166 lines
3.7 KiB
TypeScript

export class Application {
ajaxClass: string
fadeOutClass: string
activeLinkClass: string
content: HTMLElement
loading: HTMLElement
currentPath: string
originalPath: string
lastRequest: XMLHttpRequest
constructor() {
this.currentPath = window.location.pathname
this.originalPath = window.location.pathname
this.ajaxClass = "ajax"
this.activeLinkClass = "active"
this.fadeOutClass = "fade-out"
}
run() {
this.ajaxify()
this.markActiveLinks()
this.loading.classList.add(this.fadeOutClass)
}
find(id: string): HTMLElement {
return document.getElementById(id)
}
get(url: string): Promise<string> {
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, addToHistory: boolean) {
if(this.lastRequest) {
this.lastRequest.abort()
this.lastRequest = null
}
this.currentPath = url
// Start sending a network request
let request = this.get("/_" + url)
let onTransitionEnd = e => {
// Ignore transitions of child elements.
// We only care about the transition event on the content element.
if(e.target !== this.content) {
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 => {
// Add to browser history
if(addToHistory)
history.pushState(url, null, url)
// 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)
this.markActiveLinks()
return request
}
setContent(html: string) {
this.content.innerHTML = html
this.ajaxify(this.content)
this.markActiveLinks(this.content)
}
markActiveLinks(element?: HTMLElement) {
if(element === undefined)
element = document.body
let links = element.querySelectorAll("a")
for(let i = 0; i < links.length; i++) {
let link = links[i]
let href = link.getAttribute("href")
if(href === this.currentPath)
link.classList.add(this.activeLinkClass)
else
link.classList.remove(this.activeLinkClass)
}
}
ajaxify(element?: HTMLElement) {
if(!element)
element = document.body
let links = element.querySelectorAll("." + this.ajaxClass)
for(let i = 0; i < links.length; i++) {
let link = links[i] as HTMLElement
link.classList.remove(this.ajaxClass)
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()
e.stopPropagation()
if(!url || url === self.currentPath)
return
// Load requested page
self.load(url, true)
}
}
}
scrollToTop() {
let parent = this.content
while(parent = parent.parentElement) {
parent.scrollTop = 0
}
}
emit(eventName: string) {
document.dispatchEvent(new Event(eventName, {
"bubbles": true,
"cancelable": true
}))
}
}