/*
    * This file is part of Waarp Project (named also Waarp or GG).
    *
    *  Copyright (c) 2019, Waarp SAS, and individual contributors by the @author
    *  tags. See the COPYRIGHT.txt in the distribution for a full listing of
    * individual contributors.
    *
    *  All Waarp Project 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.
   *
   * Waarp 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
   * Waarp . If not, see <http://www.gnu.org/licenses/>.
   */
  package org.waarp.common.logging;
  
  import ch.qos.logback.classic.Level;
  import ch.qos.logback.classic.Logger;
  import org.slf4j.LoggerFactory;
  import org.slf4j.helpers.NOPLoggerFactory;
  
  import java.io.OutputStream;
  import java.io.PrintStream;
  import java.io.UnsupportedEncodingException;
  
  /**
   * logger factory using SLF4J from LOGBACK
   */
  public class WaarpSlf4JLoggerFactory extends WaarpLoggerFactory {
    static final String ROOT = org.slf4j.Logger.ROOT_LOGGER_NAME;
  
    // Old versions: "root" and LoggerContext.ROOT_NAME
  
    /**
     * @param level
     */
    public WaarpSlf4JLoggerFactory(final WaarpLogLevel level) {
      super(level);
      seLevelSpecific(currentLevel);
    }
  
    @Override
    protected final void seLevelSpecific(final WaarpLogLevel level) {
      final Logger logger = (Logger) LoggerFactory.getLogger(ROOT);
      switch (level) {
        case TRACE:
          logger.setLevel(Level.TRACE); //NOSONAR
          break;
        case DEBUG:
          logger.setLevel(Level.DEBUG); //NOSONAR
          break;
        case INFO:
          logger.setLevel(Level.INFO); //NOSONAR
          break;
        case ERROR:
          logger.setLevel(Level.ERROR); //NOSONAR
          break;
        case WARN:
          logger.setLevel(Level.WARN); //NOSONAR
          break;
        default:
          logger.setLevel(Level.OFF); //NOSONAR
      }
    }
  
    @Override
    public final WaarpLogger newInstance(final String name) {
      final Logger logger = (Logger) LoggerFactory.getLogger(name);
      return new WaarpSlf4JLogger(logger);
    }
  
    WaarpSlf4JLoggerFactory(final boolean failIfNOP) {
      super(null);
      assert failIfNOP; // Should be always called with true.
  
      // SFL4J writes it error messages to System.err. Capture them so that the user does not see such a message on
      // the console during automatic detection.
      final StringBuilder buf = new StringBuilder();
      final PrintStream err = System.err;//NOSONAR
      try {
        System.setErr(new PrintStream(new OutputStream() {
          @Override
          public final void write(final int b) {
            buf.append((char) b);
          }
        }, true, "US-ASCII"));
      } catch (final UnsupportedEncodingException e) {
        throw new Error(e);
      }
  
      try {
        if (LoggerFactory.getILoggerFactory() instanceof NOPLoggerFactory) {
          throw new NoClassDefFoundError(buf.toString());
        } else {
         err.print(buf);
         err.flush();
       }
     } finally {
       System.setErr(err);
       seLevelSpecific(currentLevel);
     }
   }
 
   @Override
   protected final WaarpLogLevel getLevelSpecific() {
     final Logger logger = (Logger) LoggerFactory.getLogger(ROOT);
     if (logger.isTraceEnabled()) {
       return WaarpLogLevel.TRACE;
     } else if (logger.isDebugEnabled()) {
       return WaarpLogLevel.DEBUG;
     } else if (logger.isInfoEnabled()) {
       return WaarpLogLevel.INFO;
     } else if (logger.isWarnEnabled()) {
       return WaarpLogLevel.WARN;
     } else if (logger.isErrorEnabled()) {
       return WaarpLogLevel.ERROR;
     }
     return WaarpLogLevel.NONE;
   }
 }