package br.com.ventek.teste;

import java.io.IOException;
import java.util.Date;

import javax.enterprise.context.NonexistentConversationException;
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.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.jboss.weld.Container;
import org.jboss.weld.context.http.HttpConversationContext;

/**
 * Servlet Filter implementation class ConversationFilter
 */
public class ConversationFilter implements Filter {

	/**
	 * Default constructor.
	 */
	public ConversationFilter() {
		// TODO Auto-generated constructor stub
	}

	/**
	 * @see Filter#destroy()
	 */
	public void destroy() {
		// TODO Auto-generated method stub
	}

	protected HttpConversationContext getHttpConversationContext() {
		return Container.instance().deploymentManager().instance()
				.select(HttpConversationContext.class).get();
	}

	protected void doAssociate(HttpServletRequest request) {
		getHttpConversationContext().associate(request);
	}

	protected void doActivate(String conversationId) {
		HttpConversationContext conversationContext = getHttpConversationContext();
		if (conversationId != null && conversationId.isEmpty() == false) {
			conversationContext.activate(conversationId);
		} else {
			conversationContext.activate();
		}
	}

	protected void doInvalidate() {
		getHttpConversationContext().invalidate();
	}

	protected void doDeactivate() {
		getHttpConversationContext().deactivate();
	}

	protected void doDissociate(HttpServletRequest request) {
		getHttpConversationContext().dissociate(request);
	}

	private void process(HttpServletRequest request,
			HttpServletResponse response, FilterChain chain) throws IOException,
			ServletException {
		doAssociate(request);
		String param[] = request.getParameterValues(getHttpConversationContext()
				.getParameterName());
		String conversationId = param != null && param.length != 0 ? param[0]
				: null;
		try {
			doActivate(conversationId);
			boolean isTimedOut = false;
			if (conversationId != null) {
				long time = getHttpConversationContext()
						.getConversation(conversationId).getTimeout();
				Date timeOut = new Date(getHttpConversationContext().getConversation(
						conversationId).getLastUsed()
						+ time);
				isTimedOut = new Date().after(timeOut);
				if (isTimedOut) {
					getHttpConversationContext().getConversation(conversationId).end();
				}
			}
			if (!isTimedOut) {
				chain.doFilter(request, response);
			} else {
				response.sendError(HttpServletResponse.SC_NOT_FOUND,
						"Conversation time out!");
			}
			if (getHttpConversationContext().getCurrentConversation().isTransient()) {
				doDissociate(request);
			}
		} catch (NonexistentConversationException e) {
			response.sendError(HttpServletResponse.SC_NOT_FOUND,
					"Conversation not found!");
		}
	}

	/**
	 * @see Filter#doFilter(ServletRequest, ServletResponse, FilterChain)
	 */
	public void doFilter(ServletRequest request, ServletResponse response,
			FilterChain chain) throws IOException, ServletException {

		if (request instanceof HttpServletRequest
				&& response instanceof HttpServletResponse) {
			process((HttpServletRequest) request, (HttpServletResponse) response,
					chain);
		}

	}

	/**
	 * @see Filter#init(FilterConfig)
	 */
	public void init(FilterConfig fConfig) throws ServletException {
	}

}