This code allow buy one get one discount functionality

1. Add the below property for the product that needs buy one get one discount:

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!DOCTYPE properties SYSTEM "http://java.sun.com/dtd/properties.dtd">
<properties>
    <entry key="BOGO">2</entry> 
</properties>

Here the value of BOGO is the number of product which will be discounted. Enter 0 for no discount, 2 for buy one get one, 3 for buy two get one and so on.

Administrator Menu > Maintenance > Resources
2. Enable the event ticket.change in the resource Ticket.Buttons

3. Create a new resource event.change and add the below code:

//BOGO Functionality

index = sales.getSelectedIndex();
if (index != -1) 
{
    line = ticket.getLine(index);
    int bogo = Integer.parseInt(line.getProperty("BOGO","0"));
    if (bogo > 0) 
    {
  int product_count = 0;
  String productID = line.getProductID();
  for (i = 0; i < ticket.getLinesCount(); i++) 
        {
   if ((productID.equals(ticket.getLine(i).getProductID()) != null) && (Integer.parseInt(ticket.getLine(i).getProperty("BOGO","0")) > 0)) 
            {
    product_count++;
   }
  }
        if (bogo == product_count) 
        {
            sales.addItemByCode(line.printCode(),1);
            line = ticket.getLine(ticket.getLinesCount()-1);
            line.setSalePrice(0);
            
            /* Remove BOGO property to start fresh */
   for (i = 0; i < ticket.getLinesCount(); i++) {
    if (productID.equals(ticket.getLine(i).getProductID()) != null) {
     ticket.getLine(i).setProperty("BOGO","0");
    }
   }
            sales.setSelectedIndex(ticket.getLinesCount()-1);
        }
    }
}

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