package QQ;
import java.io.*;
import java.net.*;
import java.util.*;
public class QQServer {
	
	public static void main(String[] args){
		ServerSocket ss=null;
		Socket sock=null;
		ArrayList al=new ArrayList();
		try{
			ss=new ServerSocket(1228);
			while(true){
				sock=ss.accept();
				Server ser=new Server(al,sock);
				Thread t=new Thread(ser);
				al.add(ser);
				t.start();
			}
		}
		catch (Exception e){e.printStackTrace();}
		finally{
			if (ss!=null){
				try{ ss.close(); } catch(IOException e){e.printStackTrace();}  
          	}
        }
	}
}

class Server implements Runnable{
	public ObjectInputStream in=null;
	public ObjectOutputStream out=null;
	private Socket s;
	private ArrayList al;
	private String name;
	
	public Server(ArrayList al,Socket s){	
		this.al=al;
		this.s=s;
	}
	
	public void setName(String s){
		this.name=s;
	}
	public String getName(){
		return this.name;
	}
	
	public void run(){
		try{
			out=new ObjectOutputStream(this.s.getOutputStream());
			in=new ObjectInputStream(this.s.getInputStream());
			while(true){
				if (s.isClosed()) {
					 break;
				}
				else{
					Object o=in.readObject();
					if (o==null) continue;
					ServerInfo si=(ServerInfo)o;
					int type=si.getType();
					if (si.getUser().equals("All") || type==ServerInfo.ADD || type==ServerInfo.DEL)
					{
						
						notiAll(si);
					}	
					else noti(si);
					
					if (type==ServerInfo.DEL){
						s.close();
						this.al.remove(this);
						break;
					}	
														
					if (type==ServerInfo.ADD){
						Iterator it=al.iterator();
						while(it.hasNext()){
							Server ms=(Server)it.next();
							String name=ms.getName();
							ServerInfo si2=new ServerInfo(name+" entered!",name,ServerInfo.ADD);
							out.writeObject(si2);
							out.flush();
						} 						
					}					


				} //end else
			} //end while
		} //end try
		catch(Exception e){e.printStackTrace();}
		finally{
			if(s!=null) {
				try {s.close();}catch(Exception ex) {ex.printStackTrace();} 
        	}
			if(in!=null) {
				try {in.close();}catch(Exception ex) {ex.printStackTrace();} 
        	}
			if(out!=null) {
				try {out.close();}catch(Exception ex) {ex.printStackTrace();} 
        	}    
        }
    }
    
    public ObjectOutputStream getWriter(){
    	return this.out;
    }
    
    private void notiAll(ServerInfo si) throws Exception{
    	String content=si.getContent();
    	if (si.getUser().equals("All")){
    		String c=si.getContent();
    		c=name+" said: "+c;
    		si.setContent(c);
    	}
    	if (si.getType()==ServerInfo.ADD) this.setName(si.getUser());
    	
		Iterator it=al.iterator();
		while(it.hasNext()){
			Server ms=(Server)it.next();
			if (!(si.getUser().equals(ms.getName()))){
				ObjectOutputStream pw=ms.getWriter();
				pw.writeObject(si);
				pw.flush();
			}
		}  //end while
    }
    
    private void noti(ServerInfo si) throws Exception{
    	String user=si.getUser();
    	String content=si.getContent();
 		Iterator it=al.iterator();
		while(it.hasNext()){
			Server ms=(Server)it.next();
			if (ms.getName().equals(user)){
				String c=si.getContent();
				c=name+"  said: "+c;
				si.setContent(c);
				ObjectOutputStream pw=ms.getWriter();
				pw.writeObject(si);
				pw.flush();
			}
		}    	
    	
    }
}