some cleanup

src/domain/BrawlViewModel.js

@@ -39,6 +39,7 @@ export class BrawlViewModel extends ViewModel {
     }
 
     async load() {
+        // TODO: deduplicate code here
         this.track(this.navigation.observe("login").subscribe(shown => {
             if (shown) {
                 this._showLogin();
@@ -125,7 +126,7 @@ export class BrawlViewModel extends ViewModel {
                     sessionContainer.startWithExistingSession(sessionId);
                     return sessionContainer;
                 },
-                sessionCallback: sessionContainer => this._sessionCallback(sessionContainer)
+                sessionCallback: this._sessionCallback
             });
             this._sessionLoadViewModel.start();
         });

src/domain/navigation/URLRouter.js

@@ -23,7 +23,7 @@ export class URLRouter {
         this._navigation = navigation;
     }
 
-    start() {
+    attach() {
         this._subscription = this._history.subscribe(url => {
             this._applyUrl(url);
         });
@@ -60,6 +60,7 @@ export class URLRouter {
     }
 
     replaceUrl(url) {
+        // TODO: we don't want this to always to trigger an update
         this._history.replaceUrl(url);
     }
 

src/domain/navigation/index.js

@@ -0,0 +1,32 @@
+/*
+Copyright 2020 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 {Navigation} from "./Navigation.js";
+
+export function createNavigation() {
+    return new Navigation(function allowsChild(parent, child) {
+        const {type} = child;
+        switch (parent?.type) {
+            case undefined:
+                // allowed root segments
+                return type === "login"  || type === "session";
+            case "session":
+                return type === "room" || type === "rooms" || type === "settings";
+            default:
+                return false;
+        }
+    });
+}

src/main.js

@@ -22,7 +22,7 @@ import {SessionContainer} from "./matrix/SessionContainer.js";
 import {StorageFactory} from "./matrix/storage/idb/StorageFactory.js";
 import {SessionInfoStorage} from "./matrix/sessioninfo/localstorage/SessionInfoStorage.js";
 import {BrawlViewModel} from "./domain/BrawlViewModel.js";
-import {Navigation} from "./domain/navigation/Navigation.js";
+import {createNavigation} from "./domain/navigation/index.js";
 import {URLRouter} from "./domain/navigation/URLRouter.js";
 import {BrawlView} from "./ui/web/BrawlView.js";
 import {Clock} from "./ui/web/dom/Clock.js";
@@ -118,20 +118,9 @@ export async function main(container, paths, legacyExtras) {
             workerPromise = loadOlmWorker(paths);
         }
 
-        const navigation = new Navigation(function allowsChild(parent, child) {
-            const {type} = child;
-            switch (parent?.type) {
-                case undefined:
-                    // allowed root segments
-                    return type === "login"  || type === "session";
-                case "session":
-                    return type === "room" || type === "settings";
-                default:
-                    return false;
-            }
-        });
+        const navigation = createNavigation();
         const urlRouter = new URLRouter(new History(), navigation);
-        urlRouter.start();
+        urlRouter.attach();
 
         const vm = new BrawlViewModel({
             createSessionContainer: () => {