[ATTACHMENTS] Even more further refactoring

Introduce Encoder plugins Instead of abstract upload and thumb modules

Ported attachment routes. In v3 thumbnail depends on existing attachment
so route updated accordingly.

plugins/ImageEncoder/Controller/ImageThumbnail.php

@@ -0,0 +1,62 @@
+<?php
+
+// {{{ License
+
+// This file is part of GNU social - https://www.gnu.org/software/social
+//
+// GNU social 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.
+//
+// GNU social 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 GNU social.  If not, see <http://www.gnu.org/licenses/>.
+
+// }}}
+
+namespace Plugin\ImageEncoder\Controller;
+
+use App\Core\Controller;
+use App\Core\DB\DB;
+use App\Core\GSFile;
+use App\Entity\AttachmentThumbnail;
+use App\Util\Common;
+use Symfony\Component\HttpFoundation\Request;
+
+class ImageThumbnail extends Controller
+{
+    /**
+     * Get a thumbnail for the attachment with id $id
+     */
+    public function thumbnail(Request $request, int $id)
+    {
+        $attachment = DB::findOneBy('attachment', ['id' => $id]);
+        if (!is_null($attachment->getScope())) {
+            // && ($attachment->scope | VisibilityScope::PUBLIC) != 0
+            // $user = Common::ensureLoggedIn();
+            assert(false, 'Attachment scope not implemented');
+        }
+
+        // TODO rate limit
+
+        $max_width  = Common::config('thumbnail', 'width');
+        $max_height = Common::config('thumbnail', 'height');
+        $width      = Common::clamp($this->int('w') ?? $max_width,  min: 0, max: $max_width);
+        $height     = Common::clamp($this->int('h') ?? $max_height, min: 0, max: $max_height);
+        $crop       = $this->bool('c') ?? false;
+
+        $thumbnail = AttachmentThumbnail::getOrCreate(attachment: $attachment, width: $width, height: $height, crop: $crop);
+        DB::persist($thumbnail);
+        DB::flush();
+
+        $filename = $thumbnail->getFilename();
+        $path     = $thumbnail->getPath();
+
+        return GSFile::sendFile(filepath: $path, mimetype: $attachment->getMimetype(), output_filename: $filename, disposition: 'inline');
+    }
+}