Improve login form

app/controllers/sessions_controller.rb

@@ -10,7 +10,8 @@ class SessionsController < ApplicationController
       session[:user_id] = @user.id
       redirect_to @user, notice: t(".logged_in")
     else
-      redirect_to root_path, alert: t(".login_fail")
+      flash.now.alert = t(".login_fail")
+      render :new
     end
   end
 

app/views/sessions/new.html.erb

@@ -1,5 +1,5 @@
 <% @title = "Log in" %>
-<%= form_with url: sessions_path, method: :post do |f| %>
+<%= form_with url: sessions_path, method: :post, id: "session_form" do |f| %>
   <h2><%= t ".log_in" %></h2>
 
   <%= f.label :username %>

app/views/sessions/new.turbo_stream.erb

@@ -0,0 +1,18 @@
+<% @title = "Log in" %>
+<%= turbo_stream.replace "flash_wrapper" do %>
+  <%= render "shared/flash" %>
+<% end %>
+
+<%= turbo_stream.replace "session_form" do %>
+  <%= form_with url: sessions_path, method: :post, id: "session_form" do |f| %>
+    <h2><%= t ".log_in" %></h2>
+
+    <%= f.label :username %>
+    <%= f.text_field :username %>
+
+    <%= f.label :password %>
+    <%= f.password_field :password %>
+
+    <%= f.submit t(".log_in") %>
+  <% end %>
+<% end %>