private ConnectivitySettings proxyToCs(Proxy proxy, URI uri) {
    ConnectivitySettings cs = new ConnectivitySettings();
    InetSocketAddress isa = (InetSocketAddress) proxy.address();
    switch (proxy.type()) {
      case HTTP:
        setupProxy(cs, ConnectivitySettings.CONNECTION_VIA_HTTPS, isa);
        break;
      case SOCKS:
        setupProxy(cs, ConnectivitySettings.CONNECTION_VIA_SOCKS, isa);
        break;
      default:
    }

    String prosyUser = NetworkSettings.getAuthenticationUsername(uri);
    if (prosyUser != null && !prosyUser.isEmpty()) {
      cs.setProxyUsername(prosyUser);
      cs.setProxyPassword(Keyring.read(NetworkSettings.getKeyForAuthenticationPassword(uri)));
    }
    return cs;
  }