package server;

import java.net.Socket;

import java.io.InputStreamReader;

import java.io.OutputStreamWriter;

import java.io.BufferedReader;

import java.io.PrintWriter;

import java.nio.charset.StandardCharsets;

import java.util.Arrays;

import java.util.List;

import server.chatlog;

public class ChatServerThread extends Thread{

private String alias = null;

private Socket sock = null;

List<PrintWriter> listwriter = null;

public ChatServerThread(List<PrintWriter> listwriter, Socket sock){

this.sock = sock;

this.listwriter = listwriter;

}

public void run() {

try{

//Creating a reader and writer for socket's input and output streams

BufferedReader buffreader = new BufferedReader(new InputStreamReader(sock.getInputStream()));

PrintWriter printwriter = new PrintWriter(new OutputStreamWriter(sock.getOutputStream(), StandardCharsets.UTF_8));

while(true){

// rendering request from buffer, 3 different paths QUIT,JOIN,MESSAGE

String request = buffreader.readLine();

if(request == null){

quit(printwriter);

chatlog.out("Client disconnected");

break;

}

chatlog.out(request);

String[] token = request.split(":");

if("join".equals(token[0])){

String joinedstring = String.join("", Arrays.copyOfRange(token, 1, token.length));

join(joinedstring,printwriter);

}

else if ("message".equals(token[0])){

String joinedstring = String.join("", Arrays.copyOfRange(token, 1, token.length));

message(joinedstring);

}

else if("quit".equals(token[0])){

quit(printwriter);

}

}

}

catch(Exception e){

chatlog.out(this.alias + "quit");

}

}

// QUIT: remove writer from list and broadcast client quit

private void quit(PrintWriter writer){

removeWriter(writer);

String msg = this.alias + "quit";

broadcast(msg);

}

private void removeWriter(PrintWriter writer){

synchronized(listwriter){

listwriter.remove(writer);

}

}

// JOIN: Broadcast user joined and add user to list of Printwriter

private void join(String alias, PrintWriter writer){

this.alias = alias;

String msg = alias +"joined";

broadcast(msg);

addwriter(writer);

}

private void message(String msg){

broadcast(this.alias +":" +msg);

}

// addwriter: mutex lock on list to add writer

private void addwriter(PrintWriter writer){

synchronized(listwriter){

listwriter.add(writer);

}

}

// broadcast: thread takes control of list and updates

private void broadcast(String msg){

synchronized(listwriter){

for(PrintWriter writer : listwriter){

writer.println(msg);

writer.flush();

}

}

}

}