const fastify = require('fastify')({ trustProxy: process.env.HTTP_TRUST_PROXY === 'true' });
const oauth = require('@fastify/oauth2');
const { randomBytes } = require('crypto');
const { short } = require('leeks.js');
const { join } = require('path');
const { files } = require('node-dir');
const { PermissionsBitField } = require('discord.js');

process.env.ORIGIN = process.env.HTTP_INTERNAL || process.env.HTTP_EXTERNAL;

module.exports = async client => {
	// cookies plugin, must be registered before oauth2 since oauth2@7.2.0
	fastify.register(require('@fastify/cookie'));

	// jwt plugin
	fastify.register(require('@fastify/jwt'), {
		cookie: {
			cookieName: 'token',
			signed: false,
		},
		secret: process.env.ENCRYPTION_KEY,
	});

	// oauth2 plugin
	fastify.states = new Map();
	fastify.register(oauth, {
		callbackUri: `${process.env.HTTP_EXTERNAL}/auth/callback`,
		callbackUriParams: { prompt: 'none' },
		checkStateFunction: async req => {
			if (req.query.state !== req.cookies['oauth2-redirect-state']) {
				throw new Error('Invalid state');
			}
			return true;
		},
		credentials: {
			auth: oauth.DISCORD_CONFIGURATION,
			client: {
				id: client.user.id,
				secret: process.env.DISCORD_SECRET,
			},
		},
		generateStateFunction: req => {
			const state = randomBytes(12).toString('hex');
			fastify.states.set(state, req.query.r);
			return state;
		},
		name: 'discord',
		scope: ['applications.commands.permissions.update', 'guilds', 'identify'],
		startRedirectPath: '/auth/login',
	});


	// auth
	fastify.decorate('authenticate', async (req, res) => {
		try {
			const data = await req.jwtVerify();
			if (data.expiresAt < Date.now()) throw 'expired';
			if (data.createdAt < new Date(process.env.INVALIDATE_TOKENS).getTime()) throw 'expired';
		} catch (error) {
			return res.code(401).send({
				error: 'Unauthorised',
				message: error === 'expired' ? 'Your token has expired; please re-authenticate.' : 'You are not authenticated.',
				statusCode: 401,
			});
		}
	});

	fastify.decorate('isAdmin', async (req, res) => {
		try {
			const userId = req.user.id;
			const guildId = req.params.guild;
			const guild = client.guilds.cache.get(guildId);
			if (!guild) {
				return res.code(404).send({
					error: 'Not Found',
					message: 'The requested resource could not be found.',
					statusCode: 404,

				});
			}
			const guildMember = await guild.members.fetch(userId);
			const isAdmin = guildMember?.permissions.has(PermissionsBitField.Flags.ManageGuild) || client.supers.includes(userId);
			if (!isAdmin) {
				return res.code(403).send({
					error: 'Forbidden',
					message: 'You are not permitted for this action.',
					statusCode: 403,

				});
			}
		} catch (err) {
			res.send(err);
		}
	});

	// body processing
	fastify.addHook('preHandler', (req, res, done) => {
		if (req.body && typeof req.body === 'object') {
			for (const prop in req.body) {
				if (typeof req.body[prop] === 'string') {
					req.body[prop] = req.body[prop].trim();
				}
			}
		}
		done();
	});

	// logging
	fastify.addHook('onResponse', (req, res, done) => {
		done();
		const status = (res.statusCode >= 500
			? '&4'
			: res.statusCode >= 400
				? '&6'
				: res.statusCode >= 300
					? '&3'
					: res.statusCode >= 200
						? '&2'
						: '&f') + res.statusCode;
		let responseTime = res.elapsedTime.toFixed(2);
		responseTime = (responseTime >= 100
			? '&c'
			: responseTime >= 10
				? '&e'
				: '&a') + responseTime + 'ms';
		const level = req.routeOptions.url === '/status'
			? 'debug'
			:  req.routeOptions.url === '/*'
				? 'verbose'
				: 'info';
		client.log[level].http(short(`${req.id} ${req.ip} ${req.method} ${req.routeOptions.url ?? '*'} &m-+>&r ${status}&b in ${responseTime}`));
		if (!req.routeOptions.url) client.log.verbose.http(`${req.id} ${req.method} ${req.url}`);
		done();
	});

	fastify.addHook('onError', async (req, res, err) => client.log.error.http(req.id, err));

	// route loading
	const dir = join(__dirname, '/routes');
	files(dir, {
		exclude: /^\./,
		match: /.js$/,
		sync: true,
	}).forEach(file => {
		const path = file
			.substring(0, file.length - 3) // remove `.js`
			.substring(dir.length) // remove higher directories
			.replace(/\\/g, '/') // replace `\` with `/` because Windows is stupid
			.replace(/\[(\w+)\]/gi, ':$1') // convert [] to :
			.replace('/index', '') || '/'; // remove index
		const route = require(file);

		Object.keys(route).forEach(method => fastify.route({
			config: { client },
			method: method.toUpperCase(),
			path,
			...route[method](fastify),
		})); // register route
	});

	const { handler } = await import('@discord-tickets/settings/build/handler.js');

	// https://stackoverflow.com/questions/72317071/how-to-set-up-fastify-correctly-so-that-sveltekit-works-fine
	fastify.all('/*', {}, (req, res) => handler(req.raw, res.raw, () => { }));

	// start the fastify server
	fastify.listen({
		host: process.env.HTTP_HOST,
		port: process.env.HTTP_PORT,
	}, (err, addr) => {
		if (err) client.log.error.http(err);
		else client.log.success.http(`Listening at ${addr}`);
	});

	process.on('sveltekit:error', ({
		error,
		errorId,
	}) => {
		client.log.error.http(`SvelteKit ${errorId} ${error}`);
	});
};