CanvasBlocker/lib/extension.js

/* 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/. */
(function(){
	"use strict";
	
	let scope;
	if ((typeof exports) !== "undefined"){
		scope = exports;
	}
	else {
		scope = require.register("./extension", {});
	}
	
	const browserAvailable = typeof browser !== "undefined";
	
	scope.inBackgroundScript = !!(
		browserAvailable &&
		browser.extension.getBackgroundPage &&
		browser.extension.getBackgroundPage() === window
	);
	
	scope.getTranslation = browserAvailable? function getTranslation(id){
		return browser.i18n.getMessage(id);
	}: function(id){
		return id;
	};
	
	scope.extensionID = browserAvailable? browser.extension.getURL(""): "extensionID";
	
	scope.inIncognitoContext = browserAvailable? browser.extension.inIncognitoContext: false;
	
	scope.message = {
		on: browserAvailable? function(callback){
			return browser.runtime.onMessage.addListener(callback);
		}: function(){
			return false;
		},
		send: browserAvailable? function(data){
			return browser.runtime.sendMessage(data);
		}: function(){
			return false;
		}
	};
	Object.seal(scope.message);
	
	scope.getWrapped = function getWrapped(obj){
		return obj && (obj.wrappedJSObject || obj);
	};
	
	scope.exportFunctionWithName = function exportFunctionWithName(func, context, name){
		const exportedTry = exportFunction(func, context, {allowCrossOriginArguments: true});
		if (exportedTry.name === name){
			return exportedTry;
		}
		else {
			const wrappedContext = scope.getWrapped(context);
			const options = {
				allowCrossOriginArguments: true,
				defineAs: name
			};
			const oldDescriptor = Object.getOwnPropertyDescriptor(wrappedContext, name);
			const exported = exportFunction(func, context, options);
			if (oldDescriptor){
				Object.defineProperty(wrappedContext, name, oldDescriptor);
			}
			else {
				delete wrappedContext[name];
			}
			return exported;
		}
	};
	
	Object.seal(scope);
}());