/*
    * junixsocket
    *
    * Copyright 2009-2024 Christian Kohlschütter
    *
    * Licensed under the Apache License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.newsclub.net.unix.selftest.apps;
  
  import java.io.File;
  import java.io.FileInputStream;
  import java.io.IOException;
  import java.nio.ByteBuffer;
  import java.nio.channels.ClosedChannelException;
  import java.nio.channels.SocketChannel;
  import java.util.concurrent.ExecutionException;
  
  import org.newsclub.net.unix.AFAddressFamily;
  import org.newsclub.net.unix.AFOutputStream;
  import org.newsclub.net.unix.AFSocket;
  import org.newsclub.net.unix.AFSocketAddress;
  import org.newsclub.net.unix.server.AFSocketServer;
  
  public class ZeroServer {
    private static void printHelp() {
      System.err.println("Syntax: java " + ZeroServer.class.getName() + " <URI>");
      System.err.println();
      System.err.println("Supported schemes: " + AFAddressFamily.uriSchemes());
    }
  
    public static void main(String[] args) throws IOException, InterruptedException,
        ExecutionException {
      if (args.length == 0) {
        printHelp();
        System.exit(1);
        return;
      }
  
      AFSocketAddress address;
      try {
        address = SocketAddressUtil.parseAddress(args[0]);
      } catch (Exception e) {
        printHelp();
        System.err.println();
        e.printStackTrace();
        System.exit(1);
        return;
      }
  
      new AFSocketServer<AFSocketAddress>(address) {
        @Override
        protected void doServeSocket(AFSocket<?> sock) throws IOException {
          System.out.println("Connected: " + sock);
          long numBytes = -1;
          try {
  
            File devZeroFile = new File("/dev/zero");
            if (devZeroFile.exists() && Boolean.parseBoolean(System.getProperty("useDevZero",
                "true"))) {
              System.out.println("Streaming /dev/zero");
              try (FileInputStream fin = new FileInputStream(devZeroFile);
                  AFOutputStream out = sock.getOutputStream()) {
                numBytes = out.transferFrom(fin); // NOPMD
              }
            } else {
              System.out.println("Streaming empty ByteBuffer");
              ByteBuffer buf = ByteBuffer.allocate(8192);
              sock.setSendBufferSize(8192);
              sock.setSoTimeout(1);
              numBytes = 0;
              try (SocketChannel out = sock.getChannel()) {
                while (!Thread.interrupted()) {
                  numBytes += out.write(buf);
                  buf.rewind();
                }
              } catch (ClosedChannelException e) {
                // ignore
              }
            }
          } finally {
            System.out.println("Disconnected: " + sock + "; written bytes: " + (numBytes == -1
                ? "unknown" : numBytes));
          }
        }
      }.startAndWaitToBecomeReady();
      System.out.println("Server ready, listening on " + address);
    }
  }