diff --git a/vector/src/main/java/im/vector/app/features/media/VectorAttachmentViewerActivity.kt b/vector/src/main/java/im/vector/app/features/media/VectorAttachmentViewerActivity.kt
index 3dae1f5ed2..2c51bf0947 100644
--- a/vector/src/main/java/im/vector/app/features/media/VectorAttachmentViewerActivity.kt
+++ b/vector/src/main/java/im/vector/app/features/media/VectorAttachmentViewerActivity.kt
@@ -273,7 +273,6 @@ class VectorAttachmentViewerActivity : AttachmentViewerActivity(), AttachmentInt
     //  check if it is already possible to save from menu with long press on video
     override fun onDownload() {
         // TODO
-        //  create interface for base use case
         //  create ViewModel with action downloadAction, events downloading, downloaded, error
         //  call usecase using viewModel
         //  launch coroutine in Activity using repeatOnLifeCycle extension
diff --git a/vector/src/main/java/im/vector/app/features/media/domain/usecase/DownloadMediaUseCase.kt b/vector/src/main/java/im/vector/app/features/media/domain/usecase/DownloadMediaUseCase.kt
index e7b7d02f01..f493058281 100644
--- a/vector/src/main/java/im/vector/app/features/media/domain/usecase/DownloadMediaUseCase.kt
+++ b/vector/src/main/java/im/vector/app/features/media/domain/usecase/DownloadMediaUseCase.kt
@@ -30,20 +30,20 @@ import javax.inject.Inject
 class DownloadMediaUseCase @Inject constructor(
         @ApplicationContext private val appContext: Context,
         private val notificationUtils: NotificationUtils
-) {
+) : VectorInOutUseCase<File, Unit> {
 
     /* ==========================================================================================
      * Public API
      * ========================================================================================== */
 
     // TODO find a way to provide Dispatchers via Interface to be able to unit tests
-    suspend fun execute(file: File): Result<Unit> = withContext(Dispatchers.IO) {
+    override suspend fun execute(input: File): Result<Unit> = withContext(Dispatchers.IO) {
         runCatching {
             saveMedia(
                     context = appContext,
-                    file = file,
-                    title = file.name,
-                    mediaMimeType = getMimeTypeFromUri(appContext, file.toUri()),
+                    file = input,
+                    title = input.name,
+                    mediaMimeType = getMimeTypeFromUri(appContext, input.toUri()),
                     notificationUtils = notificationUtils
             )
         }
diff --git a/vector/src/main/java/im/vector/app/features/media/domain/usecase/VectorInOutUseCase.kt b/vector/src/main/java/im/vector/app/features/media/domain/usecase/VectorInOutUseCase.kt
new file mode 100644
index 0000000000..d7c7585250
--- /dev/null
+++ b/vector/src/main/java/im/vector/app/features/media/domain/usecase/VectorInOutUseCase.kt
@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) 2022 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package im.vector.app.features.media.domain.usecase
+
+// TODO move into Core packages
+interface VectorInOutUseCase<T, R> {
+    suspend fun execute(input: T): Result<R>
+}