Add sequential_id to calculate auto incrementing submission id

app/models/submission.rb

@@ -2,6 +2,8 @@ class Submission < ApplicationRecord
   belongs_to :form
   has_many_attached :files
 
+  acts_as_sequenced scope: :form_id
+
   validates_presence_of :data, if: :appended_at?
 
   def process_data(submitted_data)
@@ -21,6 +23,10 @@ class Submission < ApplicationRecord
       JSON.dump(value)
     when 'tinyforms_now'
       Time.now.utc.to_formatted_s(:rfc822)
+    when 'tinyforms_token'
+      form.token
+    when 'tinyforms_id'
+      sequential_id
     when ActionDispatch::Http::UploadedFile
       # manually create the ActiveStorage attachment because we need the ID of the Attachment to create the URL
       # first the file needs to be uplaoded then we can create an Attachment