Fixes #3827 - Ticket create screen will loose attachments by time.

app/assets/javascripts/app/controllers/_ui_element/richtext.coffee

@@ -27,6 +27,8 @@ class App.UiElement.richtext
       renderFile = (file) ->
         item.find('.attachments').append(App.view('generic/attachment_item')(file))
         attachments.push file
+        if form.richTextUploadRenderCallback
+          form.richTextUploadRenderCallback(attribute, attachments)
 
       if params && params.attachments
         for file in params.attachments
@@ -54,6 +56,8 @@ class App.UiElement.richtext
             return if item.id.toString() is id.toString()
             item
         )
+        if form.richTextUploadDeleteCallback
+          form.richTextUploadDeleteCallback(attribute, attachments)
 
         form_id = item.closest('form').find('[name=form_id]').val()
 

app/assets/javascripts/app/controllers/agent_ticket_create.coffee

@@ -283,6 +283,13 @@ class App.TicketCreate extends App.Controller
     return if !@formMeta
     App.QueueManager.run(@queueKey)
 
+  updateTaskManagerAttachments: (attribute, attachments) =>
+    taskData = App.TaskManager.get(@taskKey)
+    return if _.isEmpty(taskData)
+
+    taskData.attachments = attachments
+    App.TaskManager.update(@taskKey, taskData)
+
   render: (template = {}) ->
     return if !@formMeta
     # get params
@@ -379,6 +386,8 @@ class App.TicketCreate extends App.Controller
       handlersConfig: handlersTunnel
       params:  params
       taskKey: @taskKey
+      richTextUploadRenderCallback: @updateTaskManagerAttachments
+      richTextUploadDeleteCallback: @updateTaskManagerAttachments
     )
     @controllerFormCreateBottom = new App.ControllerForm(
       el:             @$('.ticket-form-bottom')

spec/system/ticket/create_spec.rb

@@ -779,4 +779,39 @@ RSpec.describe 'Ticket Create', type: :system do
       end
     end
   end
+
+  describe 'Ticket create screen will loose attachments by time #3827' do
+    before do
+      visit 'ticket/create'
+    end
+
+    it 'does not loose attachments on rerender of the ui' do
+      # upload two files
+      page.find('input#fileUpload_1', visible: :all).set(Rails.root.join('test/data/mail/mail001.box'))
+      await_empty_ajax_queue
+      page.find('input#fileUpload_1', visible: :all).set(Rails.root.join('test/data/mail/mail002.box'))
+      await_empty_ajax_queue
+      wait(5).until { page.all('div.attachment-delete.js-delete', visible: :all).count == 2 }
+      expect(page).to have_text('mail001.box')
+      expect(page).to have_text('mail002.box')
+
+      # remove last file
+      begin
+        page.evaluate_script("$('div.attachment-delete.js-delete:last').click()") # not interactable
+      rescue # Lint/SuppressedException
+        # because its not interactable it also
+        # returns this weird exception for the jquery
+        # even tho it worked fine
+      end
+      await_empty_ajax_queue
+      wait(5).until { page.all('div.attachment-delete.js-delete', visible: :all).count == 1 }
+      expect(page).to have_text('mail001.box')
+      expect(page).to have_no_text('mail002.box')
+
+      # simulate rerender b
+      page.evaluate_script("App.Event.trigger('ui:rerender')")
+      expect(page).to have_text('mail001.box')
+      expect(page).to have_no_text('mail002.box')
+    end
+  end
 end