const fetch = require('node-fetch');
const allSettled = require('promise.allsettled');
const lastfm = 'http://ws.audioscrobbler.com/2.0/'
const quality = 3;

allSettled.shim();

async function asklastfm(apikey, query) {
	try {
		let url = `${lastfm}?format=json&api_key=${apikey}&${query}`;
		let res = await fetch(url);
		return res.json();
	} catch(e) {
		console.log(query);
		throw e;
	}
}

async function getalbum(apikey, elem) {
	let query, info = undefined;

	if (elem['album'] !== undefined) {
		query =`method=album.getinfo&artist=${encodeURIComponent(elem['artist'])}&album=${encodeURIComponent(elem['album'])}`;
		info  = await asklastfm(apikey, query);
	} else if (elem['track'] !== undefined) {
		query =`method=track.getinfo&artist=${encodeURIComponent(elem['artist'])}&track=${encodeURIComponent(elem['track'])}`;
		info  = (await asklastfm(apikey, query))['track']
	}

	if (info !== undefined) {
		return info['album'];
	} else {
		return undefined;
	}
}

exports.updatecovers = async function (apikey, list) {
	let promises = list.map(async elem => {
		if (!elem.cover) {
			let info = await getalbum(apikey, elem);
			if (typeof info === 'object' && info['image'] instanceof Array) {
				let count = info['image'].length;
				let index = count > quality ? quality : count;
				let image = info['image'][index]['#text'];
				if (image) {
					elem['cover'] = image;
				}
			}
		}
		return elem;
	});
	return Promise.allSettled(promises);
}