A Simple Router based on the HTML5 History
此腳本不應該直接安裝，它是一個供其他腳本使用的函式庫。欲使用本函式庫，請在腳本 metadata 寫上： // @require https://update.greasyfork.org/scripts/558737/1712796/Simple%20Router.js
// ==UserScript==
// @name Simple Router
// @description A Simple Router based on the HTML5 History
// @namespace https://github.com/dzist
// @version 0.0.1
// @author Dylan Zhang
// ==/UserScript==
class SimpleRouter {
constructor() {
this.routes = new Map()
this.beforeCbs = new Set()
this.currentMatcher = null
this.overrideHistory()
}
overrideHistory() {
const { history } = window
const hook = () => this.handle()
const override = (fn) => {
return (...args) => {
const result = fn.apply(history, args)
hook()
return result
}
}
history.pushState = override(history.pushState)
history.replaceState = override(history.replaceState)
window.addEventListener('popstate', hook)
}
// use(path: string | () => void, cb?: () => void): Router
use(path, cb) {
let matcher
if (typeof path === 'string') {
matcher = this.getMatcher(path)
if (!matcher) {
matcher = {
path,
regexp: new RegExp(`^${path}$`)
}
}
this.currentMatcher = matcher
}
if (typeof path === 'function') {
cb = path
matcher = this.currentMatcher
}
if (cb) {
const cbs = this.routes.get(matcher)
cbs
? cbs.add(cb)
: this.routes.set(matcher, new Set([cb]))
}
return this
}
// disuse(path: string, cb?: () => void): boolean
disuse(path, cb) {
const matcher = this.getMatcher(path)
if (!matcher) return true
const cbs = this.routes.get(matcher)
if (!cbs) return true
if (!cb) {
cbs.clear()
return true
}
return cbs.delete(cb)
}
getMatcher(path) {
return this.routes
.keys()
.find(m => m.path === path)
}
once(path, cb) {
if (typeof path === 'string' && !cb) {
throw new Error(
`It is not the path, but the corresponding function that can only be used once.` +
`Please specify a callback function for the path: ${path}\n` +
`such as once('/', () => {...})`
)
}
if (typeof path === 'function') {
cb = path
path = this.currentMatcher?.path
if (!path) {
throw new Error(
`Please specify the path for the callback function first:\n${cb}\n` +
`such as use('/') or once('/', () => {...})`
)
}
}
const fnOnce = (...args) => {
cb(...args)
this.disuse(path, fnOnce)
}
return this.use(path, fnOnce)
}
before(cb) {
this.beforeCbs.add(cb)
return this
}
beforeOnce(cb) {
const fnOnce = (...args) => {
cb(...args)
this.beforeCbs.delete(fnOnce)
}
return this.before(fnOnce)
}
handle(path = this.path) {
this.beforeCbs.forEach(cb => cb())
for(const [matcher, cbs] of this.routes) {
if (matcher.regexp.test(path)) {
cbs.forEach(cb => cb())
break
}
}
}
get path() {
const segments = location.pathname.split('/')
const path = segments[1]
return path ? `/${path}` : '/'
}
}