const express = require('express');
const app = express();
const session = require('express-session');
const http = require('http').Server(app);
const io = require('socket.io')(http);
const crypto = require('crypto');
const ChatSingleton = require('./chat');

const Chat = ChatSingleton.instance;


let connect_sid = Date.now();

app.use(session({
    secret: 'keyboard cat',
    resave: true,
    saveUninitialized: true,
    cookie: { secure: false }
}));

app.get('/', function (req, res) {
    console.log(new Date().getTime() + ":[get: /]");
    
    //connect_sid = req.sessionID;
    console.log('connect_sid', connect_sid);
    
    res.sendFile(__dirname + '/public/index.html');
});

app.get('/customer', (req, res) => {
    console.log(new Date().getTime() + ":[get: /customer]");
    
    //connect_sid = req.sessionID;
    console.log('connect_sid', connect_sid);
    
    res.sendFile(__dirname + '/public/customer.html');
});

app.get('/operator', (req, res) => {
    console.log(new Date().getTime() + ":[get: /]");
    
    //connect_sid = req.sessionID;
    console.log('connect_sid', connect_sid);
    
    res.sendFile(__dirname + '/public/operator.html');
});

app.use(express.static('public'));

http.listen(3001, function () {
    console.log('listening on *:3001');
});


io.on('connection', (socket) => {
    
    const EVENTS = Chat.EVENTS;
    const ERRORS = Chat.ERRORS;
    const ROLES = Chat.ROLES;
    const DEFAULT_ROOMS = Chat.DEFAULT_ROOMS;
    let event = '';
    let user = undefined;
    
    
    // create user and send updates
    socket.on(EVENTS.CONNECTION.OPEN, (data) => {
        console.log('CONNECTION:OPEN', JSON.stringify(data));
        
        // create new user
        const buf = crypto.randomBytes(32);
        const uniqID = buf.toString('hex');
        user = Chat.createUser(data.name, data.role, uniqID, socket);

        console.log('user', user);

        // join user own room
        socket.join(user.room);

        // notify user is ready
        event = Chat.event(EVENTS.ROOM.CREATED, Chat.getUser(user.room));
        io.to(user.room).emit(event.type, event.data);

        // join operators room if role is operator
        if (user.role === ROLES.OPERATOR) {
            socket.join(DEFAULT_ROOMS.OPERATORS);
        }

        // send customers updated list to operators
        event = Chat.event(EVENTS.CUSTOMERS.LIST.UPDATE, Chat.getUsersByRole(ROLES.CUSTOMER));
        io.to(DEFAULT_ROOMS.OPERATORS).emit(event.type, event.data);

        // send operators updated list to operators
        event = Chat.event(EVENTS.OPERATORS.LIST.UPDATE, Chat.getUsersByRole(ROLES.OPERATOR));
        io.to(DEFAULT_ROOMS.OPERATORS).emit(event.type, event.data);

        // send rooms updated list to operators
        event = Chat.event(EVENTS.ROOMS.LIST.UPDATE, Chat.rooms);
        io.to(DEFAULT_ROOMS.OPERATORS).emit(event.type, event.data);
    });


    // operator joins customer's room
    socket.on(EVENTS.ROOM.JOIN, (data) => {
        if (!user) {
            return
        }
        
        const hostRoom = Chat.joinRoom(data.user, user);

        socket.join(hostRoom);
        
        event = Chat.event(EVENTS.ROOM.JOIN, user);
        io.to(hostRoom).emit(event.type, event.data);

        console.log('join room', user.name, event.data);
    });


    // send message
    socket.on(EVENTS.SEND.MESSAGE, (data) => {
        if (!user) {
            return
        }
        
        const room = user.role === ROLES.CUSTOMER ? user.room : data.room;

        Chat.message(data, room, user)
        .then(message => {
            event = Chat.event(EVENTS.SEND.MESSAGE, message);
            io.to(room).emit(event.type, event.data);
    
            console.log('sendMessage', event);
        });
    });


    // leave the room
    socket.on(EVENTS.ROOM.LEAVE, (data) => {
        if (!user) {
            return
        }

        const host = data && data.user || user;
        const promises = Chat.leaveRoom(host, user);

        Promise.all(promises).then(guestSockets => {            
            socket.leave(host.room);

            event = Chat.event(EVENTS.ROOM.LEAVE, user);
            io.to(host.room).emit(event.type, event.data);

            guestSockets.forEach(guestSocket => {
                guestSocket.leave(host.room);
            });
        });
    });


    socket.on('disconnect', () => {
        console.log('disconnect', user);
        
        if (!user) {
            return
        }

        event = Chat.event(EVENTS.CONNECTION.CLOSE);
        io.to(user.room).emit(event.type, event.data);
        
        const promises = Chat.deleteUser(user);
        
        Promise.all(promises).then(guestSockets => {            
            event = Chat.event(EVENTS.ROOM.LEAVE, user);
            io.to(user.room).emit(event.type, event.data);
            
            guestSockets.forEach(guestSocket => {
                guestSocket.leave(user.room);
            });
        });

        const userRole = user.role;

        // send operators updated list to operators
        if (userRole === ROLES.OPERATOR) {
            event = Chat.event(EVENTS.OPERATORS.LIST.UPDATE, Chat.getUsersByRole(ROLES.OPERATOR));
            io.to(DEFAULT_ROOMS.OPERATORS).emit(event.type, event.data);
        }

        // send customers updated list to operators
        if (userRole === ROLES.CUSTOMER) {
            event = Chat.event(EVENTS.CUSTOMERS.LIST.UPDATE, Chat.getUsersByRole(ROLES.CUSTOMER));
            io.to(DEFAULT_ROOMS.OPERATORS).emit(event.type, event.data);
        }
    });
});