assets/tailwind.config.js

@@ -12,7 +12,6 @@ module.exports = {
     "../lib/mv_web.ex",
     "../lib/mv_web/**/*.*ex"
   ],
-  safelist: ['h-screen', 'px-6', 'h-screen', 'place-items-center', 'px-20', 'px-24'], // Classes that are used by AshAuthentication Sign-In Page are otherwise purged
   theme: {
     extend: {
       colors: {

lib/mv_web/auth_overrides.ex

@@ -17,7 +17,7 @@ defmodule MvWeb.AuthOverrides do
 
   # Avoid full-width for the Sign In Form
   override AshAuthentication.Phoenix.Components.SignIn do
-    set :root_class, "min-w-md"
+    set :root_class, "md:min-w-md"
   end
 
   # Replace banner logo with text

lib/mv_web/live_user_auth.ex

@@ -36,9 +36,11 @@ defmodule MvWeb.LiveUserAuth do
     end
   end
 
-  def on_mount(:live_no_user, _params, _session, socket) do
-    Gettext.put_locale(MvWeb.Gettext, "de")
-    {:cont, assign(socket, :locale, "de")}
+  def on_mount(:live_no_user, _params, session, socket) do
+    # Set the locale for not logged in user to set the language
+    locale = session["locale"] || "en"
+    Gettext.put_locale(MvWeb.Gettext, locale)
+    {:cont, assign(socket, :locale, locale)}
 
     if socket.assigns[:current_user] do
       {:halt, Phoenix.LiveView.redirect(socket, to: ~p"/")}

lib/mv_web/router.ex

@@ -139,8 +139,47 @@ defmodule MvWeb.Router do
   end
 
   defp set_locale(conn, _opts) do
-    locale = get_session(conn, :locale) || "de"
+    locale =
+      get_session(conn, :locale) ||
+        extract_locale_from_headers(conn.req_headers)
+
     Gettext.put_locale(MvWeb.Gettext, locale)
+
     conn
+    |> put_session(:locale, locale)
+    |> assign(:locale, locale)
   end
+
+  # Get locale from user
+  defp extract_locale_from_headers(headers) do
+    headers
+    |> Enum.find_value(fn
+      {"accept-language", value} -> value
+      _ -> nil
+    end)
+    |> parse_accept_language()
+    |> Enum.find(&supported_locale?/1)
+    |> fallback_locale()
+  end
+
+  defp parse_accept_language(nil), do: []
+
+  defp parse_accept_language(header) do
+    header
+    |> String.split(",")
+    |> Enum.map(&String.trim/1)
+    |> Enum.map(fn lang ->
+      lang
+      # we only want the first part
+      |> String.split(";")
+      |> hd()
+      |> String.split("-")
+      |> hd()
+    end)
+  end
+
+  # Our supported languages for now are german and english, english as fallback language
+  defp supported_locale?(locale), do: locale in ["en", "de"]
+  defp fallback_locale(nil), do: "en"
+  defp fallback_locale(locale), do: locale
 end