New group call experience: Call tiles (#9332)

* Add call tiles

* Factor CallDuration out into a reusable component

* Correct the separator character in LiveContentSummary

src/components/views/voip/CallDuration.tsx

@@ -0,0 +1,51 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+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 React, { FC, useState, useEffect } from "react";
+
+import type { MatrixEvent } from "matrix-js-sdk/src/models/event";
+import { formatCallTime } from "../../../DateUtils";
+
+interface CallDurationProps {
+    delta: number;
+}
+
+/**
+ * A call duration counter.
+ */
+export const CallDuration: FC<CallDurationProps> = ({ delta }) => {
+    // Clock desync could lead to a negative duration, so just hide it if that happens
+    if (delta <= 0) return null;
+    return <div className="mx_CallDuration">{ formatCallTime(new Date(delta)) }</div>;
+};
+
+interface CallDurationFromEventProps {
+    mxEvent: MatrixEvent;
+}
+
+/**
+ * A call duration counter that automatically counts up, given the event that
+ * started the call.
+ */
+export const CallDurationFromEvent: FC<CallDurationFromEventProps> = ({ mxEvent }) => {
+    const [now, setNow] = useState(() => Date.now());
+    useEffect(() => {
+        const timer = setInterval(() => setNow(Date.now()), 1000);
+        return () => clearInterval(timer);
+    }, []);
+
+    return <CallDuration delta={now - mxEvent.getTs()} />;
+};