package examples.entity.intro;

import javax.ejb.Remote;
import javax.ejb.Stateful;
import javax.ejb.TransactionAttribute;
import javax.ejb.TransactionAttributeType;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.PersistenceContext;
import javax.persistence.PersistenceContextType;
import javax.persistence.PersistenceUnit;

/**
 * Stateful session bean facade for account entities, remotely accessible
 */

@Stateful
@Remote(AccountInterface.class)
public class AccountBean implements AccountInterface { 
    
    /** The entity manager, injected by the container */
    @PersistenceContext(type=PersistenceContextType.EXTENDED, unitName="intro")    
    private EntityManager manager;
    
    @PersistenceUnit(unitName="intro")
    EntityManagerFactory emf;    
    
    private Account account = null;
    
    public void open(int accountNumber) {
        account = manager.find(Account.class, accountNumber);
        if (account == null) {
            account = new Account();
            account.ownerName = "anonymous";
            account.accountNumber = accountNumber;
            manager.persist(account);
        }
    }    
    
	public int getBalance() {
        if(account==null)
            throw new IllegalStateException();
        return account.balance;
    }
        
    @TransactionAttribute(TransactionAttributeType.REQUIRES_NEW)
    public void deposit(int amount) {
        if(account==null)
            throw new IllegalStateException();
        //manager = emf.createEntityManager(PersistenceContextType.EXTENDED);
        //account = manager.merge(account);
        account.deposit(amount);
        manager.flush();
    }

    public int withdraw(int amount) {        
        if(account==null)
            throw new IllegalStateException();
        // manager.lock(account, LockMode.WRITE);
        return account.withdraw(amount);
    }
   

    
}