/**
    * Logback: the reliable, generic, fast and flexible logging framework.
    * Copyright (C) 1999-2015, QOS.ch. All rights reserved.
    *
    * This program and the accompanying materials are dual-licensed under
    * either the terms of the Eclipse Public License v1.0 as published by
    * the Eclipse Foundation
    *
    *   or (per the licensee's choosing)
   *
   * under the terms of the GNU Lesser General Public License version 2.1
   * as published by the Free Software Foundation.
   */
  package ch.qos.logback.access.tomcat;
  
  import java.io.File;
  import java.io.IOException;
  import java.net.MalformedURLException;
  import java.net.URL;
  import java.util.ArrayList;
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Map;
  import java.util.concurrent.ExecutorService;
  import java.util.concurrent.ScheduledExecutorService;
  import java.util.concurrent.ScheduledFuture;
  import java.util.concurrent.locks.ReentrantLock;
  
  import ch.qos.logback.access.common.AccessConstants;
  import ch.qos.logback.access.common.joran.JoranConfigurator;
  import ch.qos.logback.access.common.spi.AccessEvent;
  import ch.qos.logback.access.common.spi.IAccessEvent;
  import ch.qos.logback.access.common.util.AccessCommonVersionUtil;
  import ch.qos.logback.core.spi.ConfigurationEvent;
  import ch.qos.logback.core.spi.ConfigurationEventListener;
  import ch.qos.logback.core.util.CoreVersionUtil;
  import ch.qos.logback.core.util.VersionUtil;
  import jakarta.servlet.ServletContext;
  import jakarta.servlet.ServletException;
  
  import org.apache.catalina.Lifecycle;
  import org.apache.catalina.LifecycleException;
  import org.apache.catalina.LifecycleListener;
  import org.apache.catalina.LifecycleState;
  import org.apache.catalina.connector.Request;
  import org.apache.catalina.connector.Response;
  import org.apache.catalina.valves.ValveBase;
  
  import ch.qos.logback.core.Appender;
  import ch.qos.logback.core.BasicStatusManager;
  import ch.qos.logback.core.Context;
  import ch.qos.logback.core.CoreConstants;
  import ch.qos.logback.core.LifeCycleManager;
  import ch.qos.logback.core.boolex.EventEvaluator;
  import ch.qos.logback.core.filter.Filter;
  import ch.qos.logback.core.joran.spi.JoranException;
  import ch.qos.logback.core.spi.AppenderAttachable;
  import ch.qos.logback.core.spi.AppenderAttachableImpl;
  import ch.qos.logback.core.spi.FilterAttachable;
  import ch.qos.logback.core.spi.FilterAttachableImpl;
  import ch.qos.logback.core.spi.FilterReply;
  import ch.qos.logback.core.spi.LifeCycle;
  import ch.qos.logback.core.spi.LogbackLock;
  import ch.qos.logback.core.spi.SequenceNumberGenerator;
  import ch.qos.logback.core.status.ErrorStatus;
  import ch.qos.logback.core.status.InfoStatus;
  import ch.qos.logback.core.status.OnConsoleStatusListener;
  import ch.qos.logback.core.status.Status;
  import ch.qos.logback.core.status.StatusManager;
  import ch.qos.logback.core.status.WarnStatus;
  import ch.qos.logback.core.util.ExecutorServiceUtil;
  import ch.qos.logback.core.util.Loader;
  import ch.qos.logback.core.util.OptionHelper;
  import ch.qos.logback.core.util.StatusListenerConfigHelper;
  
  //import org.apache.catalina.Lifecycle;
  
  /**
   * This class is an implementation of tomcat's Valve interface, by extending
   * ValveBase.
   * 
   * <p>
   * For more information on using LogbackValve please refer to the online
   * documentation on
   * <a href="http://logback.qos.ch/access.html#tomcat">logback-access and
   * tomcat</a>.
   * 
   * @author Ceki G&uuml;lc&uuml;
   * @author S&eacute;bastien Pennec
   */
  public class LogbackValve extends ValveBase
          implements Lifecycle, Context, AppenderAttachable<IAccessEvent>, FilterAttachable<IAccessEvent> {
  
      public final static String DEFAULT_FILENAME = "logback-access.xml";
      public final static String DEFAULT_CONFIG_FILE = "conf" + File.separatorChar + DEFAULT_FILENAME;
      final static String CATALINA_BASE_KEY = "catalina.base";
      final static String CATALINA_HOME_KEY = "catalina.home";
  
     private final LifeCycleManager lifeCycleManager = new LifeCycleManager();
 
     private long birthTime = System.currentTimeMillis();
 
     ReentrantLock configurationLock = new ReentrantLock();
 
     final private List<ConfigurationEventListener> configurationEventListenerList = new ArrayList<>();
 
     // Attributes from ContextBase:
     private String name;
     StatusManager sm = new BasicStatusManager();
     // TODO propertyMap should be observable so that we can be notified
     // when it changes so that a new instance of propertyMap can be
     // serialized. For the time being, we ignore this shortcoming.
     Map<String, String> propertyMap = new HashMap<String, String>();
     Map<String, Object> objectMap = new HashMap<String, Object>();
     private FilterAttachableImpl<IAccessEvent> fai = new FilterAttachableImpl<IAccessEvent>();
 
     AppenderAttachableImpl<IAccessEvent> aai = new AppenderAttachableImpl<IAccessEvent>();
     String filenameOption;
     boolean quiet;
     boolean started;
     boolean alreadySetLogbackStatusManager = false;
     private SequenceNumberGenerator sequenceNumberGenerator;
 
     private ScheduledExecutorService scheduledExecutorService;
 
     public LogbackValve() {
         putObject(CoreConstants.EVALUATOR_MAP, new HashMap<String, EventEvaluator<?>>());
     }
 
     public boolean isStarted() {
         return started;
     }
 
     @Override
     public void startInternal() throws LifecycleException {
 
         versionCheck();
 
         scheduledExecutorService = ExecutorServiceUtil.newScheduledExecutorService();
 
         String filename;
 
         if (filenameOption != null) {
             filename = filenameOption;
         } else {
             addInfo("filename property not set. Assuming [" + DEFAULT_CONFIG_FILE + "]");
             filename = DEFAULT_CONFIG_FILE;
         }
 
         // String catalinaBase = OptionHelper.getSystemProperty(CATALINA_BASE_KEY);
         // String catalinaHome = OptionHelper.getSystemProperty(CATALINA_BASE_KEY);
 
         File configFile = searchForConfigFileTomcatProperty(filename, CATALINA_BASE_KEY);
         if (configFile == null) {
             configFile = searchForConfigFileTomcatProperty(filename, CATALINA_HOME_KEY);
         }
 
         URL resourceURL;
         if (configFile != null)
             resourceURL = fileToUrl(configFile);
         else
             resourceURL = searchAsResource(filename);
 
         if (resourceURL != null) {
             configureAsResource(resourceURL);
         } else {
             addWarn("Failed to find valid logback-access configuration file.");
         }
 
         if (!quiet) {
             StatusListenerConfigHelper.addOnConsoleListenerInstance(this, new OnConsoleStatusListener());
         }
 
         started = true;
         setState(LifecycleState.STARTING);
     }
 
     static String LOGBACK_ACCESS_TOMCAT_NAME = "logback-access-tomcat";
     static String LOGBACK_ACCESS_COMMON_NAME = "logback-access-common";
     static String LOGBACK_CORE_NAME = "logback-core";
 
     private void versionCheck() {
         try {
             String coreVersion = CoreVersionUtil.getCoreVersionBySelfDeclaredProperties();
             String accessCommonVersion = AccessCommonVersionUtil.getAccessCommonVersionBySelfDeclaredProperties();
             VersionUtil.checkForVersionEquality(this, this.getClass(), accessCommonVersion, LOGBACK_ACCESS_TOMCAT_NAME, LOGBACK_ACCESS_COMMON_NAME);
             VersionUtil.compareExpectedAndFoundVersion(this, coreVersion, AccessConstants.class, accessCommonVersion, LOGBACK_ACCESS_COMMON_NAME, LOGBACK_CORE_NAME);
         } catch(NoClassDefFoundError e) {
             addWarn("Missing ch.logback.core.util.VersionUtil class on classpath. The version of logback-core is probably earlier than 1.5.25.");
         } catch(NoSuchMethodError e) {
             addWarn(e.getMessage() + ". The version of logback-core is probably earlier than 1.5.26.");
         }
     }
 
     private URL fileToUrl(File configFile) {
         try {
             return configFile.toURI().toURL();
         } catch (MalformedURLException e) {
             throw new IllegalStateException("File to URL conversion failed", e);
         }
     }
 
     private URL searchAsResource(String filename) {
         URL result = Loader.getResource(filename, getClass().getClassLoader());
         if (result != null)
             addInfo("Found [" + filename + "] as a resource.");
         else
             addInfo("Could NOT find [" + filename + "] as a resource.");
         return result;
     }
 
     private File searchForConfigFileTomcatProperty(String filename, String propertyKey) {
         String propertyValue = OptionHelper.getSystemProperty(propertyKey);
         String candidatePath = propertyValue + File.separatorChar + filename;
         if (propertyValue == null) {
             addInfo("System property \"" + propertyKey + "\" is not set. Skipping configuration file search with ${"
                     + propertyKey + "} path prefix.");
             return null;
         }
         File candidateFile = new File(candidatePath);
         if (candidateFile.exists()) {
             addInfo("Found configuration file [" + candidatePath + "] using property \"" + propertyKey + "\"");
             return candidateFile;
         } else {
             addInfo("Could NOT find configuration file [" + candidatePath + "] using property \"" + propertyKey + "\"");
             return null;
         }
     }
 
     public void addStatus(Status status) {
         StatusManager sm = getStatusManager();
         if (sm != null) {
             sm.add(status);
         }
     }
 
     public void addInfo(String msg) {
         addStatus(new InfoStatus(msg, this));
     }
 
     public void addWarn(String msg) {
         addStatus(new WarnStatus(msg, this));
     }
 
     public void addError(String msg, Throwable t) {
         addStatus(new ErrorStatus(msg, this, t));
     }
 
     private void configureAsResource(URL resourceURL) {
         try {
             JoranConfigurator jc = new JoranConfigurator();
             jc.setContext(this);
             jc.doConfigure(resourceURL);
             addInfo("Done configuring");
         } catch (JoranException e) {
             addError("Failed to configure LogbackValve", e);
         }
     }
 
     public String getFilename() {
         return filenameOption;
     }
 
     public void setFilename(String filename) {
         this.filenameOption = filename;
     }
 
     public boolean isQuiet() {
         return quiet;
     }
 
     public void setQuiet(boolean quiet) {
         this.quiet = quiet;
     }
 
     @Override
     public void invoke(Request request, Response response) throws IOException, ServletException {
         try {
             if (!alreadySetLogbackStatusManager) {
                 alreadySetLogbackStatusManager = true;
                 org.apache.catalina.Context tomcatContext = request.getContext();
                 if (tomcatContext != null) {
                     ServletContext sc = tomcatContext.getServletContext();
                     if (sc != null) {
                         sc.setAttribute(AccessConstants.LOGBACK_STATUS_MANAGER_KEY, getStatusManager());
                     }
                 }
             }
 
             getNext().invoke(request, response);
 
             TomcatServerAdapter adapter = new TomcatServerAdapter(request, response);
             IAccessEvent accessEvent = new AccessEvent(this, request, response, adapter);
 
             addThreadName(accessEvent);
 
             if (getFilterChainDecision(accessEvent) == FilterReply.DENY) {
                 return;
             }
 
             // TODO better exception handling
             aai.appendLoopOnAppenders(accessEvent);
         } finally {
             request.removeAttribute(AccessConstants.LOGBACK_STATUS_MANAGER_KEY);
         }
     }
 
     private void addThreadName(IAccessEvent accessEvent) {
         try {
             final String threadName = Thread.currentThread().getName();
             if (threadName != null) {
                 accessEvent.setThreadName(threadName);
             }
         } catch (Exception ignored) {
         }
     }
 
     @Override
     protected void stopInternal() throws LifecycleException {
         started = false;
         setState(LifecycleState.STOPPING);
         lifeCycleManager.reset();
         if (scheduledExecutorService != null) {
             ExecutorServiceUtil.shutdown(scheduledExecutorService);
             scheduledExecutorService = null;
         }
     }
 
     @Override
     public void addAppender(Appender<IAccessEvent> newAppender) {
         aai.addAppender(newAppender);
     }
 
     @Override
     public Iterator<Appender<IAccessEvent>> iteratorForAppenders() {
         return aai.iteratorForAppenders();
     }
 
     @Override
     public Appender<IAccessEvent> getAppender(String name) {
         return aai.getAppender(name);
     }
 
     @Override
     public boolean isAttached(Appender<IAccessEvent> appender) {
         return aai.isAttached(appender);
     }
 
     @Override
     public void detachAndStopAllAppenders() {
         aai.detachAndStopAllAppenders();
 
     }
 
     @Override
     public boolean detachAppender(Appender<IAccessEvent> appender) {
         return aai.detachAppender(appender);
     }
 
     @Override
     public boolean detachAppender(String name) {
         return aai.detachAppender(name);
     }
 
     public String getInfo() {
         return "Logback's implementation of ValveBase";
     }
 
     // Methods from ContextBase:
     @Override
     public StatusManager getStatusManager() {
         return sm;
     }
 
     public Map<String, String> getPropertyMap() {
         return propertyMap;
     }
 
     @Override
     public void addSubstitutionProperty(String key, String value) {
         this.propertyMap.put(key, value);
     }
 
     @Override
     public void putProperty(String key, String val) {
         this.propertyMap.put(key, val);
     }
 
     @Override
     public String getProperty(String key) {
         return (String) this.propertyMap.get(key);
     }
 
     @Override
     public Map<String, String> getCopyOfPropertyMap() {
         return new HashMap<String, String>(this.propertyMap);
     }
 
     @Override
     public Object getObject(String key) {
         return objectMap.get(key);
     }
 
     @Override
     public void putObject(String key, Object value) {
         objectMap.put(key, value);
     }
 
     @Override
     public void addFilter(Filter<IAccessEvent> newFilter) {
         fai.addFilter(newFilter);
     }
 
     @Override
     public void clearAllFilters() {
         fai.clearAllFilters();
     }
 
     @Override
     public List<Filter<IAccessEvent>> getCopyOfAttachedFiltersList() {
         return fai.getCopyOfAttachedFiltersList();
     }
 
     @Override
     public FilterReply getFilterChainDecision(IAccessEvent event) {
         return fai.getFilterChainDecision(event);
     }
 
     @Override
     public ExecutorService getExecutorService() {
         return getScheduledExecutorService();
     }
 
     @Override
     public String getName() {
         return name;
     }
 
     @Override
     public void setName(String name) {
         if (this.name != null) {
             throw new IllegalStateException("LogbackValve has been already given a name");
         }
         this.name = name;
     }
 
     @Override
     public long getBirthTime() {
         return birthTime;
     }
 
     @Override
     public ReentrantLock getConfigurationLock() {
         return configurationLock;
     }
 
     @Override
     public void register(LifeCycle component) {
         lifeCycleManager.register(component);
     }
 
     // ====== Methods from catalina Lifecycle =====
 
     @Override
     public void addLifecycleListener(LifecycleListener arg0) {
         // dummy NOP implementation
     }
 
     @Override
     public LifecycleListener[] findLifecycleListeners() {
         return new LifecycleListener[0];
     }
 
     @Override
     public void removeLifecycleListener(LifecycleListener arg0) {
         // dummy NOP implementation
     }
 
     @Override
     public String toString() {
         StringBuilder sb = new StringBuilder(this.getClass().getName());
         sb.append('[');
         sb.append(getName());
         sb.append(']');
         return sb.toString();
     }
 
     @Override
     public ScheduledExecutorService getScheduledExecutorService() {
         return scheduledExecutorService;
     }
 
     @Override
     public void addScheduledFuture(ScheduledFuture<?> scheduledFuture) {
         throw new UnsupportedOperationException();
     }
 
     public SequenceNumberGenerator getSequenceNumberGenerator() {
         return sequenceNumberGenerator;
     }
 
     public void setSequenceNumberGenerator(SequenceNumberGenerator sequenceNumberGenerator) {
         this.sequenceNumberGenerator = sequenceNumberGenerator;
     }
 
 
     @Override
     public void addConfigurationEventListener(ConfigurationEventListener listener) {
         configurationEventListenerList.add(listener);
     }
 
     @Override
     public void fireConfigurationEvent(ConfigurationEvent configurationEvent) {
         configurationEventListenerList.forEach( l -> l.listen(configurationEvent));
     }
 }