'use strict';

const util = require('util');
const crypto = require('crypto');

const knex = require('./knex');
const { curateUser } = require('./users');
const { HttpError } = require('./errors');

const scrypt = util.promisify(crypto.scrypt);

async function verifyPassword(password, storedPassword) {
	const [salt, hash] = storedPassword.split('/');
	const hashedPassword = (await scrypt(password, salt, 64)).toString('hex');

	if (hashedPassword === hash) {
		return true;
	}

	throw new HttpError('Username or password incorrect', 401);
}

async function login(credentials) {
	const user = await knex('users')
		.select('users.*', 'users_roles.abilities as role_abilities')
		.where('username', credentials.username)
		.orWhere('email', credentials.username)
		.leftJoin('users_roles', 'users_roles.role', 'users.role')
		.first();

	if (!user) {
		throw new HttpError('Username or password incorrect', 401);
	}

	await verifyPassword(credentials.password, user.password);

	return curateUser(user);
}

async function signup(credentials) {
	if (!credentials.username) {
		throw new HttpError('Username required', 400);
	}

	if (!credentials.email) {
		throw new HttpError('E-mail required', 400);
	}

	if (credentials.password?.length < 3) {
		throw new HttpError('Password must be 3 characters or longer', 400);
	}

	const existingUser = await knex('users')
		.where('username', credentials.username)
		.orWhere('email', credentials.email)
		.first();

	if (existingUser) {
		throw new HttpError('Username or e-mail already in use', 409);
	}

	const salt = crypto.randomBytes(16).toString('hex');
	const hashedPassword = (await scrypt(credentials.password, salt, 64)).toString('hex');
	const storedPassword = `${salt}/${hashedPassword}`;

	const [user] = await knex('users')
		.insert({
			username: credentials.username,
			email: credentials.email,
			password: storedPassword,
		})
		.returning('*');

	await knex('stashes').insert({
		user_id: user.id,
		name: 'Favorites',
		slug: 'favorites',
		public: false,
	});

	return curateUser(user);
}

module.exports = {
	login,
	signup,
};