
 src/Content/Text/BBCode.php |  16 +--
 src/Model/Post/Media.php    |   2 +-
 src/Module/Oembed.php       |  74 ------------
 src/Util/ParseUrl.php       |  54 +--------
 static/defaults.config.php  |   4 -
 static/routes.config.php    |   5 -
 7 files changed, 50 insertions(+), 334 deletions(-)
 delete mode 100644 src/Module/Oembed.php

diff --git a/src/Content/OEmbed.php b/src/Content/OEmbed.php
index 445c52ced0..d89cfca3e1 100644
--- a/src/Content/OEmbed.php
+++ b/src/Content/OEmbed.php
@@ -22,8 +22,6 @@
 namespace Friendica\Content;
 
 use DOMDocument;
-use DOMNode;
-use DOMText;
 use DOMXPath;
 use Exception;
 use Friendica\Core\Cache\Enum\Duration;
@@ -32,10 +30,10 @@ use Friendica\Core\Renderer;
 use Friendica\Database\Database;
 use Friendica\Database\DBA;
 use Friendica\DI;
+use Friendica\Model\Post;
 use Friendica\Network\HTTPClient\Client\HttpClientAccept;
 use Friendica\Util\DateTimeFormat;
 use Friendica\Util\Network;
-use Friendica\Util\ParseUrl;
 use Friendica\Util\Proxy;
 use Friendica\Util\Strings;
 
@@ -49,32 +47,15 @@ use Friendica\Util\Strings;
  */
 class OEmbed
 {
-	/**
-	 * Callback for fetching URL, checking allowance and returning formatted HTML
-	 *
-	 * @param array $matches
-	 * @return string Formatted HTML
-	 */
-	public static function replaceCallback(array $matches): string
-	{
-		$embedurl = $matches[1];
-		$j = self::fetchURL($embedurl, !self::isAllowedURL($embedurl));
-		$s = self::formatObject($j);
-
-		return $s;
-	}
-
 	/**
 	 * Get data from an URL to embed its content.
 	 *
 	 * @param string $embedurl     The URL from which the data should be fetched.
-	 * @param bool   $no_rich_type If set to true rich type content won't be fetched.
-	 * @param bool   $use_parseurl Use the "ParseUrl" functionality to add additional data
 	 *
 	 * @return \Friendica\Object\OEmbed
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	public static function fetchURL(string $embedurl, bool $no_rich_type = false, bool $use_parseurl = true): \Friendica\Object\OEmbed
+	public static function fetchURL(string $embedurl): \Friendica\Object\OEmbed
 	{
 		$embedurl = trim($embedurl, '\'"');
 
@@ -119,7 +100,7 @@ class OEmbed
 							$href = str_replace(['http://www.youtube.com/', 'http://player.vimeo.com/'],
 								['https://www.youtube.com/', 'https://player.vimeo.com/'], $href);
 							$result = DI::httpClient()->fetchFull($href . '&maxwidth=' . $a->getThemeInfoValue('videowidth'));
-							if ($result->getReturnCode() === 200) {
+							if ($result->isSuccess()) {
 								$json_string = $result->getBodyString();
 								break;
 							}
@@ -156,60 +137,6 @@ class OEmbed
 			$oembed->html = str_replace(['http://www.youtube.com/', 'http://player.vimeo.com/'], ['https://www.youtube.com/', 'https://player.vimeo.com/'], $oembed->html);
 		}
 
-		// Improve the OEmbed data with data from OpenGraph, Twitter cards and other sources
-		if ($use_parseurl) {
-			$data = ParseUrl::getSiteinfoCached($embedurl, false);
-
-			if (($oembed->type == 'error') && empty($data['title']) && empty($data['text'])) {
-				return $oembed;
-			}
-
-			if ($no_rich_type || ($oembed->type == 'error')) {
-				$oembed->html = '';
-				$oembed->type = $data['type'];
-
-				if ($oembed->type == 'photo') {
-					if (!empty($data['images'])) {
-						$oembed->url = $data['images'][0]['src'];
-						$oembed->width = $data['images'][0]['width'];
-						$oembed->height = $data['images'][0]['height'];
-					} else {
-						$oembed->type = 'link';
-					}
-				}
-			}
-
-			if (!empty($data['title'])) {
-				$oembed->title = $data['title'];
-			}
-
-			if (!empty($data['text'])) {
-				$oembed->description = $data['text'];
-			}
-
-			if (!empty($data['publisher_name'])) {
-				$oembed->provider_name = $data['publisher_name'];
-			}
-
-			if (!empty($data['publisher_url'])) {
-				$oembed->provider_url = $data['publisher_url'];
-			}
-
-			if (!empty($data['author_name'])) {
-				$oembed->author_name = $data['author_name'];
-			}
-
-			if (!empty($data['author_url'])) {
-				$oembed->author_url = $data['author_url'];
-			}
-
-			if (!empty($data['images']) && ($oembed->type != 'photo')) {
-				$oembed->thumbnail_url = $data['images'][0]['src'];
-				$oembed->thumbnail_width = $data['images'][0]['width'];
-				$oembed->thumbnail_height = $data['images'][0]['height'];
-			}
-		}
-
 		Hook::callAll('oembed_fetch_url', $embedurl, $oembed);
 
 		return $oembed;
@@ -219,12 +146,20 @@ class OEmbed
 	 * Returns a formatted string from OEmbed object
 	 *
 	 * @param \Friendica\Object\OEmbed $oembed
+	 * @param int $uriid
 	 * @return string
 	 */
-	private static function formatObject(\Friendica\Object\OEmbed $oembed): string
+	private static function formatObject(\Friendica\Object\OEmbed $oembed, int $uriid): string
 	{
 		$ret = '<div class="oembed ' . $oembed->type . '">';
 
+		if (!self::isAllowedURL($oembed->url)) {
+			$oembed->html = '';
+			if ($oembed->type == 'rich') {
+				$oembed->type = 'link';
+			}
+		}
+
 		switch ($oembed->type) {
 			case 'video':
 				if ($oembed->thumbnail_url) {
@@ -241,15 +176,15 @@ class OEmbed
 						'$escapedhtml' => base64_encode($oembed->html),
 						'$tw' => $tw,
 						'$th' => $th,
-						'$turl' => $oembed->thumbnail_url,
+						'$turl' => Post\Link::getByLink($uriid, $oembed->thumbnail_url, Proxy::SIZE_MEDIUM),
 					]);
 				} else {
-					$ret = $oembed->html;
+					$ret .= Proxy::proxifyHtml($oembed->html);
 				}
 				break;
 
 			case 'photo':
-				$ret .= '<img width="' . $oembed->width . '" src="' . Proxy::proxifyUrl($oembed->url) . '">';
+				$ret .= '<img width="' . $oembed->width . '" src="' . Post\Link::getByLink($uriid, $oembed->url, Proxy::SIZE_MEDIUM) . '">';
 				break;
 
 			case 'link':
@@ -294,6 +229,14 @@ class OEmbed
 				$ret .= '<a href="' . $oembed->embed_url . '" rel="oembed">' . $oembed->embed_url . '</a>';
 			}
 			$ret .= "</h4>";
+			if ($oembed->type == 'link') {
+				if (!empty($oembed->thumbnail_url)) {
+					$ret .= '<img width="' . $oembed->width . '" src="' . Post\Link::getByLink($uriid, $oembed->thumbnail_url, Proxy::SIZE_MEDIUM) . '">';
+				}
+				if (!empty($oembed->description)) {
+					$ret .= '<p>' . $oembed->description . '</p>';
+				}
+			}
 		} elseif (!strpos($oembed->html, $oembed->embed_url)) {
 			// add <a> for html2bbcode conversion
 			$ret .= '<a href="' . $oembed->embed_url . '" rel="oembed">' . $oembed->title . '</a>';
@@ -308,51 +251,20 @@ class OEmbed
 	 * Converts BBCode to HTML code
 	 *
 	 * @param string $text
+	 * @param int    $uriid
 	 * @return string
 	 */
-	public static function BBCode2HTML(string $text): string
+	public static function BBCode2HTML(string $text, int $uriid): string
 	{
-		if (DI::config()->get('system', 'no_oembed')) {
-			return preg_replace("/\[embed\](.+?)\[\/embed\]/is", "<!-- oembed $1 --><i>" . DI::l10n()->t('Embedding disabled') . " : $1</i><!-- /oembed $1 -->", $text);
-		}
-		return preg_replace_callback("/\[embed\](.+?)\[\/embed\]/is", [self::class, 'replaceCallback'], $text);
-	}
-
-	/**
-	 * Find <span class='oembed'>..<a href='url' rel='oembed'>..</a></span>
-	 * and replace it with [embed]url[/embed]
-	 *
-	 * @param string $text
-	 * @return string
-	 */
-	public static function HTML2BBCode(string $text): string
-	{
-		// start parser only if 'oembed' is in text
-		if (strpos($text, 'oembed')) {
-			// convert non ascii chars to html entities
-			$html_text = mb_convert_encoding($text, 'HTML-ENTITIES', mb_detect_encoding($text));
-
-			// If it doesn't parse at all, just return the text.
-			$dom = new DOMDocument();
-			if (!@$dom->loadHTML($html_text)) {
-				return $text;
-			}
-			$xpath = new DOMXPath($dom);
-
-			$xattr = self::buildXPath('class', 'oembed');
-			$entries = $xpath->query("//div[$xattr]");
-
-			$xattr = "@rel='oembed'"; //oe_build_xpath("rel","oembed");
-			foreach ($entries as $e) {
-				$href = $xpath->evaluate("a[$xattr]/@href", $e)->item(0)->nodeValue;
-				if (!is_null($href)) {
-					$e->parentNode->replaceChild(new DOMText('[embed]' . $href . '[/embed]'), $e);
-				}
-			}
-			return self::getInnerHTML($dom->getElementsByTagName('body')->item(0));
-		} else {
+		if (!preg_match_all("/\[embed\](.+?)\[\/embed\]/is", $text, $matches, PREG_SET_ORDER)) {
 			return $text;
 		}
+
+		foreach ($matches as $match) {
+			$data = self::fetchURL($match[1]);
+			$text = str_replace($match[0], self::formatObject($data, $uriid), $text);
+		}
+		return $text; 
 	}
 
 	/**
@@ -362,7 +274,7 @@ class OEmbed
 	 * @return boolean
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	public static function isAllowedURL(string $url): bool
+	private static function isAllowedURL(string $url): bool
 	{
 		if (!DI::config()->get('system', 'no_oembed_rich_content')) {
 			return true;
@@ -387,12 +299,13 @@ class OEmbed
 	 * Returns a formatted HTML code from given URL and sets optional title
 	 *
 	 * @param string $url URL to fetch
-	 * @param string $title Optional title (default: what comes from OEmbed object)
+	 * @param string $title title (default: what comes from OEmbed object)
+	 * @param int    $uriid
 	 * @return string Formatted HTML
 	 */
-	public static function getHTML(string $url, string $title = ''): string
+	public static function getHTML(string $url, string $title, int $uriid): string
 	{
-		$o = self::fetchURL($url, !self::isAllowedURL($url));
+		$o = self::fetchURL($url);
 
 		if (!is_object($o) || property_exists($o, 'type') && $o->type == 'error') {
 			throw new Exception('OEmbed failed for URL: ' . $url);
@@ -402,74 +315,8 @@ class OEmbed
 			$o->title = $title;
 		}
 
-		$html = self::formatObject($o);
+		$html = self::formatObject($o, $uriid);
 
 		return $html;
 	}
-
-	/**
-	 * Generates the iframe HTML for an oembed attachment.
-	 *
-	 * Width and height are given by the remote, and are regularly too small for
-	 * the generated iframe.
-	 *
-	 * The width is entirely discarded for the actual width of the post, while fixed
-	 * height is used as a starting point before the inevitable resizing.
-	 *
-	 * Since the iframe is automatically resized on load, there are no need for ugly
-	 * and impractical scrollbars.
-	 *
-	 * @todo  This function is currently unused until someone™ adds support for a separate OEmbed domain
-	 *
-	 * @param string $src Original remote URL to embed
-	 * @param string $width
-	 * @param string $height
-	 * @return string Formatted HTML
-	 *
-	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
-	 * @see   oembed_format_object()
-	 */
-	private static function iframe(string $src, string $width, string $height): string
-	{
-		if (!$height || strstr($height, '%')) {
-			$height = '200';
-		}
-		$width = '100%';
-
-		$src = DI::baseUrl() . '/oembed/' . Strings::base64UrlEncode($src);
-		return '<iframe onload="resizeIframe(this);" class="embed_rich" height="' . $height . '" width="' . $width . '" src="' . $src . '" allowfullscreen scrolling="no" frameborder="no">' . DI::l10n()->t('Embedded content') . '</iframe>';
-	}
-
-	/**
-	 * Generates attribute search XPath string
-	 *
-	 * Generates an XPath query to select elements whose provided attribute contains
-	 * the provided value in a space-separated list.
-	 *
-	 * @param string $attr Name of the attribute to search
-	 * @param string $value Value to search in a space-separated list
-	 * @return string
-	 */
-	private static function buildXPath(string $attr, $value): string
-	{
-		// https://www.westhoffswelt.de/blog/2009/6/9/select-html-elements-with-more-than-one-css-class-using-xpath
-		return "contains(normalize-space(@$attr), ' $value ') or substring(normalize-space(@$attr), 1, string-length('$value') + 1) = '$value ' or substring(normalize-space(@$attr), string-length(@$attr) - string-length('$value')) = ' $value' or @$attr = '$value'";
-	}
-
-	/**
-	 * Returns the inner XML string of a provided DOMNode
-	 *
-	 * @param DOMNode $node
-	 * @return string
-	 */
-	private static function getInnerHTML(DOMNode $node): string
-	{
-		$innerHTML = '';
-		$children = $node->childNodes;
-		foreach ($children as $child) {
-			$innerHTML .= $child->ownerDocument->saveXML($child);
-		}
-		return $innerHTML;
-	}
-
 }
diff --git a/src/Content/Text/BBCode.php b/src/Content/Text/BBCode.php
index f5bba8ce42..3aed82df09 100644
--- a/src/Content/Text/BBCode.php
+++ b/src/Content/Text/BBCode.php
@@ -452,11 +452,7 @@ class BBCode
 
 		$return = '';
 		try {
-			if ($tryoembed && OEmbed::isAllowedURL($data['url'])) {
-				$return = OEmbed::getHTML($data['url'], $data['title']);
-			} else {
-				throw new Exception('OEmbed is disabled for this attachment.');
-			}
+			$return = OEmbed::getHTML($data['url'], $data['title'], $uriid);
 		} catch (Exception $e) {
 			$data['title'] = ($data['title'] ?? '') ?: $data['url'];
 
@@ -1358,12 +1354,12 @@ class BBCode
 				 * $match[1] = $url
 				 * $match[2] = $title or absent
 				 */
-				$try_oembed_callback = function (array $match) {
+				$try_oembed_callback = function (array $match) use ($uriid) {
 					$url = $match[1];
 					$title = $match[2] ?? '';
 
 					try {
-						$return = OEmbed::getHTML($url, $title);
+						$return = OEmbed::getHTML($url, $title, $uriid);
 					} catch (Exception $ex) {
 						$return = $match[0];
 					}
@@ -1381,6 +1377,7 @@ class BBCode
 				$text = preg_replace("#\[(\w*)](\n*)#ism", '$2[$1]', $text);
 				$text = preg_replace("#(\n*)\[/(\w*)]#ism", '[/$2]$1', $text);
 
+				// oembed
 				// Extract the private images which use data urls since preg has issues with
 				// large data sizes. Stash them away while we do bbcode conversion, and then put them back
 				// in after we've done all the regex matching. We cannot use any preg functions to do this.
@@ -1810,7 +1807,7 @@ class BBCode
 				}
 
 				// oembed tag
-				$text = OEmbed::BBCode2HTML($text);
+				$text = OEmbed::BBCode2HTML($text, $uriid);
 
 				// Avoid triple linefeeds through oembed
 				$text = str_replace("<br style='clear:left'></span><br><br>", "<br style='clear:left'></span><br>", $text);
@@ -2058,9 +2055,6 @@ class BBCode
 
 		// Default iframe allowed domains/path
 		$allowedIframeDomains = [
-			DI::baseUrl()->getHost()
-				. (DI::baseUrl()->getPath() ? '/' . DI::baseUrl()->getPath() : '')
-				. '/oembed/', # The path part has to change with the source in Content\Oembed::iframe
 			'www.youtube.com/embed/',
 			'player.vimeo.com/video/',
 		];
diff --git a/src/Model/Post/Media.php b/src/Model/Post/Media.php
index 346a6a1d00..a22b9fba6b 100644
--- a/src/Model/Post/Media.php
+++ b/src/Model/Post/Media.php
@@ -365,7 +365,7 @@ class Media
 	 */
 	private static function addPage(array $media): array
 	{
-		$data = ParseUrl::getSiteinfoCached($media['url'], false);
+		$data = ParseUrl::getSiteinfoCached($media['url']);
 		$media['preview'] = $data['images'][0]['src'] ?? null;
 		$media['preview-height'] = $data['images'][0]['height'] ?? null;
 		$media['preview-width'] = $data['images'][0]['width'] ?? null;
diff --git a/src/Module/Oembed.php b/src/Module/Oembed.php
deleted file mode 100644
index 68e13a2e86..0000000000
--- a/src/Module/Oembed.php
+++ /dev/null
@@ -1,74 +0,0 @@
-<?php
-/**
- * @copyright Copyright (C) 2010-2024, the Friendica project
- *
- * @license GNU AGPL version 3 or any later version
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Affero General Public License as
- * published by the Free Software Foundation, either version 3 of the
- * License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU Affero General Public License for more details.
- *
- * You should have received a copy of the GNU Affero General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- *
- */
-
-namespace Friendica\Module;
-
-use Friendica\BaseModule;
-use Friendica\Content;
-use Friendica\Core\System;
-use Friendica\DI;
-use Friendica\Util\Strings;
-
-/**
- * Oembed module
- *
- * Displays stored embed content based on a base64 hash of a remote URL
- *
- * Example: /oembed/aHR0cHM6Ly9...
- *
- * @author Hypolite Petovan <hypolite@mrpetovan.com>
- */
-class Oembed extends BaseModule
-{
-	protected function content(array $request = []): string
-	{
-		// Unused form: /oembed/b2h?url=...
-		if (DI::args()->getArgv()[1] == 'b2h') {
-			$url = ["", trim(hex2bin($_REQUEST['url']))];
-			echo Content\OEmbed::replaceCallback($url);
-			System::exit();
-		}
-
-		// Unused form: /oembed/h2b?text=...
-		if (DI::args()->getArgv()[1] == 'h2b') {
-			$text = trim(hex2bin($_REQUEST['text']));
-			echo Content\OEmbed::HTML2BBCode($text);
-			System::exit();
-		}
-
-		// @TODO: Replace with parameter from router
-		if (DI::args()->getArgc() == 2) {
-			echo '<html><body>';
-			$url = Strings::base64UrlDecode(DI::args()->getArgv()[1]);
-			$j = Content\OEmbed::fetchURL($url);
-
-			// workaround for media.ccc.de (and any other endpoint that return size 0)
-			if (substr($j->html, 0, 7) == "<iframe" && strstr($j->html, 'width="0"')) {
-				$j->html = '<style>html,body{margin:0;padding:0;} iframe{width:100%;height:100%;}</style>' . $j->html;
-				$j->html = str_replace('width="0"', '', $j->html);
-				$j->html = str_replace('height="0"', '', $j->html);
-			}
-			echo $j->html;
-			echo '</body></html>';
-		}
-		System::exit();
-	}
-}
diff --git a/src/Util/ParseUrl.php b/src/Util/ParseUrl.php
index 1287160576..af05f3b6e9 100644
--- a/src/Util/ParseUrl.php
+++ b/src/Util/ParseUrl.php
@@ -23,7 +23,6 @@ namespace Friendica\Util;
 
 use DOMDocument;
 use DOMXPath;
-use Friendica\Content\OEmbed;
 use Friendica\Content\Text\HTML;
 use Friendica\Protocol\HTTP\MediaType;
 use Friendica\Core\Hook;
@@ -99,8 +98,6 @@ class ParseUrl
 	 * Search for cached embeddable data of an url otherwise fetch it
 	 *
 	 * @param string $url         The url of the page which should be scraped
-	 * @param bool   $do_oembed   The false option is used by the function fetch_oembed()
-	 *                            to avoid endless loops
 	 *
 	 * @return array which contains needed data for embedding
 	 *    string 'url'      => The url of the parsed page
@@ -115,7 +112,7 @@ class ParseUrl
 	 * @see   ParseUrl::getSiteinfo() for more information about scraping
 	 * embeddable content
 	 */
-	public static function getSiteinfoCached(string $url, bool $do_oembed = true): array
+	public static function getSiteinfoCached(string $url): array
 	{
 		if (empty($url)) {
 			return [
@@ -126,15 +123,13 @@ class ParseUrl
 
 		$urlHash = hash('sha256', $url);
 
-		$parsed_url = DBA::selectFirst('parsed_url', ['content'],
-			['url_hash' => $urlHash, 'oembed' => $do_oembed]
-		);
+		$parsed_url = DBA::selectFirst('parsed_url', ['content'], ['url_hash' => $urlHash]);
 		if (!empty($parsed_url['content'])) {
 			$data = unserialize($parsed_url['content']);
 			return $data;
 		}
 
-		$data = self::getSiteinfo($url, $do_oembed);
+		$data = self::getSiteinfo($url);
 
 		$expires = $data['expires'];
 
@@ -144,7 +139,7 @@ class ParseUrl
 			'parsed_url',
 			[
 				'url_hash' => $urlHash,
-				'oembed'   => $do_oembed,
+				'oembed'   => false,
 				'url'      => $url,
 				'content'  => serialize($data),
 				'created'  => DateTimeFormat::utcNow(),
@@ -167,8 +162,6 @@ class ParseUrl
 	 * \<meta name="description" content="An awesome description"\>
 	 *
 	 * @param string $url         The url of the page which should be scraped
-	 * @param bool   $do_oembed   The false option is used by the function fetch_oembed()
-	 *                            to avoid endless loops
 	 * @param int    $count       Internal counter to avoid endless loops
 	 *
 	 * @return array which contains needed data for embedding
@@ -194,7 +187,7 @@ class ParseUrl
 	 * </body>
 	 * @endverbatim
 	 */
-	public static function getSiteinfo(string $url, bool $do_oembed = true, int $count = 1): array
+	public static function getSiteinfo(string $url, int $count = 1): array
 	{
 		if (empty($url)) {
 			return [
@@ -254,41 +247,6 @@ class ParseUrl
 
 		$body = $curlResult->getBodyString();
 
-		if ($do_oembed) {
-			$oembed_data = OEmbed::fetchURL($url, false, false);
-
-			if (!empty($oembed_data->type)) {
-				if (!in_array($oembed_data->type, ['error', 'rich', 'image', 'video', 'audio', ''])) {
-					$siteinfo['type'] = $oembed_data->type;
-				}
-
-				// See https://github.com/friendica/friendica/pull/5763#discussion_r217913178
-				if ($siteinfo['type'] != 'photo') {
-					if (!empty($oembed_data->title)) {
-						$siteinfo['title'] = trim($oembed_data->title);
-					}
-					if (!empty($oembed_data->description)) {
-						$siteinfo['text'] = trim($oembed_data->description);
-					}
-					if (!empty($oembed_data->author_name)) {
-						$siteinfo['author_name'] = trim($oembed_data->author_name);
-					}
-					if (!empty($oembed_data->author_url)) {
-						$siteinfo['author_url'] = Network::sanitizeUrl($oembed_data->author_url);
-					}
-					if (!empty($oembed_data->provider_name)) {
-						$siteinfo['publisher_name'] = trim($oembed_data->provider_name);
-					}
-					if (!empty($oembed_data->provider_url)) {
-						$siteinfo['publisher_url'] = Network::sanitizeUrl($oembed_data->provider_url);
-					}
-					if (!empty($oembed_data->thumbnail_url)) {
-						$siteinfo['image'] = $oembed_data->thumbnail_url;
-					}
-				}
-			}
-		}
-
 		$charset = '';
 		try {
 			// Look for a charset, first in headers
@@ -351,7 +309,7 @@ class ParseUrl
 					}
 				}
 				if ($content != '') {
-					$siteinfo = self::getSiteinfo($content, $do_oembed, ++$count);
+					$siteinfo = self::getSiteinfo($content, ++$count);
 					return $siteinfo;
 				}
 			}
diff --git a/static/defaults.config.php b/static/defaults.config.php
index 7439c7fdf6..8a13c61a39 100644
--- a/static/defaults.config.php
+++ b/static/defaults.config.php
@@ -429,10 +429,6 @@ return [
 		// Don't do count calculations (currently only when showing photo albums).
 		'no_count' => false,
 
-		// no_oembed (Boolean)
-		// Don't use OEmbed to fetch more information about a link.
-		'no_oembed' => false,
-
 		// no_redirect_list (Array)
 		// List of domains where HTTP redirects should be ignored.
 		'no_redirect_list' => [],
diff --git a/static/routes.config.php b/static/routes.config.php
index 67ffec8e2b..fc78f0d6e6 100644
--- a/static/routes.config.php
+++ b/static/routes.config.php
@@ -557,11 +557,6 @@ return [
 
 	'/objects/{guid}[/{activity}]' => [Module\ActivityPub\Objects::class, [R::GET]],
 
-	'/oembed'         => [
-		'/b2h'    => [Module\Oembed::class, [R::GET]],
-		'/h2b'    => [Module\Oembed::class, [R::GET]],
-		'/{hash}' => [Module\Oembed::class, [R::GET]],
-	],
 	'/outbox/{nickname}' => [Module\ActivityPub\Outbox::class, [R::GET, R::POST]],
 	'/owa'               => [Module\Owa::class,                [R::GET]],
 	'/openid'            => [Module\Security\OpenID::class,    [R::GET]],

From 20fd25258a87931799c4f7672396220445390e1b Mon Sep 17 00:00:00 2001
From: Michael <heluecht@pirati.ca>
Date: Sat, 24 Feb 2024 11:35:32 +0000
Subject: [PATCH 2/2] Accidentally changes are reverted

---
 src/Content/OEmbed.php      | 229 ++++++++++++++++++++++++++++++------
 src/Content/Text/BBCode.php |  16 ++-
 src/Model/Post/Media.php    |   2 +-
 src/Module/Oembed.php       |  74 ++++++++++++
 src/Util/ParseUrl.php       |  54 ++++++++-
 static/defaults.config.php  |   4 +
 static/routes.config.php    |   5 +
 7 files changed, 334 insertions(+), 50 deletions(-)
 create mode 100644 src/Module/Oembed.php

diff --git a/src/Content/OEmbed.php b/src/Content/OEmbed.php
index d89cfca3e1..445c52ced0 100644
--- a/src/Content/OEmbed.php
+++ b/src/Content/OEmbed.php
@@ -22,6 +22,8 @@
 namespace Friendica\Content;
 
 use DOMDocument;
+use DOMNode;
+use DOMText;
 use DOMXPath;
 use Exception;
 use Friendica\Core\Cache\Enum\Duration;
@@ -30,10 +32,10 @@ use Friendica\Core\Renderer;
 use Friendica\Database\Database;
 use Friendica\Database\DBA;
 use Friendica\DI;
-use Friendica\Model\Post;
 use Friendica\Network\HTTPClient\Client\HttpClientAccept;
 use Friendica\Util\DateTimeFormat;
 use Friendica\Util\Network;
+use Friendica\Util\ParseUrl;
 use Friendica\Util\Proxy;
 use Friendica\Util\Strings;
 
@@ -47,15 +49,32 @@ use Friendica\Util\Strings;
  */
 class OEmbed
 {
+	/**
+	 * Callback for fetching URL, checking allowance and returning formatted HTML
+	 *
+	 * @param array $matches
+	 * @return string Formatted HTML
+	 */
+	public static function replaceCallback(array $matches): string
+	{
+		$embedurl = $matches[1];
+		$j = self::fetchURL($embedurl, !self::isAllowedURL($embedurl));
+		$s = self::formatObject($j);
+
+		return $s;
+	}
+
 	/**
 	 * Get data from an URL to embed its content.
 	 *
 	 * @param string $embedurl     The URL from which the data should be fetched.
+	 * @param bool   $no_rich_type If set to true rich type content won't be fetched.
+	 * @param bool   $use_parseurl Use the "ParseUrl" functionality to add additional data
 	 *
 	 * @return \Friendica\Object\OEmbed
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	public static function fetchURL(string $embedurl): \Friendica\Object\OEmbed
+	public static function fetchURL(string $embedurl, bool $no_rich_type = false, bool $use_parseurl = true): \Friendica\Object\OEmbed
 	{
 		$embedurl = trim($embedurl, '\'"');
 
@@ -100,7 +119,7 @@ class OEmbed
 							$href = str_replace(['http://www.youtube.com/', 'http://player.vimeo.com/'],
 								['https://www.youtube.com/', 'https://player.vimeo.com/'], $href);
 							$result = DI::httpClient()->fetchFull($href . '&maxwidth=' . $a->getThemeInfoValue('videowidth'));
-							if ($result->isSuccess()) {
+							if ($result->getReturnCode() === 200) {
 								$json_string = $result->getBodyString();
 								break;
 							}
@@ -137,6 +156,60 @@ class OEmbed
 			$oembed->html = str_replace(['http://www.youtube.com/', 'http://player.vimeo.com/'], ['https://www.youtube.com/', 'https://player.vimeo.com/'], $oembed->html);
 		}
 
+		// Improve the OEmbed data with data from OpenGraph, Twitter cards and other sources
+		if ($use_parseurl) {
+			$data = ParseUrl::getSiteinfoCached($embedurl, false);
+
+			if (($oembed->type == 'error') && empty($data['title']) && empty($data['text'])) {
+				return $oembed;
+			}
+
+			if ($no_rich_type || ($oembed->type == 'error')) {
+				$oembed->html = '';
+				$oembed->type = $data['type'];
+
+				if ($oembed->type == 'photo') {
+					if (!empty($data['images'])) {
+						$oembed->url = $data['images'][0]['src'];
+						$oembed->width = $data['images'][0]['width'];
+						$oembed->height = $data['images'][0]['height'];
+					} else {
+						$oembed->type = 'link';
+					}
+				}
+			}
+
+			if (!empty($data['title'])) {
+				$oembed->title = $data['title'];
+			}
+
+			if (!empty($data['text'])) {
+				$oembed->description = $data['text'];
+			}
+
+			if (!empty($data['publisher_name'])) {
+				$oembed->provider_name = $data['publisher_name'];
+			}
+
+			if (!empty($data['publisher_url'])) {
+				$oembed->provider_url = $data['publisher_url'];
+			}
+
+			if (!empty($data['author_name'])) {
+				$oembed->author_name = $data['author_name'];
+			}
+
+			if (!empty($data['author_url'])) {
+				$oembed->author_url = $data['author_url'];
+			}
+
+			if (!empty($data['images']) && ($oembed->type != 'photo')) {
+				$oembed->thumbnail_url = $data['images'][0]['src'];
+				$oembed->thumbnail_width = $data['images'][0]['width'];
+				$oembed->thumbnail_height = $data['images'][0]['height'];
+			}
+		}
+
 		Hook::callAll('oembed_fetch_url', $embedurl, $oembed);
 
 		return $oembed;
@@ -146,20 +219,12 @@ class OEmbed
 	 * Returns a formatted string from OEmbed object
 	 *
 	 * @param \Friendica\Object\OEmbed $oembed
-	 * @param int $uriid
 	 * @return string
 	 */
-	private static function formatObject(\Friendica\Object\OEmbed $oembed, int $uriid): string
+	private static function formatObject(\Friendica\Object\OEmbed $oembed): string
 	{
 		$ret = '<div class="oembed ' . $oembed->type . '">';
 
-		if (!self::isAllowedURL($oembed->url)) {
-			$oembed->html = '';
-			if ($oembed->type == 'rich') {
-				$oembed->type = 'link';
-			}
-		}
-
 		switch ($oembed->type) {
 			case 'video':
 				if ($oembed->thumbnail_url) {
@@ -176,15 +241,15 @@ class OEmbed
 						'$escapedhtml' => base64_encode($oembed->html),
 						'$tw' => $tw,
 						'$th' => $th,
-						'$turl' => Post\Link::getByLink($uriid, $oembed->thumbnail_url, Proxy::SIZE_MEDIUM),
+						'$turl' => $oembed->thumbnail_url,
 					]);
 				} else {
-					$ret .= Proxy::proxifyHtml($oembed->html);
+					$ret = $oembed->html;
 				}
 				break;
 
 			case 'photo':
-				$ret .= '<img width="' . $oembed->width . '" src="' . Post\Link::getByLink($uriid, $oembed->url, Proxy::SIZE_MEDIUM) . '">';
+				$ret .= '<img width="' . $oembed->width . '" src="' . Proxy::proxifyUrl($oembed->url) . '">';
 				break;
 
 			case 'link':
@@ -229,14 +294,6 @@ class OEmbed
 				$ret .= '<a href="' . $oembed->embed_url . '" rel="oembed">' . $oembed->embed_url . '</a>';
 			}
 			$ret .= "</h4>";
-			if ($oembed->type == 'link') {
-				if (!empty($oembed->thumbnail_url)) {
-					$ret .= '<img width="' . $oembed->width . '" src="' . Post\Link::getByLink($uriid, $oembed->thumbnail_url, Proxy::SIZE_MEDIUM) . '">';
-				}
-				if (!empty($oembed->description)) {
-					$ret .= '<p>' . $oembed->description . '</p>';
-				}
-			}
 		} elseif (!strpos($oembed->html, $oembed->embed_url)) {
 			// add <a> for html2bbcode conversion
 			$ret .= '<a href="' . $oembed->embed_url . '" rel="oembed">' . $oembed->title . '</a>';
@@ -251,20 +308,51 @@ class OEmbed
 	 * Converts BBCode to HTML code
 	 *
 	 * @param string $text
-	 * @param int    $uriid
 	 * @return string
 	 */
-	public static function BBCode2HTML(string $text, int $uriid): string
+	public static function BBCode2HTML(string $text): string
 	{
-		if (!preg_match_all("/\[embed\](.+?)\[\/embed\]/is", $text, $matches, PREG_SET_ORDER)) {
+		if (DI::config()->get('system', 'no_oembed')) {
+			return preg_replace("/\[embed\](.+?)\[\/embed\]/is", "<!-- oembed $1 --><i>" . DI::l10n()->t('Embedding disabled') . " : $1</i><!-- /oembed $1 -->", $text);
+		}
+		return preg_replace_callback("/\[embed\](.+?)\[\/embed\]/is", [self::class, 'replaceCallback'], $text);
+	}
+
+	/**
+	 * Find <span class='oembed'>..<a href='url' rel='oembed'>..</a></span>
+	 * and replace it with [embed]url[/embed]
+	 *
+	 * @param string $text
+	 * @return string
+	 */
+	public static function HTML2BBCode(string $text): string
+	{
+		// start parser only if 'oembed' is in text
+		if (strpos($text, 'oembed')) {
+			// convert non ascii chars to html entities
+			$html_text = mb_convert_encoding($text, 'HTML-ENTITIES', mb_detect_encoding($text));
+
+			// If it doesn't parse at all, just return the text.
+			$dom = new DOMDocument();
+			if (!@$dom->loadHTML($html_text)) {
+				return $text;
+			}
+			$xpath = new DOMXPath($dom);
+
+			$xattr = self::buildXPath('class', 'oembed');
+			$entries = $xpath->query("//div[$xattr]");
+
+			$xattr = "@rel='oembed'"; //oe_build_xpath("rel","oembed");
+			foreach ($entries as $e) {
+				$href = $xpath->evaluate("a[$xattr]/@href", $e)->item(0)->nodeValue;
+				if (!is_null($href)) {
+					$e->parentNode->replaceChild(new DOMText('[embed]' . $href . '[/embed]'), $e);
+				}
+			}
+			return self::getInnerHTML($dom->getElementsByTagName('body')->item(0));
+		} else {
 			return $text;
 		}
-
-		foreach ($matches as $match) {
-			$data = self::fetchURL($match[1]);
-			$text = str_replace($match[0], self::formatObject($data, $uriid), $text);
-		}
-		return $text; 
 	}
 
 	/**
@@ -274,7 +362,7 @@ class OEmbed
 	 * @return boolean
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	private static function isAllowedURL(string $url): bool
+	public static function isAllowedURL(string $url): bool
 	{
 		if (!DI::config()->get('system', 'no_oembed_rich_content')) {
 			return true;
@@ -299,13 +387,12 @@ class OEmbed
 	 * Returns a formatted HTML code from given URL and sets optional title
 	 *
 	 * @param string $url URL to fetch
-	 * @param string $title title (default: what comes from OEmbed object)
-	 * @param int    $uriid
+	 * @param string $title Optional title (default: what comes from OEmbed object)
 	 * @return string Formatted HTML
 	 */
-	public static function getHTML(string $url, string $title, int $uriid): string
+	public static function getHTML(string $url, string $title = ''): string
 	{
-		$o = self::fetchURL($url);
+		$o = self::fetchURL($url, !self::isAllowedURL($url));
 
 		if (!is_object($o) || property_exists($o, 'type') && $o->type == 'error') {
 			throw new Exception('OEmbed failed for URL: ' . $url);
@@ -315,8 +402,74 @@ class OEmbed
 			$o->title = $title;
 		}
 
-		$html = self::formatObject($o, $uriid);
+		$html = self::formatObject($o);
 
 		return $html;
 	}
+
+	/**
+	 * Generates the iframe HTML for an oembed attachment.
+	 *
+	 * Width and height are given by the remote, and are regularly too small for
+	 * the generated iframe.
+	 *
+	 * The width is entirely discarded for the actual width of the post, while fixed
+	 * height is used as a starting point before the inevitable resizing.
+	 *
+	 * Since the iframe is automatically resized on load, there are no need for ugly
+	 * and impractical scrollbars.
+	 *
+	 * @todo  This function is currently unused until someone™ adds support for a separate OEmbed domain
+	 *
+	 * @param string $src Original remote URL to embed
+	 * @param string $width
+	 * @param string $height
+	 * @return string Formatted HTML
+	 *
+	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
+	 * @see   oembed_format_object()
+	 */
+	private static function iframe(string $src, string $width, string $height): string
+	{
+		if (!$height || strstr($height, '%')) {
+			$height = '200';
+		}
+		$width = '100%';
+
+		$src = DI::baseUrl() . '/oembed/' . Strings::base64UrlEncode($src);
+		return '<iframe onload="resizeIframe(this);" class="embed_rich" height="' . $height . '" width="' . $width . '" src="' . $src . '" allowfullscreen scrolling="no" frameborder="no">' . DI::l10n()->t('Embedded content') . '</iframe>';
+	}
+
+	/**
+	 * Generates attribute search XPath string
+	 *
+	 * Generates an XPath query to select elements whose provided attribute contains
+	 * the provided value in a space-separated list.
+	 *
+	 * @param string $attr Name of the attribute to search
+	 * @param string $value Value to search in a space-separated list
+	 * @return string
+	 */
+	private static function buildXPath(string $attr, $value): string
+	{
+		// https://www.westhoffswelt.de/blog/2009/6/9/select-html-elements-with-more-than-one-css-class-using-xpath
+		return "contains(normalize-space(@$attr), ' $value ') or substring(normalize-space(@$attr), 1, string-length('$value') + 1) = '$value ' or substring(normalize-space(@$attr), string-length(@$attr) - string-length('$value')) = ' $value' or @$attr = '$value'";
+	}
+
+	/**
+	 * Returns the inner XML string of a provided DOMNode
+	 *
+	 * @param DOMNode $node
+	 * @return string
+	 */
+	private static function getInnerHTML(DOMNode $node): string
+	{
+		$innerHTML = '';
+		$children = $node->childNodes;
+		foreach ($children as $child) {
+			$innerHTML .= $child->ownerDocument->saveXML($child);
+		}
+		return $innerHTML;
+	}
+
 }
diff --git a/src/Content/Text/BBCode.php b/src/Content/Text/BBCode.php
index 3aed82df09..f5bba8ce42 100644
--- a/src/Content/Text/BBCode.php
+++ b/src/Content/Text/BBCode.php
@@ -452,7 +452,11 @@ class BBCode
 
 		$return = '';
 		try {
-			$return = OEmbed::getHTML($data['url'], $data['title'], $uriid);
+			if ($tryoembed && OEmbed::isAllowedURL($data['url'])) {
+				$return = OEmbed::getHTML($data['url'], $data['title']);
+			} else {
+				throw new Exception('OEmbed is disabled for this attachment.');
+			}
 		} catch (Exception $e) {
 			$data['title'] = ($data['title'] ?? '') ?: $data['url'];
 
@@ -1354,12 +1358,12 @@ class BBCode
 				 * $match[1] = $url
 				 * $match[2] = $title or absent
 				 */
-				$try_oembed_callback = function (array $match) use ($uriid) {
+				$try_oembed_callback = function (array $match) {
 					$url = $match[1];
 					$title = $match[2] ?? '';
 
 					try {
-						$return = OEmbed::getHTML($url, $title, $uriid);
+						$return = OEmbed::getHTML($url, $title);
 					} catch (Exception $ex) {
 						$return = $match[0];
 					}
@@ -1377,7 +1381,6 @@ class BBCode
 				$text = preg_replace("#\[(\w*)](\n*)#ism", '$2[$1]', $text);
 				$text = preg_replace("#(\n*)\[/(\w*)]#ism", '[/$2]$1', $text);
 
-				// oembed
 				// Extract the private images which use data urls since preg has issues with
 				// large data sizes. Stash them away while we do bbcode conversion, and then put them back
 				// in after we've done all the regex matching. We cannot use any preg functions to do this.
@@ -1807,7 +1810,7 @@ class BBCode
 				}
 
 				// oembed tag
-				$text = OEmbed::BBCode2HTML($text, $uriid);
+				$text = OEmbed::BBCode2HTML($text);
 
 				// Avoid triple linefeeds through oembed
 				$text = str_replace("<br style='clear:left'></span><br><br>", "<br style='clear:left'></span><br>", $text);
@@ -2055,6 +2058,9 @@ class BBCode
 
 		// Default iframe allowed domains/path
 		$allowedIframeDomains = [
+			DI::baseUrl()->getHost()
+				. (DI::baseUrl()->getPath() ? '/' . DI::baseUrl()->getPath() : '')
+				. '/oembed/', # The path part has to change with the source in Content\Oembed::iframe
 			'www.youtube.com/embed/',
 			'player.vimeo.com/video/',
 		];
diff --git a/src/Model/Post/Media.php b/src/Model/Post/Media.php
index a22b9fba6b..346a6a1d00 100644
--- a/src/Model/Post/Media.php
+++ b/src/Model/Post/Media.php
@@ -365,7 +365,7 @@ class Media
 	 */
 	private static function addPage(array $media): array
 	{
-		$data = ParseUrl::getSiteinfoCached($media['url']);
+		$data = ParseUrl::getSiteinfoCached($media['url'], false);
 		$media['preview'] = $data['images'][0]['src'] ?? null;
 		$media['preview-height'] = $data['images'][0]['height'] ?? null;
 		$media['preview-width'] = $data['images'][0]['width'] ?? null;
diff --git a/src/Module/Oembed.php b/src/Module/Oembed.php
new file mode 100644
index 0000000000..68e13a2e86
--- /dev/null
+++ b/src/Module/Oembed.php
@@ -0,0 +1,74 @@
+<?php
+/**
+ * @copyright Copyright (C) 2010-2024, the Friendica project
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace Friendica\Module;
+
+use Friendica\BaseModule;
+use Friendica\Content;
+use Friendica\Core\System;
+use Friendica\DI;
+use Friendica\Util\Strings;
+
+/**
+ * Oembed module
+ *
+ * Displays stored embed content based on a base64 hash of a remote URL
+ *
+ * Example: /oembed/aHR0cHM6Ly9...
+ *
+ * @author Hypolite Petovan <hypolite@mrpetovan.com>
+ */
+class Oembed extends BaseModule
+{
+	protected function content(array $request = []): string
+	{
+		// Unused form: /oembed/b2h?url=...
+		if (DI::args()->getArgv()[1] == 'b2h') {
+			$url = ["", trim(hex2bin($_REQUEST['url']))];
+			echo Content\OEmbed::replaceCallback($url);
+			System::exit();
+		}
+
+		// Unused form: /oembed/h2b?text=...
+		if (DI::args()->getArgv()[1] == 'h2b') {
+			$text = trim(hex2bin($_REQUEST['text']));
+			echo Content\OEmbed::HTML2BBCode($text);
+			System::exit();
+		}
+
+		// @TODO: Replace with parameter from router
+		if (DI::args()->getArgc() == 2) {
+			echo '<html><body>';
+			$url = Strings::base64UrlDecode(DI::args()->getArgv()[1]);
+			$j = Content\OEmbed::fetchURL($url);
+
+			// workaround for media.ccc.de (and any other endpoint that return size 0)
+			if (substr($j->html, 0, 7) == "<iframe" && strstr($j->html, 'width="0"')) {
+				$j->html = '<style>html,body{margin:0;padding:0;} iframe{width:100%;height:100%;}</style>' . $j->html;
+				$j->html = str_replace('width="0"', '', $j->html);
+				$j->html = str_replace('height="0"', '', $j->html);
+			}
+			echo $j->html;
+			echo '</body></html>';
+		}
+		System::exit();
+	}
+}
diff --git a/src/Util/ParseUrl.php b/src/Util/ParseUrl.php
index af05f3b6e9..1287160576 100644
--- a/src/Util/ParseUrl.php
+++ b/src/Util/ParseUrl.php
@@ -23,6 +23,7 @@ namespace Friendica\Util;
 
 use DOMDocument;
 use DOMXPath;
+use Friendica\Content\OEmbed;
 use Friendica\Content\Text\HTML;
 use Friendica\Protocol\HTTP\MediaType;
 use Friendica\Core\Hook;
@@ -98,6 +99,8 @@ class ParseUrl
 	 * Search for cached embeddable data of an url otherwise fetch it
 	 *
 	 * @param string $url         The url of the page which should be scraped
+	 * @param bool   $do_oembed   The false option is used by the function fetch_oembed()
+	 *                            to avoid endless loops
 	 *
 	 * @return array which contains needed data for embedding
 	 *    string 'url'      => The url of the parsed page
@@ -112,7 +115,7 @@ class ParseUrl
 	 * @see   ParseUrl::getSiteinfo() for more information about scraping
 	 * embeddable content
 	 */
-	public static function getSiteinfoCached(string $url): array
+	public static function getSiteinfoCached(string $url, bool $do_oembed = true): array
 	{
 		if (empty($url)) {
 			return [
@@ -123,13 +126,15 @@ class ParseUrl
 
 		$urlHash = hash('sha256', $url);
 
-		$parsed_url = DBA::selectFirst('parsed_url', ['content'], ['url_hash' => $urlHash]);
+		$parsed_url = DBA::selectFirst('parsed_url', ['content'],
+			['url_hash' => $urlHash, 'oembed' => $do_oembed]
+		);
 		if (!empty($parsed_url['content'])) {
 			$data = unserialize($parsed_url['content']);
 			return $data;
 		}
 
-		$data = self::getSiteinfo($url);
+		$data = self::getSiteinfo($url, $do_oembed);
 
 		$expires = $data['expires'];
 
@@ -139,7 +144,7 @@ class ParseUrl
 			'parsed_url',
 			[
 				'url_hash' => $urlHash,
-				'oembed'   => false,
+				'oembed'   => $do_oembed,
 				'url'      => $url,
 				'content'  => serialize($data),
 				'created'  => DateTimeFormat::utcNow(),
@@ -162,6 +167,8 @@ class ParseUrl
 	 * \<meta name="description" content="An awesome description"\>
 	 *
 	 * @param string $url         The url of the page which should be scraped
+	 * @param bool   $do_oembed   The false option is used by the function fetch_oembed()
+	 *                            to avoid endless loops
 	 * @param int    $count       Internal counter to avoid endless loops
 	 *
 	 * @return array which contains needed data for embedding
@@ -187,7 +194,7 @@ class ParseUrl
 	 * </body>
 	 * @endverbatim
 	 */
-	public static function getSiteinfo(string $url, int $count = 1): array
+	public static function getSiteinfo(string $url, bool $do_oembed = true, int $count = 1): array
 	{
 		if (empty($url)) {
 			return [
@@ -247,6 +254,41 @@ class ParseUrl
 
 		$body = $curlResult->getBodyString();
 
+		if ($do_oembed) {
+			$oembed_data = OEmbed::fetchURL($url, false, false);
+
+			if (!empty($oembed_data->type)) {
+				if (!in_array($oembed_data->type, ['error', 'rich', 'image', 'video', 'audio', ''])) {
+					$siteinfo['type'] = $oembed_data->type;
+				}
+
+				// See https://github.com/friendica/friendica/pull/5763#discussion_r217913178
+				if ($siteinfo['type'] != 'photo') {
+					if (!empty($oembed_data->title)) {
+						$siteinfo['title'] = trim($oembed_data->title);
+					}
+					if (!empty($oembed_data->description)) {
+						$siteinfo['text'] = trim($oembed_data->description);
+					}
+					if (!empty($oembed_data->author_name)) {
+						$siteinfo['author_name'] = trim($oembed_data->author_name);
+					}
+					if (!empty($oembed_data->author_url)) {
+						$siteinfo['author_url'] = Network::sanitizeUrl($oembed_data->author_url);
+					}
+					if (!empty($oembed_data->provider_name)) {
+						$siteinfo['publisher_name'] = trim($oembed_data->provider_name);
+					}
+					if (!empty($oembed_data->provider_url)) {
+						$siteinfo['publisher_url'] = Network::sanitizeUrl($oembed_data->provider_url);
+					}
+					if (!empty($oembed_data->thumbnail_url)) {
+						$siteinfo['image'] = $oembed_data->thumbnail_url;
+					}
+				}
+			}
+		}
+
 		$charset = '';
 		try {
 			// Look for a charset, first in headers
@@ -309,7 +351,7 @@ class ParseUrl
 					}
 				}
 				if ($content != '') {
-					$siteinfo = self::getSiteinfo($content, ++$count);
+					$siteinfo = self::getSiteinfo($content, $do_oembed, ++$count);
 					return $siteinfo;
 				}
 			}
diff --git a/static/defaults.config.php b/static/defaults.config.php
index 8a13c61a39..7439c7fdf6 100644
--- a/static/defaults.config.php
+++ b/static/defaults.config.php
@@ -429,6 +429,10 @@ return [
 		// Don't do count calculations (currently only when showing photo albums).
 		'no_count' => false,
 
+		// no_oembed (Boolean)
+		// Don't use OEmbed to fetch more information about a link.
+		'no_oembed' => false,
+
 		// no_redirect_list (Array)
 		// List of domains where HTTP redirects should be ignored.
 		'no_redirect_list' => [],
diff --git a/static/routes.config.php b/static/routes.config.php
index 77d04f92c1..146255adc6 100644
--- a/static/routes.config.php
+++ b/static/routes.config.php
@@ -557,6 +557,11 @@ return [
 
 	'/objects/{guid}[/{activity}]' => [Module\ActivityPub\Objects::class, [R::GET]],
 
+	'/oembed'         => [
+		'/b2h'    => [Module\Oembed::class, [R::GET]],
+		'/h2b'    => [Module\Oembed::class, [R::GET]],
+		'/{hash}' => [Module\Oembed::class, [R::GET]],
+	],
 	'/outbox/{nickname}' => [Module\ActivityPub\Outbox::class, [R::GET, R::POST]],
 	'/owa'               => [Module\Owa::class,                [R::GET]],
 	'/openid'            => [Module\Security\OpenID::class,    [R::GET]],