/*
    * This file is part of ***  M y C o R e  ***
    * See http://www.mycore.de/ for details.
    *
    * MyCoRe is free software: you can redistribute it and/or modify
    * it under the terms of the GNU General Public License as published by
    * the Free Software Foundation, either version 3 of the License, or
    * (at your option) any later version.
    *
   * MyCoRe is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with MyCoRe.  If not, see <http://www.gnu.org/licenses/>.
   */
  
  package org.mycore.common.events;
  
  import java.io.File;
  import java.io.IOException;
  import java.net.URL;
  import java.security.CodeSource;
  import java.security.ProtectionDomain;
  import java.util.Enumeration;
  import java.util.Set;
  
  import org.apache.logging.log4j.LogManager;
  import org.apache.logging.log4j.Logger;
  import org.mycore.common.MCRClassTools;
  
  import jakarta.servlet.ServletContainerInitializer;
  import jakarta.servlet.ServletContext;
  import jakarta.servlet.ServletException;
  import se.jiderhamn.classloader.leak.prevention.ClassLoaderLeakPreventor;
  import se.jiderhamn.classloader.leak.prevention.ClassLoaderLeakPreventorFactory;
  
  /**
   * @author Thomas Scheffler (yagee)
   */
  public class MCRServletContainerInitializer implements ServletContainerInitializer {
  
      /* (non-Javadoc)
       * @see jakarta.servlet.ServletContainerInitializer#onStartup(java.util.Set, jakarta.servlet.ServletContext)
       */
      @Override
      public void onStartup(final Set<Class<?>> c, final ServletContext ctx) throws ServletException {
          final boolean runClassLoaderLeakPreventor = runClassLoaderLeakPreventor();
          ClassLoaderLeakPreventor leakPreventor = null;
          if (runClassLoaderLeakPreventor) {
              final ClassLoaderLeakPreventorFactory leakPreventorFactory = new ClassLoaderLeakPreventorFactory();
              ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
              leakPreventor = leakPreventorFactory.newLeakPreventor(classLoader);
              leakPreventor.runPreClassLoaderInitiators();
          }
          MCRShutdownHandler shutdownHandler = MCRShutdownHandler.getInstance();
          shutdownHandler.isWebAppRunning = true;
          shutdownHandler.leakPreventor = leakPreventor;
          MCRStartupHandler.startUp(ctx);
          //Make sure logging is configured
          final Logger logger = LogManager.getLogger();
          if (logger.isDebugEnabled()) {
              try {
                  Enumeration<URL> resources = MCRClassTools.getClassLoader().getResources("META-INF/web-fragment.xml");
                  while (resources.hasMoreElements()) {
                      logger.debug("Found: {}", resources.nextElement());
                  }
              } catch (IOException e) {
                  // TODO Auto-generated catch block
                  e.printStackTrace();
              }
              logger.debug("This class is here: {}", getSource(this.getClass()));
          }
      }
  
      private static String getSource(final Class<? extends MCRServletContainerInitializer> clazz) {
          if (clazz == null) {
              return null;
          }
          ProtectionDomain protectionDomain = clazz.getProtectionDomain();
          CodeSource codeSource = protectionDomain.getCodeSource();
          if (codeSource == null) {
              LogManager.getLogger().warn("Cannot get CodeSource.");
              return null;
          }
          URL location = codeSource.getLocation();
          String fileName = location.getFile();
          File sourceFile = new File(fileName);
          return sourceFile.getName();
      }
  
      private boolean runClassLoaderLeakPreventor() {
          //do not run ClassLoaderLeakPreventor by default on JRE 17
          String defaultValue = (Runtime.version().feature() > 11) ? Boolean.FALSE.toString() : Boolean.TRUE.toString();
          final String propValue = System.getProperty("MCR.ClassLoaderLeakPreventor", defaultValue);
          return Boolean.parseBoolean(propValue);
      }
  
 }