const fastify = require('fastify')({ logger: true })
const level = require('level')
const { nanoid } = require('nanoid')

const db = level('./db', { valueEncoding: 'json' })

//Basic home route
fastify.get('/', async (request, reply) => {
    return { hello: 'world' }
})

//Automagic Amazn redirects on /a/
fastify.get('/a/:id', async (req, res) => {
    res.redirect(302, `https://amazon.de/dp/${req.params.id}`)
})

//Automagic Youtube redirects on /yt/
fastify.get('/yt/:id', async (req, res) => {
    res.redirect(302, `https://youtu.be/${req.params.id}`)
})

//Normal shorturls
fastify.get('/:id', async (req, res) => {
    try {
        const target = await db.get(req.params.id);
        res.redirect(302, target);
    } catch (error) {
        res.statusCode = 404;
        return 404;
    }
})

//Create new urls
fastify.post('/new', async (req, res) => {
    const target = req.body?.target;
    let shortcode = req.body?.code;
    if (!req.body?.target) {
        res.statusCode = 400;
        return "Missing target";
    }
    if (!shortcode) {
        shortcode = nanoid(12);
    }
    else{
        try {
            const exists = await db.get(shortcode);
            if(exists){
                res.statusCode = 400;
                return "Shortcode already exists, please choose another code";
            }
        } catch (error) {
            if(!error.notFound){
                res.statusCode=500;
                return "Internal Server Error."
            }
        }
    }
    try {
        await db.put(shortcode, target);
    } catch (error) {
        res.statusCode = 500;
        return "DB ERROR";
    }
    return {
        shortcode,
        url: `http://localhost:3000/${shortcode}`,
        target
    };
})

// Run the server!
const start = async () => {
    try {
        await fastify.listen(3000)
    } catch (err) {
        fastify.log.error(err)
        process.exit(1)
    }
}
start()