import java.net.*;
import java.io.*;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class Client {

    File file=null;
    public static void main(String[] args) throws IOException
    {
        InetAddress ip = InetAddress.getByName("localhost");
        List<String> user_files = new ArrayList<String>();
        String directory = "C:\\Users\\andrze\\Desktop\\uzytkownik1";

        ExecutorService executors = Executors.newFixedThreadPool(10);
        while (true) {
            String f=File_Handler.check_changes_in_folder(directory,user_files);

            if(!f.equals("new_files_not_found")) {
                Socket socket = new Socket(ip, 1342);

                Runnable task = new Send_File(socket,f,directory);
                executors.execute(task);
            }
        }

    }
}

class File_Handler
{

    static String check_changes_in_folder(String user_directory,List<String>user_files )
    {
        File[] in = new File(user_directory).listFiles();

        for(int i=0;i< in.length;i++)
        {
            String curr_f = in[i].getName();
            if(!user_files.contains(curr_f))
            {
                user_files.add(curr_f);
                return curr_f;
            }
        }
        return "new_files_not_found";
    }


}

class Send_File extends Thread{
    final Socket s;
    final String directory;
    final String f;

    public Send_File(Socket s,String f,String directory)
    {
        this.s = s;
        this.directory= directory;
        this.f=f;
    }

    public void run()
    {
        System.out.println("NEW THREAD"+ Thread.currentThread().getName());
        try {
            BufferedOutputStream bos = new BufferedOutputStream(s.getOutputStream());
            DataOutputStream dos = new DataOutputStream(bos);
            File file = new File(directory + "\\" + f);
            long length = file.length();
            dos.writeLong(length);
            String name = file.getName();
            dos.writeUTF(name);

            FileInputStream fis = new FileInputStream(file);
            BufferedInputStream bis = new BufferedInputStream(fis);
            int theByte = 0;
            while ((theByte = bis.read()) != -1)
            {
                bos.write(theByte);
            }
            bis.close();
        }catch(Exception e) {
            System.out.println(e);
        }
        finally {
            try {
                s.close();
            }catch(Exception f)
            {
                System.out.println(f);
            }
        }

    }

}