Implement MSC2965 action parameter (#1673)

* redirect session_end action to session detail

* fix react key warning in oauth session detail

* move Route type to /routing

* test getRouteActionRedirection

* comment

* frontend: Split the routing-related stuff in multiple files under routing/

* frontend: Cover all the redirections defined by MSC2965

* frontend: fix test

* Make the backend keep query parameters through login to the /account/ interface

* Fix frontend tests & clippy lints

---------

Co-authored-by: Quentin Gliech <quenting@element.io>

frontend/src/routing/atoms.ts

@@ -0,0 +1,48 @@
+// Copyright 2023 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 { atom } from "jotai";
+import { atomWithLocation } from "jotai-location";
+
+import { Location, pathToRoute, Route, routeToPath } from "./routes";
+
+export const appConfigAtom = atom<AppConfig>(
+  typeof window !== "undefined" ? window.APP_CONFIG : { root: "/" },
+);
+
+const locationToRoute = (root: string, location: Location): Route => {
+  if (!location.pathname || !location.pathname.startsWith(root)) {
+    throw new Error(`Invalid location ${location.pathname}`);
+  }
+
+  const path = location.pathname.slice(root.length);
+  return pathToRoute(path);
+};
+
+export const locationAtom = atomWithLocation();
+
+export const routeAtom = atom(
+  (get) => {
+    const location = get(locationAtom);
+    const config = get(appConfigAtom);
+    return locationToRoute(config.root, location);
+  },
+  (get, set, value: Route, searchParams?: URLSearchParams) => {
+    const appConfig = get(appConfigAtom);
+    set(locationAtom, {
+      pathname: appConfig.root + routeToPath(value),
+      searchParams,
+    });
+  },
+);