loads input option partials on type change

app/assets/javascripts/admin.js

@@ -1,10 +1,16 @@
 $(function(){
 
-  $("[data-id=input_option_adder]").on('click', function(){
+  $("form").on('click', "[data-id=input_option_adder]", function(){
     var $new_li = $(this).siblings('li').clone();
     $new_li.attr('style', '');
     $("[data-id=input_option_list]").append($new_li);
     $new_li.find('input').focus();
   });
 
+  $("#question_input_type").on('change', function(){
+    var qid = $(this).attr('data-qid') === undefined ? '' : "/" + $(this).attr('data-qid');
+                                            // /admin/question(/:question_id)/options/:input_type
+    $("[data-id=input-options-wrapper]").load("/admin/question" + qid + "/options/" + $(this).val());
+  });
+
 });

app/controllers/admin/question_controller.rb

@@ -43,6 +43,11 @@ module Admin
       end
     end
 
+    def options
+      @question = params[:question_id].present? ? Question.find(params[:question_id]) : Question.new
+      render layout: false
+    end
+
     private
 
       def question_params

app/views/admin/question/_form.html.erb

@@ -27,13 +27,15 @@
 
   <div class="form-group">
     <%= form.label :input_type, 'Input Type' %>
-    <%= form.select :input_type, question_type_options(question.input_type), include_blank: false %>
+    <%= form.select :input_type, question_type_options(question.input_type), { include_blank: false }, { data: { qid: question.id } } %>
   </div>
 
+  <div class="form-group" data-id="input-options-wrapper">
     <%= fields_for @question do |fields| %>
       <% partial = question.input_type.blank? ? 'admin/question/text' : "admin/question/#{question.input_type}" %>
       <%= render partial: partial, locals: {question: question, fields: fields } %>
     <% end %>
+  </div>
 
   <%= form.submit %>
 <% end %>

app/views/admin/question/options.html.erb

@@ -0,0 +1,5 @@
+<%
+  if lookup_context.exists?(params[:input_type], 'admin/question', true)
+    %><%= render partial: "admin/question/#{params[:input_type]}", locals: { question: @question } %><%
+  end
+%>

app/views/admin/question/view.html.erb

@@ -33,4 +33,6 @@
   <% end %>
 
   <%= link_to('Edit', admin_edit_question_path(@question.to_i), { class: 'btn' }) %>
+
+  <%= link_to('View Quiz', admin_quiz_path(@question.quiz_id), { class: 'btn' }) %>
 </main>

config/routes.rb

@@ -24,6 +24,7 @@ Rails.application.routes.draw do
   get   "/admin/questions",                                   to: "admin/question#index",   as: :admin_questions
   get   "/admin/question/new",                                to: "admin/question#new",     as: :admin_new_question
   post  "/admin/question/new",                                to: "admin/question#create",  as: :admin_create_question
+  get   "/admin/question(/:question_id)/options/:input_type", to: "admin/question#options", as: :admin_question_option_form
   get   "/admin/question/:question_id",                       to: "admin/question#view",    as: :admin_question
   get   "/admin/question/:question_id/edit",                  to: "admin/question#edit",    as: :admin_edit_question
   post  "/admin/question/:question_id/edit",                  to: "admin/question#update",  as: :admin_update_question

test/controllers/admin/question_controller_test.rb

@@ -72,5 +72,20 @@ module Admin
       assert :success
       assert_match(/failed/i, session[:flash].values.join)
     end
+
+    test "should gracefully fail input_type" do
+      get admin_question_option_form_url(input_type: 'fooBarBaz')
+
+      assert :success
+      assigns :locals
+    end
+
+    test "should return partial for new radio" do
+      get admin_question_option_form_url(input_type: 'radio')
+
+      assert :success
+      assigns :locals
+      assert_select "input[id^=question_multi_choice_]"
+    end
   end
 end