/*
 * Copyright (c) 2019 Contributors to the Eclipse Foundation
 *
 * See the NOTICE file(s) distributed with this work for additional
 * information regarding copyright ownership.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * You may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */
package org.eclipse.microprofile.starter.exception;

import javax.faces.FacesException;
import javax.faces.application.FacesMessage;
import javax.faces.application.ViewExpiredException;
import javax.faces.context.ExceptionHandler;
import javax.faces.context.ExceptionHandlerWrapper;
import javax.faces.context.FacesContext;
import javax.faces.event.ExceptionQueuedEvent;
import javax.faces.event.ExceptionQueuedEventContext;
import java.util.Iterator;

public class CustomExceptionHandler extends ExceptionHandlerWrapper {

    private ExceptionHandler wrapped;

    CustomExceptionHandler(ExceptionHandler exception) {
        this.wrapped = exception;
    }

    @Override
    public ExceptionHandler getWrapped() {
        return wrapped;
    }

    @Override
    public void handle() throws FacesException {
        final Iterator<ExceptionQueuedEvent> i = getUnhandledExceptionQueuedEvents().iterator();
        while (i.hasNext()) {
            ExceptionQueuedEvent event = i.next();
            ExceptionQueuedEventContext context = (ExceptionQueuedEventContext) event.getSource();

            // get the exception from context
            Throwable t = context.getException();

            FacesContext facesContext = FacesContext.getCurrentInstance();

            if (t instanceof ViewExpiredException) {
                try {

                    String homeLocation = "/index.xhtml";
                    facesContext.setViewRoot(facesContext.getApplication().getViewHandler().createView(facesContext, homeLocation));
                    facesContext.getPartialViewContext().setRenderAll(true);
                    String messageText = "Your session is expired and data is resetted.";
                    FacesMessage message = new FacesMessage(FacesMessage.SEVERITY_ERROR, messageText, messageText);
                    facesContext.addMessage(null, message);
                    facesContext.renderResponse();

                } finally {
                    //remove it from queue
                    i.remove();
                }
            }
        }
        //parent handle
        getWrapped().handle();
    }
}