/**
  * Brogaming server
  * http://brogaming.ru
  */

import java.io.*;
import java.lang.reflect.InvocationTargetException;
import java.net.*;
import java.security.MessageDigest;
import java.util.Properties;

public class BrogamingServer extends Thread{

	Socket s;
	int num;
	
	public BrogamingServer(int num, Socket s) {
		// copy data
		this.num = num;
		this.s = s;
		
		// and run new stream (look function run())
		setDaemon(true);
		setPriority(NORM_PRIORITY);
		start();
	}
	
	public static void main(String args[]) {
		try {
			int i = 0; // счетчик подключений
		
			// create socket on 3128 port
			ServerSocket server = new ServerSocket(3128);//, 0, InetAddress.getByName("192.168.1.9"));
		
			System.out.println("server is started");
		
			// listening port
			while(true) {
				new BrogamingServer(i, server.accept());
				i++;
			}
		}catch(Exception e){System.out.println("init error: " + e);}
	}
	
	
	
	public void run() {
		try {
			Thread t = new Thread(new Runnable() {
				@Override
				public void run() {
					System.out.println("client connected");
					RecieveDataFromClient();
				}
			});
			t.setDaemon(true);
			t.start();
		}catch(Exception e){System.out.println("init error: " + e);}
	}
	
	private void RecieveDataFromClient() {
		try {
			InputStream is = s.getInputStream();
			OutputStream os = s.getOutputStream();
			
			startConnection(is, os);
			
			while(s.isConnected())
			{
				
				
				byte buf[] = new byte[64*1024];
				int r = is.read(buf);
				
				if (buf.length == 0 || r == 0)
				{
					os.write(new String("Buffer is empty").getBytes());
					continue;
				}
				
				// create String with received data from client
				String data = new String(buf, 0, r); //"UTF-8");
				
				if (data == null || data.isEmpty())
				{
					os.write(new String("Recieved data is empty").getBytes());
					continue;
				}
				System.out.println("Recieved Data: " + data);
				os.write(new String("pong").getBytes());
				os.flush();	
			}
		}
		catch(Exception e) {System.out.println("RecieveDataFromClient: " + e);}
	}
	
	private void startConnection(InputStream is, OutputStream os) {
		try {
			String ss;
			readLine(is); // first line, ignore it for now
			Properties props = new Properties();
			while((ss=readLine(is))!=null && !ss.equals(""))
			{
				String[] q = ss.split(": ");
				props.put(q[0], q[1]);
			}
			String key = (String) props.get("Sec-WebSocket-Key");
			String r = key + "" + "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"; // append "magic" key to it
			
			MessageDigest md = MessageDigest.getInstance("SHA-1");
		    md.update(r.getBytes("iso-8859-1"), 0, r.length());
		    byte[] sha1hash = md.digest();

		    String returnBase = base64(sha1hash);
			
			String ret = "HTTP/1.1 101 Switching Protocols\r\n";
				ret+="Upgrade: websocket\r\n";
				ret+="Connection: Upgrade\r\n";
				ret+="Sec-WebSocket-Accept: "+returnBase+"\r\n";
				ret+="\r\n";
			os.write(ret.getBytes());
			os.flush();
		}catch(Exception e){System.out.println("start connection error: " + e);}
		
	}

	private String base64(byte[] input) throws ClassNotFoundException, SecurityException, NoSuchMethodException, IllegalArgumentException, IllegalAccessException, InvocationTargetException, InstantiationException
	{
	    Class<?> c = Class.forName("sun.misc.BASE64Encoder");
		java.lang.reflect.Method m = c.getMethod("encode", new Class<?>[]{byte[].class});
		String s = (String) m.invoke(c.newInstance(), input);
		return s;
	}
	
	private String readLine(InputStream in) {
		try {
			String line = "";
			int pread;
			int read = 0;
			while(true)
			{
				pread = read;
				read = in.read();
				if(read!=13&&read!=10)
					line += (char) read;
				if(pread==13&&read==10) break;
			}
			return line;
		}catch(IOException ex){}
		return null;
	}

}