Split MediaViewModel into multiple files

src/state/media/MediaViewModel.ts

@@ -0,0 +1,44 @@
+/*
+Copyright 2023, 2024 New Vector Ltd.
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE in the repository root for full details.
+*/
+
+import { type Behavior } from "../Behavior";
+import { type ScreenShareViewModel } from "./ScreenShareViewModel";
+import { type UserMediaViewModel } from "./UserMediaViewModel";
+
+/**
+ * A participant's media.
+ */
+export type MediaViewModel = UserMediaViewModel | ScreenShareViewModel;
+
+/**
+ * Properties which are common to all MediaViewModels.
+ */
+export interface BaseMediaViewModel {
+  /**
+   * An opaque identifier for this media.
+   */
+  id: string;
+  /**
+   * The Matrix user to which this media belongs.
+   */
+  userId: string;
+  displayName$: Behavior<string>;
+  mxcAvatarUrl$: Behavior<string | undefined>;
+}
+
+export type BaseMediaInputs = BaseMediaViewModel;
+
+// All this function does is strip out superfluous data from the input object
+export function createBaseMedia({
+  id,
+  userId,
+  displayName$,
+  mxcAvatarUrl$,
+}: BaseMediaInputs): BaseMediaViewModel {
+  return { id, userId, displayName$, mxcAvatarUrl$ };
+}