import { ActionFunctionArgs, data, redirect } from 'react-router';
import { LoadContext } from '~/server';
import ResponseError from '~/server/headscale/api-error';
import { Key } from '~/types';
import log from '~/utils/log';

export async function loginAction({
	request,
	context,
}: ActionFunctionArgs<LoadContext>) {
	const formData = await request.formData();
	const apiKey = formData.has('api_key')
		? String(formData.get('api_key'))
		: undefined;

	if (apiKey === undefined) {
		log.warn('auth', 'Request made without API key');
		log.warn(
			'auth',
			'If this is unexpected, ensure your reverse proxy (if applicable) is configured correctly',
		);
		throw data('Missing `api_key`', { status: 400 });
	}

	if (apiKey.length === 0) {
		log.warn('auth', 'Request made with empty API key');
		log.warn(
			'auth',
			'If this is unexpected, ensure your reverse proxy (if applicable) is configured correctly',
		);
		throw data('Received an empty `api_key`', { status: 400 });
	}

	try {
		const { apiKeys } = await context.client.get<{ apiKeys: Key[] }>(
			'v1/apikey',
			apiKey,
		);

		// We don't need to check for 0 API keys because this request cannot
		// be authenticated correctly without an API key
		const lookup = apiKeys.find((key) => apiKey.startsWith(key.prefix));
		if (!lookup) {
			return {
				success: false,
				message: 'API key was not found in the Headscale database',
			};
		}

		if (lookup.expiration === null || lookup.expiration === undefined) {
			log.error('auth', 'Got an API key without an expiration');
			throw data('API key is malformed', { status: 500 });
		}

		const expiry = new Date(lookup.expiration);
		if (expiry.getTime() < Date.now()) {
			return {
				success: false,
				message: 'API key has expired',
			};
		}

		// Set the session
		const session = await context.sessions.getOrCreate(request);
		const expiresDays = Math.round(
			(expiry.getTime() - Date.now()) / 1000 / 60 / 60 / 24,
		);

		session.set('state', 'auth');
		session.set('api_key', apiKey);
		session.set('user', {
			subject: 'unknown-non-oauth',
			name: `${lookup.prefix}...`,
			email: `expires@${expiresDays.toString()}-days`,
		});

		return redirect('/machines', {
			headers: {
				'Set-Cookie': await context.sessions.commit(session, {
					maxAge: expiry.getTime() - Date.now(),
				}),
			},
		});
	} catch (error) {
		if (error instanceof ResponseError) {
			// TODO: What in gods name is wrong with the headscale API?
			if (
				error.status === 401 ||
				error.status === 403 ||
				(error.status === 500 && error.response.trim() === 'Unauthorized')
			) {
				return {
					success: false,
					message: 'API key is invalid (it may be incorrect or expired)',
				};
			}
		}

		log.error('auth', 'Error while validating API key: %s', error);
		log.debug('auth', 'Error details: %o', error);
		return {
			success: false,
			message: 'Error while validating API key (see logs for details)',
		};
	}
}