/*-
 * ============LICENSE_START=======================================================
 * SDC
 * ================================================================================
 * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
 * ================================================================================
 * 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.
 * ============LICENSE_END=========================================================
 */

package org.openecomp.sdc.be.monitoring;

import java.net.URI;

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

import org.eclipse.jetty.client.api.Request;
import org.eclipse.jetty.client.api.Response;
import org.eclipse.jetty.proxy.ProxyServlet;
import org.openecomp.sdc.be.components.impl.MonitoringBusinessLogic;
import org.openecomp.sdc.be.impl.WebAppContextWrapper;
import org.openecomp.sdc.common.api.Constants;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.context.WebApplicationContext;

public class EsGateway extends ProxyServlet {

	private static final long serialVersionUID = 1L;
	private static Logger log = LoggerFactory.getLogger(EsGateway.class.getName());

	@Override
	public URI rewriteURI(HttpServletRequest request) {

		String originalUrl = request.getRequestURI();

		String redirectedUrl = getModifiedUrl(request);

		log.debug("EsGateway Redirecting request from: {} , to: {}", originalUrl, redirectedUrl);
		return URI.create(redirectedUrl);
	}

	@Override
	public void customizeProxyRequest(Request proxyRequest, HttpServletRequest request) {
		super.customizeProxyRequest(proxyRequest, request);

	}

	@Override
	protected void onResponseSuccess(HttpServletRequest request, HttpServletResponse response, Response proxyResponse) {
		super.onResponseSuccess(request, response, proxyResponse);
	}

	public String getModifiedUrl(HttpServletRequest request) {
		String esHost = null;
		String esPort = null;
		MonitoringBusinessLogic monitoringBL = getMonitoringBL(request.getSession().getServletContext());
		if (monitoringBL == null) {
			log.error("failed to retrive monitoringBL.");
		} else {
			esHost = monitoringBL.getEsHost();
			esPort = monitoringBL.getEsPort();
		}

		String scheme = request.getScheme();
		String contextPath = request.getContextPath(); // /mywebapp
		String servletPath = request.getServletPath(); // /servlet/MyServlet
		String pathInfo = request.getPathInfo(); // /a/b;c=123
		String queryString = request.getQueryString(); // d=789

		StringBuilder url = new StringBuilder();
		url.append(scheme).append("://").append(esHost);
		url.append(":").append(esPort);
		url.append(contextPath).append(servletPath);

		if (pathInfo != null) {
			url.append(pathInfo);
		}
		if (queryString != null) {
			url.append("?").append(queryString);
		}

		String redirectedUrl = url.toString().replace("/sdc2/esGateway/", "/");
		return redirectedUrl;

	}

	protected MonitoringBusinessLogic getMonitoringBL(ServletContext context) {

		WebAppContextWrapper webApplicationContextWrapper = (WebAppContextWrapper) context.getAttribute(Constants.WEB_APPLICATION_CONTEXT_WRAPPER_ATTR);
		WebApplicationContext webApplicationContext = webApplicationContextWrapper.getWebAppContext(context);
		MonitoringBusinessLogic monitoringBusinessLogic = webApplicationContext.getBean(MonitoringBusinessLogic.class);

		return monitoringBusinessLogic;
	}

}