/**
 * 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.
 *
 * This file wrap target application
 * - redirect stdin, stderr to bus + log files
 * - rename process
 * - pid
 */

var p       = require('path');
var cst     = require('../constants');
var Utility = require('./Utility.js');
var ProcessUtils = require('./ProcessUtils');

// Load all env-vars from master.
var pm2_env = JSON.parse(process.env.pm2_env);
for(var k in pm2_env) {
  process.env[k] = pm2_env[k];
}

// Rename process
process.title = process.env.PROCESS_TITLE || 'node ' + pm2_env.pm_exec_path;

delete process.env.pm2_env;

/**
 * Main entrance to wrap the desired code
 */
(function ProcessContainer() {
  var fs          = require('fs');

  ProcessUtils.injectModules()

  var stdFile     = pm2_env.pm_log_path;
  var outFile     = pm2_env.pm_out_log_path;
  var errFile     = pm2_env.pm_err_log_path;
  var pidFile     = pm2_env.pm_pid_path;
  var script      = pm2_env.pm_exec_path;

  var original_send = process.send;

  if (typeof(process.env.source_map_support) != 'undefined' &&
      process.env.source_map_support !== 'false') {
    require('source-map-support').install();
  }

  process.send = function() {
    if (process.connected)
      original_send.apply(this, arguments);
  };

  //send node version
  if (process.versions && process.versions.node) {
    process.send({
      'node_version': process.versions.node
    });
  }

  if (cst.MODIFY_REQUIRE)
    require.main.filename = pm2_env.pm_exec_path;

  // Resets global paths for require()
  require('module')._initPaths();

  try {
    fs.writeFileSync(pidFile, process.pid);
  } catch (e) {
    console.error(e.stack || e);
  }

  // Add args to process if args specified on start
  if (process.env.args != null)
    process.argv = process.argv.concat(pm2_env.args);

  // stdio, including: out, err and entire (both out and err if necessary).
  var stds = {
    out: outFile,
    err: errFile
  };
  stdFile && (stds.std = stdFile);

  // uid/gid management
  if (pm2_env.uid || pm2_env.gid) {
    try {
      if (pm2_env.uid)
        process.setuid(pm2_env.uid);
      if (process.env.gid)
        process.setgid(pm2_env.gid);
    } catch(e) {
      setTimeout(function() {
        console.error('%s on call %s', e.message, e.syscall);
        console.error('%s is not accessible', pm2_env.uid);
        return process.exit(1);
      }, 100);
    }
  }

  exec(script, stds);
})();

/**
 * Description
 * @method exec
 * @param {} script
 * @param {} stds
 * @return
 */
function exec(script, stds) {
  if (p.extname(script) == '.coffee') {
    try {
      require('coffee-script/register');
    } catch (e) {
      console.error('Failed to load CoffeeScript interpreter:', e.message || e);
    }
  }

  if (p.extname(script) == '.ls') {
    try {
      require('livescript');
    } catch (e) {
      console.error('Failed to load LiveScript interpreter:', e.message || e);
    }
  }

  if (p.extname(script) == '.ts' || p.extname(script) == '.tsx') {
    try {
      require('ts-node/register');
    } catch (e) {
      console.error('Failed to load Typescript interpreter:', e.message || e);
    }
  }

  process.on('message', function (msg) {
    if (msg.type === 'log:reload') {
      for (var k in stds){
        if (typeof stds[k] == 'object' && !isNaN(stds[k].fd)){
          if (stds[k].destroy) stds[k].destroy();
          else if (stds[k].end) stds[k].end();
          else if (stds[k].close) stds[k].close();
          stds[k] = stds[k]._file;
        }
      }
      Utility.startLogging(stds, function (err) {
        if (err)
          return console.error('Failed to reload logs:', err.stack);
        console.log('Reloading log...');
      });
    }
  });

  var dateFns = null;

  if (pm2_env.log_date_format)
    dateFns = require('date-fns');

  Utility.startLogging(stds, function (err) {
    if (err) {
      process.send({
        type    : 'process:exception',
        data    : {
          message: err.message,
          syscall: 'ProcessContainer.startLogging'
        }
      });
      throw err;
      return;
    }

    process.stderr.write = (function(write) {
      return function(string, encoding, cb) {
        var log_data = null;

        // Disable logs if specified
        if (pm2_env.disable_logs === true) {
          return cb ? cb() : false;
        }

        if (pm2_env.log_type && pm2_env.log_type === 'json') {
          log_data = JSON.stringify({
            message : string.toString(),
            timestamp : pm2_env.log_date_format && dateFns ?
              dateFns.format(Date.now(), pm2_env.log_date_format) : new Date().toISOString(),
            type : 'err',
            process_id : pm2_env.pm_id,
            app_name : pm2_env.name
          }) + '\n';
        }
        else if (pm2_env.log_date_format && dateFns)
          log_data = `${dateFns.format(Date.now(), pm2_env.log_date_format)}: ${string.toString()}`;
        else
          log_data = string.toString();

        process.send({
          type : 'log:err',
          topic : 'log:err',
          data : log_data
        });

        if (Utility.checkPathIsNull(pm2_env.pm_err_log_path) &&
          (!pm2_env.pm_log_path || Utility.checkPathIsNull(pm2_env.pm_log_path)))
          return cb ? cb() : false;

        stds.std && stds.std.write && stds.std.write(log_data, encoding);
        stds.err && stds.err.write && stds.err.write(log_data, encoding, cb);
      };
    })(process.stderr.write);

    process.stdout.write = (function(write) {
      return function(string, encoding, cb) {
        var log_data = null;

        // Disable logs if specified
        if (pm2_env.disable_logs === true) {
          return cb ? cb() : false;
        }

        if (pm2_env.log_type && pm2_env.log_type === 'json') {
          log_data = JSON.stringify({
            message : string.toString(),
            timestamp : pm2_env.log_date_format && dateFns ?
              dateFns.format(Date.now(), pm2_env.log_date_format) : new Date().toISOString(),
            type : 'out',
            process_id : pm2_env.pm_id,
            app_name : pm2_env.name
          }) + '\n';
        }
        else if (pm2_env.log_date_format && dateFns)
          log_data = `${dateFns.format(Date.now(), pm2_env.log_date_format)}: ${string.toString()}`;
        else
          log_data = string.toString();

        process.send({
          type : 'log:out',
          data : log_data
        });

        if (Utility.checkPathIsNull(pm2_env.pm_out_log_path) &&
          (!pm2_env.pm_log_path || Utility.checkPathIsNull(pm2_env.pm_log_path)))
          return cb ? cb() : null;

        stds.std && stds.std.write && stds.std.write(log_data, encoding);
        stds.out && stds.out.write && stds.out.write(log_data, encoding, cb);
      };
    })(process.stdout.write);

    function getUncaughtExceptionListener(listener) {
      return function uncaughtListener(err) {
        var error = err && err.stack ? err.stack : err;

        if (listener === 'unhandledRejection') {
          error = 'You have triggered an unhandledRejection, you may have forgotten to catch a Promise rejection:\n' + error;
        }

        logError(['std', 'err'], error);

        // Notify master that an uncaughtException has been catched
        try {
          if (err) {
            var errObj = {};

            Object.getOwnPropertyNames(err).forEach(function(key) {
              errObj[key] = err[key];
            });
          }

          process.send({
            type : 'log:err',
            topic : 'log:err',
            data : '\n' + error + '\n'
          });
          process.send({
            type    : 'process:exception',
            data    : errObj !== undefined ? errObj : {message: 'No error but ' + listener + ' was caught!'}
          });
        } catch(e) {
          logError(['std', 'err'], 'Channel is already closed can\'t broadcast error:\n' + e.stack);
        }

        if (!process.listeners(listener).filter(function (listener) {
            return listener !== uncaughtListener;
        }).length) {
          if (listener == 'uncaughtException') {
            process.emit('disconnect');
            process.exit(cst.CODE_UNCAUGHTEXCEPTION);
          }
        }
      }
    }

    process.on('uncaughtException', getUncaughtExceptionListener('uncaughtException'));
    process.on('unhandledRejection', getUncaughtExceptionListener('unhandledRejection'));

    // Change dir to fix process.cwd
    process.chdir(pm2_env.pm_cwd || process.env.PWD || p.dirname(script));

    if (ProcessUtils.isESModule(script) === true)
      import(process.env.pm_exec_path);
    else
      require('module')._load(script, null, true);

    function logError(types, error){
      try {
        types.forEach(function(type){
          stds[type] && typeof stds[type].write == 'function' && stds[type].write(error + '\n');
        });
      } catch(e) { }
    }
  });

}
