/*
* ====================================================================
*
* TORPEDO
* A Testbed of Object Relational Products for Enterprise Distributed Objects
* Copyright (c) 2004 The Middleware Company All Rights Reserved
* @author Bruce Martin
* @version 8.25.04
*
* ====================================================================
*/

package com.middleware_company.torpedo.auction.jdo;

import javax.jdo.*;
import javax.rmi.PortableRemoteObject;
import javax.naming.NamingException;
import javax.naming.Context;
import javax.naming.InitialContext;
import java.util.Collection;
import java.util.Iterator;
import java.util.ArrayList;
import com.middleware_company.torpedo.auction.Auction;
import com.middleware_company.torpedo.auction.User;
import com.middleware_company.torpedo.auction.Bid;

public class Persistence extends com.middleware_company.torpedo.auction.Persistence {
    private static Context _context=null;

    public Bid createBid(
            String ID,
            Auction auction,
            User buyer, Float amount, Float maxAmount) throws NamingException {
        PersistenceManager pm = getPersistenceManager();
        Bid newBid = new JDOBid(ID,auction,buyer,amount,maxAmount);
        pm.makePersistent(newBid);
        return newBid;
    }
    public Auction getAuction(String auctionID) throws NamingException {
        PersistenceManager pm = getPersistenceManager();
        Object oid = pm.newObjectIdInstance(JDOAuction.class,auctionID);
        Object o = pm.getObjectById(oid,true);
        return (Auction) o;
    }
    public User getUser(String ID) throws NamingException {
        PersistenceManager pm = getPersistenceManager();
        Object o = pm.getObjectById(pm.newObjectIdInstance(JDOUser.class,ID),false);
        return (User) o;
    }
    public Collection findAllAuctions() throws NamingException {
        PersistenceManager pm = getPersistenceManager();
        Query q = pm.newQuery (JDOAuction.class);
        Collection auctions = (Collection) q.execute();
        return auctions;
    }
    public Collection findHighBids(String auctionID) throws NamingException {
        // JDO QL does not support aggregate functions.
        // So we must do this in Java code, may be inefficient.
        Auction theAuction = getAuction(auctionID);
        Collection allBids = theAuction.getBids();
        Collection highBids = new ArrayList();
        Iterator i = allBids.iterator();
        float highAmount = 0;
        while (i.hasNext()) {
            float bidAmount = ((Bid)i.next()).getAmount().floatValue();
            if (bidAmount > highAmount) highAmount = bidAmount;
        }
        // Have high amount -- now add any bids that match to collection
        i = allBids.iterator();
        while (i.hasNext()) {
            Bid nextBid = (Bid)i.next();
            float bidAmount = nextBid.getAmount().floatValue();
            if (bidAmount == highAmount) highBids.add(nextBid);
        }
        return highBids;
    }
    private static PersistenceManager getPersistenceManager () throws NamingException {
            return getPersistenceManagerFactory ().getPersistenceManager ();
    }

    protected static PersistenceManagerFactory getPersistenceManagerFactory () throws NamingException {
        return (PersistenceManagerFactory) PortableRemoteObject.narrow (getContext ().lookup ("kodo"),
                PersistenceManagerFactory.class);
    }

    private static Context getContext () throws NamingException {
        if (_context == null)
            _context = new InitialContext ();
        return _context;
    }
}