package fi.affecto.osti.fwkint.servlet;

import java.io.IOException;

import javax.inject.Inject;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebFilter;
import javax.transaction.Status;
import javax.transaction.SystemException;
import javax.transaction.UserTransaction;

@WebFilter(value = "/*")
public class RollbackFilter implements Filter
{
	@Inject
	private UserTransaction userTransaction;

	@Override
	public void destroy()
	{
	}

	@Override
	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException
	{
		try
		{
			rollbackTransactionIfActive();
			chain.doFilter(request, response);
		}
		finally
		{
			rollbackTransactionIfActive();
		}
	}

	private void rollbackTransactionIfActive()
	{
		try
		{
			if (userTransaction.getStatus() == Status.STATUS_ACTIVE)
			{
				userTransaction.rollback();
			}
		}
		catch (SystemException e)
		{
			// so not?
		}
	}

	@Override
	public void init(FilterConfig config) throws ServletException
	{
	}

}