Live location sharing - basic maximised beacon map (#8310)

* open a dialog with map centered around first beacon

Signed-off-by: Kerry Archibald <kerrya@element.io>

* add room member markers

Signed-off-by: Kerry Archibald <kerrya@element.io>

* fix unmount issue in smart marker

Signed-off-by: Kerry Archibald <kerrya@element.io>

* dont throw on no more live locations

Signed-off-by: Kerry Archibald <kerrya@element.io>

* cursor on beacon maps

Signed-off-by: Kerry Archibald <kerrya@element.io>

* fussy import ordering

Signed-off-by: Kerry Archibald <kerrya@element.io>

* test dialog opening from beacon body

Signed-off-by: Kerry Archibald <kerrya@element.io>

* test beaconmarker

Signed-off-by: Kerry Archibald <kerrya@element.io>

* test BeaconViewDialog

Signed-off-by: Kerry Archibald <kerrya@element.io>

* comment

Signed-off-by: Kerry Archibald <kerrya@element.io>

* use unstable prefix for wk tile_Server

Signed-off-by: Kerry Archibald <kerrya@element.io>

* unstable prefix for new m.tile_server use in test

Signed-off-by: Kerry Archibald <kerrya@element.io>

src/utils/beacon/useLiveBeacons.ts

@@ -0,0 +1,41 @@
+/*
+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 {
+    Beacon,
+    Room,
+    RoomStateEvent,
+    MatrixClient,
+} from "matrix-js-sdk/src/matrix";
+
+import { useEventEmitterState } from "../../hooks/useEventEmitter";
+
+/**
+ * Returns an array of all live beacon ids for a given room
+ *
+ * Beacons are removed from array when they become inactive
+ */
+export const useLiveBeacons = (roomId: Room['roomId'], matrixClient: MatrixClient): Beacon[] => {
+    const room = matrixClient.getRoom(roomId);
+
+    const liveBeacons = useEventEmitterState(
+        room.currentState,
+        RoomStateEvent.BeaconLiveness,
+        () => room.currentState?.liveBeaconIds.map(beaconIdentifier => room.currentState.beacons.get(beaconIdentifier)),
+    );
+
+    return liveBeacons;
+};