// Flags: --no-warnings
'use strict';

// Tests that stream data is successfully transmitted under
// packet loss conditions on the transmitting end.

const common = require('../common');
if (!common.hasQuic)
  common.skip('missing quic');

common.skip('temporarily skip packetloss tests for refactoring');

const Countdown = require('../common/countdown');
const assert = require('assert');
const {
  key,
  cert,
  ca,
  debug
} = require('../common/quic');
const { once } = require('events');
const { pipeline } = require('stream');

const { createQuicSocket } = require('net');

const kData = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
const options = { key, cert, ca, alpn: 'echo' };

const client = createQuicSocket({ client: options });
const server = createQuicSocket({ server: options });

// Both client and server will drop received packets about 20% of the time
// It is important to keep in mind that this will make the runtime of the
// test non-deterministic. If we encounter flaky timeouts with this test,
// the randomized packet loss will be the reason, but random packet loss
// is exactly what is being tested. So if flaky timeouts do occur, it will
// be best to extend the failure timeout for this test.
server.setDiagnosticPacketLoss({ tx: 0.2 });
client.setDiagnosticPacketLoss({ tx: 0.2 });

const countdown = new Countdown(1, () => {
  debug('Countdown expired. Destroying sockets');
  server.close();
  client.close();
});

(async function() {
  server.on('session', common.mustCall((session) => {
    debug('QuicServerSession Created');
    session.on('stream', common.mustCall((stream) => {
      debug('Bidirectional, Client-initiated stream %d received', stream.id);
      pipeline(stream, stream, common.mustSucceed());
    }));
  }));

  await server.listen();

  debug('Server is listening on port %d', server.endpoints[0].address.port);

  const req = await client.connect({
    address: common.localhostIPv4,
    port: server.endpoints[0].address.port,
  });

  const stream = await req.openStream();

  let n = 0;
  // This forces multiple stream packets to be sent out
  // rather than all the data being written in a single
  // packet.
  function sendChunk() {
    if (n < kData.length) {
      stream.write(kData[n++], common.mustCall());
      setImmediate(sendChunk);
    } else {
      stream.end();
    }
  }
  sendChunk();

  let data = '';
  stream.resume();
  stream.setEncoding('utf8');
  stream.on('data', (chunk) => data += chunk);
  stream.on('end', common.mustCall(() => {
    debug('Received data: %s', kData);
    assert.strictEqual(data, kData);
  }));

  stream.on('close', common.mustCall(() => {
    countdown.dec();
  }));

  await Promise.all([
    once(server, 'close'),
    once(client, 'close')
  ]);
})().then(common.mustCall());