text: //      
  
  const { EventEmitter } = require('events');
  const WS = require('ws');
  
  const {
    encode,
    decode,
    Credentials,
    CredentialsResponse,
    PeerRequest,
    PeerResponse,
    Unpeer,
  } = require('@bunchtogether/braid-messagepack');
  
  class CloseError extends Error {
                         
    constructor(message       ) {
      super(message);
      this.name = 'CloseError';
      this.code = 502;
    }
  }
  
  class PeerError extends Error {
                         
                                  
    constructor(message       , code       , peerId         ) {
      super(message);
      this.name = 'PeerError';
      this.code = code;
      this.peerId = peerId;
    }
  }
  
  class CredentialsError extends Error {
                         
    constructor(message       , code       ) {
      super(message);
      this.name = 'CredentialsError';
      this.code = code;
    }
  }
  
  class PeerConnection extends EventEmitter {
    constructor(id        , address       , maxPayloadLength        , credentials         = {}) {
      super();
      this.id = id;
      this.address = address;
      this.maxPayloadLength = maxPayloadLength;
      this.credentials = credentials;
      this.timeoutDuration = 5000;
    }
  
    async open() {
      let heartbeatInterval;
  
      const ws = new WS(this.address, {
        maxPayload: this.maxPayloadLength,
      });
  
      ws.on('error', () => {
        this.emit('error', new Error(`Websocket error when connecting to ${this.address}, check the 'close' event for additional details`));
      });
  
      ws.on('open', () => {
        this.emit('open');
        this.ws = ws;
        heartbeatInterval = setInterval(() => {
          if (ws.readyState === 1) {
            ws.send(new Uint8Array([0]));
          }
        }, 5000);
      });
  
      ws.on('close', (code        , reason       ) => {
        delete this.ws;
        this.emit('close', code, reason);
        clearInterval(heartbeatInterval);
      });
  
      ws.on('message', (data) => {
        const message = decode(data);
        if (message instanceof CredentialsResponse) {
          this.emit('credentialsResponse', message.value.success, message.value.code, message.value.message);
        } else if (message instanceof PeerResponse) {
          this.emit('peerResponse', message.value.id, message.value.success, message.value.code, message.value.message);
        } else {
          this.emit('message', message);
        }
      });
  
      await new Promise((resolve, reject) => {
        const onOpen = () => {
          this.removeListener('error', onError);
          resolve();
        };
        const onError = (error       ) => {
          this.removeListener('open', onOpen);
          reject(error);
        };
        this.once('error', onError);
        this.once('open', onOpen);
      });
      if (this.credentials) {
        await this.sendCredentials(this.credentials);
      }
      const peerId = await this.sendPeerRequest();
      return peerId;
    }
  
    async close(code         , reason         ) {
      if (!this.ws) {
        throw new Error('Unable to close, socket does not exist');
      }
      await new Promise((resolve, reject) => {
        const onClose = () => {
          this.removeListener('error', onError);
          resolve();
        };
        const onError = (error       ) => {
          this.removeListener('close', onClose);
          reject(error);
        };
        this.once('error', onError);
        this.once('close', onClose);
        this.ws.close(code, reason);
      });
    }
  
    async sendCredentials(credentials        ) {
      if (!this.ws) {
        throw new Error('Unable to send credentials, not open');
      }
      await new Promise((resolve, reject) => {
        const handleClose = () => {
          clearTimeout(timeout);
          this.removeListener('close', handleClose);
          this.removeListener('credentialsResponse', handleCredentialsResponse);
          reject(new CloseError('Connection closed before credentials response was received'));
        };
        const handleCredentialsResponse = (success, code, message) => {
          clearTimeout(timeout);
          this.removeListener('close', handleClose);
          this.removeListener('credentialsResponse', handleCredentialsResponse);
          if (success) {
            resolve();
          } else {
            reject(new CredentialsError(message, code));
          }
        };
        const timeout = setTimeout(() => {
          this.removeListener('credentialsResponse', handleCredentialsResponse);
          reject(new CredentialsError(`Credentials response timeout after ${Math.round(this.timeoutDuration / 100) / 10} seconds`, 504));
        }, this.timeoutDuration);
        this.on('close', handleClose);
        this.on('credentialsResponse', handleCredentialsResponse);
        this.ws.send(encode(new Credentials(credentials)));
      });
    }
  
    sendPeerRequest()                 {
      if (!this.ws) {
        throw new Error('Unable to peer, not open');
      }
      return new Promise((resolve, reject) => {
        const handleClose = () => {
          clearTimeout(timeout);
          this.removeListener('close', handleClose);
          this.removeListener('peerResponse', handlePeerResponse);
          reject(new CloseError('Connection closed before peer response was received'));
        };
        const handlePeerResponse = (id, success, code, message) => {
          clearTimeout(timeout);
          this.removeListener('close', handleClose);
          this.removeListener('peerResponse', handlePeerResponse);
          if (success) {
            resolve(id);
          } else {
            reject(new PeerError(message, code, id));
          }
        };
        const timeout = setTimeout(() => {
          this.removeListener('peerResponse', handlePeerResponse);
          reject(new PeerError(`Peer response timeout after ${Math.round(this.timeoutDuration / 100) / 10} seconds`, 504));
        }, this.timeoutDuration);
        this.on('close', handleClose);
        this.on('peerResponse', handlePeerResponse);
        this.ws.send(encode(new PeerRequest(this.id)));
      });
    }
  
    unpeer() {
      if (!this.ws) {
        throw new Error('Unable to unpeer, not open');
      }
      this.ws.send(encode(new Unpeer()));
    }
  
                      
                           
                                     
                                
                   
                                    
  }
  
  module.exports = PeerConnection;
  