// init
var methods = {};

/**
 * start web server
 * @author Ruben Meyer
 * @return {Void}
 */
methods.start = () => {
	// init express framework
	let express = require('express');
	let session_handler = require('express-session');

	// utilities
	let fs = require('fs');
	let path = require('path');
	let mime = require('mime-types');

	// app variable
	let app = express();
	app.set('view engine', 'pug'); // page engine
	app.set('views', global['__dirname']+'/bin/web');

	let bp = require('body-parser'); // POST Body parser
	let cp = require('cookie-parser'); // Cookie handler

	// Access Control Headers
	app.use( (req, res, next) => {
		res.set({
			'X-Powered-By': global['gds'].cfg
		});
		res.header("Access-Control-Allow-Origin", "*");
		res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
		next();
	});

	// BodyParser & CookieParser
	app.use(bp.json());
	app.use(bp.urlencoded({
		extended: true
	}));
	app.use(cp(global['gds'].cfg.web.cookieKey));

	// Pretty print
	app.locals.pretty = true;

	// Sessions
	session_options = {
		secret: global['gds'].cfg.web.sessionKey,
		resave: false,
		saveUninitialized: false, cookie: {}};
	if(app.get('env') === 'production') {
		session_options.cookie.secure = true;
	}
	app.use(session_handler(session_options));

	//static files
	app.use('/res', (req, res, next) => {
		if(typeof global['gds'].cache.web == 'undefined') global['gds'].cache.web = {};

		let dir = global['__dirname'] + '/res/web';


		if(!req.session || !req.session.user) dir += '/auth';
		else dir += '/app';

		let joined_path = path.join(dir, /^[^?]+/.exec(req.url)[0]);

		// path already cached; not exist
		if(global['gds'].cache.web[joined_path] == false) {
			res.status(404).end();
		// path already cached; exist
		} else if(global['gds'].cache.web[joined_path] == true){
			let contentType = mime.contentType(path.extname(joined_path));
			res.setHeader('Content-Type', contentType);
			fs.createReadStream(joined_path).pipe(res);
		// check path
		} else {
			fs.exists(joined_path, (exists) => {
				global['gds'].cache.web[joined_path] = exists;
				if(exists) {
					let contentType = mime.contentType(path.extname(joined_path));
					res.setHeader('Content-Type', contentType);

					fs.createReadStream(joined_path).pipe(res);
				} else {
					res.status(404).end();
				}
			});
		}
	});

	// web routes
	app.use('/auth', require(global['__dirname']+'/bin/web/auth/routes/main'));
	app.use('/',     require(global['__dirname']+'/bin/web/app/routes/main'));

	// start server
	app.listen(global['gds'].cfg.web.port, () => {
		global['modules'].logs.log("Server is listening on port: "+global['gds'].cfg.web.port);
	});

	// DEBUG OUTPUT: list all routes with HTTP method
	setTimeout(function () {
		function print (path, layer) {
			if (layer.route) {
				layer.route.stack.forEach(print.bind(null, path.concat(split(layer.route.path))))
			} else if (layer.name === 'router' && layer.handle.stack) {
				layer.handle.stack.forEach(print.bind(null, path.concat(split(layer.regexp))))
			} else if (layer.method) {
				console.log('%s /%s',
					layer.method.toUpperCase(),
					path.concat(split(layer.regexp)).filter(Boolean).join('/')
				);
			}
		}

		function split (thing) {
			if (typeof thing === 'string') {
				return thing.split('/')
			} else if (thing.fast_slash) {
				return ''
			} else {
				var match = thing.toString()
					.replace('\\/?', '')
					.replace('(?=\\/|$)', '$')
					.match(/^\/\^((?:\\[.*+?^${}()|[\]\\\/]|[^.*+?^${}()|[\]\\\/])*)\$\//)

				return match
					? match[1].replace(/\\(.)/g, '$1').split('/')
					: '<complex:' + thing.toString() + '>'
			}
		}

		app._router.stack.forEach(print.bind(null, []))
	}, 1500);
};

module.exports = methods;