Markdown editor for DraftVersion body

app/assets/javascripts/application.js

@@ -46,6 +46,8 @@
 //= require embed_video
 //= require banners
 //= require social_share
+//= require markdown-it
+//= require markdown_editor
 //= require custom
 
 var initialize_modules = function() {
@@ -68,6 +70,7 @@ var initialize_modules = function() {
   App.EmbedVideo.initialize();
   App.Banners.initialize();
   App.SocialShare.initialize();
+  App.MarkdownEditor.initialize();
 };
 
 $(function(){

app/assets/javascripts/markdown_editor.js.coffee

@@ -0,0 +1,20 @@
+App.MarkdownEditor =
+
+  refresh_preview: (element, md) ->
+    textarea_content = element.find('textarea').val()
+    result = md.render(textarea_content)
+    element.find('#markdown-preview').html(result)
+
+  initialize: ->
+    $('.markdown-editor').each ->
+      md = window.markdownit({
+        html: true,
+        breaks: true,
+        typographer: true,
+      })
+      App.MarkdownEditor.refresh_preview($(this), md)
+      $(this).on 'change input paste keyup', ->
+        App.MarkdownEditor.refresh_preview($(this), md)
+        return
+
+