/*
 * Copyright 2014 Federal Chancellery Austria
 * MOA-ID has been developed in a cooperation between BRZ, the Federal
 * Chancellery Austria - ICT staff unit, and Graz University of Technology.
 *
 * Licensed under the EUPL, Version 1.1 or - as soon they will be approved by
 * the European Commission - subsequent versions of the EUPL (the "Licence");
 * You may not use this work except in compliance with the Licence.
 * You may obtain a copy of the Licence at:
 * http://www.osor.eu/eupl/
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the Licence is distributed on an "AS IS" basis,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the Licence for the specific language governing permissions and
 * limitations under the Licence.
 *
 * This product combines work with different licenses. See the "NOTICE" text
 * file for details on the various modules and licenses.
 * The "NOTICE" text file is part of the distribution. Any derivative works
 * that you distribute must include a readable copy of the "NOTICE" text file.
 */
package at.gv.egovernment.moa.id.auth.servlet.interceptor;

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

import org.apache.commons.lang3.StringUtils;
import org.apache.commons.text.StringEscapeUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import at.gv.egiz.eaaf.core.api.IRequest;
import at.gv.egiz.eaaf.core.api.IRequestStorage;
import at.gv.egiz.eaaf.core.api.data.EAAFConstants;
import at.gv.egiz.eaaf.core.impl.utils.Random;
import at.gv.egiz.eaaf.core.impl.utils.TransactionIDUtils;
import at.gv.egovernment.moa.id.moduls.SSOManager;
import at.gv.egovernment.moa.util.MiscUtil;
import at.gv.egovernment.moaspss.logging.Logger;

/**
 * @author tlenz
 *
 */
public class UniqueSessionIdentifierInterceptor implements HandlerInterceptor {

	@Autowired private IRequestStorage requestStorage;
	@Autowired(required=false) private SSOManager ssomanager;
	
	
	/* (non-Javadoc)
	 * @see org.springframework.web.servlet.HandlerInterceptor#preHandle(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse, java.lang.Object)
	 */
	@Override
	public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
			throws Exception {
		
		String uniqueSessionIdentifier = null;
		
		Logger.trace("PreProcess req. in " + UniqueSessionIdentifierInterceptor.class.getName());
		
		//if SSOManager is available, search SessionIdentifier in SSO session
		if (ssomanager != null) {
			String ssoId = ssomanager.getSSOSessionID(request);			
			uniqueSessionIdentifier = ssomanager.getUniqueSessionIdentifier(ssoId);
			
		}
		
		// search SessionIdentifier in PendingRequest if available
		if (MiscUtil.isEmpty(uniqueSessionIdentifier)) {
			String pendingReqId = StringEscapeUtils.escapeHtml4(
					request.getParameter(EAAFConstants.PARAM_HTTP_TARGET_PENDINGREQUESTID));			
			if (StringUtils.isNotEmpty(pendingReqId)) {
				IRequest pendingReq = requestStorage.getPendingRequest(pendingReqId);
				if (pendingReq != null)
					uniqueSessionIdentifier = pendingReq.getUniqueSessionIdentifier();
				
			}						
		}
		
		//if NO SSOSession and no PendingRequest create new SessionIdentifier
		if (StringUtils.isEmpty(uniqueSessionIdentifier)) {
			uniqueSessionIdentifier = Random.nextHexRandom16();
			Logger.debug("Set new UniqueSessionIdentifier: " + uniqueSessionIdentifier);
		}
		
		TransactionIDUtils.setSessionId(uniqueSessionIdentifier);		
		request.setAttribute(EAAFConstants.UNIQUESESSIONIDENTIFIER, uniqueSessionIdentifier);		
		return true; 
		
	}

	/* (non-Javadoc)
	 * @see org.springframework.web.servlet.HandlerInterceptor#postHandle(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse, java.lang.Object, org.springframework.web.servlet.ModelAndView)
	 */
	@Override
	public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
			ModelAndView modelAndView) throws Exception {
		
	}

	/* (non-Javadoc)
	 * @see org.springframework.web.servlet.HandlerInterceptor#afterCompletion(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse, java.lang.Object, java.lang.Exception)
	 */
	@Override
	public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
			throws Exception {
		TransactionIDUtils.removeAllLoggingVariables();
		
	}

}