import React from 'react';
import PropTypes from 'prop-types';
import { Platform, View, TextInput, FlatList, BackHandler, ActivityIndicator, SafeAreaView } from 'react-native';
import { connect } from 'react-redux';

import { iconsMap } from '../../Icons';
import database from '../../lib/realm';
import RocketChat from '../../lib/rocketchat';
import RoomItem from '../../presentation/RoomItem';
import styles from './styles';
import debounce from '../../utils/debounce';
import LoggedView from '../View';
import log from '../../utils/log';
import I18n from '../../i18n';

const ROW_HEIGHT = 70.5;

@connect(state => ({
	userId: state.login.user && state.login.user.id,
	server: state.server.server,
	Site_Url: state.settings.Site_Url,
	searchText: state.rooms.searchText,
	loadingServer: state.server.loading
}))
/** @extends React.Component */
export default class RoomsListView extends LoggedView {
	static propTypes = {
		navigator: PropTypes.object,
		userId: PropTypes.string,
		Site_Url: PropTypes.string,
		server: PropTypes.string,
		searchText: PropTypes.string,
		loadingServer: PropTypes.bool
	}

	constructor(props) {
		super('RoomsListView', props);

		this.state = {
			search: [],
			rooms: [],
			loading: true
		};
		props.navigator.setOnNavigatorEvent(this.onNavigatorEvent.bind(this));
	}

	async componentWillMount() {
		this.initDefaultHeader();
	}

	componentDidMount() {
		this.getSubscriptions();
	}

	componentWillReceiveProps(props) {
		if (props.server && props.loadingServer) {
			this.setState({ loading: true });
		} else if (props.server && !props.loadingServer) {
			this.getSubscriptions();
		} else if (this.props.searchText !== props.searchText) {
			this.search(props.searchText);
		}
	}

	componentWillUnmount() {
		this.updateState.stop();
		if (this.data) {
			this.data.removeAllListeners();
		}
		if (this.timeout) {
			clearTimeout(this.timeout);
		}
	}

	onNavigatorEvent(event) {
		const { navigator } = this.props;
		if (event.type === 'NavBarButtonPress') {
			if (event.id === 'createChannel') {
				navigator.push({
					screen: 'SelectedUsersView',
					title: I18n.t('Select_Users'),
					passProps: {
						nextAction: 'CREATE_CHANNEL'
					}
				});
			} else if (event.id === 'sideMenu' && Platform.OS === 'ios') {
				navigator.toggleDrawer({
					side: 'left',
					animated: true,
					to: 'missing'
				});
			} else if (event.id === 'search') {
				this.initSearchingAndroid();
			} else if (event.id === 'cancelSearch') {
				this.cancelSearchingAndroid();
			}
		} else if (event.type === 'ScreenChangedEvent' && event.id === 'didAppear') {
			this.props.navigator.setDrawerEnabled({
				side: 'left',
				enabled: true
			});
		}
	}

	onSearchChangeText(text) {
		this.search(text);
	}

	getSubscriptions = () => {
		if (this.data && this.data.removeListener) {
			this.data.removeListener(this.updateState);
		}
		if (this.props.server && this.hasActiveDB()) {
			this.data = database.objects('subscriptions').filtered('archived != true && open == true').sorted('roomUpdatedAt', true);
			this.data.addListener(this.updateState);
		}
		this.timeout = setTimeout(() => {
			this.setState({ loading: false });
		}, 200);
	}

	initDefaultHeader = () => {
		const { navigator } = this.props;
		const rightButtons = [{
			id: 'createChannel',
			icon: iconsMap.add,
			testID: 'rooms-list-view-create-channel'
		}];

		if (Platform.OS === 'android') {
			rightButtons.push({
				id: 'search',
				icon: iconsMap.search
			});
		}

		navigator.setButtons({
			leftButtons: [{
				id: 'sideMenu',
				icon: Platform.OS === 'ios' ? iconsMap.menu : undefined,
				testID: 'rooms-list-view-sidebar'
			}],
			rightButtons
		});
	}

	initSearchingAndroid = () => {
		const { navigator } = this.props;
		navigator.setButtons({
			leftButtons: [{
				id: 'cancelSearch',
				icon: iconsMap['md-arrow-back']
			}],
			rightButtons: []
		});
		navigator.setStyle({
			navBarCustomView: 'RoomsListSearchView',
			navBarComponentAlignment: 'fill'
		});
		BackHandler.addEventListener('hardwareBackPress', this.handleBackPress);
	}

	// this is necessary during development (enables Cmd + r)
	hasActiveDB = () => database && database.databases && database.databases.activeDB;

	cancelSearchingAndroid = () => {
		if (Platform.OS === 'android') {
			this.props.navigator.setStyle({
				navBarCustomView: ''
			});
			this.setState({ search: [] });
			this.initDefaultHeader();
			BackHandler.removeEventListener('hardwareBackPress', this.handleBackPress);
		}
	}

	handleBackPress = () => {
		this.cancelSearchingAndroid();
		return true;
	}

	updateState = debounce(() => {
		this.setState({ rooms: this.data.slice() });
	})

	async search(text) {
		const searchText = text.trim();
		if (searchText === '') {
			delete this.oldPromise;
			return this.setState({
				search: []
			});
		}

		let data = database.objects('subscriptions').filtered('name CONTAINS[c] $0', searchText).slice(0, 7);

		const usernames = data.map(sub => sub.name);
		try {
			if (data.length < 7) {
				if (this.oldPromise) {
					this.oldPromise('cancel');
				}

				const { users, rooms } = await Promise.race([
					RocketChat.spotlight(searchText, usernames, { users: true, rooms: true }),
					new Promise((resolve, reject) => this.oldPromise = reject)
				]);

				data = data.concat(users.map(user => ({
					...user,
					rid: user.username,
					name: user.username,
					t: 'd',
					search: true
				})), rooms.map(room => ({
					rid: room._id,
					...room,
					search: true
				})));

				delete this.oldPromise;
			}
			this.setState({
				search: data
			});
		} catch (e) {
			// alert(JSON.stringify(e));
		}
	}

	goRoom = (rid, name) => {
		this.props.navigator.push({
			screen: 'RoomView',
			title: name,
			passProps: {
				room: { rid, name },
				rid,
				name
			}
		});
		this.cancelSearchingAndroid();
	}

	_onPressItem = async(item = {}) => {
		if (!item.search) {
			const { rid, name } = item;
			return this.goRoom(rid, name);
		}
		if (item.t === 'd') {
			// if user is using the search we need first to join/create room
			try {
				const { username } = item;
				const sub = await RocketChat.createDirectMessage(username);
				const { rid } = sub;
				return this.goRoom(rid, username);
			} catch (e) {
				log('RoomsListView._onPressItem', e);
			}
		} else {
			const { rid, name } = item;
			return this.goRoom(rid, name);
		}
	}

	renderSearchBar = () => (
		<View style={styles.searchBoxView}>
			<TextInput
				underlineColorAndroid='transparent'
				style={styles.searchBox}
				onChangeText={text => this.onSearchChangeText(text)}
				returnKeyType='search'
				placeholder={I18n.t('Search')}
				clearButtonMode='while-editing'
				blurOnSubmit
				autoCorrect={false}
				autoCapitalize='none'
				testID='rooms-list-view-search'
			/>
		</View>
	);

	renderItem = ({ item }) => {
		const id = item.rid.replace(this.props.userId, '').trim();
		return (<RoomItem
			alert={item.alert}
			unread={item.unread}
			userMentions={item.userMentions}
			favorite={item.f}
			lastMessage={item.lastMessage}
			name={item.name}
			_updatedAt={item.roomUpdatedAt}
			key={item._id}
			id={id}
			type={item.t}
			baseUrl={this.props.Site_Url}
			onPress={() => this._onPressItem(item)}
			testID={`rooms-list-view-item-${ item.name }`}
		/>);
	}

	renderList = () => {
		if (this.state.loading) {
			return <ActivityIndicator style={styles.loading} />;
		}
		return (
			<FlatList
				data={this.state.search.length > 0 ? this.state.search : this.state.rooms}
				extraData={this.state.search.length > 0 ? this.state.search : this.state.rooms}
				keyExtractor={item => item.rid}
				style={styles.list}
				renderItem={this.renderItem}
				ListHeaderComponent={Platform.OS === 'ios' ? this.renderSearchBar : null}
				contentOffset={Platform.OS === 'ios' ? { x: 0, y: 38 } : {}}
				getItemLayout={(data, index) => ({ length: ROW_HEIGHT, offset: ROW_HEIGHT * index, index })}
				enableEmptySections
				removeClippedSubviews
				keyboardShouldPersistTaps='always'
				testID='rooms-list-view-list'
			/>
		);
	}

	render = () => (
		<SafeAreaView style={styles.container} testID='rooms-list-view'>
			{this.renderList()}
		</SafeAreaView>
	)
}