text: /*-
   *
   *  This file is part of Oracle NoSQL Database
   *  Copyright (C) 2014, 2018 Oracle and/or its affiliates.  All rights reserved.
   *
   * If you have received this file as part of Oracle NoSQL Database the
   * following applies to the work as a whole:
   *
   *   Oracle NoSQL Database server software is free software: you can
   *   redistribute it and/or modify it under the terms of the GNU Affero
   *   General Public License as published by the Free Software Foundation,
   *   version 3.
   *
   *   Oracle NoSQL Database 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
   *   Affero General Public License for more details.
   *
   * If you have received this file as part of Oracle NoSQL Database Client or
   * distributed separately the following applies:
   *
   *   Oracle NoSQL Database client software is free software: you can
   *   redistribute it and/or modify it under the terms of the Apache License
   *   as published by the Apache Software Foundation, version 2.0.
   *
   * You should have received a copy of the GNU Affero General Public License
   * and/or the Apache License in the LICENSE file along with Oracle NoSQL
   * Database client or server distribution.  If not, see
   * <http://www.gnu.org/licenses/>
   * or
   * <http://www.apache.org/licenses/LICENSE-2.0>.
   *
   * An active Oracle commercial licensing agreement for this product supersedes
   * these licenses and in such case the license notices, but not the copyright
   * notice, may be removed by you in connection with your distribution that is
   * in accordance with the commercial licensing terms.
   *
   * For more information please contact:
   *
   * berkeleydb-info_us@oracle.com
   *
   */
  'use strict'
  
  /*global logConfiguration*/
  /*global fs*/
  
  var CONFIG_FILE = 'nosqldb.logconf.json';
  
  function getTime() {
    var date = new Date();
    var hour = date.getHours();
    hour = (hour < 10 ? '0' : '') + hour;
    var min = date.getMinutes();
    min = (min < 10 ? '0' : '') + min;
    var sec = date.getSeconds();
    sec = (sec < 10 ? '0' : '') + sec;
    var msec = date.getMilliseconds();
    msec = (msec < 10 ? '00' : (msec < 100 ? '0' : '') ) + msec;
    var year = date.getFullYear();
    var month = date.getMonth() + 1;
    month = (month < 10 ? '0' : '') + month;
    var day = date.getDate();
    day = (day < 10 ? '0' : '') + day;
  
    return year + '-' + month + '-' + day + ' ' + hour + ':' + min + ':' + sec +
      '.' + msec;
  }
  
  function setFile(file, callback) {
    if (typeof file === 'string') {
      if (!fs.existsSync(file)) {
        var firstMessage = '[' + getTime() +
          '] [INIT] KVStore for node.js log system - file created\n';
        fs.writeFile(file, firstMessage, function (err) {
          if (err) {
            if (callback) callback(err);
            else throw err;
          } else return file;
        });
      }
      return file;
    }
  }
  
  function verifyDebugLevel(logLevel) {
    var result = 0;
    if (typeof logLevel === 'string')
      result = levels.levels.indexOf(logLevel);
    else if (typeof logLevel === 'number')
      result = logLevel;
  
    return result;
  }
  
  function log(logger, level, stringLevel, message, callback) {
    if (logger.logLevel >= level) {
  
      var stack = new Error().stack.split('\n');
      if (typeof message !== 'string') {
        message = JSON.stringify(message);
      }
      var logString = '[' + getTime() + '] ' +
        stringLevel + '[' + stack[3].trim() + '] ' +
        message + '\n';
      if (logger.logToFile) {
        fs.appendFile(logger.logFile, logString, function (err) {
          if (err) {
            if (callback) callback(err);
            else throw err;
          }
        });
      }
      if (logger.logToConsole)
        console.log(logString);
    }
  }
  
  var levels = {
    OFF: 0,
    FATAL: 1,
    ERROR: 2,
    WARN: 3,
    INFO: 4,
    DEBUG: 5,
    TRACE: 6,
    ALL: 7,
    levels: ['OFF', 'FATAL', 'ERROR', 'WARN', 'INFO', 'DEBUG', 'TRACE', 'ALL']
  }
  exports.LOG_LEVELS = levels;
  
  /**
   * Creates a new Logger object
   * @constructor
   */
  function Logger() {
    var conf = {};
    if (fs.existsSync(CONFIG_FILE)) {
      conf = JSON.parse(fs.readFileSync(CONFIG_FILE));
      if (conf) {
        this.logLevel = conf.logLevel;
        this.logToFile = conf.logToFile;
        this.logFile = conf.logFile;
        this.logToConsole = conf.logToConsole;
        return;
      }
    } else {
      this.logLevel = conf.logLevel = levels.OFF;
      this.logToFile = conf.logToFile = true;
      this.logFile = conf.logFile = 'nosqldb-oraclejs.log';
      this.logToConsole = conf.logToConsole = false;
      fs.writeFileSync(CONFIG_FILE, JSON.stringify(conf, null, 4));
    }
    this.LOG_LEVELS = levels;
  }
  exports.Logger = Logger;
  
  
  Logger.prototype.trace = function (message, callback) {
    log(this, levels.TRACE, '[TRACE] ', message, callback);
  };
  
  Logger.prototype.debug = function (message, callback) {
    log(this, levels.DEBUG, '[DEBUG] ', message, callback);
  };
  
  Logger.prototype.info = function (message, callback) {
    log(this, levels.INFO, '[INFO]  ', message, callback);
  };
  
  Logger.prototype.warn = function (message, callback) {
    log(this, levels.WARN, '[WARN]  ', message, callback);
  };
  
  Logger.prototype.error = function (message, callback) {
    log(this, levels.ERROR, '[ERROR] ', message, callback);
  };
  
  Logger.prototype.fatal = function (message, callback) {
    log(this, levels.FATAL, '[FATAL] ', message, callback);
  };
  