package com.coder.client;

import java.io.IOException;
import java.util.HashSet;
import java.util.logging.Level;
import java.util.logging.Logger;

import zutil.log.LogUtil;

import com.coder.client.session.ProjectMessageListener;
import com.coder.client.session.Session;
import com.coder.client.session.SessionEventHandler;
import com.coder.server.message.CoderMessage;

public class SessionHandler{
	public static final Logger logger = LogUtil.getLogger();
	private static SessionHandler instance = null;

	private Session session;
	private HashSet<SessionEventHandler> sessionEventHandlers = new HashSet<SessionEventHandler>();
	private HashSet<ProjectMessageListener> messageListeners = new HashSet<ProjectMessageListener>();
	
	private SessionHandler(){
		
	}
	
	public static SessionHandler getInstance(){
		if(instance == null){
			instance = new SessionHandler();
		}
		return instance;
	}
	
	public boolean setupConnection(String url, int port){
		if(session != null && session.isConnected()){
			session.close();
		}
		session = Session.setupConnection(url, port);
		if(session != null){
			for(ProjectMessageListener listener : messageListeners){
				session.addMessageListener(listener);
			}
			for(SessionEventHandler eventHandler : sessionEventHandlers){
				eventHandler.sessionConnectionSuccess();
			}
			return true;
		}else{
			for(SessionEventHandler eventHandler : sessionEventHandlers){
				eventHandler.sessionConnectionFailure();
			}
			return false;
		}
	}
	
	public boolean authenticateSession(String username, char[] clearTextPassword){
		if(session == null){
			return false;
		}else{
			boolean success = session.authenticate(username, clearTextPassword); 
			if(success){
				for(SessionEventHandler eventHandler : sessionEventHandlers){
					eventHandler.sessionAuthenticationSuccess();
				}
				session.start();
				return true;
			}else{
				for(SessionEventHandler eventHandler : sessionEventHandlers){
					eventHandler.sessionAuthenticationFailure();
				}
				return false;
			}
		}
	}
	
	public boolean sendMessage(CoderMessage msg){
		logger.fine("sending a message");
		if(session != null){
			try {
				session.send(msg);
			} catch (IOException e) {
				logger.log(Level.SEVERE, "unable to send message", e);
				closeCurrentSession(true);
				return false;
			}
			logger.fine("successfully sent the meessage");
			return true;
		}
		return false;
	}
	
	public void closeCurrentSession(boolean retry){
		if(session != null){
			logger.info("closing session to server");
			session.close();
			session = null;
			for(SessionEventHandler eventHandler : sessionEventHandlers){
				eventHandler.sessionDisconnected(retry);
			}
		}else{
			logger.fine("cannot close current session: session already terminated");
		}
	}
	
	public void addSessionEventHandler(SessionEventHandler eventHandler){
		this.sessionEventHandlers.add(eventHandler);
	}

	public void addMessageListener(ProjectMessageListener listener) {
		messageListeners.add(listener);
		if(session != null){
			session.addMessageListener(listener);
		}
	}

	public void triggerAuthenticationCancel() {
		if(session.isConnected() && !session.isAuthenticated()){
			closeCurrentSession(false);
			for(SessionEventHandler eventHandler : sessionEventHandlers){
				eventHandler.sessionAuthenticationCancel();
			}
		}else{
			logger.warning("Can only cancel a connected but not yet authenticated authentication. ignoring call");
		}
	}
	
}