feat: add preview provider for emf files based on office

Signed-off-by: Daniel Kesselberg <[email protected]>

Author: kesselb

config/config.sample.php

@@ -1285,6 +1285,7 @@
  *  - ``OC\Preview\StarOffice``
  *  - ``OC\Preview\SVG``
  *  - ``OC\Preview\TIFF``
+ *  - ``OC\Preview\EMF``
  *
  *
  * Defaults to the following providers:
@@ -1945,7 +1946,7 @@
  *
  * Example for windows systems: ``array('?', '<', '>', ':', '*', '|', '"', chr(0), "\n", "\r")``
  * see https://en.wikipedia.org/wiki/Comparison_of_file_systems#Limits
- * 
+ *
  * Defaults to ``array()``
  */
 'forbidden_chars' => [],

core/js/mimetypelist.js

@@ -113,7 +113,8 @@ OC.MimeTypeList={
     "application/vnd.xmind.workbook": "mindmap",
     "image/targa": "image/tga",
     "application/vnd.openxmlformats-officedocument.wordprocessingml.document.oform": "x-office/form",
-    "application/vnd.openxmlformats-officedocument.wordprocessingml.document.docxf": "x-office/form-template"
+    "application/vnd.openxmlformats-officedocument.wordprocessingml.document.docxf": "x-office/form-template",
+    "image/x-emf": "image/emf"
 },
 	files: [
     "application",

lib/private/Preview/EMF.php

@@ -0,0 +1,35 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright 2023 Daniel Kesselberg <[email protected]>
+ *
+ * @author Daniel Kesselberg <[email protected]>
+ *
+ * @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 <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OC\Preview;
+
+class EMF extends Office
+{
+	public function getMimeType(): string
+	{
+		return '/image\/emf/';
+	}
+}

lib/private/PreviewManager.php

@@ -408,6 +408,7 @@ protected function registerCoreProviders() {
 					$this->registerCoreProvider(Preview\MSOffice2007::class, '/application\/vnd.openxmlformats-officedocument.*/', ["officeBinary" => $officeBinary]);
 					$this->registerCoreProvider(Preview\OpenDocument::class, '/application\/vnd.oasis.opendocument.*/', ["officeBinary" => $officeBinary]);
 					$this->registerCoreProvider(Preview\StarOffice::class, '/application\/vnd.sun.xml.*/', ["officeBinary" => $officeBinary]);
+					$this->registerCoreProvider(Preview\EMF::class, '/image\/emf/', ['officeBinary' => $officeBinary]);
 				}
 			}
 		}

resources/config/mimetypealiases.dist.json

@@ -114,5 +114,6 @@
 	"application/vnd.xmind.workbook": "mindmap",
 	"image/targa": "image/tga",
 	"application/vnd.openxmlformats-officedocument.wordprocessingml.document.oform": "x-office/form",
-	"application/vnd.openxmlformats-officedocument.wordprocessingml.document.docxf": "x-office/form-template"
+	"application/vnd.openxmlformats-officedocument.wordprocessingml.document.docxf": "x-office/form-template",
+	"image/x-emf": "image/emf"
 }

resources/config/mimetypemapping.dist.json

@@ -51,6 +51,7 @@
 	"dot": ["application/msword"],
 	"dotx": ["application/vnd.openxmlformats-officedocument.wordprocessingml.template"],
 	"dv": ["video/dv"],
+	"emf": ["image/emf"],
 	"eot": ["application/vnd.ms-fontobject"],
 	"eps": ["application/postscript"],
 	"epub": ["application/epub+zip"],