How to use the smart-buffer.SmartBuffer function in smart-buffer

sendSocks5CommandRequest() {
        const buff = new smart_buffer_1.SmartBuffer();
        buff.writeUInt8(0x05);
        buff.writeUInt8(constants_1.SocksCommand[this._options.command]);
        buff.writeUInt8(0x00);
        // ipv4, ipv6, domain?
        if (net.isIPv4(this._options.destination.host)) {
            buff.writeUInt8(constants_1.Socks5HostType.IPv4);
            buff.writeBuffer(ip.toBuffer(this._options.destination.host));
        }
        else if (net.isIPv6(this._options.destination.host)) {
            buff.writeUInt8(constants_1.Socks5HostType.IPv6);
            buff.writeBuffer(ip.toBuffer(this._options.destination.host));
        }
        else {
            buff.writeUInt8(constants_1.Socks5HostType.Hostname);
            buff.writeUInt8(this._options.destination.host.length);
            buff.writeString(this._options.destination.host);

sendSocks5InitialHandshake() {
        const buff = new smart_buffer_1.SmartBuffer();
        buff.writeUInt8(0x05);
        // We should only tell the proxy we support user/pass auth if auth info is actually provided.
        // Note: As of Tor v0.3.5.7+, if user/pass auth is an option from the client, by default it will always take priority.
        if (this._options.proxy.userId || this._options.proxy.password) {
            buff.writeUInt8(2);
            buff.writeUInt8(constants_1.Socks5Auth.NoAuth);
            buff.writeUInt8(constants_1.Socks5Auth.UserPass);
        }
        else {
            buff.writeUInt8(1);
            buff.writeUInt8(constants_1.Socks5Auth.NoAuth);
        }
        this._nextRequiredPacketBufferSize =
            constants_1.SOCKS_INCOMING_PACKET_SIZES.Socks5InitialHandshakeResponse;
        this._socket.write(buff.toBuffer());
        this.state = constants_1.SocksClientState.SentInitialHandshake;

let xferBuffer: Buffer;
      let remainingBuffer: SmartBuffer;
      
      if (plainWriteBuffer.length <= this._getAvailableRemoteBufferSize()) {
        // Send the whole buffer in one go.
        xferBuffer = plainWriteBuffer;
        remainingBuffer = new SmartBuffer();
      } else {

        // Cut the buffer into two.
        xferBuffer = Buffer.alloc(this._getAvailableRemoteBufferSize());
        plainWriteBuffer.copy(xferBuffer, 0, 0, this._getAvailableRemoteBufferSize());

        const secondPartBuffer = Buffer.alloc(plainWriteBuffer.length - this._getAvailableRemoteBufferSize());
        plainWriteBuffer.copy(secondPartBuffer, 0, this._getAvailableRemoteBufferSize());
        remainingBuffer = new SmartBuffer();
        remainingBuffer.writeBuffer(secondPartBuffer);
      }

      WebIpc.writeBulkFile(this._fileIdentifier, xferBuffer);

      this._writeBuffer = remainingBuffer;
      this._removeBufferDelta -= xferBuffer.length;

      this._availableSize += xferBuffer.length;
      this._onAvailableSizeChangeEventEmitter.fire(this._availableSize);
    }

    if (this._closePending && this._writeBuffer.length === 0) {
      WebIpc.closeBulkFile(this._fileIdentifier, this._success);
      this._isOpen = false;
      this._closePending = false;

private sendSocks5CommandRequest() {
    const buff = new SmartBuffer();

    buff.writeUInt8(0x05);
    buff.writeUInt8(SocksCommand[this._options.command]);
    buff.writeUInt8(0x00);

    // ipv4, ipv6, domain?
    if (net.isIPv4(this._options.destination.host)) {
      buff.writeUInt8(Socks5HostType.IPv4);
      buff.writeBuffer(ip.toBuffer(this._options.destination.host));
    } else if (net.isIPv6(this._options.destination.host)) {
      buff.writeUInt8(Socks5HostType.IPv6);
      buff.writeBuffer(ip.toBuffer(this._options.destination.host));
    } else {
      buff.writeUInt8(Socks5HostType.Hostname);
      buff.writeUInt8(this._options.destination.host.length);
      buff.writeString(this._options.destination.host);

private sendSocks4InitialHandshake() {
    const userId = this._options.proxy.userId || '';

    const buff = new SmartBuffer();
    buff.writeUInt8(0x04);
    buff.writeUInt8(SocksCommand[this._options.command]);
    buff.writeUInt16BE(this._options.destination.port);

    // Socks 4 (IPv4)
    if (net.isIPv4(this._options.destination.host)) {
      buff.writeBuffer(ip.toBuffer(this._options.destination.host));
      buff.writeStringNT(userId);
      // Socks 4a (hostname)
    } else {
      buff.writeUInt8(0x00);
      buff.writeUInt8(0x00);
      buff.writeUInt8(0x00);
      buff.writeUInt8(0x01);
      buff.writeStringNT(userId);
      buff.writeStringNT(this._options.destination.host);

static createUDPFrame(options) {
        const buff = new smart_buffer_1.SmartBuffer();
        buff.writeUInt16BE(0);
        buff.writeUInt8(options.frameNumber || 0);
        // IPv4/IPv6/Hostname
        if (net.isIPv4(options.remoteHost.host)) {
            buff.writeUInt8(constants_1.Socks5HostType.IPv4);
            buff.writeUInt32BE(ip.toLong(options.remoteHost.host));
        }
        else if (net.isIPv6(options.remoteHost.host)) {
            buff.writeUInt8(constants_1.Socks5HostType.IPv6);
            buff.writeBuffer(ip.toBuffer(options.remoteHost.host));
        }
        else {
            buff.writeUInt8(constants_1.Socks5HostType.Hostname);
            buff.writeUInt8(Buffer.byteLength(options.remoteHost.host));
            buff.writeString(options.remoteHost.host);
        }

private sendSocks5UserPassAuthentication() {
    const userId = this._options.proxy.userId || '';
    const password = this._options.proxy.password || '';

    const buff = new SmartBuffer();
    buff.writeUInt8(0x01);
    buff.writeUInt8(Buffer.byteLength(userId));
    buff.writeString(userId);
    buff.writeUInt8(Buffer.byteLength(password));
    buff.writeString(password);

    this._nextRequiredPacketBufferSize =
      SOCKS_INCOMING_PACKET_SIZES.Socks5UserPassAuthenticationResponse;
    this._socket.write(buff.toBuffer());
    this.state = SocksClientState.SentAuthentication;
  }

public async load(oid: string): Promise {
    const type = shell.exec(`git cat-file -t ${oid}`, { silent: true }).stdout.trim()
    const size = shell.exec(`git cat-file -s ${oid}`, { silent: true }).stdout.trim()
    const data = await git.binaryCatFile([type, oid])

    const raw = new SmartBuffer()
    raw.writeString(`${type} `)
    raw.writeString(size)
    raw.writeUInt8(0)
    raw.writeBuffer(data)

    return this.helper.ipld.deserialize(raw.toBuffer())
  }