chore: Move to Typescript (#2783)

This PR moves the entire project to Typescript. Due to the ~1000 ignores this will lead to a messy codebase for a while, but the churn is worth it – all of those ignore comments are places that were never type-safe previously.

closes #1282

app/components/Authenticated.tsx

@@ -0,0 +1,58 @@
+import { observer } from "mobx-react";
+import * as React from "react";
+import { useTranslation } from "react-i18next";
+import { Redirect } from "react-router-dom";
+import { isCustomSubdomain } from "@shared/utils/domains";
+import LoadingIndicator from "~/components/LoadingIndicator";
+import env from "~/env";
+import useStores from "~/hooks/useStores";
+import { changeLanguage } from "~/utils/language";
+
+type Props = {
+  children: JSX.Element;
+};
+
+const Authenticated = ({ children }: Props) => {
+  const { auth } = useStores();
+  const { i18n } = useTranslation();
+  const language = auth.user && auth.user.language;
+
+  // Watching for language changes here as this is the earliest point we have
+  // the user available and means we can start loading translations faster
+  React.useEffect(() => {
+    changeLanguage(language, i18n);
+  }, [i18n, language]);
+
+  if (auth.authenticated) {
+    const { user, team } = auth;
+    const { hostname } = window.location;
+
+    if (!team || !user) {
+      return <LoadingIndicator />;
+    }
+
+    // If we're authenticated but viewing a domain that doesn't match the
+    // current team then kick the user to the teams correct domain.
+    if (team.domain) {
+      if (team.domain !== hostname) {
+        window.location.href = `${team.url}${window.location.pathname}`;
+        return <LoadingIndicator />;
+      }
+    } else if (
+      env.SUBDOMAINS_ENABLED &&
+      team.subdomain &&
+      isCustomSubdomain(hostname) &&
+      !hostname.startsWith(`${team.subdomain}.`)
+    ) {
+      window.location.href = `${team.url}${window.location.pathname}`;
+      return <LoadingIndicator />;
+    }
+
+    return children;
+  }
+
+  auth.logout(true);
+  return <Redirect to="/" />;
+};
+
+export default observer(Authenticated);