/**
 * Copyright 2012 Comcast Corporation
 * 
 * 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 com.comcast.cns.controller;

import java.util.List;

import javax.servlet.AsyncContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.log4j.Logger;

import com.comcast.cmb.common.model.CMBPolicy;
import com.comcast.cmb.common.model.User;
import com.comcast.cmb.common.persistence.PersistenceFactory;
import com.comcast.cns.io.CNSTopicPopulator;
import com.comcast.cns.model.CNSTopic;

/**
 * List topics
 * @author bwolf
 *
 */
public class CNSListTopicsAction extends CNSAction {
	
	private static Logger logger = Logger.getLogger(CNSListTopicsAction.class);

	public CNSListTopicsAction() {
		super("ListTopics");
	}

    /**
     * Get all the topics for this user and output them in XML to the response 
     * @param user The user for which we are getting the list of topics
     * @param asyncContext
     */
	@Override
	public boolean doAction(User user, AsyncContext asyncContext) throws Exception {
		
        HttpServletRequest request = (HttpServletRequest)asyncContext.getRequest();
        HttpServletResponse response = (HttpServletResponse)asyncContext.getResponse();

		String userId = user.getUserId();
		String nextToken = null;
		
		if (request.getParameter("NextToken") != null) {
			nextToken = request.getParameter("NextToken");
			logger.debug("event=cns_topic_list next_token=" + nextToken + " userid=" + userId);
		} else {
			logger.debug("event=cns_topic_list userid=" + userId);
		}
			
		List<CNSTopic> topics = PersistenceFactory.getTopicPersistence().listTopics(userId, nextToken);

		if (topics.size() >= 100) {
			
			nextToken = topics.get(99).getArn();
			List<CNSTopic> nextTopics = PersistenceFactory.getTopicPersistence().listTopics(userId, nextToken);
			
			if (nextTopics.size() == 0) {
				nextToken = null;
			} else {
				logger.debug("event=cns_topic_listed event=next_token_created next_token=" + nextToken + " user_id=" + userId);
			}
		}
		
		String out = CNSTopicPopulator.getListTopicsResponse(topics,nextToken);			
        writeResponse(out, response);
		return true;
	}
	
	@Override
	public boolean isActionAllowed(User user, HttpServletRequest request, String service, CMBPolicy policy) throws Exception {
		return true;
	}
}