Redux state: Allow multiple calls to be stored

ts/state/selectors/calling.ts

@@ -0,0 +1,33 @@
+// Copyright 2020 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import { createSelector } from 'reselect';
+
+import { CallingStateType } from '../ducks/calling';
+import { CallState } from '../../types/Calling';
+import { getOwn } from '../../util/getOwn';
+
+const getActiveCallState = (state: CallingStateType) => state.activeCallState;
+
+const getCallsByConversation = (state: CallingStateType) =>
+  state.callsByConversation;
+
+// In theory, there could be multiple incoming calls. In practice, neither RingRTC nor the
+//   UI are ready to handle this.
+export const getIncomingCall = createSelector(
+  getCallsByConversation,
+  callsByConversation =>
+    Object.values(callsByConversation).find(
+      call => call.isIncoming && call.callState === CallState.Ringing
+    )
+);
+
+export const getActiveCall = createSelector(
+  getActiveCallState,
+  getCallsByConversation,
+  (activeCallState, callsByConversation) =>
+    activeCallState &&
+    getOwn(callsByConversation, activeCallState.conversationId)
+);
+
+export const isCallActive = createSelector(getActiveCall, Boolean);