/*******************************************************************************
 * 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;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.List;

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

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

import at.gv.egovernment.moa.id.commons.api.AuthConfiguration;
import at.gv.egovernment.moa.id.commons.api.exceptions.ConfigurationException;
import at.gv.egovernment.moa.id.monitoring.TestManager;
import at.gv.egovernment.moa.logging.Logger;
import at.gv.egovernment.moa.util.MiscUtil;

@Controller
public class MonitoringServlet {

	private static final String REQUEST_ATTR_MODULE = "module";
	
	@Autowired private AuthConfiguration authConfig;
	
	  public MonitoringServlet() {
		super();
		Logger.debug("Registering servlet " + getClass().getName() + " with mapping '/MonitoringServlet'.");
	}

	@RequestMapping(value = "/MonitoringServlet", method = RequestMethod.GET)
	public void getStatusInformation(HttpServletRequest req, HttpServletResponse resp)
			    throws ServletException, IOException {
		  
		  try {			
			if (authConfig.isMonitoringActive()) {
				Logger.debug("Monitoring Servlet received request");

				TestManager tests = TestManager.getInstance();
				
				String modulename = req.getParameter(REQUEST_ATTR_MODULE);
				if (MiscUtil.isEmpty(modulename)) {
				
					List<String> error = tests.executeTests();
					if (error != null && error.size() > 0) {
						createErrorMessage(req, resp, error);
						
					} else {
						resp.setStatus(HttpServletResponse.SC_OK);
						resp.setContentType("text/html;charset=UTF-8");
						resp.getWriter().write(getHtml(authConfig.getMonitoringMessageSuccess()));
						Logger.info("Monitoring Servlet finished without errors");
					}
					
				} else {
					if (tests.existsModule(modulename)) {
						List<String> errors = tests.executeTest(modulename);
						if (errors != null && errors.size() > 0) {
							createErrorMessage(req, resp, errors);
							
						} else {
							resp.setStatus(HttpServletResponse.SC_OK);
							resp.setContentType("text/html;charset=UTF-8");
							resp.getWriter().write(getHtml(authConfig.getMonitoringMessageSuccess()));
							Logger.info("Monitoring Servlet finished without errors");
						}
						
					} else {
						Logger.warn("NO Testmodule exists with modulename " + modulename);
						resp.setStatus(HttpServletResponse.SC_NOT_FOUND);
						resp.setContentType("text/html;charset=UTF-8");
						PrintWriter out;
						try {
							out = new PrintWriter(resp.getOutputStream());
							out.write("NO Testmodule exists with modulename " + modulename);
							out.flush();
							    
						} catch (IOException e) {
							Logger.warn("Internal Monitoring Servlet Error. ", e);
						} 
					}
					
				}	
			}
			  
		} catch (ConfigurationException e) {
			createErrorMessage(req, resp, Arrays.asList(e.getMessage()));
		}
	  }
	  
	  private void createErrorMessage(HttpServletRequest req, HttpServletResponse resp, List<String> errorMessage) {
		  Logger.warn("Monitoring Servlet found some Error: " + errorMessage);
		  resp.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
		  resp.setContentType("text/html;charset=UTF-8");
		  PrintWriter out;
		  try {
			  out = new PrintWriter(resp.getOutputStream());
			  for (String error : errorMessage)
				  out.write(error + "<br>");
			  out.flush();
			  
		  } catch (IOException e) {
			  Logger.warn("Internal Monitoring Servlet Error. ", e);
		  } 
	  }
	  
	private String getHtml(String text) {
		return "<html><head><title>Reponse</title></head><body>" + text +"</body></html>";
	}
}