1 files changed, 37 insertions, 0 deletions
diff --git a/apps/files/src/services/PreviewService.ts b/apps/files/src/services/PreviewService.ts
new file mode 100644
index 00000000000..840d6a48afa
--- /dev/null
+++ b/apps/files/src/services/PreviewService.ts
@@ -0,0 +1,37 @@
+/**
+ * @copyright Copyright (c) 2023 John Molakvoæ <skjnldsv@protonmail.com>
+ *
+ * @author John Molakvoæ <skjnldsv@protonmail.com>
+ *
+ * @license AGPL-3.0-or-later
+ *
+ * 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/>.
+ *
+ */
+
+// The preview service worker cache name (see webpack config)
+const SWCacheName = 'previews'
+
+/**
+ * Check if the preview is already cached by the service worker
+ */
+export const isCachedPreview = function(previewUrl: string) {
+	return caches.open(SWCacheName)
+		.then(function(cache) {
+			return cache.match(previewUrl)
+				.then(function(response) {
+					return !!response
+				})
+		})
+}