/**
 * External dependencies
 */
import { __ } from '@wordpress/i18n';
import { useEffect, useMemo, useState } from '@wordpress/element';
import { compose } from '@wordpress/compose';
import {
	__experimentalNavigation as Navigation,
	__experimentalNavigationBackButton as NavigationBackButton,
	__experimentalNavigationMenu as NavigationMenu,
	__experimentalNavigationGroup as NavigationGroup,
} from '@wordpress/components';
import { getAdminLink } from '@woocommerce/wc-admin-settings';
import { NAVIGATION_STORE_NAME } from '@woocommerce/data';
import { withSelect } from '@wordpress/data';

/**
 * Internal dependencies
 */
import { addHistoryListener, getMatchingItem } from '../../utils';
import Header from '../header';
import Item from '../../components/Item';

const Container = ( { menuItems } ) => {
	useEffect( () => {
		// Collapse the original WP Menu.
		const adminMenu = document.getElementById( 'adminmenumain' );
		adminMenu.classList.add( 'folded' );
	}, [] );

	const dashboardUrl = getAdminLink( '' );

	const categories = menuItems.filter( ( item ) => item.isCategory );
	categories.push( {
		capability: 'manage_woocommerce',
		id: 'woocommerce',
		isCategory: true,
		menuId: 'primary',
		migrate: true,
		order: 10,
		parent: '',
		title: 'WooCommerce',
	} );

	const [ activeItem, setActiveItem ] = useState( 'woocommerce-home' );
	const [ activeLevel, setActiveLevel ] = useState( 'woocommerce' );

	useEffect( () => {
		const initialMatchedItem = getMatchingItem( menuItems );
		setActiveItem( initialMatchedItem );
		setActiveLevel( initialMatchedItem.parent );

		const removeListener = addHistoryListener( () => {
			setTimeout( () => {
				const matchedItem = getMatchingItem( menuItems );
				if ( matchedItem ) {
					setActiveItem( matchedItem );
				}
			}, 0 );
		} );

		return removeListener;
	}, [ menuItems ] );

	const getMenuItemsByCategory = ( items ) => {
		return items.reduce( ( acc, item ) => {
			if ( ! acc[ item.parent ] ) {
				acc[ item.parent ] = [ [], [], [] ];
			}
			let index = 0;
			if ( item.menuId === 'secondary' ) {
				index = 1;
			} else if ( item.menuId === 'plugins' ) {
				index = 2;
			}
			acc[ item.parent ][ index ].push( item );
			return acc;
		}, {} );
	};

	const categorizedItems = useMemo(
		() => getMenuItemsByCategory( menuItems ),
		[ menuItems ]
	);

	return (
		<div className="woocommerce-navigation">
			<Header />
			<Navigation
				activeItem={ activeItem ? activeItem.id : null }
				activeMenu={ activeLevel }
				onActivateMenu={ ( ...args ) => {
					const navDomRef = document.querySelector(
						'.components-navigation'
					);

					if ( navDomRef ) {
						navDomRef.scrollTop = 0;
					}

					setActiveLevel( ...args );
				} }
			>
				{ activeLevel === 'woocommerce' && dashboardUrl && (
					<NavigationBackButton
						className="woocommerce-navigation__back-to-dashboard"
						href={ dashboardUrl }
						backButtonLabel={ __(
							'WordPress Dashboard',
							'woocommerce-navigation'
						) }
					></NavigationBackButton>
				) }
				{ categories.map( ( category ) => {
					const [
						primaryItems,
						secondaryItems,
						pluginItems,
					] = categorizedItems[ category.id ] || [ [], [], [] ];
					return (
						<NavigationMenu
							key={ category.id }
							title={ category.title }
							menu={ category.id }
							parentMenu={ category.parent }
							backButtonLabel={ category.backButtonLabel || null }
						>
							{ !! primaryItems.length && (
								<NavigationGroup>
									{ primaryItems.map( ( item ) => (
										<Item key={ item.id } item={ item } />
									) ) }
								</NavigationGroup>
							) }
							{ !! pluginItems.length && (
								<NavigationGroup
									title={
										category.id === 'woocommerce'
											? __(
													'Extensions',
													'woocommerce-admin'
											  )
											: null
									}
								>
									{ pluginItems.map( ( item ) => (
										<Item key={ item.id } item={ item } />
									) ) }
								</NavigationGroup>
							) }
							{ !! secondaryItems.length && (
								<NavigationGroup>
									{ secondaryItems.map( ( item ) => (
										<Item key={ item.id } item={ item } />
									) ) }
								</NavigationGroup>
							) }
						</NavigationMenu>
					);
				} ) }
			</Navigation>
		</div>
	);
};

export default compose(
	withSelect( ( select ) => {
		const { getActiveItem, getMenuItems } = select( NAVIGATION_STORE_NAME );

		return {
			activeItem: getActiveItem(),
			menuItems: getMenuItems(),
		};
	} )
)( Container );