Stop devices from automatically sleeping

A TypeScript upgrade was necessary to bring in the types for the wake lock API.

src/room/InCallView.tsx

@@ -83,6 +83,7 @@ import { useFullscreen } from "./useFullscreen";
 import { useLayoutStates } from "../video-grid/Layout";
 import { useSFUConfig } from "../livekit/OpenIDLoader";
 import { E2EELock } from "../E2EELock";
+import { useWakeLock } from "../useWakeLock";
 
 const canScreenshare = "getDisplayMedia" in (navigator.mediaDevices ?? {});
 // There is currently a bug in Safari our our code with cloning and sending MediaStreams
@@ -132,6 +133,7 @@ export function InCallView({
 }: InCallViewProps) {
   const { t } = useTranslation();
   usePreventScroll();
+  useWakeLock();
 
   const containerRef1 = useRef<HTMLDivElement | null>(null);
   const [containerRef2, bounds] = useMeasure({ polyfill: ResizeObserver });

src/useWakeLock.ts

@@ -0,0 +1,56 @@
+/*
+Copyright 2023 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.
+*/
+
+import { logger } from "matrix-js-sdk/src/logger";
+import { useEffect } from "react";
+
+/**
+ * React hook that inhibits the device from automatically going to sleep.
+ */
+export const useWakeLock = () => {
+  useEffect(() => {
+    if ("wakeLock" in navigator) {
+      let mounted = true;
+      let lock: WakeLockSentinel | null = null;
+
+      const onVisiblityChange = async () => {
+        if (document.visibilityState === "visible") {
+          try {
+            lock = await navigator.wakeLock.request("screen");
+            if (!mounted)
+              lock
+                .release()
+                .catch((e) => logger.warn("Can't release wake lock", e));
+          } catch (e) {
+            logger.warn("Can't acquire wake lock", e);
+          }
+        }
+      };
+
+      onVisiblityChange();
+      document.addEventListener("visiblitychange", onVisiblityChange);
+
+      return () => {
+        mounted = false;
+        if (lock !== null)
+          lock
+            .release()
+            .catch((e) => logger.warn("Can't release wake lock", e));
+        document.removeEventListener("visiblitychange", onVisiblityChange);
+      };
+    }
+  }, []);
+};