OmarElGabry/chat.io

'use strict';

var roomModel   = require('../database').models.room;
var User         = require('../models/user');

var create = function (data, callback){
    var newRoom = new roomModel(data);
    newRoom.save(callback);
};

var find = function (data, callback){
    roomModel.find(data, callback);
}

var findOne = function (data, callback){
    roomModel.findOne(data, callback);
}

var findById = function (id, callback){
    roomModel.findById(id, callback);
}

var findByIdAndUpdate = function(id, data, callback){
    roomModel.findByIdAndUpdate(id, data, { new: true }, callback);
}

/**
 * Add a user along with the corresponding socket to the passed room
 *
 */
var addUser = function(room, socket, callback){
    
    // Get current user's id
    var userId = socket.request.session.passport.user;

    // Push a new connection object(i.e. {userId + socketId})
    var conn = { userId: userId, socketId: socket.id};
    room.connections.push(conn);
    room.save(callback);
}

/**
 * Get all users in a room
 *
 */
var getUsers = function(room, socket, callback){

    var users = [], vis = {}, cunt = 0;
    var userId = socket.request.session.passport.user;

    // Loop on room's connections, Then:
    room.connections.forEach(function(conn){

        // 1. Count the number of connections of the current user(using one or more sockets) to the passed room.
        if(conn.userId === userId){
            cunt++;
        }

        // 2. Create an array(i.e. users) contains unique users' ids
        if(!vis[conn.userId]){
            users.push(conn.userId);
        }
        vis[conn.userId] = true;
    });

    // Loop on each user id, Then:
    // Get the user object by id, and assign it to users array.
    // So, users array will hold users' objects instead of ids.
    var loadedUsers = 0;        
    users.forEach(function(userId, i){
        User.findById(userId, function(err, user){
            if (err) { return callback(err); }
            users[i] = user;

            // fire callback when all users are loaded (async) from database 
            if(++loadedUsers === users.length){
                return callback(null, users, cunt);
            }
        });
    });
}

/**
 * Remove a user along with the corresponding socket from a room
 *
 */
var removeUser = function(socket, callback){

    // Get current user's id
    var userId = socket.request.session.passport.user;

    find(function(err, rooms){
        if(err) { return callback(err); }

        // Loop on each room, Then:
        rooms.every(function(room){
            var pass = true, cunt = 0, target = 0;

            // For every room, 
            // 1. Count the number of connections of the current user(using one or more sockets).
            room.connections.forEach(function(conn, i){
                if(conn.userId === userId){
                    cunt++;
                }
                if(conn.socketId === socket.id){
                    pass = false, target = i;
                }
            });

            // 2. Check if the current room has the disconnected socket, 
            // If so, then, remove the current connection object, and terminate the loop.
            if(!pass) {
                room.connections.id(room.connections[target]._id).remove();
                room.save(function(err){
                    callback(err, room, userId, cunt);
                });
            }

            return pass;
        });
    });
}

module.exports = { 
    create, 
    find, 
    findOne, 
    findById, 
    addUser, 
    getUsers, 
    removeUser 
};