package ch.qos.logback.classic.spi;
   
   import org.slf4j.ILoggerFactory;
   import org.slf4j.IMarkerFactory;
   import org.slf4j.helpers.BasicMarkerFactory;
   import org.slf4j.helpers.Util;
   import org.slf4j.spi.MDCAdapter;
   import org.slf4j.spi.SLF4JServiceProvider;
   
  import ch.qos.logback.classic.LoggerContext;
  import ch.qos.logback.classic.util.ContextInitializer;
  import ch.qos.logback.classic.util.LogbackMDCAdapter;
  import ch.qos.logback.core.CoreConstants;
  import ch.qos.logback.core.joran.spi.JoranException;
  import ch.qos.logback.core.status.StatusUtil;
  import ch.qos.logback.core.util.StatusPrinter;
  
  public class LogbackServiceProvider implements SLF4JServiceProvider {
  
      final static String NULL_CS_URL = CoreConstants.CODES_URL + "#null_CS";
  
      /**
       * Declare the version of the SLF4J API this implementation is compiled against.
       * The value of this field is modified with each major release.
       */
      // to avoid constant folding by the compiler, this field must *not* be final
      public static String REQUESTED_API_VERSION = "2.0.99"; // !final
  
      private LoggerContext defaultLoggerContext;
      private IMarkerFactory markerFactory;
      private LogbackMDCAdapter mdcAdapter;
      // private final ContextSelectorStaticBinder contextSelectorBinder =
      // ContextSelectorStaticBinder.getSingleton();
  //    private static Object KEY = new Object();
  //    private volatile boolean initialized = false;
  
      @Override
      public void initialize() {
          defaultLoggerContext = new LoggerContext();
          defaultLoggerContext.setName(CoreConstants.DEFAULT_CONTEXT_NAME);
          initializeLoggerContext();
          defaultLoggerContext.start();
          markerFactory = new BasicMarkerFactory();
          mdcAdapter = new LogbackMDCAdapter();
          // set the MDCAdapter for the defaultLoggerContext immediately
          defaultLoggerContext.setMDCAdapter(mdcAdapter);
      }
  
      private void initializeLoggerContext() {
          try {
              try {
                  new ContextInitializer(defaultLoggerContext).autoConfig();
              } catch (JoranException je) {
                  Util.report("Failed to auto configure default logger context", je);
              }
              // LOGBACK-292
              if (!StatusUtil.contextHasStatusListener(defaultLoggerContext)) {
                  StatusPrinter.printInCaseOfErrorsOrWarnings(defaultLoggerContext);
              }
              // contextSelectorBinder.init(defaultLoggerContext, KEY);
  
          } catch (Exception t) { // see LOGBACK-1159
              Util.report("Failed to instantiate [" + LoggerContext.class.getName() + "]", t);
          }
      }
  
      @Override
  
      public ILoggerFactory getLoggerFactory() {
          return defaultLoggerContext;
  
  //        if (!initialized) {
  //            return defaultLoggerContext;
  //        
  //
  //        if (contextSelectorBinder.getContextSelector() == null) {
  //            throw new IllegalStateException("contextSelector cannot be null. See also " + NULL_CS_URL);
  //        }
  //        return contextSelectorBinder.getContextSelector().getLoggerContext();
      }
  
      @Override
      public IMarkerFactory getMarkerFactory() {
          return markerFactory;
      }
  
      @Override
      public MDCAdapter getMDCAdapter() {
          return mdcAdapter;
      }
  
      @Override
      public String getRequestedApiVersion() {
          return REQUESTED_API_VERSION;
      }
  
  }