/* vim: set ts=2 sw=2 sts=2 et tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at
http://mozilla.org/MPL/2.0/. */
export class UAWidgetsChild extends JSWindowActorChild {
constructor() {
super();
this.widgets = new WeakMap();
this.prefsCache = new Map();
this.observedPrefs = [];
// Bug 1570744 - JSWindowActorChild's cannot be used as nsIObserver's
// directly, so we create a new function here instead to act as our
// nsIObserver, which forwards the notification to the observe method.
this.observerFunction = (subject, topic, data) => {
this.observe(subject, topic, data);
};
}
didDestroy() {
for (let pref in this.observedPrefs) {
Services.prefs.removeObserver(pref, this.observerFunction);
}
}
unwrap(obj) {
return Cu.isXrayWrapper(obj) ? obj.wrappedJSObject : obj;
}
handleEvent(aEvent) {
switch (aEvent.type) {
case "UAWidgetSetupOrChange":
this.setupOrNotifyWidget(aEvent.target);
break;
case "UAWidgetTeardown":
this.teardownWidget(aEvent.target);
break;
}
}
setupOrNotifyWidget(aElement) {
if (!this.widgets.has(aElement)) {
this.setupWidget(aElement);
return;
}
let { widget } = this.widgets.get(aElement);
if (typeof widget.onchange == "function") {
if (
this.unwrap(aElement.openOrClosedShadowRoot) !=
this.unwrap(widget.shadowRoot)
) {
console.error(
"Getting a UAWidgetSetupOrChange event without the ShadowRoot. " +
"Torn down already?"
);
return;
}
try {
widget.onchange();
} catch (ex) {
console.error(ex);
}
}
}
setupWidget(aElement) {
let uri;
let widgetName;
// Use prefKeys to optionally send a list of preferences to forward to
// the UAWidget. The UAWidget will receive those preferences as key-value
// pairs as the second argument to its constructor. Updates to those prefs
// can be observed by implementing an optional onPrefChange method for the
// UAWidget that receives the changed pref name as the first argument, and
// the updated value as the second.
let prefKeys = [];
switch (aElement.localName) {
case "video":
case "audio":
uri = "chrome://global/content/elements/videocontrols.js";
widgetName = "VideoControlsWidget";
prefKeys = [
"media.videocontrols.picture-in-picture.enabled",
"media.videocontrols.picture-in-picture.video-toggle.enabled",
"media.videocontrols.picture-in-picture.video-toggle.always-show",
"media.videocontrols.picture-in-picture.video-toggle.min-video-secs",
"media.videocontrols.picture-in-picture.video-toggle.position",
"media.videocontrols.picture-in-picture.video-toggle.has-used",
"media.videocontrols.keyboard-tab-to-all-controls",
"media.videocontrols.picture-in-picture.respect-disablePictureInPicture",
];
break;
case "input":
uri = "chrome://global/content/elements/datetimebox.js";
widgetName = "DateTimeBoxWidget";
prefKeys = ["privacy.resistFingerprinting"];
break;
case "marquee":
uri = "chrome://global/content/elements/marquee.js";
widgetName = "MarqueeWidget";
break;
case "img":
uri = "chrome://global/content/elements/textrecognition.js";
widgetName = "TextRecognitionWidget";
}
if (!uri || !widgetName) {
console.error(
"Getting a UAWidgetSetupOrChange event on undefined element."
);
return;
}
let shadowRoot = aElement.openOrClosedShadowRoot;
if (!shadowRoot) {
console.error(
"Getting a UAWidgetSetupOrChange event without the Shadow Root. " +
"Torn down already?"
);
return;
}
let isSystemPrincipal = aElement.nodePrincipal.isSystemPrincipal;
let sandbox = isSystemPrincipal
? Object.create(null)
: Cu.getUAWidgetScope(aElement.nodePrincipal);
if (!sandbox[widgetName]) {
Services.scriptloader.loadSubScript(uri, sandbox);
}
let prefs = Cu.cloneInto(
this.getPrefsForUAWidget(widgetName, prefKeys),
sandbox
);
let widget = new sandbox[widgetName](shadowRoot, prefs);
if (!isSystemPrincipal) {
widget = widget.wrappedJSObject;
}
if (this.unwrap(widget.shadowRoot) != this.unwrap(shadowRoot)) {
console.error("Widgets should expose their shadow root.");
}
this.widgets.set(aElement, { widget, widgetName });
try {
widget.onsetup();
} catch (ex) {
console.error(ex);
}
}
teardownWidget(aElement) {
if (!this.widgets.has(aElement)) {
return;
}
let { widget } = this.widgets.get(aElement);
if (typeof widget.teardown == "function") {
try {
widget.teardown();
} catch (ex) {
console.error(ex);
}
}
this.widgets.delete(aElement);
}
getPrefsForUAWidget(aWidgetName, aPrefKeys) {
let result = this.prefsCache.get(aWidgetName);
if (result) {
return result;
}
result = {};
for (let key of aPrefKeys) {
result[key] = this.getPref(key);
this.observePref(key);
}
this.prefsCache.set(aWidgetName, result);
return result;
}
observePref(prefKey) {
Services.prefs.addObserver(prefKey, this.observerFunction);
this.observedPrefs.push(prefKey);
}
getPref(prefKey) {
switch (Services.prefs.getPrefType(prefKey)) {
case Ci.nsIPrefBranch.PREF_BOOL: {
return Services.prefs.getBoolPref(prefKey);
}
case Ci.nsIPrefBranch.PREF_INT: {
return Services.prefs.getIntPref(prefKey);
}
case Ci.nsIPrefBranch.PREF_STRING: {
return Services.prefs.getStringPref(prefKey);
}
}
return undefined;
}
observe(subject, topic, data) {
if (topic == "nsPref:changed") {
for (let [widgetName, prefCache] of this.prefsCache) {
if (prefCache.hasOwnProperty(data)) {
let newValue = this.getPref(data);
prefCache[data] = newValue;
this.notifyWidgetsOnPrefChange(widgetName, data, newValue);
}
}
}
}
notifyWidgetsOnPrefChange(nameOfWidgetToNotify, prefKey, newValue) {
let elements = ChromeUtils.nondeterministicGetWeakMapKeys(this.widgets);
for (let element of elements) {
if (!Cu.isDeadWrapper(element) && element.isConnected) {
let { widgetName, widget } = this.widgets.get(element);
if (widgetName == nameOfWidgetToNotify) {
if (typeof widget.onPrefChange == "function") {
try {
widget.onPrefChange(prefKey, newValue);
} catch (ex) {
console.error(ex);
}
}
}
}
}
}
}
