Add fallback for last service date and introduce 'unknown' label

app/views/vehicles/_details.html.erb

@@ -49,6 +49,18 @@
   </div>
 </div>
 
+<% last = vehicle.issues.last %>
+<% if last %>
+  <% mileage = last.custom_values.find_by(custom_field_id: CustomField.find_by_name("Mileage").id) %>
+  <% if mileage %>
+    <p>
+      <b><%=t(:label_last_service) %></b> <%= last&.closed_on&.to_date || l(:label_unknown) %>
+      at <%= mileage.value %>
+      <%=t(:label_miles) %>
+    </p>
+  <% end %>
+<% end %>
+
 <div style="float: right;">
   <%= button_to t(:label_edit), edit_vehicle_path(vehicle), method: :get%> 
   <%= button_to t(:label_delete), vehicle, method: :delete, data: {confirm: t(:warn_ru_sure)} %> 

config/locales/en.yml

@@ -24,11 +24,15 @@ en:
   label_customer_vehicles: "Customer Vehicles"
   label_edit: "Edit"
   label_edit_customer_vehicle: "Edit Customer Vehicle"
+  label_last_service: "Last Serviced:"
   label_make: "Make"
+  label_miles: "miles"
   label_model: "Model"
   label_new_vehicle: "New Customer Vehicle"
   label_no_vehicles: "There are no vehicles containing the term(s)"
   label_search_vehicles: "Search Vehicles"
+  label_unknown: "Unknown"
+  label_vehicle: "Vehicle"
   label_year: "Year"
   no_customer: "Customer no longer exists"
   notice_decoding_vin: "Decoding VIN… this page will update automatically."