var cluster  = require('cluster');
var fs       = require('fs');
var util     = require('util');
var _ = require('underscore')._;

var optimist = require('optimist');
var argv = optimist.argv;
var script;
var name = "";

console.log = _.wrap(console.log, function(fn) {
  process.stdout.write(name + " ");
  fn.apply(this, _.rest(arguments));
});

function sub() {
  var vm = require('vm');
  name = util.format("[S-%s]", process.pid);
  process.on('message', function(m) {
    eval(m, script);
  });
  process.stdin.end();
}

function main() {
  name = util.format("   [M-%s]", process.pid);
  var code = fs.readFileSync(script, 'utf8');

  function _forkChild() {
    var child = cluster.fork();
    console.log("Starting [%s] (%s)", script, child.pid);
    child.send(code);
  }
  var forkChild = _.throttle(_forkChild, 1000);

  function childDeath(child) {
    console.log("Died     [%s] (%s)", script,  child.pid);
    forkChild();
  }

  cluster.on('death', childDeath);
  forkChild();
};

if(!module.parent) {
  if(argv._.length != 1) {
    throw new Error("One script must be passed");
  }
  script = argv._[0];
  if(cluster.isMaster) {
    main();
  } else {
    sub();
  }
}