From f344ed376cb35b25309db9cb58b01feb6b4592b0 Mon Sep 17 00:00:00 2001
From: Hugo Sales <hugo@hsal.es>
Date: Wed, 15 Sep 2021 16:49:29 +0100
Subject: [PATCH] [ATTACHMENTS][Embed][UI] Allow plugins to provide a title for
 an attachment, if a note has none, implement such a mechanism in Embed and
 cache the result, since it is potentially costly

---
 plugins/Embed/Embed.php   | 11 +++++++++++
 src/Entity/Attachment.php | 26 ++++++++++++++++++++------
 2 files changed, 31 insertions(+), 6 deletions(-)

diff --git a/plugins/Embed/Embed.php b/plugins/Embed/Embed.php
index 53da857889..42a42f78fa 100644
--- a/plugins/Embed/Embed.php
+++ b/plugins/Embed/Embed.php
@@ -485,6 +485,17 @@ class Embed extends Plugin
         return HTTPClient::get($url)->getContent();
     }
 
+    public function onAttachmentGetBestTitle(Attachment $attachment, Note $note, ?string &$title)
+    {
+        try {
+            $embed = DB::findOneBy('attachment_embed', ['attachment_id' => $attachment->getId()]);
+            $title = $embed->getTitle();
+            return Event::stop;
+        } catch (NotFoundException) {
+        }
+        return Event::next;
+    }
+
     /**
      * Event raised when GNU social polls the plugin for information about it.
      * Adds this plugin's version information to $versions array
diff --git a/src/Entity/Attachment.php b/src/Entity/Attachment.php
index 1c00445d30..5e9aed84db 100644
--- a/src/Entity/Attachment.php
+++ b/src/Entity/Attachment.php
@@ -21,8 +21,10 @@
 
 namespace App\Entity;
 
+use App\Core\Cache;
 use App\Core\DB\DB;
 use App\Core\Entity;
+use App\Core\Event;
 use App\Core\GSFile;
 use function App\Core\I18n\_m;
 use App\Core\Log;
@@ -294,12 +296,24 @@ class Attachment extends Entity
     {
         // If we have a note, then the best title is the title itself
         if (!is_null(($note))) {
-            $attachment_to_note = DB::findOneBy('attachment_to_note', [
-                'attachment_id' => $this->getId(),
-                'note_id'       => $note->getId(),
-            ]);
-            if (!is_null($attachment_to_note->getTitle())) {
-                return $attachment_to_note->getTitle();
+            $title = Cache::get('attachment-title-' . $this->getId() . '-' . $note->getId(), function () use ($note) {
+                try {
+                    $attachment_to_note = DB::findOneBy('attachment_to_note', [
+                        'attachment_id' => $this->getId(),
+                        'note_id'       => $note->getId(),
+                    ]);
+                    if (!is_null($attachment_to_note->getTitle())) {
+                        return $attachment_to_note->getTitle();
+                    }
+                } catch (NotFoundException) {
+                    $title = null;
+                    Event::handle('AttachmentGetBestTitle', [$this, $note, &$title]);
+                    return $title;
+                }
+                return null;
+            });
+            if ($title != null) {
+                return $title;
             }
         }
         // Else