import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import cart.MyCart;

/**
 * An HTTP servlet that responds to the POST method of the HTTP protocol.
 * It clears the shopping cart, thanks the user for the order,
 * and resets the page to the BookStore's main page.
 */

public class MyReceiptServlet extends HttpServlet { 

    public void doPost(HttpServletRequest request,
                       HttpServletResponse response)
	throws ServletException, IOException
    {
        // Get the user's session and shopping cart
        HttpSession session = request.getSession(true);
        MyCart cart =
            (MyCart)session.getValue(session.getId());
        
        // If the user has no cart, create a new one
        if (cart == null) {
            cart = new MyCart();
            session.putValue(session.getId(), cart);
        }
        
        // Payment received -- invalidate the session
        session.invalidate();
        
        // set content type header before accessing the Writer
        response.setContentType("text/html");
        PrintWriter out = response.getWriter();
        
        // then write the response
        out.println("<html>" +
                    "<head><title> Receipt </title>" +
                    "<meta http-equiv=\"refresh\" content=\"4; url=" +
                    "http://" + request.getHeader("Host") +
                    "/servlet/productstore;\">" +
                    "</head>" +
                    
                    "<body  bgcolor=\"#FFFFFF\">" +
                    "<center>" +
                    "<hr> <br> &nbsp;" +
                    "<h1>" +
                    "<font size=\"+3\" color=\"red\">Duke's </font>" +
                    "<font size=\"+3\" color=\"purple\">Bookstore</font>" +
                    "</h1>" +
                    "</center>" +
                    "<br> &nbsp; <hr> <br> &nbsp;");
        
        out.println("<h3>Thank you for purchasing your books from us " +
                    request.getParameter("cardname") +
                    "<p>Please shop with us again soon!</h3>" +
                    
                    "<p><i>This page automatically resets.</i>" +

                    "</body></html>");
        out.close();
    }

    public String getServletInfo() {
        return "The Receipt servlet clears the shopping cart, " +
               "thanks the user for the order, and resets the " +
               "page to the BookStore's main page.";
    }
}