const dayjs = require('dayjs');

const adjectives = require('../res/adjectives.json');
const crabs = require('../res/crabs.json');

const capitalize = (string) => string.charAt(0).toUpperCase() + string.slice(1);

const generateId = (name) => {
	const id = name.trim().toLowerCase().replace(/[^A-Za-z0-9 ]/g, '').replace(/\s+/g, '-');
	const number = Math.floor(100000 + Math.random() * 900000);
	return `${id}-${number}`;
};

const generateName = () => {
	return `${capitalize(adjectives[Math.floor(Math.random() * adjectives.length)])} ${crabs[Math.floor(Math.random() * crabs.length)]} Crab`;
};

module.exports = async (req, res) => {
	const { event } = req.body;

	try {
		const name = event.name.trim() === '' ? generateName() : event.name.trim();
		let eventId = generateId(name);
		const currentTime = dayjs().unix();

    let eventResult;
    do {
      const query = req.datastore.createQuery(req.types.event)
        .select('__key__')
        .filter('__key__', req.datastore.key([req.types.event, eventId]));

      eventResult = (await req.datastore.runQuery(query))[0][0];

      if (eventResult !== undefined) {
        eventId = generateId(name);
      }
    } while (eventResult !== undefined);

    const entity = {
			key: req.datastore.key([req.types.event, eventId]),
			data: {
				name: name,
				created: currentTime,
				times: event.times,
				timezone: event.timezone,
			},
		};

		await req.datastore.insert(entity);

		res.status(201).send({
			id: eventId,
			name: name,
			created: currentTime,
			times: event.times,
      timezone: event.timezone,
		});
	} catch (e) {
		console.error(e);
		res.sendStatus(400);
	}
};