update conflix for request bill

app/models/sale.rb

@@ -78,12 +78,25 @@ class Sale < ApplicationRecord
       self.tax_type = "exclusive"
 
       # set cashier
-      if cashier != nil
+      open_cashier = Employee.where("role = 'cashier' AND token_session <> ''")
+      current_shift = ShiftSale.current_shift
+      shift = ShiftSale.current_open_shift(cashier.id)
+
+      # set cashier
+      if shift != nil
         self.cashier_id = cashier.id
         self.cashier_name = cashier.name
+        self.shift_sale_id = shift.id
       else
-        self.cashier_id = requested_by.id
-        self.cashier_name = requested_by.name
+        if open_cashier.nil?
+          self.cashier_id   = requested_by.id
+          self.cashier_name = requested_by.name
+          self.shift_sale_id = current_shift.id
+        else
+          self.cashier_id   = current_shift.employee_id
+          self.cashier_name = Employee.find(current_shift.employee_id).name
+          self.shift_sale_id = current_shift.id
+        end
       end
 
       # set waiter