package com.nanometer.smartlab.listener;

import org.apache.shiro.SecurityUtils;
import org.apache.shiro.subject.Subject;
import org.primefaces.context.RequestContext;

import javax.faces.FacesException;
import javax.faces.FactoryFinder;
import javax.faces.application.ViewHandler;
import javax.faces.component.UIViewRoot;
import javax.faces.context.ExternalContext;
import javax.faces.context.FacesContext;
import javax.faces.context.ResponseWriter;
import javax.faces.event.PhaseEvent;
import javax.faces.event.PhaseId;
import javax.faces.event.PhaseListener;
import javax.faces.render.RenderKit;
import javax.faces.render.RenderKitFactory;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * Created by johnny on 16/3/14.
 */
public class MyJsfAjaxTimeoutPhaseListener implements PhaseListener {

    @Override
    public void afterPhase(PhaseEvent event) {

    }

    @Override
    public void beforePhase(PhaseEvent event) {
        FacesContext fc = FacesContext.getCurrentInstance();
        RequestContext rc = RequestContext.getCurrentInstance();
        ExternalContext ec = fc.getExternalContext();
        HttpServletResponse response = (HttpServletResponse) ec.getResponse();
        HttpServletRequest request = (HttpServletRequest) ec.getRequest();

        Subject subject = SecurityUtils.getSubject();

        if (!subject.isAuthenticated()) {
            // considered to be a Timeout case
            if (ec.isResponseCommitted()) {
                // redirect is not possible
                return;
            }
            try {
                if (((rc!=null &&  RequestContext.getCurrentInstance().isAjaxRequest())
                        || (fc!=null && fc.getPartialViewContext().isPartialRequest()))
                        && fc.getResponseWriter() == null
                        && fc.getRenderKit() == null) {
                    response.setCharacterEncoding(request.getCharacterEncoding());
                    RenderKitFactory factory = (RenderKitFactory) FactoryFinder.getFactory(FactoryFinder.RENDER_KIT_FACTORY);
                    RenderKit renderKit = factory.getRenderKit(fc, fc.getApplication().getViewHandler().calculateRenderKitId(fc));
                    ResponseWriter responseWriter = renderKit.createResponseWriter(response.getWriter(), null, request.getCharacterEncoding());
                    fc.setResponseWriter(responseWriter);

                    ViewHandler viewHandler = fc.getApplication().getViewHandler();
                    UIViewRoot viewRoot = viewHandler.createView(fc, "/login.xhtml");
                    fc.setViewRoot(viewRoot);
                    fc.renderResponse();
//                    viewHandler.renderView(fc, viewRoot);
//                    fc.responseComplete();

                    ec.redirect(ec.getRequestContextPath() + "/login.xhtml");
                }
            } catch (IOException e) {
                throw new FacesException(e);
            }
        } else {
            return ; //This is not a timeout case . Do nothing !
        }
    }

    @Override
    public PhaseId getPhaseId() {
        return PhaseId.RESTORE_VIEW;
    }
}