package org.paneris.jammyjoes.shopping;

 import java.util.Enumeration;

 import java.util.Iterator;

 import java.util.LinkedList;

 import java.util.List;

 import javax.servlet.ServletConfig;

 import javax.servlet.ServletException;

 import org.melati.Melati;

 import org.melati.servlet.Form;

 import org.melati.poem.Field;

 import org.melati.servlet.InvalidUsageException;

 import org.melati.PoemContext;

 import org.melati.servlet.PathInfoException;

 import org.melati.servlet.TemplateServlet;

 import org.melati.template.ServletTemplateContext;

 import org.melati.util.InstantiationPropertyException;

 import org.melati.util.MelatiException;

 import org.paneris.jammyjoes.model.JammyjoesDatabase;

 import org.paneris.jammyjoes.mvp.CatalogueEntryPresenter;

 import org.paneris.jammyjoes.mvp.Context;

 import org.paneris.jammyjoes.mvp.ContextWrapper;

 import org.paneris.jammyjoes.mvp.Presenter;

 import org.paneris.jammyjoes.util.JammyJoesContextUtil;

 import org.paneris.jammyjoes.util.JammyJoesUtil;

 /** 

  * The Melati Shopping Trolley Interface is designed to provide 

  * a flexible adstraction of the basic processes of allowing 

  * customers to buy goods on a website. 

  * By default, it is not integrated with POEM, and so makes 

  * no assumptions about

  * the underlying database implementaion.

  *

  * Please read the readme.txt file for full instructions.

  *

  * The Trolley is a servlet that handles the user's interaction with 

  * the Shopping Trolley.

  *

  * @see org.paneris.melati.shopping.ShoppingTrolley

  * @see org.paneris.melati.shopping.ShoppingTrolleyItem

  * @see org.paneris.melati.shopping.DefaultShoppingTrolley

  * @see org.paneris.melati.shopping.DefaultShoppingTrolleyItem

  *

  **/

 public class Trolley extends TemplateServlet {

   private static final long serialVersionUID = 1L;

   public MelatiShoppingConfig config;

   /**

    * Inititialise the Shopping Trolley Engine.  This will load a file called

    * org.paneris.melati.shopping.ShoppingTrolley.properties in order to 

    * find the classes that implement this shopping implementation

    *

    * @param conf - the Servlet's config parameters

    * @see org.paneris.melati.shopping.MelatiShoppingConfig

    **/

   public void init(ServletConfig conf ) throws ServletException

   {

      super.init(conf );

      try {

        config = new MelatiShoppingConfig();

      } catch (MelatiException e) {

        throw new ServletException(e.toString());

      }

   }

   public String getSysAdminName() {

     return "Tim Joyce";

   }

   public String getSysAdminEmail() {

     return "timj@hoop.co.uk";

   }

   /**

    * Main entry point for this servlet

    *

    * @param melati - the melati for this request

    * @param context - the Template Context for this request

    *

    * @return - the name of the template to be returned to the user

    *

    * @throws InvalidUsageException - if this request has an invalid form

    **/

   protected String doTemplateRequest(Melati melati, ServletTemplateContext context)

       throws Exception {

     if (config==null) 

        throw new ShoppingConfigException("Shopping Trolley not Configured");

     JammyjoesDatabase db = (JammyjoesDatabase) melati.getDatabase();

     context.put("menutypes", db.getTypeTable().selection());

     context.put("jjutil", new JammyJoesContextUtil());

     if (JammyJoesUtil.telesales(melati)) assertLogin(melati);

     ShoppingContext shoppingContext = (ShoppingContext)melati.getPoemContext();

     if (shoppingContext.getMethod().equals("Load")) 

       return Load(melati, shoppingContext.stid);

     if (shoppingContext.getMethod().equals("View")) return View(melati);

     if (shoppingContext.getMethod().equals("Update")) return Update(melati);

     if (shoppingContext.getMethod().equals("Add")) 

       return Add(melati, shoppingContext.stid, shoppingContext.quantity);

     if (shoppingContext.getMethod().equals("MultipleAdd")) 

       return MultipleAdd(melati);

     if (shoppingContext.getMethod().equals("Remove")) 

       return Remove(melati, shoppingContext.stid);

     if (shoppingContext.getMethod().equals("Set")) 

       return Set(melati, shoppingContext.stid, shoppingContext.quantity);

     if (shoppingContext.getMethod().equals("Details")) return Details(melati);

     if (shoppingContext.getMethod().equals("Confirm")) return Confirm(melati);

     if (shoppingContext.getMethod().equals("Paid")) return Paid(melati);

     if (shoppingContext.getMethod().equals("Abandon")) return Abandon(melati);

     if (shoppingContext.getMethod().equals("CatalogueEntry")) return CatalogueEntry(melati);

     throw new InvalidUsageException(this, shoppingContext);

   }

   /** 

    * load the trolley from something persistent

    *

    * @param melati - the melati for this request

    * @param id - an id that can be used to identify the trolley to be loaded

    *

    * @return - "Trolley" - the page where users manipulate their 

    *           Shopping Trolley

    *

    * @throws InstantiationPropertyException - if we cannot construct trolley

    **/

   protected String Load(Melati melati, Integer id)

    throws InstantiationPropertyException {

     ShoppingTrolley trolley = ShoppingTrolley.newTrolley(config);

     trolley.initialise(melati,config,id);

     melati.getTemplateContext().put("trolley", trolley);

     return JammyJoesUtil.shoppingTemplate(melati, "Trolley");

   }

   /** 

    * load the trolley from something persistent

    *

    * @param melati - the melati for this request

    *

    * @return - "Trolley" - the page where users manipulate their 

    *           Shopping Trolley

    *

    * @throws InstantiationPropertyException - if we cannot construct trolley

    **/

   protected String Save(Melati melati)

    throws InstantiationPropertyException {

     ShoppingTrolley trolley = ShoppingTrolley.getInstance(melati,config);

     trolley.save();

     melati.getTemplateContext().put("trolley", trolley);

     return JammyJoesUtil.shoppingTemplate(melati, "Trolley");

   }

   /** 

    * view the trolley

    *

    * @param melati - the melati for this request

    *

    * @return - "Trolley" - the page where users manipulate their 

    *           Shopping Trolley

    *

    * @throws InstantiationPropertyException - if we cannot construct the trolley

    **/

   protected String CatalogueEntry(Melati melati)

    throws InstantiationPropertyException {

      JammyjoesDatabase db = (JammyjoesDatabase) melati.getDatabase();

      Context context = new ContextWrapper(melati.getServletTemplateContext());

      Presenter presenter = new CatalogueEntryPresenter(db.getProductTable(),context);

      presenter.handleInteraction(presenter.createSelection(), presenter.createCommand());

      context.put("type", new Field(null, db.getProductTable().getTypeColumn()));

      context.put("jjutil", new JammyJoesContextUtil());

      context.put("trolley", ShoppingTrolley.getInstance(melati,config));

      context.put("ages", db.getAgeTable().selection());

      return JammyJoesUtil.shoppingTemplate(melati, "CatalogueEntry");

   }

   /** 

    * view the trolley

    *

    * @param melati - the melati for this request

    *

    * @return - "Trolley" - the page where users manipulate their 

    *           Shopping Trolley

    *

    * @throws InstantiationPropertyException - if we cannot construct the trolley

    **/

   protected String View(Melati melati)

    throws InstantiationPropertyException {

     melati.getTemplateContext().put("trolley", ShoppingTrolley.getInstance(melati,config));

     return JammyJoesUtil.shoppingTemplate(melati, "Trolley");

   }

   /** 

    * update the entire trolley, changing quantities

    * and removing items.  the POSTed form is analysed for fields with names of 

    * the form:

    *

    * trolleyitem_<item id>_quantity - the new quantity of the item (if set)

    * trolleyitem_<item id>_deleted - remove this item from the trolley (if set)

    *

    * items will also be deleted if the quantity is set to 0

    *

    * @param melati - the melati for this request

    *

    * @return - "Trolley" - the page where users manipulate their 

    *           Shopping Trolley

    *

    * @throws InstantiationPropertyException - if we cannot construct the trolley

    */

   protected String Update(Melati melati) throws InstantiationPropertyException {

     ShoppingTrolley trolley = ShoppingTrolley.getInstance(melati,config);

     List removeItems = new LinkedList();

     for (Enumeration c = trolley.getItems(); c.hasMoreElements();) {

       ShoppingTrolleyItem item = (ShoppingTrolleyItem)c.nextElement();

       String formName = "trolleyitem_" + item.getId();

       String formQuantity = formName + "_quantity";

       String formDeleted = formName + "_deleted";

       String deleted = 

              Form.getFormNulled(melati.getServletTemplateContext(),formDeleted);

       String quantity = 

              Form.getFormNulled(melati.getServletTemplateContext(),formQuantity);

       System.err.println(deleted + " " + quantity);

       if (deleted != null || quantity == null || quantity.equals("0")) {

         removeItems.add(item);

       } else {

         item.setQuantity(new Integer(quantity));

       }

     }

     Iterator removeItemsIterator = removeItems.iterator();

     while (removeItemsIterator.hasNext()) {

         ShoppingTrolleyItem element = (ShoppingTrolleyItem) removeItemsIterator.next();

       trolley.removeItem(element);

       }

     melati.getTemplateContext().put("trolley",trolley);

     return JammyJoesUtil.shoppingTemplate(melati, "Trolley");

   }

   /** 

    * add multiple items to the trolley, 

    * or add to the quantities already in the 

    * trolley.  

    * The POSTed form is analysed for fields with names of 

    * the form:

    *

    * product_<item id> - the id of the item to be added

    * quantity_<item id> - the quantity to add

    *

    * If no quantity is set, a single item will be added.

    *

    * @param melati - the melati for this request

    *

    * @return - "Trolley" - the page where users manipulate their 

    *           Shopping Trolley

    *

    * @throws InstantiationPropertyException - if we cannot construct trolley

    **/

   protected String MultipleAdd(Melati melati)

    throws InstantiationPropertyException {

     ShoppingTrolley trolley = ShoppingTrolley.getInstance(melati,config);

     for (Enumeration e = melati.getRequest().getParameterNames(); 

                      e.hasMoreElements();) {

       String name = (String)e.nextElement();

       if (name.length() > 8) {

         String p = name.substring(0,7);

         if (p.equals("product")) {

           String id = name.substring(8);

           Integer idInt = new Integer(id);

           ShoppingTrolleyItem item = trolley.getItem(idInt);

           String quantityName = "quantity_" + id;

           String priceName = "price_" + id;

           String descriptionName = "description_" + id;

           Integer quantity = new Integer(1);

           Double price = null;

           String quantitySring = 

                  Form.getFormNulled

                  (melati.getServletTemplateContext(), quantityName);

           String priceString = 

                  Form.getFormNulled

                  (melati.getServletTemplateContext(), priceName);

           String description = 

                  Form.getFormNulled

                  (melati.getServletTemplateContext(), descriptionName);

           if (quantitySring != null) 

             quantity = new Integer(quantitySring);

           if (priceString != null) price = new Double(priceString);

           if (item == null) {

             item = newItem(trolley,idInt,price,description);

           }

           item.setQuantity(new Integer(item.getQuantity().intValue() + quantity.intValue()));

         }

       }

     }

     melati.getTemplateContext().put("trolley",trolley);

     return JammyJoesUtil.shoppingTemplate(melati, "Trolley");

   }

   /** 

    * add a single item to the trolley, or add to the quantity already in the 

    * trolley.  the product is specified on the pathinfo which should be of the

    * form:

    *

    * /<logicaldatabase>/<id>/<quantity>/Add/

    *

    * if no quantity is set, a single item will be added.  The form parmaeters

    * will be parsed to see if they contain "price" and/or "description" fields.

    * if they are present, they will be used to set up the item

    *

    * @param melati - the melati for this request

    * @param id - the id of the item to be added

    *

    * @return - "Trolley" - the page where users manipulate their 

    *           Shopping Trolley

    *

    * @throws InstantiationPropertyException - if we cannot construct trolley

    **/

   protected String Add(Melati melati, Integer id, Integer quantity)

    throws InstantiationPropertyException {

      System.err.println("Adding");

     // the quantity is defaulted to 1, so if you don't set it you will get one

     if (quantity == null || quantity.intValue() == 0) quantity = new Integer(1);

     ShoppingTrolley trolley = ShoppingTrolley.getInstance(melati,config);

     ShoppingTrolleyItem item = trolley.getItem(id);

     if (item == null) {

       Double price = null;

       String priceString = 

              Form.getFormNulled(melati.getServletTemplateContext(), "price");

       if (priceString != null) price = new Double(priceString);

       item = newItem(trolley,id,price,

           Form.getFormNulled(melati.getServletTemplateContext(), "description"));

     }    

     Integer currentQuantity = item.getQuantity();

     if (currentQuantity == null) currentQuantity = new Integer(0);

     item.setQuantity(new Integer(currentQuantity.intValue() + quantity.intValue()));

     melati.getTemplateContext().put("trolley",trolley);

     return JammyJoesUtil.shoppingTemplate(melati, "Trolley");

   }

   /** 

    * remove a single item from the trolley, the product is specified on the 

    * pathinfo which should be of the form:

    *

    * /<logicaldatabase>/<id>/Remove/

    *

    * @param melati - the melati for this request

    *

    * @return - "Trolley" - the page where users manipulate their 

    *           Shopping Trolley

    *

    * @throws InstantiationPropertyException - if we cannot construct trolley

    **/

   protected String Remove(Melati melati, Integer id)

    throws InstantiationPropertyException {

     ShoppingTrolley trolley = ShoppingTrolley.getInstance(melati,config);

     ShoppingTrolleyItem item = trolley.getItem(id);

     trolley.removeItem(item);

     melati.getTemplateContext().put("trolley",trolley);

     return JammyJoesUtil.shoppingTemplate(melati, "Trolley");

   }

   /** 

    * set the quantity of an item in the trolley, 

    * the product and new quantity is

    * specified on the pathinfo which should be of the form:

    *

    * /<logicaldatabase>/<id>/<quantity>/Set/

    *

    * @param melati - the melati for this request

    * @param id - the id of the item to be removed

    *

    * @return - "Trolley" - the page where users manipulate their 

    *           Shopping Trolley

    *

    * @throws InstantiationPropertyException - if we cannot construct trolley

    **/

   protected String Set(Melati melati, Integer id, Integer quantity)

    throws InstantiationPropertyException {

     ShoppingTrolley trolley = ShoppingTrolley.getInstance(melati,config);

     ShoppingTrolleyItem item = trolley.getItem(id);

     if (item == null) item = newItem(trolley,id, null, null);

     item.setQuantity(quantity);

     melati.getTemplateContext().put("trolley",trolley);

     return JammyJoesUtil.shoppingTemplate(melati, "Trolley");

   }

   /** 

    * return the page where the user enters their details

    *

    * @param melati - the melati for this request

    *

    * @return - "Details" - the page where users enter their details

    *

    * @throws InstantiationPropertyException - if we cannot construct trolley

    **/

   protected String Details(Melati melati)

    throws InstantiationPropertyException {

     ShoppingTrolley trolley = ShoppingTrolley.getInstance(melati,config);

     trolley.setDefaultDetails(melati);

     melati.getTemplateContext().put("trolley",trolley);

     return JammyJoesUtil.shoppingTemplate(melati, "Details");

   }

   /** 

    * update the user's information and return the

    * confirmation page

    *

    * @param melati - the melati for this request

    *

    * @return - "Confirm" - the page where users confirm their order

    *

    * @throws InstantiationPropertyException - if we cannot construct trolley

    */

   protected String Confirm(Melati melati)

    throws InstantiationPropertyException {

     JammyJoesShoppingTrolley trolley = (JammyJoesShoppingTrolley)ShoppingTrolley.getInstance(melati,config);

     if (Form.getFormNulled(melati.getServletTemplateContext(),"submittoken") != null) 

       trolley.setFromForm(melati);

     trolley.save();

     melati.getServletTemplateContext().put("trolley",trolley);

     return JammyJoesUtil.shoppingTemplate(melati, "Confirm");

   }

   /** 

    * complete the user's shopping experience, and remove their Shopping Trolley

    * from the Session

    *

    * If you need to do something (like send an email) following confirmation 

    * of payment, define the method in <Your>ShoppingTrolley.java:

    * 

    *  public void confirmPayment(Melati melati) {}

    *

    * Because the callback request (typically) comes from the Payment Server, 

    * you will not have the user's shoping trolley (Session) available to them.

    * You will therefore need to get whatever information you require from 

    * something persistent.

    *

    * The alternative is to get the Payment Server to generate the emails (or 

    * whatever) for you.  Most Payment Servers offer this facility. 

    *

    * @param melati - the melati for this request

    *

    * @return - "Paid" - a message thanking the user for their order

    *

    * @throws InstantiationPropertyException - if we cannot construct trolley

    */

   protected String Paid(Melati melati) 

    throws InstantiationPropertyException {

     ShoppingTrolley trolley = ShoppingTrolley.getInstance(melati,config);

     trolley.confirmPayment(melati);

     // and get rid of it

     trolley.remove(melati);

     return JammyJoesUtil.shoppingTemplate(melati, "Paid");

   }

   /** 

    * abandon a trolley 

    *

    * @param melati - the melati for this request

    *

    * @return - "Trolley" - the initial trolley page

    *

    * @throws InstantiationPropertyException - if we cannot construct trolley

    */

   protected String Abandon(Melati melati) 

    throws InstantiationPropertyException {

     ShoppingTrolley trolley = ShoppingTrolley.getInstance(melati,config);

     // and get rid of it

     trolley.remove(melati);

     return JammyJoesUtil.shoppingTemplate(melati, "Trolley");

   }

   /** 

    * force a user to login

    *

    * @param melati - the melati for this request

    */

   protected void assertLogin(Melati melati) 

    throws InstantiationPropertyException {

     ShoppingTrolley trolley = ShoppingTrolley.getInstance(melati,config);

     // deligate to your trolley

     trolley.assertLogin(melati);

   }

   /** 

    * create a new item and add it to the ShoppingTrolley

    *

    * if a price is passed

    *

    * @param trolley - the trolley to add the item to 

    * @param melati - the melati for this request

    * @param id - the id of the item to be added

    *

    * @return - the new shopping trolley item

    */

   private ShoppingTrolleyItem newItem(ShoppingTrolley trolley, Integer id,

                                       Double price, String description)

    throws InstantiationPropertyException {

     return trolley.newItem(id, description, price);

   }

   /** 

    * override the building of the MelatiContext in order to glean the 

    * additional information required for the Shopping Trolley system

    *

    * @param melati - the melati for this request

    *

    * @return - the ShoppingContext with as many bits set up as possible

    *

    * @throws PathInfoException - if we don't understand the PathInfo

    */

   protected PoemContext poemContext(Melati melati)

       throws PathInfoException {

     ShoppingContext it = new ShoppingContext();

     String[] parts = melati.getPathInfoParts();

     if (parts.length < 2) 

       throw new PathInfoException(

           "The servlet expects to see pathinfo in the form " +

           "/db/method/ or /db/method/troid or /db/method/troid/quantity");

     it.setLogicalDatabase(parts[0]);

     it.setMethod(parts[1]);

     try {

       if (parts.length > 2 && !parts[2].equals("")) 

         it.stid = new Integer(parts[2]);

       if (parts.length > 3 && !parts[3].equals(""))

         it.quantity = new Integer(parts[3]);

     } catch (NumberFormatException e) {

       throw new PathInfoException(

           "The servlet expects to see pathinfo in the form " +

           "/db/method/ or /db/troid/method/ or /db/troid/quantity/method/ " +

           "where the troid is an integer and the quantity is a number");

     }

     return it;

   }

 }