CanvasBlocker/lib/main.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";
	
	const settings = require("./settings");
	const logging = require("./logging");
	const {error, warning, message, notice, verbose, } = logging;
	const lists = require("./lists");
	logging.setPrefix("main script");
	const persistentRndStorage = require("./persistentRndStorage");
	
	message("start of background script");
	message("waiting for settings to be loaded");
	settings.onloaded(function(){
		notice("everything loaded");
		
		persistentRndStorage.init();
		
		message("register non port message listener");
		browser.runtime.onMessage.addListener(function(data){
			notice("got data without port", data);
			var keys = Object.keys(data);
			if (data["canvasBlocker-new-domain-rnd"]){
				persistentRndStorage.setDomainData(
					data["canvasBlocker-new-domain-rnd"].domain,
					data["canvasBlocker-new-domain-rnd"].rnd
				);
				if (keys.length === 1){
					return;
				}
			}
			if (data["canvasBlocker-clear-domain-rnd"]){
				persistentRndStorage.clear();
				if (keys.length === 1){
					return;
				}
			}
			notice("pass the message to the tabs");
			browser.tabs.query({}).then(function(tabs){
				tabs.forEach(function(tab){
					browser.tabs.sendMessage(tab.id, data);
				});
			});
		});
		
		message("register port listener");
		browser.runtime.onConnect.addListener(function(port){
			notice("got port", port);
			verbose("send back the tab id", port.sender.tab.id);
			verbose("send back the persistent random seeds", persistentRndStorage.persistentRnd);
			port.postMessage({
				tabId: port.sender.tab.id,
				persistentRnd: persistentRndStorage.persistentRnd
			});
			var url = new URL(port.sender.url);
			port.onMessage.addListener(function(data){
				if (data.hasOwnProperty("canvasBlocker-notify")){
					if (
						settings.get("showNotifications", url) &&
						!lists.get("ignore").match(url)
					){
						browser.pageAction.show(port.sender.tab.id);
					}
				}
				if (data.hasOwnProperty("canvasBlocker-clear-page-action")){
					notice("Hide page action for tab", port.sender.tab.id);
					browser.pageAction.hide(port.sender.tab.id);
				}
				verbose("got data", data, "from port", port);
			});
		});
		
		message("register storage change event listener");
		
		settings.on("showNotifications", function({newValue}){
			if (!newValue){
				message("notifications were disabled -> hide all page actions");
				browser.tabs.query({}).then(function(tabs){
					tabs.forEach(function(tab){
						browser.pageAction.hide(tab.id);
					});
				});
			}
		});

		if (browser.contentScripts){
			let unregister = function(){};
			let lastRegistering;
			const register = function register(){
				logging.message("Register content script for the settings.");
				logging.verbose("Unregister old content script, if present.");
				unregister();
				var data = {};
				settings.forEach(function(def){
					data[def.name] = def.get();
				});
				lastRegistering = data;
				browser.contentScripts.register({
					matches: ["<all_urls>"],
					matchAboutBlank: true,
					allFrames: true,
					runAt: "document_start",
					js: [{
						code: `(function(){
							const settings = require("./settings");
							settings.init(${JSON.stringify(data)});
						}())`
					}]
				}).then(function(api){
					logging.verbose("Content script registered.");
					if (data !== lastRegistering){
						logging.verbose("Multiple content scripts registered at once. Remove unnecessary one.");
						api.unregister();
					}
					else {
						unregister = api.unregister;
					}
				});
			};
			register();
			settings.on("any", register);
		}
		else {
			logging.error("Old Firefox does not support browser.contentScript.register()");
		}
	});
	
	browser.runtime.onInstalled.addListener(function(){
		message("CanvasBlocker installed");
	});

	message("end");
}());