const frameHtml = `
Frame
${'<'}script type="module">
let frame = undefined
addEventListener('message', event => {
const isChild = (
frame !== undefined && event.source == frame.contentWindow
)
if (isChild) {
parent.postMessage(event.data, '*')
} else {
let isNew = false
const d = event.data
if (Array.isArray(d) && d[0] === 'srcdoc') {
isNew = frame === undefined
if (isNew) {
frame = document.createElement('iframe')
frame.sandbox = "allow-scripts allow-top-navigation"
}
frame.srcdoc = d[1]
if (isNew) {
document.body.appendChild(frame)
}
} else if (frame !== undefined) {
frame.contentWindow.postMessage(event.data, '*')
}
}
})
${'
`
export class FileGroupPage extends HTMLElement {
constructor() {
super()
this.attachShadow({mode: 'open'})
this.csp = "default-src 'self' 'unsafe-inline' 'unsafe-eval'"
this.viewLoaded = false
this.onceOnLoaded = undefined
}
connectedCallback() {
const style = document.createElement('style')
style.textContent = `
:host {
display: grid;
grid-template-columns: 1fr;
grid-template-rows: 1fr;
grid-template-areas: "main";
flex-direction: column;
align-items: stretch;
}
iframe {
border: none;
margin: 0;
padding: 0;
grid-area: main;
width: 100%;
}
:host(.editing) iframe.view {
display: none;
}
:host(.viewing) iframe.edit {
display: none;
}
`
this.shadowRoot.append(style)
this.initEditFrame()
this.initViewFrame()
this.editing = this.editing
addEventListener('message', this.handleMessage)
}
disconnectedCallback() {
removeEventListener('message', this.handleMessage)
}
initEditFrame() {
const frame = document.createElement('iframe')
frame.classList.add('edit')
if (this.csp !== undefined) {
frame.sandbox = "allow-same-origin allow-scripts allow-top-navigation"
const url = new URL(
'/-/frame', location.href
)
url.searchParams.set('csp', this.csp)
url.searchParams.set('html', frameHtml)
frame.src = url.href
} else {
frame.sandbox = "allow-scripts allow-top-navigation"
frame.srcdoc = frameHtml
}
frame.addEventListener('load', () => {
this.displayEdit()
})
frame.addEventListener('message', message => {
this.handleEditMessage(message)
})
this.editFrame = frame
this.shadowRoot.append(frame)
}
initViewFrame() {
const frame = document.createElement('iframe')
frame.classList.add('view')
if (this.csp !== undefined) {
frame.sandbox = "allow-same-origin allow-scripts allow-top-navigation"
const url = new URL(
'/-/frame', location.href
)
url.searchParams.set('csp', this.csp)
url.searchParams.set('html', frameHtml)
frame.src = url.href
} else {
frame.sandbox = "allow-scripts allow-top-navigation"
frame.srcdoc = frameHtml
}
frame.addEventListener('load', () => {
this.viewLoaded = true
if (this.onceOnLoaded) {
this.onceOnLoaded()
this.onceOnLoaded = undefined
}
})
this.viewFrame = frame
this.shadowRoot.append(frame)
}
displayView(doc) {
const msg = ['srcdoc', doc]
if (this.viewLoaded) {
this.viewFrame.contentWindow.postMessage(
msg, '*'
)
} else {
this.onceOnLoaded = () => {
this.viewFrame.contentWindow.postMessage(
msg, '*'
)
}
}
}
async displayEdit() {
const doc = await this.editorBuild.build()
const msg = ['srcdoc', doc]
this.editFrame.contentWindow.postMessage(
msg, '*'
)
}
handleMessage = event => {
const editWin = this.editFrame?.contentWindow
const viewWin = this.viewFrame?.contentWindow
if (editWin && event.source == editWin) {
this.handleEditMessage(event)
} else if (viewWin && event.source == viewWin) {
this.handleViewMessage(event)
}
}
async handleViewMessage(event) {
}
async handleEditMessage(event) {
if (Array.isArray(event.data)) {
if (event.data[0] === 'ready') {
this.editFrame.contentWindow.postMessage(
['doc', this.body], '*'
)
} else if (event.data[0] === 'html') {
const html = event.data[1]
this.displayView(html)
} else if (event.data[0] === 'save') {
const doc = event.data[1]
this.body = doc
}
}
}
set body(value) {
try {
localStorage.setItem(this.path, value)
} catch (err) {
console.error(err)
}
}
get body() {
try {
return localStorage.getItem(this.path)
} catch (err) {
console.error(err)
return ''
}
}
set editing(value) {
this._editing = value
if (this.shadowRoot.host) {
const classes = this.shadowRoot.host.classList
if (this.editing) {
classes.add('editing')
classes.remove('viewing')
} else {
classes.add('viewing')
classes.remove('editing')
if (this.editFrame) {
this.editFrame.contentWindow.postMessage(
['request-html'], '*'
)
}
}
}
}
get editing() {
return this._editing
}
}