heck rounding adjustment error

app/models/sale.rb

@@ -470,8 +470,24 @@ class Sale < ApplicationRecord
   end
 
   def adjust_rounding
-    self.grand_total
-    self.rounding_adjustment = 0.00
+    saleObj = Sale.find(self.sale_id)
+    shop_details =  Shop::ShopDetail 
+      # rounding adjustment
+    if shop_details.is_rounding_adj
+      a = saleObj.grand_total % 25 # Modulus
+      b = saleObj.grand_total / 25 # Division
+      #not calculate rounding if modulus is 0 and division is even
+      #calculate rounding if modulus is zero or not zero and division are not even
+      if (a != 0.0 && b%2 != 0.0) || (a==0.0 && b%2 !=0)
+        new_total    = Sale.get_rounding_adjustment(saleObj.grand_total)
+        self.rounding_adjustment = new_total-saleObj.grand_total
+      else
+        self.rounding_adjustment = 0.00
+      end
+    else
+      self.rounding_adjustment = 0.00
+    end
+    
   end
 
   #Generate new Receipt No when it is not assigned