// In this benchmark, we connect a client to the server, and write
// as many bytes as we can in the specified time (default = 10s)

var common = require('../common.js');
var util = require('util');

// if there are --dur=N and --len=N args, then
// run the function with those settings.
// if not, then queue up a bunch of child processes.
var bench = common.createBenchmark(main, {
  len: [102400, 1024 * 1024 * 16],
  type: ['utf', 'asc', 'buf'],
  dur: [5]
});

var TCP = process.binding('tcp_wrap').TCP;
var PORT = common.PORT;

var dur;
var len;
var type;

function main(conf) {
  dur = +conf.dur;
  len = +conf.len;
  type = conf.type;
  server();
}


function fail(err, syscall) {
  throw util._errnoException(err, syscall);
}

function server() {
  var serverHandle = new TCP();
  var err = serverHandle.bind('127.0.0.1', PORT);
  if (err)
    fail(err, 'bind');

  err = serverHandle.listen(511);
  if (err)
    fail(err, 'listen');

  serverHandle.onconnection = function(err, clientHandle) {
    if (err)
      fail(err, 'connect');

    // the meat of the benchmark is right here:
    bench.start();
    var bytes = 0;

    setTimeout(function() {
      // report in Gb/sec
      bench.end((bytes * 8) / (1024 * 1024 * 1024));
    }, dur * 1000);

    clientHandle.onread = function(nread, buffer) {
      // we're not expecting to ever get an EOF from the client.
      // just lots of data forever.
      if (nread < 0)
        fail(nread, 'read');

      // don't slice the buffer.  the point of this is to isolate, not
      // simulate real traffic.
      bytes += buffer.length;
    };

    clientHandle.readStart();
  };

  client();
}

function client() {
  var chunk;
  switch (type) {
    case 'buf':
      chunk = new Buffer(len);
      chunk.fill('x');
      break;
    case 'utf':
      chunk = new Array(len / 2 + 1).join('ü');
      break;
    case 'asc':
      chunk = new Array(len + 1).join('x');
      break;
    default:
      throw new Error('invalid type: ' + type);
      break;
  }

  var clientHandle = new TCP();
  var connectReq = {};
  var err = clientHandle.connect(connectReq, '127.0.0.1', PORT);

  if (err)
    fail(err, 'connect');

  clientHandle.readStart();

  connectReq.oncomplete = function(err) {
    if (err)
      fail(err, 'connect');

    while (clientHandle.writeQueueSize === 0)
      write();
  };

  function write() {
    var writeReq = { oncomplete: afterWrite };
    var err;
    switch (type) {
      case 'buf':
        err = clientHandle.writeBuffer(writeReq, chunk);
        break;
      case 'utf':
        err = clientHandle.writeUtf8String(writeReq, chunk);
        break;
      case 'asc':
        err = clientHandle.writeAsciiString(writeReq, chunk);
        break;
    }

    if (err)
      fail(err, 'write');
  }

  function afterWrite(err, handle, req) {
    if (err)
      fail(err, 'write');

    while (clientHandle.writeQueueSize === 0)
      write();
  }
}
