import React from 'react';
import { Col, ListGroup, Card, CardDeck } from 'react-bootstrap'; // eslint-disable-line no-unused-vars
import axios from 'axios'; // eslint-disable-line no-unused-vars
import { Link } from 'react-router-dom'; // eslint-disable-line no-unused-vars
/*eslint no-console: ["error", { allow: ["warn", "error", "info"] }] */

class VideoList extends React.Component {
	constructor(props) {
		super(props);
		this.state = {
			error: null,
			isLoaded: false,
			items: [],
			headers: null
		};
	}

	componentDidMount() {
		axios.get('http://site1825.tw.cs.unibo.it/video.json').then(
			response => {
				this.shuffleArray(response.data);
				this.setState({
					headers: response.config
				});
				return this.getThumbnails(response.data);
			},
			// Note: it's important to handle errors here
			// instead of a catch() block so that we don't swallow
			// exceptions from actual bugs in components.
			error => {
				console.error(error);
				this.setState({
					isLoaded: true,
					error
				});
			}
		);
	}

	render() {
		const { error, isLoaded, items, headers } = this.state;
		if (error) {
			return (
				<React.Fragment>
					Error: {error.message} -- Cannot get {error.config.url}
				</React.Fragment>
			);
		} else if (!isLoaded) {
			return <React.Fragment>Loading...</React.Fragment>;
		} else {
			return (
				<React.Fragment>
					<Col className="my-2" xs="12" sm="12">
						<code>
							Url loaded: <span className="bg-dark">{headers.url}</span>
						</code>
						<br />
						<code>Total videos: {items.length}</code>
					</Col>
					{items.map(item => (
						<Col key={item.videoID} lg="4" md="6">
							<Card className="my-1">
								<Link to={{ pathname: '/video/' + item.videoID }}>
									<ListGroup>
										<ListGroup.Item className="bg-secondary text-white">
											{item.artist} - {item.title}
										</ListGroup.Item>
										<ListGroup.Item>
											<span className="bg-info text-white">
												{' '}
												{item.videoID}
											</span>{' '}
											{item.category}
										</ListGroup.Item>
									</ListGroup>
								</Link>
							</Card>
						</Col>
					))}
				</React.Fragment>
			);
		}
	}
	shuffleArray(videoarray) {
		for (let i = videoarray.length - 1; i > 0; i--) {
			const j = Math.floor(Math.random() * (i + 1));
			[videoarray[i], videoarray[j]] = [videoarray[j], videoarray[i]]; // eslint-disable-line no-param-reassign
		}
		// Durstenfeld shuffle.
		// https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle#The_modern_algorithm
	}
	getThumbnails(videoItems) {
		let idToLookFor = videoItems.map(item => item.videoID);
		let finalChunk = (videoItems.length % 50) + 100;
		axios
			.all([
				// chain 3 parallel get
				axios.get('https://www.googleapis.com/youtube/v3/videos', {
					params: {
						part: 'snippet',
						id: idToLookFor.slice(0, 50).toString(),
						key: 'AIzaSyA21Odw9UdfiOJnxvA_eDfOW0OxuUfHKig',
						fields: 'items(id,snippet/thumbnails/medium)'
					}
				}),
				axios.get('https://www.googleapis.com/youtube/v3/videos', {
					//chain multiple get into promises
					params: {
						part: 'snippet',
						id: idToLookFor.slice(50, 100).toString(),
						key: 'AIzaSyA21Odw9UdfiOJnxvA_eDfOW0OxuUfHKig',
						fields: 'items(id,snippet/thumbnails/medium)'
					}
				}),
				axios.get('https://www.googleapis.com/youtube/v3/videos', {
					//chain multiple get into promises
					params: {
						part: 'snippet',
						id: idToLookFor.slice(100, finalChunk).toString(),
						key: 'AIzaSyA21Odw9UdfiOJnxvA_eDfOW0OxuUfHKig',
						fields: 'items(id,snippet/thumbnails/medium)'
					}
				})
			])
			.then(
				axios.spread((res1, res2, res3) => {
					let allres = [].concat(
						res1.data.items,
						res2.data.items,
						res3.data.items
					);
					allres.forEach(resCurrentValue => {
						Object.defineProperty(
							videoItems.find(videoItem => {
								return videoItem.videoID === resCurrentValue.id;
							}),
							'thumbnail',
							{ value: resCurrentValue.snippet.thumbnails.medium.url }
						);
					});
				})
			);
		return this.setState({
			isLoaded: true,
			items: videoItems
		});
	}
}

export default VideoList;