diff --git a/app/controllers/origami/discounts_controller.rb b/app/controllers/origami/discounts_controller.rb
index 79412d60..6c76c27a 100644
--- a/app/controllers/origami/discounts_controller.rb
+++ b/app/controllers/origami/discounts_controller.rb
@@ -64,9 +64,8 @@ class Origami::DiscountsController < BaseOrigamiController
       if discount_items.length > 0       
         #destroy sale item for discount
         discount_items.each do |di|          
-          sale_item = SaleItem.find(di["id"])
-          price = (sale_item.price - 0)          
-          sale.total_amount = (sale.total_amount + price)
+          sale_item = SaleItem.find(di["id"])                 
+          sale.total_amount = (sale.total_amount + sale_item.price.abs)
           sale_item.destroy
         end                 
       end  
@@ -91,9 +90,8 @@ class Origami::DiscountsController < BaseOrigamiController
                     
       #destroy all discount sale item
       sale.sale_items.each do |si|  
-        if si.remark == "Discount" && si.price < 0                   
-          price = (si.price - 0)          
-          sale.total_amount = (sale.total_amount + price)
+        if si.remark == "Discount" && si.price < 0                                   
+          sale.total_amount = (sale.total_amount + si.price.abs)
           si.destroy
         end
       end                 
diff --git a/app/views/origami/discounts/index.html.erb b/app/views/origami/discounts/index.html.erb
index 5e5a3385..8aaf5c4f 100644
--- a/app/views/origami/discounts/index.html.erb
+++ b/app/views/origami/discounts/index.html.erb
@@ -369,10 +369,19 @@ $(document).ready(function(){
 
 		// Selected Items		
 		var sale_items = get_selected_sale_items();	
+		if(sale_items.length == 0){
+			alert("You have no selected item!");
+			return;
+		}
+
 		for(var i=0;i < sale_items.length;i++){
 			if(sale_items[i].price < 0){
 				discount_items.push(sale_items[i]);
 			}
+			else {
+				alert("You have selected no discount item!");
+				return;
+			}
 		}
 
 		var params = { 'sale_id': sale_id, 'discount_items': JSON.stringify(discount_items) };