Redirect to previous page after login

Closes #24

vedia.rb

@@ -134,7 +134,11 @@ post '/login' do
     session.clear
     session[:user_id] = user.id
     session[:timezone] = params[:timezone]
+    if params[:r]
+      redirect params[:r]
+    else
       redirect '/'
+    end
   else
     @error = _("Incorrect email or password.")
     erb :login
@@ -598,10 +602,11 @@ helpers do
   end
 
   def require_login
-    redirect '/login' unless current_user
+    redirect "/login?r=#{request.path}" unless current_user
   end
 
   def require_admin
+    require_login
     redirect '/' unless is_admin
   end
 

views/login.erb

@@ -14,6 +14,7 @@
     <input type="password" name="password" class="form-control">
   </div>
   <button type="submit" class="btn btn-primary"><%= _("Login") %></button>
+  <input type="hidden" name="r" value="<%= @params[:r] %>">
   <input type="hidden" name="timezone" value="UTC">
 </form>
 <p><a href="/signup"><%= _("Create account") %></a></p>

views/votes_show_unauthenticated.erb

@@ -14,6 +14,7 @@
     <input type="password" name="password" class="form-control">
   </div>
   <button type="submit" class="btn btn-primary"><%= _("Login") %></button>
+  <input type="hidden" name="r" value="votes/<%= @vote.secure_id %>">
   <input type="hidden" name="timezone" value="UTC">
 </form>