import React, { useState, useEffect } from 'react';
import { Link } from 'react-router-dom';
import { Helmet } from 'react-helmet';
import localForage from 'localforage';
import { sourceLink, infoLine, logos } from './utils.js';

function Feed({ updateCache }) {
	const [stories, setStories] = useState(() => JSON.parse(localStorage.getItem('stories')) || false);
	const [error, setError] = useState(false);

	useEffect(() => {
		fetch('/api')
			.then(res => res.json())
			.then(
				(result) => {
					const updated = !stories || stories[0].id !== result.stories[0].id;
					console.log('updated:', updated);

					setStories(result.stories);
					localStorage.setItem('stories', JSON.stringify(result.stories));

					if (updated) {
						localForage.clear();
						result.stories.forEach((x, i) => {
							fetch('/api/' + x.id)
								.then(res => res.json())
								.then(result => {
									localForage.setItem(x.id, result.story)
										.then(console.log('preloaded', x.id, x.title));
									updateCache(x.id, result.story);
								}, error => {}
							);
						});
					}
				},
				(error) => {
					setError(true);
				}
			);
	}, [updateCache]);

	return (
		<div className='container'>
			<Helmet>
				<title>QotNews</title>
				<meta name="robots" content="index" />
			</Helmet>
			{error && <p>Connection error?</p>}
			{stories ?
				<div>
					{stories.map(x =>
						<div className='item' key={x.id}>
							<div className='title'>
								<Link className='link' to={'/' + x.id}>
									<img className='source-logo' src={logos[x.source]} alt='source logo' /> {x.title}
								</Link>

								<span className='source'>
									({sourceLink(x)})
								</span>
							</div>

							{infoLine(x)}
						</div>
					)}
				</div>
			:
				<p>loading...</p>
			}
		</div>
	);
}

export default Feed;