import _ from "lodash"
import auth, {BasicAuthCheckerCallback} from "http-auth"
import bodyParser from "body-parser"
import compress from "compression"
import express, {Express, NextFunction, Request, Response} from "express"
import {promises as fs} from "graceful-fs"

import {config} from "./config";

const app: Express = express();

const router = express.Router();

// urls beneath /internal are protected
const internalAuth = auth.basic(
    {
        realm: 'Knotenformular - Intern'
    },
    function (username: string, password: string, callback: BasicAuthCheckerCallback): void {
        callback(
            config.server.internal.active &&
            username === config.server.internal.user &&
            password === config.server.internal.password
        );
    }
);
router.use('/internal', auth.connect(internalAuth));

router.use(bodyParser.json());
router.use(bodyParser.urlencoded({ extended: true }));

const adminDir = __dirname + '/../admin';
const clientDir = __dirname + '/../client';
const templateDir = __dirname + '/templates';

const jsTemplateFiles = [
    '/config.js'
];

function usePromise(f: (req: Request, res: Response) => Promise<void>): void {
    router.use((req: Request, res: Response, next: NextFunction): void => {
        f(req, res).then(next).catch(next)
    });
}

router.use(compress());

async function serveTemplate (mimeType: string, req: Request, res: Response): Promise<void> {
    const body = await fs.readFile(templateDir + '/' + req.path + '.template', 'utf8');

    res.writeHead(200, { 'Content-Type': mimeType });
    res.end(_.template(body)({ config: config.client }));
}

usePromise(async (req: Request, res: Response): Promise<void> => {
    if (jsTemplateFiles.indexOf(req.path) >= 0) {
        await serveTemplate('application/javascript', req, res);
    }
});

router.use('/internal/admin', express.static(adminDir + '/'));
router.use('/', express.static(clientDir + '/'));

app.use(config.server.rootPath, router);

export default app;