2018-03-29 11:36:54 +02:00

212 lines
4.6 KiB
TypeScript

import { Diff } from "./Diff"
class LoadOptions {
addToHistory?: boolean
forceReload?: boolean
}
export class Application {
fadeOutClass: string
activeLinkClass: string
content: HTMLElement
loading: HTMLElement
currentPath: string
originalPath: string
lastRequest: XMLHttpRequest | null
constructor() {
this.currentPath = window.location.pathname
this.originalPath = window.location.pathname
this.activeLinkClass = "active"
this.fadeOutClass = "fade-out"
}
init() {
document.addEventListener("DOMContentLoaded", () => {
let links = document.getElementsByTagName("a")
this.markActiveLinks(links)
this.ajaxify(links)
})
}
find(id: string): HTMLElement | null {
return document.getElementById(id)
}
get(url: string): Promise<string> {
// return fetch(url, {
// credentials: "same-origin"
// }).then(response => response.text())
if(this.lastRequest) {
this.lastRequest.abort()
this.lastRequest = null
}
return new Promise((resolve, reject) => {
let request = new XMLHttpRequest()
request.onerror = () => reject(new Error("You are either offline or the requested page doesn't exist."))
request.ontimeout = () => reject(new Error("The page took too much time to respond."))
request.onload = () => {
if(request.status < 200 || request.status >= 400)
reject(request.responseText)
else
resolve(request.responseText)
}
request.open("GET", url, true)
request.send()
this.lastRequest = request
})
}
load(url: string, options?: LoadOptions) {
// Remove protocol and hostname if it was specified
if(url.startsWith(location.origin)) {
url = url.substr(location.origin.length)
}
// Start sending a network request
let request = this.get("/_" + url).catch(error => error)
// Parse options
if(!options) {
options = new LoadOptions()
}
if(options.addToHistory === undefined) {
options.addToHistory = true
}
// Set current path
this.currentPath = url
// Add to browser history
if(options.addToHistory) {
history.pushState(url, "", url)
}
// Mark active links
this.markActiveLinks()
let onTransitionEnd = (e: Event) => {
// Ignore transitions of child elements.
// We only care about the transition event on the content element.
if(e.target !== this.content) {
return
}
// Outdated response.
if(this.currentPath !== url) {
return
}
// Remove listener after we finally got the correct event.
this.content.removeEventListener("transitionend", onTransitionEnd)
// Wait for the network request to end.
request.then(html => {
// Set content
this.setContent(html)
this.scrollToTop()
// Fade animations
this.content.classList.remove(this.fadeOutClass)
this.loading.classList.add(this.fadeOutClass)
// Send DOMContentLoaded Event
this.emit("DOMContentLoaded")
})
}
this.content.addEventListener("transitionend", onTransitionEnd)
this.content.classList.add(this.fadeOutClass)
this.loading.classList.remove(this.fadeOutClass)
return request
}
setContent(html: string) {
this.content.innerHTML = html
}
markActiveLinks(links?: NodeListOf<HTMLAnchorElement>) {
if(!links) {
links = document.getElementsByTagName("a")
}
for(let i = 0; i < links.length; i++) {
let link = links[i]
Diff.mutations.queue(() => {
if(link.getAttribute("href") === this.currentPath) {
link.classList.add(this.activeLinkClass)
} else {
link.classList.remove(this.activeLinkClass)
}
})
}
}
ajaxify(links?: NodeListOf<HTMLAnchorElement>) {
if(!links) {
links = document.getElementsByTagName("a")
}
for(let i = 0; i < links.length; i++) {
let link = links[i] as HTMLAnchorElement
// Don't ajaxify links to a different host
if(link.hostname !== window.location.hostname) {
if(!link.target) {
link.target = "_blank"
}
continue
}
// Don't ajaxify invalid links, links with a target or links that disable ajax specifically
if(link.href === "" || link.href.includes("#") || link.target.length > 0 || link.dataset.ajax === "false") {
continue
}
let self = this
link.onclick = function(e) {
// Middle mouse button should have standard behaviour
if(e.which === 2) {
return
}
let url = this.getAttribute("href")
e.preventDefault()
if(!url || url === self.currentPath) {
return
}
// Load requested page
self.load(url)
}
}
}
scrollToTop() {
let parent : HTMLElement | null = this.content
Diff.mutations.queue(() => {
while(parent = parent.parentElement) {
parent.scrollTop = 0
}
})
}
emit(eventName: string) {
document.dispatchEvent(new Event(eventName))
}
}