/*
 * Created on August 11, 2005, 9:38 AM
 */

package com.mycompany;

import java.io.*;
import java.net.*;

import javax.servlet.*;
import javax.servlet.http.*;

/**
 *
 * @author  JohnN
 * @version
 */
/*

This servlet uses cookies to store data entered in the form by the
user from the ITProducts.Com Registration Page and to make the form
data available for display.

The original page displayed by the servlet is the ITProducts.Com
Registration Page, which displays the form.

If the user presses Submit from the ITProducts.Com Registration Page,
error checking is performed to determine whether data is entered and
whether entered data is correct.

- If so, the data is displayed in the ITProducts.Com Confirmation Page.
  From here, the user can click Edit to return to the form. The form
  is now called the ITProducts.Com Edit Page.

- If not, the form is redisplayed with any entered data and appropriate
  error messages. The form is now called the ITProducts.Com Edit Page.

If the user presses Reset from the ITProducts Registration Page,
the ITProducts.Com Registration page is redisplayed with all form data
restored to their original values.

*/

import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class CookieSelfHandlingForm extends HttpServlet
{
   public void doGet
      (HttpServletRequest req, HttpServletResponse res)
                    throws ServletException, IOException
   {
      // Create variables
      // The value of pagetype is either "Registration" or "Edit"
      // The Registration page is the form when first displayed or after Reset is pressed
      // The Edit page is the same form after Submit is pressed and error messages are displayed
      // Note that if Submit is pressed and all values are entered correctly,
      // a new Confirmation page is displayed by the doPost method
      String pagetype;
      // Variables for form data
      String username, email, occupation, region, otherregionname, newproducts, specialoffers;
      // The value of these variables control what happens in the doPost method
      String reset, submit;

      // Initialize variables
      pagetype = "";
      username = null;
      email = null;
      occupation = "";
      region = "";
      otherregionname = null;
      newproducts = "";
      specialoffers = "";
      reset = "";
      submit = "";

      res.setContentType("text/html");
      PrintWriter out = res.getWriter();

      // Set up a cookie array
      Cookie[] cookies = req.getCookies();

      // See if there are any cookies in array, that is, check that array is not null
      try
      {
         // If cookies in array, then this is the Edit page
         // Obtain all values
         for (int i = 0; i <cookies.length; i++)
         {
         if    (cookies[i].getName().equals("username"))
               username = cookies[i].getValue();
            else if
               (cookies[i].getName().equals("email"))
               email = cookies[i].getValue();
            else if
               (cookies[i].getName().equals("occupation"))
               occupation = cookies[i].getValue();
            else if
               (cookies[i].getName().equals("region"))
               region = cookies[i].getValue();
            else if
               (cookies[i].getName().equals("otherregionname"))
               otherregionname = cookies[i].getValue();
            else if
               (cookies[i].getName().equals("newproducts"))
               newproducts = cookies[i].getValue();
            else if
               (cookies[i].getName().equals("specialoffers"))
               specialoffers = cookies[i].getValue();
            else if
               (cookies[i].getName().equals("reset"))
               reset = cookies[i].getValue();
            else if
               (cookies[i].getName().equals("submit"))
               submit = cookies[i].getValue();
         }
         // After Reset, this is the Registration page
         if (reset.equals("reset"))
            pagetype = "Registration";
         else
            pagetype = "Edit";
      }
      catch (NullPointerException e)
      {
         // If no cookies in array, this is the Registration page
         pagetype = "Registration";
      }

      // HTML document
      out.println("<html>");
      out.println("<head>");
      out.println("<title>ITProducts.Com " + pagetype + " Page</title>");
      out.println("<head>");
      out.println("<body>");
      out.println("<h1>ITProducts.Com " + pagetype + " Page</h1>");
      out.println("<form method=\"POST\" action=\"CookieSelfHandlingForm\">");

      out.println("<table border=\"0\">");

      // Username
      out.println("<tr>");
      out.println("<td>Name:</td>");
      out.print("<td><input type=\"text\" name=\"username\" size=\"40\"");
      if (username != null)
         out.print(" value=\"" + username + "\"");
      out.print(">");
      out.println("</td>");
      out.println("</tr>");
      // Error message if no username entered
      if (submit.equals("submit") && username.equals(""))
      {
         out.println("<tr>");
         out.println("<td></td>");
         out.println("<td><strong>Please type your username.</strong></td>");
         out.println("</tr>");
      }

      // Email
      out.println("<tr>");
      out.println("<td>Email address:</td>");
      out.print("<td><input type=\"text\" name=\"email\" size=\"40\"");
      if (email != null)
         out.print(" value=\"" + email + "\"");
      out.print(">");
      out.println("</td>");
      out.println("</tr>");
      // Error message if no email address entered
      if (submit.equals("submit") && email.equals(""))
      {
         out.println("<tr>");
         out.println("<td></td>");
         out.println("<td><strong>Please type your email address.</strong></td>");
         out.println("</tr>");
      }

      // Occupation
      out.println("<tr>");
      out.println("<td>Occupation:</td>");
      out.println("<td><select name=\"occupation\">");
      out.println("<option value=\"choose\"");
      if (occupation.equals("choose"))
         out.print(" selected");
      out.println(">Choose your occupation</option>");
      out.println("<option value=\"prog\"");
      if (occupation.equals("prog"))
         out.print(" selected");
      out.println(">Programmer</option>");
      out.println("<option value=\"netadmin\"");
      if (occupation.equals("netadmin"))
         out.print(" selected");
      out.println(">Network Administrator</option>");
      out.println("<option value=\"webdev\"");
      if (occupation.equals("webdev"))
         out.print(" selected");
      out.println(">Web Developer</option>");
      out.println("<option value=\"itman\"");
      if (occupation.equals("itman"))
         out.print(" selected");
      out.println(">IT Manager</option>");
      out.println("<option value=\"other\"");
      if (occupation.equals("other"))
         out.print(" selected");
      out.println(">Other</option></td>");
      out.println("</tr>");
      // Error message if no occupation chosen
      if (submit.equals("submit") && occupation.equals("choose"))
      {
         out.println("<tr>");
         out.println("<td></td>");
         out.println("<td><strong>Please choose your occupation.</strong></td>");
         out.println("</tr>");
      }

      out.println("<table>");

      // Region
      out.println("<p>");
      out.println("Region:<br>");
      out.println("<input type=\"radio\" name=\"region\" value=\"usregion\"");
      if (region.equals("usregion"))
         out.print(" checked");
      out.println(">North America<br>");
      out.println("<input type=\"radio\" name=\"region\" value=\"apregion\"");
      if (region.equals("apregion"))
         out.print(" checked");
      out.println(">Asia Pacific<br>");
      out.println("<input type=\"radio\" name=\"region\" value=\"euregion\"");
      if (region.equals("euregion"))
         out.print(" checked");
      out.println(">Europe<br>");
      out.println("<input type=\"radio\" name=\"region\" value=\"otherregion\"");
      if (region.equals("otherregion"))
         out.print(" checked");
      out.println(">Other, please specify");
      out.println("<input type=\"text\" name=\"otherregionname\" size=\"40\"");
      if (otherregionname != null)
         out.print(" value=\"" + otherregionname + "\" ");
      out.println(">");
      out.println("</p>");
      // Error message if region combination incorrect
      if (submit.equals("submit")) // The Submit button was pressed
      {
         if (region.equals("")) // No region was selected
         {
            if (otherregionname.equals("")) // No region name was entered
               out.println("<p><strong>Please click either a specific Region or Other.</strong></p>");
            else // A region name was entered
               out.println("<p><strong>If you type another region name, you must also click Other.</strong></p>");
         }
         else if (region.equals("otherregion")) // Other was selected
         {
            if (otherregionname.equals("")) // A region name was not entered
               out.println("<p><strong>If you click Other, you must also type the region name.</strong></p>");
         }
         else // A specific region was selected
         {
            if (!otherregionname.equals("")) // A region name was entered
               out.println("<p><strong>If you click a specific Region, you cannot type another region name.</strong></p>");
         }
      }

      // New Products
      out.println("<p>");
      out.println("<input type=\"checkbox\" name=\"newproducts\" value=\"on\"");
      if (newproducts.equals("on"))
         out.print(" checked");
      out.println(">Subscribe to new products email list.<p>");

      // Special Offers
      out.println("<p>");
      out.println("<input type=\"checkbox\" name=\"specialoffers\" value=\"on\"");
      if (specialoffers.equals("on"))
         out.print(" checked");
      out.println(">Subscribe to special offers email list.");
      out.println("</p>");

      out.println("<p>");
      // Genuine Submit button to submit the form
      // The button is trapped and error checking is performed is doPost method
      out.println("<input type=\"submit\" name=\"submit\" value=\"submit\">");
      // Fake Reset button (using a submit action) to reset the form
      // The button is trapped and values are set to defaults in doPost method
      out.println("<input type=\"submit\" name=\"reset\" value=\"reset\">");
      out.println("</p>");

      out.println("</form>");

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

   public void doPost
      (HttpServletRequest req, HttpServletResponse res)
                    throws ServletException, IOException
   {
      // Create variables
      String pagetype;
      String username, email, occupation, region, otherregionname, newproducts, specialoffers;
      String reset, submit;
      String newURL = res.encodeRedirectURL("CookieSelfHandlingForm");

      // Get values of form data
      pagetype = req.getParameter("pagetype");
      username = req.getParameter("username");
      email = req.getParameter("email");
      occupation = req.getParameter("occupation");
      region = req.getParameter("region");
      if (region == null)
         region = "";
      otherregionname = req.getParameter("otherregionname");
      newproducts = req.getParameter("newproducts");
      if (newproducts == null)
         newproducts = "";
      specialoffers = req.getParameter("specialoffers");
      if (specialoffers == null)
         specialoffers = "";
      reset = req.getParameter("reset");
      if (reset == null)
         reset = "";
      submit = req.getParameter("submit");
      if (submit == null)
         submit = "";

      // Create cookies from form data, to expire when session finishes
      Cookie myCookie;
      myCookie = new Cookie("pagetype",pagetype);
      myCookie.setMaxAge(-1);
      res.addCookie(myCookie);
      myCookie = new Cookie("username",username);
      myCookie.setMaxAge(-1);
      res.addCookie(myCookie);
      myCookie = new Cookie("email",email);
      myCookie.setMaxAge(-1);
      res.addCookie(myCookie);
      myCookie = new Cookie("occupation",occupation);
      myCookie.setMaxAge(-1);
      res.addCookie(myCookie);
      myCookie = new Cookie("region",region);
      myCookie.setMaxAge(-1);
      res.addCookie(myCookie);
      myCookie = new Cookie("otherregionname",otherregionname);
      myCookie.setMaxAge(-1);
      res.addCookie(myCookie);
      myCookie = new Cookie("newproducts",newproducts);
      myCookie.setMaxAge(-1);
      res.addCookie(myCookie);
      myCookie = new Cookie("specialoffers",specialoffers);
      myCookie.setMaxAge(-1);
      res.addCookie(myCookie);
      myCookie = new Cookie("reset",reset);
      myCookie.setMaxAge(-1);
      res.addCookie(myCookie);
      myCookie = new Cookie("submit",submit);
      myCookie.setMaxAge(-1);
      res.addCookie(myCookie);

      // Trap Submit button and do some error checking
      if (submit.equals("submit") // The Submit button was pressed
         &&
         (username.equals("") || // No user name was entered
          email.equals("") || // No email address was entered
          occupation.equals("choose") || // No occupation was selected
          region.equals("") || // No region was selected
          // Other was selected but a region name was not entered
          (region.equals("otherregion") && otherregionname.equals("")) ||
          // A specific region was selected and a region name was entered
          (!region.equals("") && !region.equals("otherregion") && !otherregionname.equals(""))))
         res.sendRedirect(newURL);

      // Trap Reset button and explicitly set form values to defaults by expiring all cookies
      if (reset.equals("reset"))
      {
         myCookie = new Cookie("pagetype",pagetype);
         myCookie.setMaxAge(0);
         res.addCookie(myCookie);
         myCookie = new Cookie("username",username);
         myCookie.setMaxAge(0);
         res.addCookie(myCookie);
         myCookie = new Cookie("email",email);
         myCookie.setMaxAge(0);
         res.addCookie(myCookie);
         myCookie = new Cookie("occupation",occupation);
         myCookie.setMaxAge(0);
         res.addCookie(myCookie);
         myCookie = new Cookie("region",region);
         myCookie.setMaxAge(0);
         res.addCookie(myCookie);
         myCookie = new Cookie("otherregionname",otherregionname);
         myCookie.setMaxAge(0);
         res.addCookie(myCookie);
         myCookie = new Cookie("newproducts",newproducts);
         myCookie.setMaxAge(0);
         res.addCookie(myCookie);
         myCookie = new Cookie("specialoffers",specialoffers);
         myCookie.setMaxAge(0);
         res.addCookie(myCookie);
         myCookie = new Cookie("reset",reset);
         myCookie.setMaxAge(0);
         res.addCookie(myCookie);
         myCookie = new Cookie("submit",submit);
         myCookie.setMaxAge(0);
         res.addCookie(myCookie);
         // Using setStatus and setHeader because using res.sendRedirect caused
         // an IllegalStateException in Apache Tomcat 4.0.4 if the Reset button
         // was clicked when all field were set to their default values.
         // See http://www.jguru.com/faq/view.jsp?EID=53251
         res.setStatus(HttpServletResponse.SC_MOVED_PERMANENTLY);
         res.setHeader("Location",newURL);
      }

      res.setContentType("text/html");
      PrintWriter out = res.getWriter();

      // HTML document
      out.println("<html>");
      out.println("<head>");
      out.println("<title>ITProducts.Com Confirmation Page</title>");
      out.println("<head>");
      out.println("<body bgcolor=\"cccccc\">");
      out.println("<h1>ITProducts.Com Confirmation Page</h1>");
      out.println("<h2>You provided the following information:</h2>");

      // Username
      out.print("<p>Name: ");
      out.print("<strong>");
      out.print(username);
      out.print("</strong>");
      out.println("</p>");

      // Email
      out.print("<p>Email: ");
      out.print("<strong>");
      out.print(email);
      out.print("</strong>");
      out.println("</p>");

      // Occupation
      out.print("<p>Occupation: ");
      out.print("<strong>");
      if (occupation.equals("choose")) // Not really needed
         out.print("");
      else if (occupation.equals("prog"))
         out.print("Programmer");
      else if (occupation.equals("netadmin"))
         out.print("Network Administrator");
       else if (occupation.equals("webdev"))
         out.print("Web Developer");
       else if (occupation.equals("itman"))
         out.print("IT Manager");
       else if (occupation.equals("other"))
         out.print("Other");
       out.print("</strong>");
       out.println("</p>");

      // Region
      out.print("<p>Region: ");
      out.print("<strong>");
      if (region.equals("usregion"))
         out.print("North America");
      else if (region.equals("apregion"))
         out.print("Asia Pacific");
      else if (region.equals("euregion"))
         out.print("Europe");
      else if (region.equals("otherregion"))
         if (otherregionname.equals("")) // Not really needed
            out.print("Other region, not specified");
         else
            out.print(otherregionname);
      out.print("</strong>");
      out.println("</p>");

      // New Products
      out.print("<p>Subscribe to new products email list: ");
      out.print("<strong>");
      if (newproducts.equals("on"))
         out.print("Yes");
      else
         out.print("No");
      out.print("</strong>");
      out.println("</p>");

      // Special Offers
      out.println("<p>Subscribe to special offers email list: ");
      out.print("<strong>");
      if (specialoffers.equals("on"))
         out.print("Yes");
      else
         out.print("No");
      out.print("</strong>");
      out.println("</p>");

      out.println("<p>");
      out.print("<strong>");
      out.print("<a href=\"" + newURL + "\">Edit</a>");
      out.print("</strong>");
      out.println("</p>");

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