refui/src/extras/portal.js

The JavaScript framework that refuels your UI projects, across web, native, and embedded

/* Copyright Yukino Song, SudoMaker Ltd.
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 * 	http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

import { signal, onDispose, read } from 'refui/signal'
import { dispose, getCurrentSelf, For, Fn } from 'refui/components'
import { removeFromArr, markStatic } from 'refui/utils'

function dummyRenderer({ item }) {
	return item
}

const outletProps = {
	name: 'Outlet'
}

function createPortal() {
	const nodeArr = []
	const nodes = signal(nodeArr)
	function Inlet(_, ...children) {
		nodeArr.push(children)
		nodes.trigger()
		onDispose(function() {
			removeFromArr(nodeArr, children)
			nodes.trigger()
		})
	}
	function Outlet({ itemRenderer } = {}, fallback) {
		let currentRenderer = null
		let currentViewRenderer = null
		return Fn(outletProps, function() {
			const newRenderer = read(itemRenderer) || dummyRenderer
			if (nodes.value.length) {
				if (newRenderer !== currentRenderer) {
					currentRenderer = newRenderer
					currentViewRenderer = function() {
						return For({ name: null, entries: nodes }, newRenderer)
					}
				}
				return currentViewRenderer
			}
			return fallback
		})
	}

	return [markStatic(Inlet), markStatic(Outlet)]
}

export { createPortal }