'use strict';

const bcrypt = require('bcrypt')
	, dynamicResponse = require(__dirname+'/../../lib/misc/dynamic.js')
	, { Accounts } = require(__dirname+'/../../db/')
	, OTPAuth = require('otpauth');

module.exports = async (req, res) => {

	const username = req.body.username.toLowerCase();
	const password = req.body.password;
	let goto = req.body.goto;
	// we don't want to redirect the user to random sites
	if (goto == null || !/^\/[0-9a-zA-Z][0-9a-zA-Z._/-]*$/.test(goto)) {
		goto = '/account.html';
	}
	const failRedirect = `/login.html${goto ? '?goto='+encodeURIComponent(goto) : ''}`;

	//fetch an account
	const account = await Accounts.findOne(username);

	//if the account doesnt exist, reject
	if (!account) {
		return dynamicResponse(req, res, 403, 'message', {
			'title': 'Forbidden',
			'message': 'Incorrect login credentials',
			'redirect': failRedirect
		});
	}

	// bcrypt compare input to saved hash
	const passwordMatch = await bcrypt.compare(password, account.passwordHash);

	//if hashes matched
	if (passwordMatch === false) {
		return dynamicResponse(req, res, 403, 'message', {
			'title': 'Forbidden',
			'message': 'Incorrect login credentials',
			'redirect': failRedirect
		});
	}

	if (account.twofactor) {
		const totp = new OTPAuth.TOTP({
			secret: account.twofactor,
			algorithm: 'SHA256',
		});
		const delta = await totp.validate({
			token: req.body.twofactor,
			algorithm: 'SHA256',
			window: 1,
		});
		if (delta === null) {
			return dynamicResponse(req, res, 403, 'message', {
				'title': 'Forbidden',
				'message': 'Incorrect login credentials', //better to not tell them, i think
				'redirect': failRedirect
			});
		}
	}

	// add the account to the session and authenticate if password was correct
	req.session.user = account._id;

	//successful login
	await Accounts.updateLastActiveDate(username);
	return res.redirect(goto);

};