node-minecraft-protocol/src/client.js

var EventEmitter = require('events').EventEmitter;
var debug = require('./debug');
var serializer = require('./transforms/serializer');
var compression = require('./transforms/compression');
var framing = require('./transforms/framing');
var crypto = require('crypto');
var states = serializer.states;
var version = require('./version');
var packets = require('minecraft-data')(version.majorVersion).protocol.states;
var readPackets = require("./packets").readPackets;
var packetIndexes = readPackets(packets, states);


class Client extends EventEmitter
{
  packetsToParse={};
  serializer;
  compressor=null;
  framer=framing.createFramer();
  cipher=null;
  decipher=null;
  splitter=framing.createSplitter();
  decompressor=null;
  deserializer;
  isServer;

  constructor(isServer) {
    super();

    this.serializer = serializer.createSerializer({ isServer });
    this.deserializer = serializer.createDeserializer({ isServer, packetsToParse: this.packetsToParse });
    this.isServer = !!isServer;

    this.on('newListener', function(event, listener) {
      var direction = this.isServer ? 'toServer' : 'toClient';
      if(packetIndexes.packetStates[direction].hasOwnProperty(event) || event === "packet") {
        if(typeof this.packetsToParse[event] === "undefined") this.packetsToParse[event] = 1;
        else this.packetsToParse[event] += 1;
      }
    });
    this.on('removeListener', function(event, listener) {
      var direction = this.isServer ? 'toServer' : 'toClient';
      if(packetIndexes.packetStates[direction].hasOwnProperty(event) || event === "packet") {
        this.packetsToParse[event] -= 1;
      }
    });
  }

  get state(){
    return this.serializer.protocolState;
  }

  set state(newProperty) {
    var oldProperty = this.serializer.protocolState;
    this.serializer.protocolState = newProperty;
    this.deserializer.protocolState = newProperty;
    this.emit('state', newProperty, oldProperty);
  }

  get compressionThreshold() {
    return this.compressor == null ? -2 : this.compressor.compressionThreshold;
  }

  set compressionThreshold(threshold) {
    this.setCompressionThreshold(threshold);
  }

  setSocket(socket) {
    var ended = false;

    // TODO : A lot of other things needs to be done.
    var endSocket = () => {
      if(ended) return;
      ended = true;
      this.socket.removeListener('close', endSocket);
      this.socket.removeListener('end', endSocket);
      this.socket.removeListener('timeout', endSocket);
      this.emit('end', this._endReason);
    };

    var onFatalError = (err) => {
      this.emit('error', err);
      endSocket();
    };

    var onError = (err) => this.emit('error', err);

    this.socket = socket;

    if(this.socket.setNoDelay)
      this.socket.setNoDelay(true);

    this.socket.on('connect', () => this.emit('connect'));

    this.socket.on('error', onFatalError);
    this.socket.on('close', endSocket);
    this.socket.on('end', endSocket);
    this.socket.on('timeout', endSocket);
    this.serializer.on('error', onError);
    this.deserializer.on('error', onError);
    this.framer.on('error', onError);
    this.splitter.on('error', onError);

    this.socket.pipe(this.splitter).pipe(this.deserializer);
    this.serializer.pipe(this.framer).pipe(this.socket);

    this.deserializer.on('data', (parsed) => {
      this.emit('packet', parsed.data, parsed.metadata);
      this.emit(parsed.metadata.name, parsed.data, parsed.metadata);
      this.emit('raw.' + parsed.metadata.name, parsed.buffer, parsed.metadata);
      this.emit('raw', parsed.buffer, parsed.metadata);
    });
  }

  end(reason) {
    this._endReason = reason;
    this.socket.end();
  }

  setEncryption(sharedSecret) {
    if (this.cipher != null)
      throw new Error("Set encryption twice !");
    this.cipher = crypto.createCipheriv('aes-128-cfb8', sharedSecret, sharedSecret);
    this.cipher.on('error', (err) => this.emit('error', err));
    this.framer.unpipe(this.socket);
    this.framer.pipe(this.cipher).pipe(this.socket);
    this.decipher = crypto.createDecipheriv('aes-128-cfb8', sharedSecret, sharedSecret);
    this.decipher.on('error', (err) => this.emit('error', err));
    this.socket.unpipe(this.splitter);
    this.socket.pipe(this.decipher).pipe(this.splitter);
  }

  setCompressionThreshold(threshold) {
    if (this.compressor == null) {
      this.compressor = compression.createCompressor(threshold);
      this.compressor.on('error', (err) => this.emit('error', err));
      this.serializer.unpipe(this.framer);
      this.serializer.pipe(this.compressor).pipe(this.framer);
      this.decompressor = compression.createDecompressor(threshold);
      this.decompressor.on('error', (err) => this.emit('error', err));
      this.splitter.unpipe(this.deserializer);
      this.splitter.pipe(this.decompressor).pipe(this.deserializer);
    } else {
      this.decompressor.threshold = threshold;
      this.compressor.threshold = threshold;
    }
  }

  write(packetName, params) {
    debug("writing packet " + this.state + "." + packetName);
    debug(params);
    this.serializer.write({ packetName, params });
  }

  writeRaw(buffer) {
    if (this.compressor === null)
      this.framer.write(buffer);
    else
      this.compressor.write(buffer);
  }
}

module.exports = Client;