| // Copyright 2019 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| /** |
| * @fileoverview This file is not auto-generated from cr.js, because it's a |
| * special case. cr.js holds a lot of functionality that is unnecessary in the |
| * JS Module world, and auto-generating cr.m.js would require adding a lot of |
| * logic in js_modulizer.py only to address the cr.js case, which is not worth |
| * it. |
| */ |
| import {assert} from './assert.m.js'; |
| import {PromiseResolver} from './promise_resolver.m.js'; |
| |
| /** @typedef {{eventName: string, uid: number}} */ |
| export let WebUIListener; |
| |
| /** |
| * Counter for use with createUid |
| * @type {number} |
| */ |
| let uidCounter = 1; |
| |
| /** |
| * @return {number} A new unique ID. |
| */ |
| function createUid() { |
| return uidCounter++; |
| } |
| |
| /** |
| * Dispatches a simple event on an event target. |
| * @param {!EventTarget} target The event target to dispatch the event on. |
| * @param {string} type The type of the event. |
| * @param {boolean=} opt_bubbles Whether the event bubbles or not. |
| * @param {boolean=} opt_cancelable Whether the default action of the event |
| * can be prevented. Default is true. |
| * @return {boolean} If any of the listeners called {@code preventDefault} |
| * during the dispatch this will return false. |
| */ |
| export function dispatchSimpleEvent(target, type, opt_bubbles, opt_cancelable) { |
| const e = new Event(type, { |
| bubbles: opt_bubbles, |
| cancelable: opt_cancelable === undefined || opt_cancelable |
| }); |
| return target.dispatchEvent(e); |
| } |
| |
| /** |
| * Adds a {@code getInstance} static method that always return the same |
| * instance object. |
| * @param {!Function} ctor The constructor for the class to add the static |
| * method to. |
| */ |
| export function addSingletonGetter(ctor) { |
| ctor.getInstance = function() { |
| return ctor.instance_ || (ctor.instance_ = new ctor()); |
| }; |
| } |
| |
| /** |
| * Fires a property change event on the target. |
| * @param {!EventTarget} target The target to dispatch the event on. |
| * @param {string} propertyName The name of the property that changed. |
| * @param {*} newValue The new value for the property. |
| * @param {*} oldValue The old value for the property. |
| */ |
| export function dispatchPropertyChange( |
| target, propertyName, newValue, oldValue) { |
| const e = new Event(propertyName + 'Change'); |
| e.propertyName = propertyName; |
| e.newValue = newValue; |
| e.oldValue = oldValue; |
| target.dispatchEvent(e); |
| } |
| |
| |
| /** |
| * The mapping used by the sendWithPromise mechanism to tie the Promise |
| * returned to callers with the corresponding WebUI response. The mapping is |
| * from ID to the PromiseResolver helper; the ID is generated by |
| * sendWithPromise and is unique across all invocations of said method. |
| * @type {!Object<!PromiseResolver>} |
| */ |
| const chromeSendResolverMap = {}; |
| |
| /** |
| * The named method the WebUI handler calls directly in response to a |
| * chrome.send call that expects a response. The handler requires no knowledge |
| * of the specific name of this method, as the name is passed to the handler |
| * as the first argument in the arguments list of chrome.send. The handler |
| * must pass the ID, also sent via the chrome.send arguments list, as the |
| * first argument of the JS invocation; additionally, the handler may |
| * supply any number of other arguments that will be included in the response. |
| * @param {string} id The unique ID identifying the Promise this response is |
| * tied to. |
| * @param {boolean} isSuccess Whether the request was successful. |
| * @param {*} response The response as sent from C++. |
| */ |
| export function webUIResponse(id, isSuccess, response) { |
| const resolver = chromeSendResolverMap[id]; |
| delete chromeSendResolverMap[id]; |
| |
| if (isSuccess) { |
| resolver.resolve(response); |
| } else { |
| resolver.reject(response); |
| } |
| } |
| |
| /** |
| * A variation of chrome.send, suitable for messages that expect a single |
| * response from C++. |
| * @param {string} methodName The name of the WebUI handler API. |
| * @param {...*} var_args Variable number of arguments to be forwarded to the |
| * C++ call. |
| * @return {!Promise} |
| */ |
| export function sendWithPromise(methodName, var_args) { |
| const args = Array.prototype.slice.call(arguments, 1); |
| const promiseResolver = new PromiseResolver(); |
| const id = methodName + '_' + createUid(); |
| chromeSendResolverMap[id] = promiseResolver; |
| chrome.send(methodName, [id].concat(args)); |
| return promiseResolver.promise; |
| } |
| |
| /** |
| * A map of maps associating event names with listeners. The 2nd level map |
| * associates a listener ID with the callback function, such that individual |
| * listeners can be removed from an event without affecting other listeners of |
| * the same event. |
| * @type {!Object<!Object<!Function>>} |
| */ |
| const webUIListenerMap = {}; |
| |
| /** |
| * The named method the WebUI handler calls directly when an event occurs. |
| * The WebUI handler must supply the name of the event as the first argument |
| * of the JS invocation; additionally, the handler may supply any number of |
| * other arguments that will be forwarded to the listener callbacks. |
| * @param {string} event The name of the event that has occurred. |
| * @param {...*} var_args Additional arguments passed from C++. |
| */ |
| export function webUIListenerCallback(event, var_args) { |
| const eventListenersMap = webUIListenerMap[event]; |
| if (!eventListenersMap) { |
| // C++ event sent for an event that has no listeners. |
| // TODO(dpapad): Should a warning be displayed here? |
| return; |
| } |
| |
| const args = Array.prototype.slice.call(arguments, 1); |
| for (const listenerId in eventListenersMap) { |
| eventListenersMap[listenerId].apply(null, args); |
| } |
| } |
| |
| /** |
| * Registers a listener for an event fired from WebUI handlers. Any number of |
| * listeners may register for a single event. |
| * @param {string} eventName The event to listen to. |
| * @param {!Function} callback The callback run when the event is fired. |
| * @return {!WebUIListener} An object to be used for removing a listener via |
| * cr.removeWebUIListener. Should be treated as read-only. |
| */ |
| export function addWebUIListener(eventName, callback) { |
| webUIListenerMap[eventName] = webUIListenerMap[eventName] || {}; |
| const uid = createUid(); |
| webUIListenerMap[eventName][uid] = callback; |
| return {eventName: eventName, uid: uid}; |
| } |
| |
| /** |
| * Removes a listener. Does nothing if the specified listener is not found. |
| * @param {!WebUIListener} listener The listener to be removed (as returned by |
| * addWebUIListener). |
| * @return {boolean} Whether the given listener was found and actually |
| * removed. |
| */ |
| export function removeWebUIListener(listener) { |
| const listenerExists = webUIListenerMap[listener.eventName] && |
| webUIListenerMap[listener.eventName][listener.uid]; |
| if (listenerExists) { |
| delete webUIListenerMap[listener.eventName][listener.uid]; |
| return true; |
| } |
| return false; |
| } |
| |
| // Globally expose functions that must be called from C++. |
| window.cr = window.cr || {}; |
| assert(!window.cr.webUIResponse); |
| assert(!window.cr.webUIListenerCallback); |
| window.cr.webUIResponse = webUIResponse; |
| window.cr.webUIListenerCallback = webUIListenerCallback; |
| |
| /** Whether we are using a Mac or not. */ |
| export const isMac = /Mac/.test(navigator.platform); |
| |
| /** Whether this is on the Windows platform or not. */ |
| export const isWindows = /Win/.test(navigator.platform); |
| |
| /** Whether this is the ChromeOS/ash web browser. */ |
| export const isChromeOS = (() => { |
| let returnValue = false; |
| // <if expr="chromeos"> |
| returnValue = true; |
| // </if> |
| return returnValue; |
| })(); |
| |
| /** Whether this is the ChromeOS/Lacros web browser. */ |
| export const isLacros = (() => { |
| let returnValue = false; |
| // <if expr="lacros"> |
| returnValue = true; |
| // </if> |
| return returnValue; |
| })(); |
| |
| /** Whether this is on vanilla Linux (not chromeOS). */ |
| export const isLinux = /Linux/.test(navigator.userAgent); |
| |
| /** Whether this is on Android. */ |
| export const isAndroid = /Android/.test(navigator.userAgent); |
| |
| /** Whether this is on iOS. */ |
| export const isIOS = /CriOS/.test(navigator.userAgent); |