/**
 * Copyright 2013 the PM2 project authors. All rights reserved.
 * Use of this source code is governed by a license that
 * can be found in the LICENSE file.
 */

var commander   = require('commander');
var fs          = require('fs');
var path        = require('path');
var async       = require('async');
var debug       = require('debug')('pm2:cli');
var util        = require('util');
var chalk       = require('chalk');
var fclone      = require('fclone');

var conf         = require('../constants.js');
var Client      = require('./Client');
var Common      = require('./Common');
var KMDaemon    = require('./Interactor/InteractorDaemonizer');
var Config      = require('./tools/Config');
var Modularizer = require('./API/Modules/Modularizer.js');
var path_structure = require('../paths.js');
var UX          = require('./API/CliUx');

var IMMUTABLE_MSG = chalk.bold.blue('Use --update-env to update environment variables');

/**
 * Main Function to be imported
 * can be aliased to PM2
 *
 * To use it when PM2 is installed as a module:
 *
 * var PM2 = require('pm2');
 *
 * var pm2 = PM2(<opts>);
 *
 *
 * @param {Object}  opts
 * @param {String}  [opts.cwd=<current>]         override pm2 cwd for starting scripts
 * @param {String}  [opts.pm2_home=[<paths.js>]] pm2 directory for log, pids, socket files
 * @param {Boolean} [opts.independent=false]     unique PM2 instance (random pm2_home)
 * @param {Boolean} [opts.daemon_mode=true]      should be called in the same process or not
 * @param {String}  [opts.public_key=null]       keymetrics bucket public key
 * @param {String}  [opts.secret_key=null]       keymetrics bucket secret key
 * @param {String}  [opts.machine_name=null]     keymetrics instance name
 */
var API = module.exports = function(opts) {
  if (!opts) opts = {};
  var that = this;

  this.daemon_mode = typeof(opts.daemon_mode) == 'undefined' ? true : opts.daemon_mode;
  this.pm2_home    = conf.PM2_ROOT_PATH;
  this.public_key   = process.env.KEYMETRICS_SECRET || opts.public_key || null;
  this.secret_key   = process.env.KEYMETRICS_PUBLIC || opts.secret_key || null;
  this.machine_name = process.env.INSTANCE_NAME || opts.machine_name || null

  /**
   * CWD resolution
   */
  this.cwd         = process.cwd();
  if (opts.cwd) {
    this.cwd = path.resolve(opts.cwd);
  }

  /**
   * PM2 HOME resolution
   */
  if (opts.pm2_home && opts.independent == true)
    throw new Error('You cannot set a pm2_home and independent instance in same time');

  if (opts.pm2_home) {
    // Override default conf file
    this.pm2_home        = opts.pm2_home;
    conf = util._extend(conf, path_structure(this.pm2_home));
  }
  else if (opts.independent == true && conf.IS_WINDOWS === false) {
    // Create an unique pm2 instance
    var crypto = require('crypto');
    var random_file = crypto.randomBytes(8).toString('hex');
    this.pm2_home = path.join('/tmp', random_file);

    // If we dont explicitly tell to have a daemon
    // It will go as in proc
    if (typeof(opts.daemon_mode) == 'undefined')
      this.daemon_mode = false;
    conf = util._extend(conf, path_structure(this.pm2_home));
  }

  this._conf = conf;

  if (conf.IS_WINDOWS) {
    // Weird fix, may need to be dropped
    // @todo windows connoisseur double check
    if (process.stdout._handle && process.stdout._handle.setBlocking)
      process.stdout._handle.setBlocking(true);
  }

  this.Client = new Client({
    pm2_home : that.pm2_home,
    conf     : this._conf,
    secret_key : this.secret_key,
    public_key : this.public_key,
    daemon_mode : this.daemon_mode,
    machine_name : this.machine_name
  });

  this.gl_interact_infos = null;
  this.gl_is_km_linked = false;

  try {
    var pid = fs.readFileSync(conf.INTERACTOR_PID_PATH);
    pid = parseInt(pid.toString().trim());
    process.kill(pid, 0);
    that.gl_is_km_linked = true;
  } catch(e) {
    that.gl_is_km_linked = false;
  }

  // For testing purposes
  if (this.secret_key && process.env.NODE_ENV == 'local_test')
    that.gl_is_km_linked = true;

  KMDaemon.getInteractInfo(this._conf, function(i_err, interact) {
    that.gl_interact_infos = interact;
  });
};

/**
 * Connect to PM2
 * Calling this command is now optional
 *
 * @param {Function} cb callback once pm2 is ready for commands
 */
API.prototype.connect = function(noDaemon, cb) {
  var that = this;
  this.start_timer = new Date();

  if (typeof(cb) == 'undefined') {
    cb = noDaemon;
    noDaemon = false;
  } else if (noDaemon === true) {
    // Backward compatibility with PM2 1.x
    this.Client.daemon_mode = false;
    this.daemon_mode = false;
  }

  this.Client.start(function(err, meta) {
    if (err)
      return cb(err);

    if (meta.new_pm2_instance == false && that.daemon_mode === true)
      return cb(err, meta);

    // If new pm2 instance has been popped
    // Lauch all modules
    Modularizer.launchAll(that, function(err_mod) {
      return cb(err, meta);
    });
  });
}

/**
 * Usefull when custom PM2 created with independent flag set to true
 * This will cleanup the newly created instance
 * by removing folder, killing PM2 and so on
 *
 * @param {Function} cb callback once cleanup is successfull
 */
API.prototype.destroy = function(cb) {
  var exec = require('shelljs').exec;
  var that = this;

  debug('Killing and deleting current deamon');

  this.killDaemon(function() {
    var cmd = 'rm -rf ' + that.pm2_home;
    var test_path = path.join(that.pm2_home, 'module_conf.json');
    var test_path_2 = path.join(that.pm2_home, 'pm2.pid');

    if (that.pm2_home.indexOf('.pm2') > -1)
      return cb(new Error('Destroy is not a allowed method on .pm2'));

    if (fs.accessSync) {
      fs.access(test_path, fs.R_OK, function(err) {
        if (err) return cb(err);
        debug('Deleting temporary folder %s', that.pm2_home);
        exec(cmd, cb);
      });
      return false;
    }

    // Support for Node 0.10
    fs.exists(test_path, function(exist) {
      if (exist) {
        debug('Deleting temporary folder %s', that.pm2_home);
        exec(cmd, cb);
      }
      return cb(null);
    });
  });
};

/**
 * Disconnect from PM2 instance
 * This will allow your software to exit by itself
 *
 * @param {Function} [cb] optional callback once connection closed
 */
API.prototype.disconnect = API.prototype.close = function(cb) {
  var that = this;

  if (!cb) cb = function() {};

  this.Client.close(function(err, data) {
    debug('The session lasted %ds', (new Date() - that.start_timer) / 1000);
    return cb(err, data);
  });
};

/**
 * Launch modules
 *
 * @param {Function} cb callback once pm2 has launched modules
 */
API.prototype.launchModules = function(cb) {
  Modularizer.launchAll(this, cb);
};

/**
 * Enable bus allowing to retrieve various process event
 * like logs, restarts, reloads
 *
 * @param {Function} cb callback called with 1st param err and 2nb param the bus
 */
API.prototype.launchBus = function(cb) {
  this.Client.launchBus(cb);
};

/**
 * Exit methods for API
 * @param {Integer} code exit code for terminal
 */
API.prototype.exitCli = function(code) {
  var that = this;

  // Do nothing if PM2 called programmatically (also in speedlist)
  if (conf.PM2_PROGRAMMATIC && process.env.PM2_USAGE != 'CLI') return false;

  KMDaemon.disconnectRPC(function() {
    that.Client.close(function() {
      code = code || 0;
      // Safe exits process after all streams are drained.
      // file descriptor flag.
      var fds = 0;
      // exits process when stdout (1) and sdterr(2) are both drained.
      function tryToExit() {
        if ((fds & 1) && (fds & 2)) {
          debug('This command took %ds to execute', (new Date() - that.start_timer) / 1000);
          process.exit(code);
        }
      }

      [process.stdout, process.stderr].forEach(function(std) {
        var fd = std.fd;
        if (!std.bufferSize) {
          // bufferSize equals 0 means current stream is drained.
          fds = fds | fd;
        } else {
          // Appends nothing to the std queue, but will trigger `tryToExit` event on `drain`.
          std.write && std.write('', function() {
            fds = fds | fd;
            tryToExit();
          });
        }
        // Does not write anything more.
        delete std.write;
      });
      tryToExit();
    });
  });
};

//////////////////////////
// Load all API methods //
//////////////////////////

require('./API/Deploy.js')(API);
require('./API/Modules/Modules.js')(API);
require('./API/Keymetrics/cli-api.js')(API);
require('./API/Configuration.js')(API);
require('./API/Extra.js')(API);
require('./API/Version.js')(API);
require('./API/Startup.js')(API);
require('./API/LogManagement.js')(API);
require('./API/Interaction.js')(API);
require('./API/Containerizer.js')(API);

////////////////////////////
// Application management //
////////////////////////////

/**
 * Start a file or json with configuration
 * @param {Object||String} cmd script to start or json
 * @param {Function} cb called when application has been started
 */
API.prototype.start = function(cmd, opts, cb) {
  if (typeof(opts) == "function") {
    cb = opts;
    opts = {};
  }
  if (!opts)
    opts = {};

  var that = this;

  if (util.isArray(opts.watch) && opts.watch.length === 0)
    opts.watch = (opts.rawArgs ? !!~opts.rawArgs.indexOf('--watch') : !!~process.argv.indexOf('--watch')) || false;

  if (Common.isConfigFile(cmd) || (typeof(cmd) === 'object'))
    that._startJson(cmd, opts, 'restartProcessId', cb);
  else {
    that._startScript(cmd, opts, cb);
  }
};

/**
 * Reset process counters
 *
 * @method resetMetaProcess
 */
API.prototype.reset = function(process_name, cb) {
  var that = this;

  function processIds(ids, cb) {
    async.eachLimit(ids, conf.CONCURRENT_ACTIONS, function(id, next) {
      that.Client.executeRemote('resetMetaProcessId', id, function(err, res) {
        if (err) console.error(err);
        Common.printOut(conf.PREFIX_MSG + 'Resetting meta for process id %d', id);
        return next();
      });
    }, function(err) {
      if (err) return cb(Common.retErr(err));
      return cb ? cb(null, {success:true}) : that.speedList();
    });
  }

  if (process_name == 'all') {
    that.Client.getAllProcessId(function(err, ids) {
      if (err) {
        Common.printError(err);
        return cb ? cb(Common.retErr(err)) : that.exitCli(conf.ERROR_EXIT);
      }
      return processIds(ids, cb);
    });
  }
  else if (isNaN(process_name)) {
    that.Client.getProcessIdByName(process_name, function(err, ids) {
      if (err) {
        Common.printError(err);
        return cb ? cb(Common.retErr(err)) : that.exitCli(conf.ERROR_EXIT);
      }
      if (ids.length === 0) {
        Common.printError('Unknown process name');
        return cb ? cb(new Error('Unknown process name')) : that.exitCli(conf.ERROR_EXIT);
      }
      return processIds(ids, cb);
    });
  } else {
    processIds([process_name], cb);
  }
};

/**
 * Update daemonized PM2 Daemon
 *
 * @param {Function} cb callback when pm2 has been upgraded
 */
API.prototype.update = function(cb) {
  var that = this;

  Common.printOut('Be sure to have the latest version by doing `npm install pm2@latest -g` before doing this procedure.');

  // Dump PM2 processes
  that.Client.executeRemote('notifyKillPM2', {}, function() {});

  that.dump(function(err) {
    debug('Dumping successfull', err);
    that.killDaemon(function() {
      debug('------------------ Everything killed', arguments);
      that.Client.launchDaemon({interactor:false}, function(err, child) {
        that.Client.launchRPC(function() {
          that.resurrect(function() {
            Common.printOut(chalk.blue.bold('>>>>>>>>>> PM2 updated'));
            Modularizer.launchAll(that, function() {
              KMDaemon.launchAndInteract(that._conf, null, function(err, data, interactor_proc) {
                // Interactor error can be skipped here
                return cb ? cb(null, {success:true}) : that.speedList();
              });
            });
          });
        });
      });
    });
  });

  return false;
};

/**
 * Graceful Reload an application
 *
 * @param {String} process_name Application Name or All
 * @param {Object} opts         Options
 * @param {Function} cb         Callback
 */
API.prototype.gracefulReload = function(process_name, opts, cb) {
  var that = this;

  if (typeof(opts) == "function") {
    cb = opts;
    opts = {};
  }

  //Common.printOut(conf.PREFIX_MSG_WARNING + chalk.bold.yellow('Warning gracefulReload will be soon deprecated'));
  //Common.printOut(conf.PREFIX_MSG_WARNING + chalk.bold.yellow('Use http://pm2.keymetrics.io/docs/usage/signals-clean-restart/ instead'));

  if (Common.isConfigFile(process_name))
    that._startJson(process_name, commander, 'softReloadProcessId');
  else {
    if (opts && !opts.updateEnv)
      Common.printOut(IMMUTABLE_MSG);
    that._operate('softReloadProcessId', process_name, opts, cb);
  }
};

/**
 * Reload an application
 *
 * @param {String} process_name Application Name or All
 * @param {Object} opts         Options
 * @param {Function} cb         Callback
 */
API.prototype.reload = function(process_name, opts, cb) {
  var that = this;

  if (typeof(opts) == "function") {
    cb = opts;
    opts = {};
  }

  var delay = Common.lockReload();

  if (delay > 0 && opts.force != true) {
    Common.printError(conf.PREFIX_MSG_ERR + 'Reload already in progress, please try again in ' + Math.floor((conf.RELOAD_LOCK_TIMEOUT - delay) / 1000) + ' seconds or use --force');
    return cb ? cb(new Error('Reload in progress')) : that.exitCli(conf.ERROR_EXIT);
  }

  if (Common.isConfigFile(process_name))
    that._startJson(process_name, opts, 'reloadProcessId', function(err, apps) {
      Common.unlockReload();
      if (err)
        return cb ? cb(err) : that.exitCli(conf.ERROR_EXIT);
      return cb ? cb(null, apps) : that.exitCli(conf.SUCCESS_EXIT);;
    });
  else {
    if (opts && !opts.updateEnv)
      Common.printOut(IMMUTABLE_MSG);

    that._operate('reloadProcessId', process_name, opts, function(err, apps) {
      Common.unlockReload();

      if (err)
        return cb ? cb(err) : that.exitCli(conf.ERROR_EXIT);
      return cb ? cb(null, apps) : that.exitCli(conf.SUCCESS_EXIT);;
    });
  }
};

/**
 * Restart process
 *
 * @param {String} cmd   Application Name / Process id / JSON application file / 'all'
 * @param {Object} opts  Extra options to be updated
 * @param {Function} cb  Callback
 */
API.prototype.restart = function(cmd, opts, cb) {
  if (typeof(opts) == "function") {
    cb = opts;
    opts = {};
  }
  var that = this;

  if (typeof(cmd) === 'number')
    cmd = cmd.toString();

  if (cmd == "-") {
    // Restart from PIPED JSON
    process.stdin.resume();
    process.stdin.setEncoding('utf8');
    process.stdin.on('data', function (param) {
      process.stdin.pause();
      that.actionFromJson('restartProcessId', param, opts, 'pipe', cb);
    });
  }
  else if (Common.isConfigFile(cmd) || typeof(cmd) === 'object')
    that._startJson(cmd, opts, 'restartProcessId', cb);
  else {
    if (opts && !opts.updateEnv)
      Common.printOut(IMMUTABLE_MSG);
    that._operate('restartProcessId', cmd, opts, cb);
  }
};

/**
 * Delete process
 *
 * @param {String} process_name Application Name / Process id / Application file / 'all'
 * @param {Function} cb Callback
 */
API.prototype.delete = function(process_name, jsonVia, cb) {
  var that = this;

  if (typeof(jsonVia) === "function") {
    cb = jsonVia;
    jsonVia = null;
  }
  if (typeof(process_name) === "number") {
    process_name = process_name.toString();
  }

  if (jsonVia == 'pipe')
    return that.actionFromJson('deleteProcessId', process_name, commander, 'pipe', cb);
  if (Common.isConfigFile(process_name))
    return that.actionFromJson('deleteProcessId', process_name, commander, 'file', cb);
  else
    that._operate('deleteProcessId', process_name, cb);
};

/**
 * Stop process
 *
 * @param {String} process_name Application Name / Process id / Application file / 'all'
 * @param {Function} cb Callback
 */
API.prototype.stop = function(process_name, cb) {
  var that = this;

  if (typeof(process_name) === 'number')
    process_name = process_name.toString();

  if (process_name == "-") {
    process.stdin.resume();
    process.stdin.setEncoding('utf8');
    process.stdin.on('data', function (param) {
      process.stdin.pause();
      that.actionFromJson('stopProcessId', param, commander, 'pipe', cb);
    });
  }
  else if (Common.isConfigFile(process_name))
    that.actionFromJson('stopProcessId', process_name, commander, 'file', cb);
  else
    that._operate('stopProcessId', process_name, cb);
};

/**
 * Get list of all processes managed
 *
 * @param {Function} cb Callback
 */
API.prototype.list = function(opts, cb) {
  var that = this;

  if (typeof(opts) == 'function') {
    cb = opts;
    opts = null;
  }

  that.Client.executeRemote('getMonitorData', {}, function(err, list) {
    if (err) {
      Common.printError(err);
      return cb ? cb(Common.retErr(err)) : that.exitCli(conf.ERROR_EXIT);
    }

    if (opts && opts.rawArgs && opts.rawArgs.indexOf('--watch') > -1) {
      var moment = require('moment');
      function show() {
        process.stdout.write('\033[2J');
        process.stdout.write('\033[0f');
        console.log('Last refresh: ', moment().format('LTS'));
        that.Client.executeRemote('getMonitorData', {}, function(err, list) {
          UX.dispAsTable(list, null);
        });
      }

      show();
      setInterval(show, 900);
      return false;
    }

    return cb ? cb(null, list) : that.speedList();
  });
};

/**
 * Kill Daemon
 *
 * @param {Function} cb Callback
 */
API.prototype.killDaemon = API.prototype.kill = function(cb) {
  var that = this;

  var semver = require('semver');
  Common.printOut(conf.PREFIX_MSG + 'Stopping PM2...');

  that.Client.executeRemote('notifyKillPM2', {}, function() {});

  that.getVersion(function(err, data) {
    if (!err && semver.lt(data, '1.1.0')) {
      // Disable action command output if upgrading from < 1.1.0 PM2
      // This is in order to avoid duplicated output
      process.env.PM2_SILENT = 'true';
      console.log(conf.PREFIX_MSG + 'Killing processes...');
    }

    that.killAllModules(function() {
      that._operate('deleteProcessId', 'all', function(err, list) {
        Common.printOut(conf.PREFIX_MSG + 'All processes have been stopped and deleted');
        process.env.PM2_SILENT = 'false';

        that.killInteract(function(err, data) {
          that.Client.killDaemon(function(err, res) {
            if (err) Common.printError(err);
            Common.printOut(conf.PREFIX_MSG + 'PM2 stopped');
            return cb ? cb(err, res) : that.exitCli(conf.SUCCESS_EXIT);
          });
        });
      });
    });

  });
};

/////////////////////
// Private methods //
/////////////////////

/**
 * Method to START / RESTART a script
 *
 * @private
 * @param {string} script script name (will be resolved according to location)
 */
API.prototype._startScript = function(script, opts, cb) {
  if (typeof opts == "function") {
    cb = opts;
    opts = {};
  }
  var that = this;

  var app_conf = Config.transCMDToConf(opts);
  var appConf = {};

  if (!!opts.executeCommand)
    app_conf.exec_mode = 'fork';
  else if (opts.instances !== undefined)
    app_conf.exec_mode = 'cluster';
  else
    app_conf.exec_mode = 'fork';

  if (typeof app_conf.name == 'function'){
    delete app_conf.name;
  }

  delete app_conf.args;

  var argsIndex;

  if (opts.rawArgs && (argsIndex = opts.rawArgs.indexOf('--')) >= 0) {
    app_conf.args = opts.rawArgs.slice(argsIndex + 1);
  }
  else if (opts.scriptArgs) {
    app_conf.args = opts.scriptArgs;
  }

  app_conf.script = script;

  if ((appConf = Common.verifyConfs(app_conf)) instanceof Error)
    return cb ? cb(Common.retErr(appConf)) : that.exitCli(conf.ERROR_EXIT);

  app_conf = appConf[0];
  /**
   * If -w option, write configuration to configuration.json file
   */
  if (appConf.write) {
    var dst_path = path.join(process.env.PWD || process.cwd(), app_conf.name + '-pm2.json');
    Common.printOut(conf.PREFIX_MSG + 'Writing configuration to', chalk.blue(dst_path));
    // pretty JSON
    try {
      fs.writeFileSync(dst_path, JSON.stringify(app_conf, null, 2));
    } catch (e) {
      console.error(e.stack || e);
    }
  }

  /**
   * If start <app_name> start/restart application
   */
  function restartExistingProcessName(cb) {
    if (!isNaN(script) ||
        (typeof script === 'string' && script.indexOf('/') != -1) ||
        (typeof script === 'string' && path.extname(script) !== ''))
      return cb(null);

    if (script !== 'all') {
      that.Client.getProcessIdByName(script, function(err, ids) {
        if (err && cb) return cb(err);
        if (ids.length > 0) {
          that._operate('restartProcessId', script, opts, function(err, list) {
            if (err) return cb(err);
            Common.printOut(conf.PREFIX_MSG + 'Process successfully started');
            return cb(true, list);
          });
        }
        else return cb(null);
      });
    }
    else {
      that._operate('restartProcessId', 'all', function(err, list) {
        if (err) return cb(err);
        Common.printOut(conf.PREFIX_MSG + 'Process successfully started');
        return cb(true, list);
      });
    }
  }

  function restartExistingProcessId(cb) {
    if (isNaN(script)) return cb(null);

    that._operate('restartProcessId', script, opts, function(err, list) {
      if (err) return cb(err);
      Common.printOut(conf.PREFIX_MSG + 'Process successfully started');
      return cb(true, list);
    });
  }

  /**
   * Restart a process with the same full path
   * Or start it
   */
  function restartExistingProcessPath(cb) {
    that.Client.executeRemote('getMonitorData', {}, function(err, procs) {
      if (err) return cb ? cb(new Error(err)) : that.exitCli(conf.ERROR_EXIT);

      var full_path = path.resolve(that.cwd, script);
      var managed_script = null;

      procs.forEach(function(proc) {
        if (proc.pm2_env.pm_exec_path == full_path &&
            proc.pm2_env.name == app_conf.name)
          managed_script = proc;
      });

      if (managed_script &&
          (managed_script.pm2_env.status == conf.STOPPED_STATUS ||
           managed_script.pm2_env.status == conf.STOPPING_STATUS ||
           managed_script.pm2_env.status == conf.ERRORED_STATUS)) {
        // Restart process if stopped
        var app_name = managed_script.pm2_env.name;

        that._operate('restartProcessId', app_name, opts, function(err, list) {
          if (err) return cb ? cb(new Error(err)) : that.exitCli(conf.ERROR_EXIT);
          Common.printOut(conf.PREFIX_MSG + 'Process successfully started');
          return cb(true, list);
        });
        return false;
      }
      else if (managed_script && !opts.force) {
        Common.printError(conf.PREFIX_MSG_ERR + 'Script already launched, add -f option to force re-execution');
        return cb(new Error('Script already launched'));
      }

      var resolved_paths = null;

      try {
        resolved_paths = Common.resolveAppAttributes({
          cwd      : that.cwd,
          pm2_home : that.pm2_home
        }, app_conf);
      } catch(e) {
        Common.printError(e);
        return cb(Common.retErr(e));
      }

      Common.printOut(conf.PREFIX_MSG + 'Starting %s in %s (%d instance' + (resolved_paths.instances > 1 ? 's' : '') + ')',
                      resolved_paths.pm_exec_path, resolved_paths.exec_mode, resolved_paths.instances);

      if (!resolved_paths.env) resolved_paths.env = {};

      // Set PM2 HOME in case of child process using PM2 API
      resolved_paths.env['PM2_HOME'] = that.pm2_home;

      var additional_env = Modularizer.getAdditionalConf(resolved_paths.name);
      util._extend(resolved_paths.env, additional_env);

      // Is KM linked?
      resolved_paths.km_link = that.gl_is_km_linked;

      that.Client.executeRemote('prepare', resolved_paths, function(err, data) {
        if (err) {
          Common.printError(conf.PREFIX_MSG_ERR + 'Error while launching application', err.stack || err);
          return cb(Common.retErr(err));
        }

        Common.printOut(conf.PREFIX_MSG + 'Done.');
        return cb(true, data);
      });
      return false;
    });
  }

  async.series([
    restartExistingProcessName,
    restartExistingProcessId,
    restartExistingProcessPath
  ], function(err, data) {

    if (err instanceof Error)
      return cb ? cb(err) : that.exitCli(conf.ERROR_EXIT);

    var ret = {};
    data.forEach(function(_dt) {
      if (_dt !== undefined)
        ret = _dt;
    });

    return cb ? cb(null, ret) : that.speedList();
  });
};

/**
 * Method to start/restart/reload processes from a JSON file
 * It will start app not started
 * Can receive only option to skip applications
 *
 * @private
 */
API.prototype._startJson = function(file, opts, action, pipe, cb) {
  var config     = {};
  var appConf    = {};
  var deployConf = {};
  var apps_info  = [];
  var that = this;

  if (typeof(cb) === 'undefined' && typeof(pipe) === 'function') {
    cb = pipe;
  }

  if (typeof(file) === 'object') {
    config = file;
  } else if (pipe === 'pipe') {
    config = Common.parseConfig(file, 'pipe');
  } else {
    var data = null;

    var isAbsolute = false

    //node 0.11 compatibility #2815
    if (typeof path.isAbsolute === 'function') {
      isAbsolute = path.isAbsolute(file)
    } else {
      isAbsolute = /^\/|\\/.test(file)
    }

    var file_path = isAbsolute ? file : path.join(that.cwd, file);

    debug('Resolved filepath %s', file_path);

    try {
      data = fs.readFileSync(file_path);
    } catch(e) {
      Common.printError(conf.PREFIX_MSG_ERR + 'File ' + file +' not found');
      return cb ? cb(Common.retErr(e)) : that.exitCli(conf.ERROR_EXIT);
    }

    try {
      config = Common.parseConfig(data, file);
    } catch(e) {
      Common.printError(conf.PREFIX_MSG_ERR + 'File ' + file + ' malformated');
      console.error(e);
      return cb ? cb(Common.retErr(e)) : that.exitCli(conf.ERROR_EXIT);
    }
  }

  if (config.deploy)
    deployConf = config.deploy;

  if (config.apps)
    appConf = config.apps;
  else if (config.pm2)
    appConf = config.pm2;
  else
    appConf = config;

  if (!Array.isArray(appConf))
    appConf = [appConf]; //convert to array

  if ((appConf = Common.verifyConfs(appConf)) instanceof Error)
    return cb ? cb(appConf) : that.exitCli(conf.ERROR_EXIT);

  process.env.PM2_JSON_PROCESSING = true;

  // Get App list
  var apps_name = [];
  var proc_list = {};

  // Here we pick only the field we want from the CLI when starting a JSON
  appConf.forEach(function(app) {
    // --only <app>
    if (opts.only && opts.only != app.name)
      return false;
    // --watch
    if (!app.watch && opts.watch && opts.watch === true)
      app.watch = true;
    // --ignore-watch
    if (!app.ignore_watch && opts.ignore_watch)
      app.ignore_watch = opts.ignore_watch;
    // --instances <nb>
    if (opts.instances && typeof(opts.instances) === 'number')
      app.instances = opts.instances;
    // --uid <user>
    if (opts.uid)
      app.uid = opts.uid;
    // --gid <user>
    if (opts.gid)
      app.gid = opts.gid;
    // Specific
    if (app.append_env_to_name && opts.env)
      app.name += ('-' + opts.env);
    apps_name.push(app.name);
  });

  that.Client.executeRemote('getMonitorData', {}, function(err, raw_proc_list) {
    if (err) {
      Common.printError(err);
      return cb ? cb(Common.retErr(err)) : that.exitCli(conf.ERROR_EXIT);
    }

    /**
     * Uniquify in memory process list
     */
    raw_proc_list.forEach(function(proc) {
      proc_list[proc.name] = proc;
    });

    /**
     * Auto detect application already started
     * and act on them depending on action
     */
    async.eachLimit(Object.keys(proc_list), conf.CONCURRENT_ACTIONS, function(proc_name, next) {
      // Skip app name (--only option)
      if (apps_name.indexOf(proc_name) == -1)
        return next();

      if (!(action == 'reloadProcessId' ||
            action == 'softReloadProcessId' ||
            action == 'restartProcessId'))
        throw new Error('Wrong action called');

      var apps = appConf.filter(function(app) {
        return app.name == proc_name;
      });

      var envs = apps.map(function(app){
        // Binds env_diff to env and returns it.
        return Common.mergeEnvironmentVariables(app, opts.env, deployConf);
      });

      // Assigns own enumerable properties of all
      // Notice: if people use the same name in different apps,
      //         duplicated envs will be overrode by the last one
      var env = envs.reduce(function(e1, e2){
        return util._extend(e1, e2);
      });

      // When we are processing JSON, allow to keep the new env by default
      env.updateEnv = true;

      // Pass `env` option
      that._operate(action, proc_name, env, function(err, ret) {
        if (err) Common.printError(err);

        // For return
        apps_info = apps_info.concat(ret);

        that.Client.notifyGod(action, proc_name);
        // And Remove from array to spy
        apps_name.splice(apps_name.indexOf(proc_name), 1);
        return next();
      });

    }, function(err) {
      if (err) return cb ? cb(Common.retErr(err)) : that.exitCli(conf.ERROR_EXIT);
      if (apps_name.length > 0 && action != 'start')
        Common.printOut(conf.PREFIX_MSG_WARNING + 'Applications %s not running, starting...', apps_name.join(', '));
      // Start missing apps
      return startApps(apps_name, function(err, apps) {
        apps_info = apps_info.concat(apps);
        return cb ? cb(err, apps_info) : that.speedList(err ? 1 : 0);
      });
    });
    return false;
  });

  function startApps(app_name_to_start, cb) {
    var apps_to_start = [];
    var apps_started = [];

    appConf.forEach(function(app, i) {
      if (app_name_to_start.indexOf(app.name) != -1) {
        apps_to_start.push(appConf[i]);
      }
    });

    async.eachLimit(apps_to_start, conf.CONCURRENT_ACTIONS, function(app, next) {
      if (opts.cwd)
        app.cwd = opts.cwd;
      if (opts.force_name)
        app.name = opts.force_name;
      if (opts.started_as_module)
        app.pmx_module = true;

      var resolved_paths = null;

      // hardcode script name to use `serve` feature inside a process file
      if (app.script === 'serve') {
        app.script = path.resolve(__dirname, 'API', 'Serve.js')
      }

      try {
        resolved_paths = Common.resolveAppAttributes({
          cwd      : that.cwd,
          pm2_home : that.pm2_home
        }, app);
      } catch (e) {
        return next();
      }

      if (!resolved_paths.env) resolved_paths.env = {};

      // Set PM2 HOME in case of child process using PM2 API
      resolved_paths.env['PM2_HOME'] = that.pm2_home;

      var additional_env = Modularizer.getAdditionalConf(resolved_paths.name);
      util._extend(resolved_paths.env, additional_env);

      resolved_paths.env = Common.mergeEnvironmentVariables(resolved_paths, opts.env, deployConf);

      delete resolved_paths.env.current_conf;

      // Is KM linked?
      resolved_paths.km_link = that.gl_is_km_linked;

      that.Client.executeRemote('prepare', resolved_paths, function(err, data) {
        if (err) {
          Common.printError(conf.PREFIX_MSG_ERR + 'Process failed to launch %s', err.message ? err.message : err);
          return next();
        }
        if (data.length === 0) {
          Common.printError(conf.PREFIX_MSG_ERR + 'Process config loading failed', data);
          return next();
        }

        Common.printOut(conf.PREFIX_MSG + 'App [%s] launched (%d instances)', data[0].pm2_env.name, data.length);
        apps_started = apps_started.concat(data);
        next();
      });

    }, function(err) {
      return cb ? cb(err || null, apps_started) : that.speedList();
    });
    return false;
  }
};

/**
 * Apply a RPC method on the json file
 * @private
 * @method actionFromJson
 * @param {string} action RPC Method
 * @param {object} options
 * @param {string|object} file file
 * @param {string} jsonVia action type (=only 'pipe' ?)
 * @param {Function}
 */
API.prototype.actionFromJson = function(action, file, opts, jsonVia, cb) {
  var appConf = {};
  var ret_processes = [];
  var that = this;

  //accept programmatic calls
  if (typeof file == 'object') {
    cb = typeof jsonVia == 'function' ? jsonVia : cb;
    appConf = file;
  }
  else if (jsonVia == 'file') {
    var data = null;

    try {
      data = fs.readFileSync(file);
    } catch(e) {
      Common.printError(conf.PREFIX_MSG_ERR + 'File ' + file +' not found');
      return cb ? cb(Common.retErr(e)) : that.exitCli(conf.ERROR_EXIT);
    }

    try {
      appConf = Common.parseConfig(data, file);
    } catch(e) {
      Common.printError(conf.PREFIX_MSG_ERR + 'File ' + file + ' malformated');
      console.error(e);
      return cb ? cb(Common.retErr(e)) : that.exitCli(conf.ERROR_EXIT);
    }
  } else if (jsonVia == 'pipe') {
    appConf = Common.parseConfig(file, 'pipe');
  } else {
    Common.printError('Bad call to actionFromJson, jsonVia should be one of file, pipe');
    return that.exitCli(conf.ERROR_EXIT);
  }

  // Backward compatibility
  if (appConf.apps)
    appConf = appConf.apps;

  if (!Array.isArray(appConf))
    appConf = [appConf];

  if ((appConf = Common.verifyConfs(appConf)) instanceof Error)
    return cb ? cb(appConf) : that.exitCli(conf.ERROR_EXIT);

  async.eachLimit(appConf, conf.CONCURRENT_ACTIONS, function(proc, next1) {
    var name = '';
    var new_env;

    if (!proc.name)
      name = path.basename(proc.script);
    else
      name = proc.name;

    if (opts.only && opts.only != name)
      return process.nextTick(next1);

    if (opts && opts.env)
      new_env = Common.mergeEnvironmentVariables(proc, opts.env);
    else
      new_env = Common.mergeEnvironmentVariables(proc);

    that.Client.getProcessIdByName(name, function(err, ids) {
      if (err) {
        Common.printError(err);
        return next1();
      }
      if (!ids) return next1();

      async.eachLimit(ids, conf.CONCURRENT_ACTIONS, function(id, next2) {
        var opts = {};

        //stopProcessId could accept options to?
        if (action == 'restartProcessId') {
          opts = {id : id, env : new_env};
        } else {
          opts = id;
        }

        that.Client.executeRemote(action, opts, function(err, res) {
          ret_processes.push(res);
          if (err) {
            Common.printError(err);
            return next2();
          }

          if (action == 'restartProcessId') {
            that.Client.notifyGod('restart', id);
          } else if (action == 'deleteProcessId') {
            that.Client.notifyGod('delete', id);
          } else if (action == 'stopProcessId') {
            that.Client.notifyGod('stop', id);
          }

          Common.printOut(conf.PREFIX_MSG + '[%s](%d) \u2713', name, id);
          return next2();
        });
      }, function(err) {
        return next1(null, ret_processes);
      });
    });
  }, function(err) {
    if (cb) return cb(null, ret_processes);
    else return that.speedList();
  });
};


/**
 * Main function to operate with PM2 daemon
 *
 * @param {String} action_name  Name of action (restartProcessId, deleteProcessId, stopProcessId)
 * @param {String} process_name can be 'all', a id integer or process name
 * @param {Object} envs         object with CLI options / environment
 */
API.prototype._operate = function(action_name, process_name, envs, cb) {
  var that = this;
  var update_env = false;
  var ret = [];

  // Make sure all options exist
  if (!envs)
    envs = {};

  if (typeof(envs) == 'function'){
    cb = envs;
    envs = {};
  }

  // Set via env.update (JSON processing)
  if (envs.updateEnv === true)
    update_env = true;

  var concurrent_actions = envs.parallel || conf.CONCURRENT_ACTIONS;

  if (!process.env.PM2_JSON_PROCESSING || envs.commands) {
    envs = that._handleAttributeUpdate(envs);
  }

  /**
   * Set current updated configuration if not passed
   */
  if (!envs.current_conf) {
    var _conf = fclone(envs);
    envs = {
      current_conf : _conf
    }

    // Is KM linked?
    envs.current_conf.km_link = that.gl_is_km_linked;
  }

  /**
   * Operate action on specific process id
   */
  function processIds(ids, cb) {
    Common.printOut(conf.PREFIX_MSG + 'Applying action %s on app [%s](ids: %s)', action_name, process_name, ids);

    if (action_name == 'deleteProcessId')
      concurrent_actions = 10;

    async.eachLimit(ids, concurrent_actions, function(id, next) {
      var opts;

      // These functions need extra param to be passed
      if (action_name == 'restartProcessId' ||
          action_name == 'reloadProcessId' ||
          action_name == 'softReloadProcessId') {
        var new_env = {};

        if (update_env === true) {
          if (conf.PM2_PROGRAMMATIC == true)
            new_env = Common.safeExtend({}, process.env);
          else
            new_env = util._extend({}, process.env);

          Object.keys(envs).forEach(function(k) {
            new_env[k] = envs[k];
          });
        }
        else {
          new_env = envs;
        }

        opts = {
          id  : id,
          env : new_env
        };
      }
      else {
        opts = id;
      }

      that.Client.executeRemote(action_name, opts, function(err, res) {
        if (err) {
          Common.printError(conf.PREFIX_MSG_ERR + 'Process %s not found', id);
          return next('Process not found');
        }

        if (action_name == 'restartProcessId') {
          that.Client.notifyGod('restart', id);
        } else if (action_name == 'deleteProcessId') {
          that.Client.notifyGod('delete', id);
        } else if (action_name == 'stopProcessId') {
          that.Client.notifyGod('stop', id);
        } else if (action_name == 'reloadProcessId') {
          that.Client.notifyGod('reload', id);
        } else if (action_name == 'softReloadProcessId') {
          that.Client.notifyGod('graceful reload', id);
        }

        if (!Array.isArray(res))
          res = [res];

        // Filter return
        res.forEach(function(proc) {
          Common.printOut(conf.PREFIX_MSG + '[%s](%d) \u2713', proc.pm2_env ? proc.pm2_env.name : process_name, id);

          if (!proc.pm2_env) return false;

          ret.push({
            name         : proc.pm2_env.name,
            pm_id        : proc.pm2_env.pm_id,
            status       : proc.pm2_env.status,
            restart_time : proc.pm2_env.restart_time,
            pm2_env : {
              name         : proc.pm2_env.name,
              pm_id        : proc.pm2_env.pm_id,
              status       : proc.pm2_env.status,
              restart_time : proc.pm2_env.restart_time,
              env          : proc.pm2_env.env
            }
          });
        });

        return next();
      });
    }, function(err) {
      if (err) return cb ? cb(Common.retErr(err)) : that.exitCli(conf.ERROR_EXIT);
      return cb ? cb(null, ret) : that.speedList();
    });
  }

  if (process_name == 'all') {
    that.Client.getAllProcessId(function(err, ids) {
      if (err) {
        Common.printError(err);
        return cb ? cb(Common.retErr(err)) : that.exitCli(conf.ERROR_EXIT);
      }
      if (!ids || ids.length === 0) {
        Common.printError(conf.PREFIX_MSG_WARNING + 'No process found');
        return cb ? cb(new Error('process name not found')) : that.exitCli(conf.ERROR_EXIT);
      }

      return processIds(ids, cb);
    });
  }
  // operate using regex
  else if (isNaN(process_name) && process_name[0] === '/' && process_name[process_name.length - 1] === '/') {
    var regex = new RegExp(process_name.replace(/\//g, ''));

    that.Client.executeRemote('getMonitorData', {}, function(err, list) {
      if (err) {
        Common.printError('Error retrieving process list: ' + err);
        return cb(err);
      }
      var found_proc = [];
      list.forEach(function(proc) {
        if (regex.test(proc.pm2_env.name)) {
          found_proc.push(proc.pm_id);
        }
      });

      if (found_proc.length === 0) {
        Common.printError(conf.PREFIX_MSG_WARNING + 'No process found');
        return cb ? cb(new Error('process name not found')) : that.exitCli(conf.ERROR_EXIT);
      }

      return processIds(found_proc, cb);
    });
  }
  else if (isNaN(process_name)) {
    /**
     * We can not stop or delete a module but we can restart it
     * to refresh configuration variable
     */
    var allow_module_restart = action_name == 'restartProcessId' ? true : false;

    that.Client.getProcessIdByName(process_name, allow_module_restart, function(err, ids) {
      if (err) {
        Common.printError(err);
        return cb ? cb(Common.retErr(err)) : that.exitCli(conf.ERROR_EXIT);
      }
      if (!ids || ids.length === 0) {
        Common.printError(conf.PREFIX_MSG_ERR + 'Process %s not found', process_name);
        return cb ? cb(new Error('process name not found')) : that.exitCli(conf.ERROR_EXIT);
      }

      /**
       * Determine if the process to restart is a module
       * if yes load configuration variables and merge with the current environment
       */
      var additional_env = Modularizer.getAdditionalConf(process_name);
      util._extend(envs, additional_env);

      return processIds(ids, cb);
    });
  } else {
    // Check if application name as number is an app name
    that.Client.getProcessIdByName(process_name, function(err, ids) {
      if (ids.length > 0)
        return processIds(ids, cb);
      // Else operate on pm id
      return processIds([process_name], cb);
    });
  }
};

/**
 * Converts CamelCase Commander.js arguments
 * to Underscore
 * (nodeArgs -> node_args)
 */
API.prototype._handleAttributeUpdate = function(opts) {
  var conf = Config.transCMDToConf(opts);
  var that = this;

  if (typeof(conf.name) != 'string')
    delete conf.name;

  var argsIndex = 0;
  if (opts.rawArgs && (argsIndex = opts.rawArgs.indexOf('--')) >= 0) {
    conf.args = opts.rawArgs.slice(argsIndex + 1);
  }

  var appConf = Common.verifyConfs(conf)[0];

  if (appConf instanceof Error) {
    Common.printError('Error while transforming CamelCase args to underscore');
    return appConf;
  }

  if (argsIndex == -1)
    delete appConf.args;
  if (appConf.name == 'undefined')
    delete appConf.name;

  delete appConf.exec_mode;

  if (util.isArray(appConf.watch) && appConf.watch.length === 0) {
    if (!~opts.rawArgs.indexOf('--watch'))
      delete appConf.watch
  }

  // Force deletion of defaults values set by commander
  // to avoid overriding specified configuration by user
  if (appConf.treekill === true)
    delete appConf.treekill;
  if (appConf.pmx === true)
    delete appConf.pmx;
  if (appConf.vizion === true)
    delete appConf.vizion;
  if (appConf.automation === true)
    delete appConf.automation;
  if (appConf.autorestart === true)
    delete appConf.autorestart;

  return appConf;
};

API.prototype.getProcessIdByName = function(name, cb) {
  var that = this;

  this.Client.getProcessIdByName(name, function(err, id) {
    if (err) {
      Common.printError(err);
      return cb ? cb(Common.retErr(err)) : that.exitCli(conf.ERROR_EXIT);
    }
    console.log(id);
    return cb ? cb(null, id) : that.exitCli(conf.SUCCESS_EXIT);
  });
};

/**
 * Description
 * @method jlist
 * @param {} debug
 * @return
 */
API.prototype.jlist = function(debug) {
  var that = this;

  that.Client.executeRemote('getMonitorData', {}, function(err, list) {
    if (err) {
      Common.printError(err);
      that.exitCli(conf.ERROR_EXIT);
    }

    if (debug) {
      process.stdout.write(util.inspect(list, false, null, false));
    }
    else {
      process.stdout.write(JSON.stringify(list));
    }

    that.exitCli(conf.SUCCESS_EXIT);

  });
};

var gl_retry = 0;

/**
 * Description
 * @method speedList
 * @return
 */
API.prototype.speedList = function(code) {
  var that = this;

  // Do nothing if PM2 called programmatically and not called from CLI (also in exitCli)
  if (conf.PM2_PROGRAMMATIC && process.env.PM2_USAGE != 'CLI') return false;

  that.Client.executeRemote('getMonitorData', {}, function(err, list) {
    if (err) {
      if (gl_retry == 0) {
        gl_retry += 1;
        return setTimeout(that.speedList.bind(that), 1400);
      }
      console.error('Error retrieving process list: %s.\nA process seems to be on infinite loop, retry in 5 seconds',err);
      return that.exitCli(conf.ERROR_EXIT);
    }
    if (process.stdout.isTTY === false) {
      UX.miniDisplay(list);
    }
    else if (commander.miniList && !commander.silent)
      UX.miniDisplay(list);
    else if (!commander.silent) {
      if (that.gl_interact_infos) {
        Common.printOut(chalk.green.bold('●') + ' Agent Online | Dashboard Access: ' + chalk.bold('https://app.keymetrics.io/#/r/%s') + ' | Server name: %s', that.gl_interact_infos.public_key, that.gl_interact_infos.machine_name);
      }
      UX.dispAsTable(list, that.gl_interact_infos);
      Common.printOut(chalk.white.italic(' Use `pm2 show <id|name>` to get more details about an app'));
    }

    if (that.Client.daemon_mode == false) {
      Common.printOut('[--no-daemon] Continue to stream logs');
      Common.printOut('[--no-daemon] Exit on target PM2 exit pid=' + fs.readFileSync(conf.PM2_PID_FILE_PATH).toString());
      global._auto_exit = true;
      return that.streamLogs('all', 0, false, 'HH:mm:ss', false);
    }
    else if (commander.attach === true) {
      return that.streamLogs('all', 0, false, null, false);
    }
    else {
      return that.exitCli(code ? code : conf.SUCCESS_EXIT);
    }
  });
}

/**
 * Scale up/down a process
 * @method scale
 */
API.prototype.scale = function(app_name, number, cb) {
  var that = this;

  function addProcs(proc, value, cb) {
    (function ex(proc, number) {
      if (number-- === 0) return cb();
      Common.printOut(conf.PREFIX_MSG + 'Scaling up application');
      that.Client.executeRemote('duplicateProcessId', proc.pm2_env.pm_id, ex.bind(this, proc, number));
    })(proc, number);
  }

  function rmProcs(procs, value, cb) {
    var i = 0;

    (function ex(procs, number) {
      if (number++ === 0) return cb();
      that._operate('deleteProcessId', procs[i++].pm2_env.pm_id, ex.bind(this, procs, number));
    })(procs, number);
  }

  function end() {
    return cb ? cb(null, {success:true}) : that.speedList();
  }

  this.Client.getProcessByName(app_name, function(err, procs) {
    if (err) {
      Common.printError(err);
      return cb ? cb(Common.retErr(err)) : that.exitCli(conf.ERROR_EXIT);
    }

    if (!procs || procs.length === 0) {
      Common.printError(conf.PREFIX_MSG_ERR + 'Application %s not found', app_name);
      return cb ? cb(new Error('App not found')) : that.exitCli(conf.ERROR_EXIT);
    }

    var proc_number = procs.length;

    if (typeof(number) === 'string' && number.indexOf('+') >= 0) {
      number = parseInt(number, 10);
      return addProcs(procs[0], number, end);
    }
    else if (typeof(number) === 'string' && number.indexOf('-') >= 0) {
      number = parseInt(number, 10);
      return rmProcs(procs[0], number, end);
    }
    else {
      number = parseInt(number, 10);
      number = number - proc_number;

      if (number < 0)
        return rmProcs(procs, number, end);
      else if (number > 0)
        return addProcs(procs[0], number, end);
      else {
        Common.printError(conf.PREFIX_MSG_ERR + 'Nothing to do');
        return cb ? cb(new Error('Same process number')) : that.exitCli(conf.ERROR_EXIT);
      }
    }
  });
};

/**
 * Description
 * @method describeProcess
 * @param {} pm2_id
 * @return
 */
API.prototype.describe = function(pm2_id, cb) {
  var that = this;

  var found_proc = [];

  that.Client.executeRemote('getMonitorData', {}, function(err, list) {
    if (err) {
      Common.printError('Error retrieving process list: ' + err);
      that.exitCli(conf.ERROR_EXIT);
    }

    list.forEach(function(proc) {
      if ((!isNaN(pm2_id)    && proc.pm_id == pm2_id) ||
          (typeof(pm2_id) === 'string' && proc.name  == pm2_id)) {
        found_proc.push(proc);
      }
    });

    if (found_proc.length === 0) {
      Common.printError(conf.PREFIX_MSG_WARNING + '%s doesn\'t exist', pm2_id);
      return cb ? cb(null, []) : that.exitCli(conf.ERROR_EXIT);
    }

    if (!cb) {
      found_proc.forEach(function(proc) {
        UX.describeTable(proc);
      });
    }

    return cb ? cb(null, found_proc) : that.exitCli(conf.SUCCESS_EXIT);
  });
};

/**
 * API method to perform a deep update of PM2
 * @method deepUpdate
 */
API.prototype.deepUpdate = function(cb) {
  var that = this;

  Common.printOut(conf.PREFIX_MSG + 'Updating PM2...');

  var exec = require('shelljs').exec;
  var child = exec("npm i -g pm2@latest; pm2 update", {async : true});

  child.stdout.on('end', function() {
    Common.printOut(conf.PREFIX_MSG + 'PM2 successfully updated');
    cb ? cb(null, {success:true}) : that.exitCli(conf.SUCCESS_EXIT);
  });
};