'use strict;'

var io = require('socket.io');
var fs = require('fs');
var mysql = require('mysql');
var http = require('http');
var config = require("./config");

function Server() {
	var self = this;
	this.db = mysql.createConnection({
		host: 'localhost',
		user: config.mysql.username,
		password: config.mysql.password,
		database: config.mysql.database,
	});

	this.db.connect(function(err) {
		if(err)
			throw err;
	});

	var self = this;
	this.app = http.createServer(handler);
	this.app.listen(config.port);
	this._socket_io = io.listen(this.app);
	this._socket_io.sockets.on('connection', function(socket) {
		self.connect_cb(socket);
	});
}

Server.prototype.connectionsArray = [];
Server.prototype.pollingTimers = [];
Server.prototype.pollingOptions = [
	{
		query: 'SELECT o.*, top.minutes FROM options o inner join time_option top on top.id=o.id_time where o.finished=0 order by o.id desc',
		notification_name: 'notification2',
		result_name: 'users_this',
		timer: 1000,
	},
	{
		query: 'SELECT * FROM time_option ORDER BY minutes',
		notification_name: 'notification3',
		result_name: 'option',
		timer: 1000,
	},
	{
		query: 'SELECT * FROM rates order by id desc limit 1',
		notification_name: 'notification4',
		result_name: 'rate',
		timer: 1000,
	},
	{
		query: 'SELECT o.*, top.minutes FROM options o inner join time_option top on top.id=o.id_time where o.finished!=0 and  o.end_timestamp >= (UNIX_TIMESTAMP(CURRENT_TIMESTAMP)-86400) order by o.id desc',
		notification_name: 'notification',
		result_name: 'users',
		timer: 1000,
	}
];

function handler(req, res) {
	fs.readFile(__dirname + '/../index.php', function(err, data) {
		if (err) {
			console.log(err);
			res.writeHead(500);
			return res.end('Error loading index.php');
		}
		res.writeHead(200);
		res.end(data);
	});
}

// creating a new websocket to keep the content updated without any AJAX request
Server.prototype.connect_cb = function (socket) {
	var self = this;
	if (!self.connectionsArray.length) {
		self.pollingOptions.forEach(function(options, i) {
			setTimeout(function(i){
				self.pollingLoop(i);
			}, i*100, i)
		});
	}

	socket.on('disconnect', function() {
		var socketIndex = self.connectionsArray.indexOf(socket);
		// console.log('socketID = %s got disconnected', socketIndex);
		if (~socketIndex) {
			self.connectionsArray.splice(socketIndex, 1);
		}
	});
	// console.log('A new socket is connected!');
	self.connectionsArray.push(socket);
	// console.log(self.connectionsArray.length);
};

Server.prototype.pollingLoop = function(option_id) {
	var self = this;
	var options = self.pollingOptions[option_id];
	var query = self.db.query(options.query),
		result = []; // this array will contain the result of our db query

	// if(option_id == 1) console.log('start '+option_id);

	// setting the query listeners
	query.on('error', function(err) {
			// Handle error, and 'end' event will be emitted after this as well
			console.log(err);
			self.updateSockets(option_id, err);
		})
		.on('result', function(row) {
			// it fills our array looping on each user row inside the db
			result.push(row);
		})
		.on('end', function() {
			// loop on itself only if there are sockets still connected
			if (self.connectionsArray.length) {
				self.pollingTimers[option_id] = setTimeout(function() {
					self.pollingLoop(option_id)
				}, options.timer);

				self.updateSockets(option_id, result);
			} else {
				console.log('The server timer was stopped because there are no more socket connections on the app')
			}
		});
};

Server.prototype.updateSockets = function(option_id, result) {
	var self = this;
	var data = {
		time: new Date()
	};
	data[self.pollingOptions[option_id].result_name] = result;

	// sending new data to all the sockets connected
	for (var i in self.connectionsArray) {
		self.connectionsArray[i].volatile.emit(self.pollingOptions[option_id].notification_name, data);
	};
};

module.exports = Server