Add last_modified evaluation for PIO import

app/helpers/protocols_io_helper.rb

@@ -155,6 +155,13 @@ module ProtocolsIoHelper
     text.map { |auth| auth['name'] }.join(', ')
   end
 
+  def eval_last_modified(steps)
+    timestamps = steps.map do |step|
+      step['modified_on'] if step['modified_on'].present?
+    end
+    Time.at(timestamps.max).utc.to_datetime
+  end
+
   # Checks so that null values are returned as zero length strings
   # Did this so views arent as ugly (i avoid using if present statements)
   def not_null(attribute)

app/views/protocols/import_export/_import_json_protocol_preview_modal.html.erb

@@ -59,7 +59,7 @@
             <div class="col-xs-4">
               <label><%= t('protocols.import_export.import_modal.updated_at_label') %></label>
 
-              <% display_last_modified=Time.at(not_null(@json_object['last_modified']).to_i) %>
+              <% display_last_modified=eval_last_modified(@json_object['steps']) %>
               <%= f.text_field :last_modified, :value =>
               display_last_modified.to_s,readonly: true, class:
               "form-control" %>