]> git.mxchange.org Git - friendica.git/blobdiff - src/Model/Post/Media.php
Avoid local network communication / invalid url requests
[friendica.git] / src / Model / Post / Media.php
index 89b5d37704dfa0926a0c32bd61046ca739623902..8216d7383719e314dd7a87e5c390bbf2182f5f6c 100644 (file)
@@ -1,6 +1,6 @@
 <?php
 /**
- * @copyright Copyright (C) 2010-2021, the Friendica project
+ * @copyright Copyright (C) 2010-2023, the Friendica project
  *
  * @license GNU AGPL version 3 or any later version
  *
 
 namespace Friendica\Model\Post;
 
-use Friendica\Content\PageInfo;
 use Friendica\Content\Text\BBCode;
 use Friendica\Core\Logger;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\Database;
 use Friendica\Database\DBA;
 use Friendica\DI;
+use Friendica\Model\Contact;
 use Friendica\Model\Item;
+use Friendica\Model\ItemURI;
+use Friendica\Model\Photo;
 use Friendica\Model\Post;
+use Friendica\Network\HTTPClient\Client\HttpClientAccept;
+use Friendica\Network\HTTPClient\Client\HttpClientOptions;
 use Friendica\Util\Images;
+use Friendica\Util\Network;
 use Friendica\Util\ParseUrl;
+use Friendica\Util\Proxy;
 use Friendica\Util\Strings;
 
 /**
@@ -52,12 +59,15 @@ class Media
        const HTML        = 17;
        const XML         = 18;
        const PLAIN       = 19;
+       const ACTIVITY    = 20;
+       const ACCOUNT     = 21;
        const DOCUMENT    = 128;
 
        /**
         * Insert a post-media record
         *
         * @param array $media
+        * @param bool  $force
         * @return void
         */
        public static function insert(array $media, bool $force = false)
@@ -67,6 +77,11 @@ class Media
                        return;
                }
 
+               if (DBA::exists('post-media', ['uri-id' => $media['uri-id'], 'preview' => $media['url']])) {
+                       Logger::info('Media already exists as preview', ['uri-id' => $media['uri-id'], 'url' => $media['url'], 'callstack' => System::callstack()]);
+                       return;
+               }
+
                // "document" has got the lowest priority. So when the same file is both attached as document
                // and embedded as picture then we only store the picture or replace the document
                $found = DBA::selectFirst('post-media', ['type'], ['uri-id' => $media['uri-id'], 'url' => $media['url']]);
@@ -75,7 +90,13 @@ class Media
                        return;
                }
 
+               if (!ItemURI::exists($media['uri-id'])) {
+                       Logger::info('Media referenced URI ID not found', ['uri-id' => $media['uri-id'], 'url' => $media['url'], 'callstack' => System::callstack()]);
+                       return;
+               }
+
                $media = self::unsetEmptyFields($media);
+               $media = DI::dbaDefinition()->truncateFieldsForTable('post-media', $media);
 
                // We are storing as fast as possible to avoid duplicated network requests
                // when fetching additional information for pictures and other content.
@@ -85,6 +106,7 @@ class Media
 
                $media = self::fetchAdditionalData($media);
                $media = self::unsetEmptyFields($media);
+               $media = DI::dbaDefinition()->truncateFieldsForTable('post-media', $media);
 
                if (array_diff_assoc($media, $stored)) {
                        $result = DBA::insert('post-media', $media, Database::INSERT_UPDATE);
@@ -100,9 +122,9 @@ class Media
         * @param array $media
         * @return array cleaned media array
         */
-       private static function unsetEmptyFields(array $media)
+       private static function unsetEmptyFields(array $media): array
        {
-               $fields = ['mimetype', 'height', 'width', 'size', 'preview', 'preview-height', 'preview-width', 'description'];
+               $fields = ['mimetype', 'height', 'width', 'size', 'preview', 'preview-height', 'preview-width', 'blurhash', 'description'];
                foreach ($fields as $field) {
                        if (empty($media[$field])) {
                                unset($media[$field]);
@@ -136,7 +158,7 @@ class Media
         * @param string $title
         * @return string "[attach]" element
         */
-       public static function getAttachElement(string $href, int $length, string $type, string $title = '')
+       public static function getAttachElement(string $href, int $length, string $type, string $title = ''): string
        {
                $media = self::fetchAdditionalData(['type' => self::DOCUMENT, 'url' => $href,
                        'size' => $length, 'mimetype' => $type, 'description' => $title]);
@@ -151,18 +173,28 @@ class Media
         * @param array $media
         * @return array media array with additional data
         */
-       public static function fetchAdditionalData(array $media)
+       public static function fetchAdditionalData(array $media): array
        {
+               if (Network::isLocalLink($media['url'])) {
+                       $media = self::fetchLocalData($media);
+               }
+
                // Fetch the mimetype or size if missing.
-               if (empty($media['mimetype']) || empty($media['size'])) {
+               if (Network::isValidHttpUrl($media['url']) && (empty($media['mimetype']) || empty($media['size']))) {
                        $timeout = DI::config()->get('system', 'xrd_timeout');
-                       $curlResult = DI::httpRequest()->head($media['url'], ['timeout' => $timeout]);
+                       $curlResult = DI::httpClient()->head($media['url'], [HttpClientOptions::TIMEOUT => $timeout]);
+
+                       // Workaround for systems that can't handle a HEAD request
+                       if (!$curlResult->isSuccess() && ($curlResult->getReturnCode() == 405)) {
+                               $curlResult = DI::httpClient()->get($media['url'], HttpClientAccept::DEFAULT, [HttpClientOptions::TIMEOUT => $timeout]);
+                       }
+
                        if ($curlResult->isSuccess()) {
                                if (empty($media['mimetype'])) {
-                                       $media['mimetype'] = $curlResult->getHeader('Content-Type');
+                                       $media['mimetype'] = $curlResult->getHeader('Content-Type')[0] ?? '';
                                }
                                if (empty($media['size'])) {
-                                       $media['size'] = (int)$curlResult->getHeader('Content-Length');
+                                       $media['size'] = (int)($curlResult->getHeader('Content-Length')[0] ?? 0);
                                }
                        } else {
                                Logger::notice('Could not fetch head', ['media' => $media]);
@@ -173,17 +205,18 @@ class Media
 
                if (($media['type'] == self::IMAGE) || ($filetype == 'image')) {
                        $imagedata = Images::getInfoFromURLCached($media['url']);
-                       if (!empty($imagedata)) {
+                       if ($imagedata) {
                                $media['mimetype'] = $imagedata['mime'];
                                $media['size'] = $imagedata['size'];
                                $media['width'] = $imagedata[0];
                                $media['height'] = $imagedata[1];
+                               $media['blurhash'] = $imagedata['blurhash'] ?? null;
                        } else {
                                Logger::notice('No image data', ['media' => $media]);
                        }
                        if (!empty($media['preview'])) {
                                $imagedata = Images::getInfoFromURLCached($media['preview']);
-                               if (!empty($imagedata)) {
+                               if ($imagedata) {
                                        $media['preview-width'] = $imagedata[0];
                                        $media['preview-height'] = $imagedata[1];
                                }
@@ -194,20 +227,173 @@ class Media
                        $media = self::addType($media);
                }
 
+               if (in_array($media['type'], [self::TEXT, self::APPLICATION, self::HTML, self::XML, self::PLAIN])) {
+                       $media = self::addActivity($media);
+               }
+
+               if (in_array($media['type'], [self::TEXT, self::APPLICATION, self::HTML, self::XML, self::PLAIN])) {
+                       $media = self::addAccount($media);
+               }
+
                if ($media['type'] == self::HTML) {
-                       $data = ParseUrl::getSiteinfoCached($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;
-                       $media['description'] = $data['text'] ?? null;
-                       $media['name'] = $data['title'] ?? null;
-                       $media['author-url'] = $data['author_url'] ?? null;
-                       $media['author-name'] = $data['author_name'] ?? null;
-                       $media['author-image'] = $data['author_img'] ?? null;
-                       $media['publisher-url'] = $data['publisher_url'] ?? null;
-                       $media['publisher-name'] = $data['publisher_name'] ?? null;
-                       $media['publisher-image'] = $data['publisher_img'] ?? null;
+                       $media = self::addPage($media);
+               }
+
+               return $media;
+       }
+
+       /**
+        * Adds the activity type if the media entry is linked to an activity
+        *
+        * @param array $media
+        * @return array
+        */
+       private static function addActivity(array $media): array
+       {
+               $id = Item::fetchByLink($media['url']);
+               if (empty($id)) {
+                       return $media;
+               }
+
+               $item = Post::selectFirst([], ['id' => $id, 'network' => Protocol::FEDERATED]);
+               if (empty($item['id'])) {
+                       Logger::debug('Not a federated activity', ['id' => $id, 'uri-id' => $media['uri-id'], 'url' => $media['url']]);
+                       return $media;
+               }
+
+               if (!empty($item['plink']) && Strings::compareLink($item['plink'], $media['url']) &&
+                       parse_url($item['plink'], PHP_URL_HOST) != parse_url($item['uri'], PHP_URL_HOST)) {
+                       Logger::debug('Not a link to an activity', ['uri-id' => $media['uri-id'], 'url' => $media['url'], 'plink' => $item['plink'], 'uri' => $item['uri']]);
+                       return $media;
+               }
+
+               if (in_array($item['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN])) {
+                       $media['mimetype'] = 'application/activity+json';
+               } elseif ($item['network'] == Protocol::DIASPORA) {
+                       $media['mimetype'] = 'application/xml';
+               }
+
+               $contact = Contact::getById($item['author-id'], ['avatar', 'gsid']);
+               if (!empty($contact['gsid'])) {
+                       $gserver = DBA::selectFirst('gserver', ['url', 'site_name'], ['id' => $contact['gsid']]);
+               }
+
+               $media['type'] = self::ACTIVITY;
+               $media['media-uri-id'] = $item['uri-id'];
+               $media['height'] = null;
+               $media['width'] = null;
+               $media['preview'] = null;
+               $media['preview-height'] = null;
+               $media['preview-width'] = null;
+               $media['blurhash'] = null;
+               $media['description'] = $item['body'];
+               $media['name'] = $item['title'];
+               $media['author-url'] = $item['author-link'];
+               $media['author-name'] = $item['author-name'];
+               $media['author-image'] = $contact['avatar'] ?? $item['author-avatar'];
+               $media['publisher-url'] = $gserver['url'] ?? null;
+               $media['publisher-name'] = $gserver['site_name'] ?? null;
+               $media['publisher-image'] = null;
+
+               Logger::debug('Activity detected', ['uri-id' => $media['uri-id'], 'url' => $media['url'], 'plink' => $item['plink'], 'uri' => $item['uri']]);
+               return $media;
+       }
+
+       /**
+        * Adds the account type if the media entry is linked to an account
+        *
+        * @param array $media
+        * @return array
+        */
+       private static function addAccount(array $media): array
+       {
+               $contact = Contact::getByURL($media['url'], false);
+               if (empty($contact) || ($contact['network'] == Protocol::PHANTOM)) {
+                       return $media;
+               }
+
+               if (in_array($contact['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN])) {
+                       $media['mimetype'] = 'application/activity+json';
+               }
+
+               if (!empty($contact['gsid'])) {
+                       $gserver = DBA::selectFirst('gserver', ['url', 'site_name'], ['id' => $contact['gsid']]);
                }
+
+               $media['type'] = self::ACCOUNT;
+               $media['media-uri-id'] = $contact['uri-id'];
+               $media['height'] = null;
+               $media['width'] = null;
+               $media['preview'] = null;
+               $media['preview-height'] = null;
+               $media['preview-width'] = null;
+               $media['blurhash'] = null;
+               $media['description'] = $contact['about'];
+               $media['name'] = $contact['name'];
+               $media['author-url'] = $contact['url'];
+               $media['author-name'] = $contact['name'];
+               $media['author-image'] = $contact['avatar'];
+               $media['publisher-url'] = $gserver['url'] ?? null;
+               $media['publisher-name'] = $gserver['site_name'] ?? null;
+               $media['publisher-image'] = null;
+
+               Logger::debug('Account detected', ['uri-id' => $media['uri-id'], 'url' => $media['url'], 'uri' => $contact['url']]);
+               return $media;
+       }
+
+       /**
+        * Add page infos for HTML entries
+        *
+        * @param array $media
+        * @return array
+        */
+       private static function addPage(array $media): array
+       {
+               $data = ParseUrl::getSiteinfoCached($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;
+               $media['blurhash'] = $data['images'][0]['blurhash'] ?? null;
+               $media['description'] = $data['text'] ?? null;
+               $media['name'] = $data['title'] ?? null;
+               $media['author-url'] = $data['author_url'] ?? null;
+               $media['author-name'] = $data['author_name'] ?? null;
+               $media['author-image'] = $data['author_img'] ?? null;
+               $media['publisher-url'] = $data['publisher_url'] ?? null;
+               $media['publisher-name'] = $data['publisher_name'] ?? null;
+               $media['publisher-image'] = $data['publisher_img'] ?? null;
+
+               return $media;
+       }
+
+       /**
+        * Fetch media data from local resources
+        * @param array $media
+        * @return array media with added data
+        */
+       private static function fetchLocalData(array $media): array
+       {
+               if (!preg_match('|.*?/photo/(.*[a-fA-F0-9])\-(.*[0-9])\..*[\w]|', $media['url'] ?? '', $matches)) {
+                       return $media;
+               }
+               $photo = Photo::selectFirst([], ['resource-id' => $matches[1], 'scale' => $matches[2]]);
+               if (!empty($photo)) {
+                       $media['mimetype'] = $photo['type'];
+                       $media['size'] = $photo['datasize'];
+                       $media['width'] = $photo['width'];
+                       $media['height'] = $photo['height'];
+                       $media['blurhash'] = $photo['blurhash'];
+               }
+
+               if (!preg_match('|.*?/photo/(.*[a-fA-F0-9])\-(.*[0-9])\..*[\w]|', $media['preview'] ?? '', $matches)) {
+                       return $media;
+               }
+               $photo = Photo::selectFirst([], ['resource-id' => $matches[1], 'scale' => $matches[2]]);
+               if (!empty($photo)) {
+                       $media['preview-width'] = $photo['width'];
+                       $media['preview-height'] = $photo['height'];
+               }
+
                return $media;
        }
 
@@ -217,7 +403,7 @@ class Media
         * @param array $data
         * @return array data array with the detected type
         */
-       public static function addType(array $data)
+       public static function addType(array $data): array
        {
                if (empty($data['mimetype'])) {
                        Logger::info('No MimeType provided', ['media' => $data]);
@@ -269,7 +455,7 @@ class Media
         * @param string $preview Preview picture
         * @return boolean
         */
-       private static function isPictureLink(string $page, string $preview)
+       private static function isPictureLink(string $page, string $preview): bool
        {
                return preg_match('#/photos/.*/image/#ism', $page) && preg_match('#/photo/.*-1\.#ism', $preview);
        }
@@ -281,13 +467,14 @@ class Media
         * @param string $body
         * @return string Body without media links
         */
-       public static function insertFromBody(int $uriid, string $body)
+       public static function insertFromBody(int $uriid, string $body, bool $endmatch = false): string
        {
+               $endmatchpattern = $endmatch ? '\z' : '';
                // Simplify image codes
-               $body = preg_replace("/\[img\=([0-9]*)x([0-9]*)\](.*?)\[\/img\]/ism", '[img]$3[/img]', $body);
+               $unshared_body = $body = preg_replace("/\[img\=([0-9]*)x([0-9]*)\](.*?)\[\/img\]$endmatchpattern/ism", '[img]$3[/img]', $body);
 
                $attachments = [];
-               if (preg_match_all("#\[url=([^\]]+?)\]\s*\[img=([^\[\]]*)\]([^\[\]]*)\[\/img\]\s*\[/url\]#ism", $body, $pictures, PREG_SET_ORDER)) {
+               if (preg_match_all("#\[url=([^\]]+?)\]\s*\[img=([^\[\]]*)\]([^\[\]]*)\[\/img\]\s*\[/url\]$endmatchpattern#ism", $body, $pictures, PREG_SET_ORDER)) {
                        foreach ($pictures as $picture) {
                                if (!self::isPictureLink($picture[1], $picture[2])) {
                                        continue;
@@ -299,14 +486,14 @@ class Media
                        }
                }
 
-               if (preg_match_all("/\[img=([^\[\]]*)\]([^\[\]]*)\[\/img\]/Usi", $body, $pictures, PREG_SET_ORDER)) {
+               if (preg_match_all("/\[img=([^\[\]]*)\]([^\[\]]*)\[\/img\]$endmatchpattern/Usi", $body, $pictures, PREG_SET_ORDER)) {
                        foreach ($pictures as $picture) {
                                $body = str_replace($picture[0], '', $body);
                                $attachments[$picture[1]] = ['uri-id' => $uriid, 'type' => self::IMAGE, 'url' => $picture[1], 'description' => $picture[2]];
                        }
                }
 
-               if (preg_match_all("#\[url=([^\]]+?)\]\s*\[img\]([^\[]+?)\[/img\]\s*\[/url\]#ism", $body, $pictures, PREG_SET_ORDER)) {
+               if (preg_match_all("#\[url=([^\]]+?)\]\s*\[img\]([^\[]+?)\[/img\]\s*\[/url\]$endmatchpattern#ism", $body, $pictures, PREG_SET_ORDER)) {
                        foreach ($pictures as $picture) {
                                if (!self::isPictureLink($picture[1], $picture[2])) {
                                        continue;
@@ -318,45 +505,116 @@ class Media
                        }
                }
 
-               if (preg_match_all("/\[img\]([^\[\]]*)\[\/img\]/ism", $body, $pictures, PREG_SET_ORDER)) {
+               if (preg_match_all("/\[img\]([^\[\]]*)\[\/img\]$endmatchpattern/ism", $body, $pictures, PREG_SET_ORDER)) {
                        foreach ($pictures as $picture) {
                                $body = str_replace($picture[0], '', $body);
                                $attachments[$picture[1]] = ['uri-id' => $uriid, 'type' => self::IMAGE, 'url' => $picture[1]];
                        }
                }
 
-               if (preg_match_all("/\[audio\]([^\[\]]*)\[\/audio\]/ism", $body, $audios, PREG_SET_ORDER)) {
+               if (preg_match_all("/\[audio\]([^\[\]]*)\[\/audio\]$endmatchpattern/ism", $body, $audios, PREG_SET_ORDER)) {
                        foreach ($audios as $audio) {
                                $body = str_replace($audio[0], '', $body);
                                $attachments[$audio[1]] = ['uri-id' => $uriid, 'type' => self::AUDIO, 'url' => $audio[1]];
                        }
                }
 
-               if (preg_match_all("/\[video\]([^\[\]]*)\[\/video\]/ism", $body, $videos, PREG_SET_ORDER)) {
+               if (preg_match_all("/\[video\]([^\[\]]*)\[\/video\]$endmatchpattern/ism", $body, $videos, PREG_SET_ORDER)) {
                        foreach ($videos as $video) {
                                $body = str_replace($video[0], '', $body);
                                $attachments[$video[1]] = ['uri-id' => $uriid, 'type' => self::VIDEO, 'url' => $video[1]];
                        }
                }
 
-               $url = PageInfo::getRelevantUrlFromBody($body);
-               if (!empty($url)) {
-                       Logger::debug('Got page url', ['url' => $url]);
-                       $attachments[$url] = ['uri-id' => $uriid, 'type' => self::UNKNOWN, 'url' => $url];
-               }
+               if ($uriid != 0) {
+                       foreach ($attachments as $attachment) {
+                               if (Post\Link::exists($uriid, $attachment['preview'] ?? $attachment['url'])) {
+                                       continue;
+                               }
 
-               foreach ($attachments as $attachment) {
-                       self::insert($attachment);
+                               // Only store attachments that are part of the unshared body
+                               if (Item::containsLink($unshared_body, $attachment['preview'] ?? $attachment['url'], $attachment['type'])) {
+                                       self::insert($attachment);
+                               }
+                       }
                }
 
                return trim($body);
        }
 
+       /**
+        * Remove media that is at the end of the body
+        *
+        * @param string $body
+        * @return string
+        */
+       public static function removeFromEndOfBody(string $body): string
+       {
+               do {
+                       $prebody = $body;
+                       $body = self::insertFromBody(0, $body, true);
+               } while ($prebody != $body);
+               return $body;
+       }
+
+       /**
+        * Add media links from a relevant url in the body
+        *
+        * @param integer $uriid
+        * @param string $body
+        * @return void
+        */
+       public static function insertFromRelevantUrl(int $uriid, string $body, string $fullbody, string $network)
+       {
+               // Remove all hashtags and mentions
+               $body = preg_replace("/([#@!])\[url\=(.*?)\](.*?)\[\/url\]/ism", '', $body);
+
+               // Search for pure links
+               if (preg_match_all("/\[url\](https?:.*?)\[\/url\]/ism", $body, $matches)) {
+                       foreach ($matches[1] as $url) {
+                               Logger::info('Got page url (link without description)', ['uri-id' => $uriid, 'url' => $url]);
+                               self::insert(['uri-id' => $uriid, 'type' => self::UNKNOWN, 'url' => $url], false, $network);
+                               if ($network == Protocol::DFRN) {
+                                       self::revertHTMLType($uriid, $url, $fullbody);
+                               }
+                       }
+               }
+
+               // Search for links with descriptions
+               if (preg_match_all("/\[url\=(https?:.*?)\].*?\[\/url\]/ism", $body, $matches)) {
+                       foreach ($matches[1] as $url) {
+                               Logger::info('Got page url (link with description)', ['uri-id' => $uriid, 'url' => $url]);
+                               self::insert(['uri-id' => $uriid, 'type' => self::UNKNOWN, 'url' => $url], false, $network);
+                               if ($network == Protocol::DFRN) {
+                                       self::revertHTMLType($uriid, $url, $fullbody);
+                               }
+                       }
+               }
+       }
+
+       /**
+        * Revert the media type of links to UNKNOWN for DFRN posts when they aren't attached
+        *
+        * @param integer $uriid
+        * @param string $url
+        * @param string $body
+        * @return void
+        */
+       private static function revertHTMLType(int $uriid, string $url, string $body)
+       {
+               $attachment = BBCode::getAttachmentData($body);
+               if (!empty($attachment['url']) && Network::getUrlMatch($attachment['url'], $url)) {
+                       return;
+               }
+               DBA::update('post-media', ['type' => self::UNKNOWN], ['uri-id' => $uriid, 'type' => self::HTML, 'url' => $url]);
+       }
+
        /**
         * Add media links from the attachment field
         *
         * @param integer $uriid
         * @param string $body
+        * @return void
         */
        public static function insertFromAttachmentData(int $uriid, string $body)
        {
@@ -412,33 +670,33 @@ class Media
        /**
         * Retrieves the media attachments associated with the provided item ID.
         *
-        * @param int $uri_id
-        * @param array $types
-        * @return array
+        * @param int $uri_id URI id
+        * @param array $types Media types
+        * @return array|bool Array on success, false on error
         * @throws \Exception
         */
        public static function getByURIId(int $uri_id, array $types = [])
        {
-               $condition = ['uri-id' => $uri_id];
+               $condition = ["`uri-id` = ? AND `type` != ?", $uri_id, self::UNKNOWN];
 
                if (!empty($types)) {
                        $condition = DBA::mergeConditions($condition, ['type' => $types]);
                }
 
-               return DBA::selectToArray('post-media', [], $condition);
+               return DBA::selectToArray('post-media', [], $condition, ['order' => ['id']]);
        }
 
        /**
         * Checks if media attachments are associated with the provided item ID.
         *
-        * @param int $uri_id
-        * @param array $types
-        * @return array
+        * @param int $uri_id URI id
+        * @param array $types Media types
+        * @return bool Whether media attachment exists
         * @throws \Exception
         */
-       public static function existsByURIId(int $uri_id, array $types = [])
+       public static function existsByURIId(int $uri_id, array $types = []): bool
        {
-               $condition = ['uri-id' => $uri_id];
+               $condition = ["`uri-id` = ? AND `type` != ?", $uri_id, self::UNKNOWN];
 
                if (!empty($types)) {
                        $condition = DBA::mergeConditions($condition, ['type' => $types]);
@@ -449,23 +707,28 @@ class Media
 
        /**
         * Split the attachment media in the three segments "visual", "link" and "additional"
-        * 
-        * @param int    $uri_id 
-        * @param string $guid
-        * @param array  $links ist of links that shouldn't be added 
+        *
+        * @param int    $uri_id URI id
+        * @param array  $links list of links that shouldn't be added
+        * @param bool   $has_media
         * @return array attachments
         */
-       public static function splitAttachments(int $uri_id, string $guid = '', array $links = [])
+       public static function splitAttachments(int $uri_id, array $links = [], bool $has_media = true): array
        {
                $attachments = ['visual' => [], 'link' => [], 'additional' => []];
 
+               if (!$has_media) {
+                       return $attachments;
+               }
+
                $media = self::getByURIId($uri_id);
                if (empty($media)) {
                        return $attachments;
                }
 
-               $height = 0;
+               $heights = [];
                $selected = '';
+               $previews = [];
 
                foreach ($media as $medium) {
                        foreach ($links as $link) {
@@ -474,7 +737,24 @@ class Media
                                }
                        }
 
-                       $type = explode('/', current(explode(';', $medium['mimetype'])));
+                       // Avoid adding separate media entries for previews
+                       foreach ($previews as $preview) {
+                               if (Strings::compareLink($preview, $medium['url'])) {
+                                       continue 2;
+                               }
+                       }
+
+                       // Currently these two types are ignored here.
+                       // Posts are added differently and contacts are not displayed as attachments.
+                       if (in_array($medium['type'], [self::ACCOUNT, self::ACTIVITY])) {
+                               continue;
+                       }
+
+                       if (!empty($medium['preview'])) {
+                               $previews[] = $medium['preview'];
+                       }
+
+                       $type = explode('/', explode(';', $medium['mimetype'] ?? '')[0]);
                        if (count($type) < 2) {
                                Logger::info('Unknown MimeType', ['type' => $type, 'media' => $medium]);
                                $filetype = 'unkn';
@@ -496,14 +776,11 @@ class Media
                                in_array($filetype, ['audio', 'image'])) {
                                $attachments['visual'][] = $medium;
                        } elseif (($medium['type'] == self::VIDEO) || ($filetype == 'video')) {
-                               if (strpos($medium['url'], $guid) !== false) {
+                               if (!empty($medium['height'])) {
                                        // Peertube videos are delivered in many different resolutions. We pick a moderate one.
-                                       // By checking against the GUID we also ensure to only work this way on Peertube posts.
-                                       // This wouldn't be executed when someone for example on Mastodon was sharing multiple videos in a single post.
-                                       if (empty($height) || ($height > $medium['height']) && ($medium['height'] >= 480)) {
-                                               $height = $medium['height'];
-                                               $selected = $medium['url'];
-                                       }
+                                       // Since only Peertube provides a "height" parameter, this wouldn't be executed
+                                       // when someone for example on Mastodon was sharing multiple videos in a single post.
+                                       $heights[$medium['height']] = $medium['url'];
                                        $video[$medium['url']] = $medium;
                                } else {
                                        $attachments['visual'][] = $medium;
@@ -512,24 +789,37 @@ class Media
                                $attachments['additional'][] = $medium;
                        }
                }
-               if (!empty($selected)) {
-                       $attachments['visual'][] = $video[$selected];
-                       unset($video[$selected]);
-                       foreach ($video as $element) {
-                               $attachments['additional'][] = $element;
+
+               if (!empty($heights)) {
+                       ksort($heights);
+                       foreach ($heights as $height => $url) {
+                               if (empty($selected) || $height <= 480) {
+                                       $selected = $url;
+                               }
+                       }
+
+                       if (!empty($selected)) {
+                               $attachments['visual'][] = $video[$selected];
+                               unset($video[$selected]);
+                               foreach ($video as $element) {
+                                       $attachments['additional'][] = $element;
+                               }
                        }
                }
+
                return $attachments;
        }
 
        /**
         * Add media attachments to the body
         *
-        * @param int $uriid
+        * @param int    $uriid
         * @param string $body
+        * @param array  $types
+        *
         * @return string body
         */
-       public static function addAttachmentsToBody(int $uriid, string $body = '')
+       public static function addAttachmentsToBody(int $uriid, string $body = '', array $types = [self::IMAGE, self::AUDIO, self::VIDEO]): string
        {
                if (empty($body)) {
                        $item = Post::selectFirst(['body'], ['uri-id' => $uriid]);
@@ -538,18 +828,28 @@ class Media
                        }
                        $body = $item['body'];
                }
+               $original_body = $body;
+
                $body = preg_replace("/\s*\[attachment .*?\].*?\[\/attachment\]\s*/ism", '', $body);
 
-               foreach (self::getByURIId($uriid, [self::IMAGE, self::AUDIO, self::VIDEO]) as $media) {
-                       if (Item::containsLink($body, $media['url'])) {
+               foreach (self::getByURIId($uriid, $types) as $media) {
+                       if (Item::containsLink($body, $media['preview'] ?? $media['url'], $media['type'])) {
                                continue;
                        }
 
                        if ($media['type'] == self::IMAGE) {
-                               if (!empty($media['description'])) {
-                                       $body .= "\n[img=" . $media['url'] . ']' . $media['description'] .'[/img]';
+                               if (!empty($media['preview'])) {
+                                       if (!empty($media['description'])) {
+                                               $body .= "\n[url=" . $media['url'] . "][img=" . $media['preview'] . ']' . $media['description'] .'[/img][/url]';
+                                       } else {
+                                               $body .= "\n[url=" . $media['url'] . "][img]" . $media['preview'] .'[/img][/url]';
+                                       }
                                } else {
-                                       $body .= "\n[img]" . $media['url'] .'[/img]';
+                                       if (!empty($media['description'])) {
+                                               $body .= "\n[img=" . $media['url'] . ']' . $media['description'] .'[/img]';
+                                       } else {
+                                               $body .= "\n[img]" . $media['url'] .'[/img]';
+                                       }
                                }
                        } elseif ($media['type'] == self::AUDIO) {
                                $body .= "\n[audio]" . $media['url'] . "[/audio]\n";
@@ -558,10 +858,70 @@ class Media
                        }
                }
 
-               if (preg_match("/.*(\[attachment.*?\].*?\[\/attachment\]).*/ism", $item['body'], $match)) {
+               if (preg_match("/.*(\[attachment.*?\].*?\[\/attachment\]).*/ism", $original_body, $match)) {
                        $body .= "\n" . $match[1];
                }
 
                return $body;
        }
+
+       /**
+        * Get preview link for given media id
+        *
+        * @param integer $id   media id
+        * @param string  $size One of the Proxy::SIZE_* constants
+        * @return string preview link
+        */
+       public static function getPreviewUrlForId(int $id, string $size = ''): string
+       {
+               $url = DI::baseUrl() . '/photo/preview/';
+               switch ($size) {
+                       case Proxy::SIZE_MICRO:
+                               $url .= Proxy::PIXEL_MICRO . '/';
+                               break;
+                       case Proxy::SIZE_THUMB:
+                               $url .= Proxy::PIXEL_THUMB . '/';
+                               break;
+                       case Proxy::SIZE_SMALL:
+                               $url .= Proxy::PIXEL_SMALL . '/';
+                               break;
+                       case Proxy::SIZE_MEDIUM:
+                               $url .= Proxy::PIXEL_MEDIUM . '/';
+                               break;
+                       case Proxy::SIZE_LARGE:
+                               $url .= Proxy::PIXEL_LARGE . '/';
+                               break;
+               }
+               return $url . $id;
+       }
+
+       /**
+        * Get media link for given media id
+        *
+        * @param integer $id   media id
+        * @param string  $size One of the Proxy::SIZE_* constants
+        * @return string media link
+        */
+       public static function getUrlForId(int $id, string $size = ''): string
+       {
+               $url = DI::baseUrl() . '/photo/media/';
+               switch ($size) {
+                       case Proxy::SIZE_MICRO:
+                               $url .= Proxy::PIXEL_MICRO . '/';
+                               break;
+                       case Proxy::SIZE_THUMB:
+                               $url .= Proxy::PIXEL_THUMB . '/';
+                               break;
+                       case Proxy::SIZE_SMALL:
+                               $url .= Proxy::PIXEL_SMALL . '/';
+                               break;
+                       case Proxy::SIZE_MEDIUM:
+                               $url .= Proxy::PIXEL_MEDIUM . '/';
+                               break;
+                       case Proxy::SIZE_LARGE:
+                               $url .= Proxy::PIXEL_LARGE . '/';
+                               break;
+               }
+               return $url . $id;
+       }
 }