#!/usr/bin/nodejs

var instances = new Array();

 

function Status(i,m) {

  this.id = i;

  this.message = m;

  var self = this;

  this.update = function(i,m) {

    self.id = i;

    self.message = m;

  }

}

 

function Execution(c,d,e,n,v,ins) {

  var code = this.code = c;

  var data = this.data = d;

  var endpoints = this.endpoints = e;

  var output = this.output = false;

  var state = this.state = "not executed";

  var instance = this.instance = ins;

  var status = this.status = new Status(0,'');

  

  if (typeof(n) != 'undefined' && typeof(v) != 'undefined') {

    var result_name = this.result_name = n;

    var result_value = this.result_value = v;

  }  

}

 

// New Execution

function postScript(req, res, next) {

  if (!("dataelements" in req.params)) { return next(new restify.InvalidArgumentError("No dataelements")); }

  if (!("endpoints" in req.params))    { return next(new restify.InvalidArgumentError("No endpoints")); }

  if (!("code" in req.params))         { return next(new restify.InvalidArgumentError("No code")); }

 

  var dataelements = JSON.parse(req.params.dataelements);

  var endpoints = JSON.parse(req.params.endpoints);

  var code = req.params.code;

 

  // for asynchronous execution

  var callback = req.params.callback;

 

  // var instanceCounter;

  instances.push(0);

  var instanceCounter = instances.length-1;

 

  var t = new Execution(code,dataelements,endpoints,req.params.resultname,req.params.resultvalue,instanceCounter);

 

  //callback defined, asyn execution

  if (typeof(callback) != 'undefined') {

    res.contentType = 'text/plain';

    res.send(200,instanceCounter.toString());

  }

 

  var worker = new webworker(function(){

    function ExecutionResult(d,e,o,s) {

      this.data      = d;

      this.endpoints = e;

      this.output    = o;

      this.status    = s;

    }

 

    onmessage = function (exec) {

      var data      = exec.data.data;

      var endpoints = exec.data.endpoints;

      var status    = exec.data.status;

 

      try {

        eval('var ' + exec.data.result_name + ' = JSON.parse(exec.data.result_value)');

 

        var output = eval(exec.data.code);

        var exres  = new ExecutionResult(data,endpoints,output,status);

        

        postMessage(exres);

      } catch (e) {

        console.log(e.message);

        var exres = new ExecutionResult();

        exres.error = e.message;

        postMessage(exres);

      }

    }

  });

 

  // receiving data from worker after execution

  worker.onmessage = function (exres) {

    t.data      = exres.data.data;

    t.endpoints = exres.data.endpoints;

    t.status    = exres.data.status

    t.output    = exres.data.output;

    t.error     = exres.data.error;

    t.result    = exres.data.result;

    worker.terminate();

     

    if (typeof(callback) == 'undefined') {

      if (typeof(t.error) != 'undefined') { // there is an error

        delete instances[t.instance];

        return next(new restify.InternalError(t.error));

      } else { // there is NOOOOO error

        t.state = "executed";

        res.contentType = 'text/plain';

        res.send(200,t.instance.toString());

      }

    } else {

 

      var client = restify.createStringClient({

        url: callback,

        version: '*'

      });

 

      if (typeof(t.error) != 'undefined') { // there is an error

        delete instances[t.instance];

        client.post('',{instance:"error"},function (err,req,res,obj){ if (err) { console.log(err); } });

      } else {  // there is NOOOOO error

        t.state = "executed";

        client.post('', {instance: t.instance.toString()},function (err,req,res,obj){ if (err) { console.log(err); } });

      }

      

    }

  };

 

  // pass code and vars to worker

  instances[t.instance] = t;

  worker.postMessage(t);

}

 

// read Execution details

function getDataelements(req, res, next){

  var id = req.params.instance;

  if (!(id in instances)) { return next(new restify.InvalidArgumentError("No instance")); }

  res.contentType = 'application/json';

  res.send(instances[id].data);

}  

function getEndpoints(req, res, next){

  var id = req.params.instance;

  if (!(id in instances)) { return next(new restify.InvalidArgumentError("No instance")); }

  res.contentType = 'application/json';

  res.send(instances[id].endpoints);

}  

function getStatus(req, res, next){

  var id = req.params.instance;

  if (!(id in instances)) { return next(new restify.InvalidArgumentError("No instance")); }

  res.contentType = 'application/json';

  res.send(instances[id].status);

}  

function getOutput(req, res, next){

  var id = req.params.instance;

  if (!(id in instances)) { return next(new restify.InvalidArgumentError("No instance")); }

  if (instances[id].output == false) {

    res.contentType = 'text/plain';

    res.send('false');

  } else {

    res.contentType = 'application/json';

    res.send(200,instances[id].output);

  }

}

function getState(req, res, next){

  var id = req.params.instance;

  if (!(id in instances)) { return next(new restify.InvalidArgumentError("No instance")); }

  res.contentType = 'application/json';

  res.send(instances[id].state);

}

 

function getFull(req, res, next) {

  var id = req.params.instance;

  if (!(id in instances)) { return next(new restify.InvalidArgumentError("No instance")); }

  res.contentType = 'application/json';

  res.send({ 'endpoints': instances[id].endpoints, 'dataelements': instances[id].data, 'output': instances[id].output, 'status': instances[id].status, 'state': instances[id].state });

}

 

function riddlDesc(req, res, next) {

  res.contentType = 'text/plain';

  res.send(200,"Nothing to see here. Move along.");

}

 

function deleteInstance(req,res,next) {

  var id = req.params.instance;

  if (!(id in instances)) {

    res.contentType = 'text/plain';

    res.send(500,"instance "+id+" not existing");

  }

  delete instances[id];

  res.send(200);

}

 

/************/

/*** MAIN ***/

/************/

var port = '9292';

var host = '0.0.0.0';

 

var restify   = require('restify');

var daemon    = require('daemon');

var opt       = require('optimist');

var url       = require('url');

var fs        = require('fs');

var webworker = require('webworker-threads').Worker;

 

var server = restify.createServer();

server.use(restify.queryParser());

server.use(restify.bodyParser());

server.use(restify.CORS());

 

server.get('/', riddlDesc);

server.post('/', postScript);

server.get('/:instance', getFull);

server.get('/:instance/dataelements', getDataelements);

server.get('/:instance/endpoints', getEndpoints);

server.get('/:instance/status', getStatus);

server.get('/:instance/output', getOutput);

server.get('/:instance/state', getState);

server.del('/:instance', deleteInstance);

 

var argv = opt

  .usage("Usage:\n  $0 [options] start|stop|info")

  .boolean('v')

  .alias('v','verbose')

  .boolean('h')

  .alias('h','help')

  .describe('h','available options.')

  .describe('v','do not daemonize server.')

  .argv;

 

try {

  var pid = fs.readFileSync(process.argv[1].replace(/(\.[^\.]+)?$/,'.pid'),{encoding: 'utf-8'});

} catch(err) {

  var pid = -1;

}

switch (argv._[0]) {

  case "stop":

    if (pid != -1) process.kill(pid);

    break;

 

  case "start":

    try {

      if (pid != -1) {

        process.kill(pid,0);

        console.log('server already running');

        break;

      }  

    } catch(err) { }

    if (argv['v']) {

      server.listen(port, host, function() {

        console.log('%s listening at %s', server.name, host + ':' + port);

        fs.writeFile(process.argv[1].replace(/(\.[^\.]+)?$/,'.pid'),process.pid);

      });

    } else {

      server.listen(port, host, function() {

        console.log('%s listening at %s', server.name, host + ':' + port);

        daemon();

        fs.writeFile(process.argv[1].replace(/(\.[^\.]+)?$/,'.pid'),process.pid);

      });

    }  

    break;

 

  case "info":

    try {

      if (pid == -1) shit();

      process.kill(pid,0);

    } catch(err) {

      console.log('no server running');

      break;

    }

    console.log('%s listening at %s, PID %s', server.name, host + ':' + port, pid);

    break;

 

  default:

    var help = opt.help().replace(/\n\s*\n/,"\n");

    help += '  start          Start the server.\n  stop           Stop the server.\n  info           Get information about the server.';

    console.log(help);

}