michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: "use strict";
michael@0: 
michael@0: // This module provides temporary shim until Bug 843901 is shipped.
michael@0: // It basically registers tab event listeners on all windows that get
michael@0: // opened and forwards them through observer notifications.
michael@0: 
michael@0: module.metadata = {
michael@0:   "stability": "experimental"
michael@0: };
michael@0: 
michael@0: const { Ci } = require("chrome");
michael@0: const { windows, isInteractive } = require("../window/utils");
michael@0: const { events } = require("../browser/events");
michael@0: const { open } = require("../event/dom");
michael@0: const { filter, map, merge, expand } = require("../event/utils");
michael@0: const isFennec = require("sdk/system/xul-app").is("Fennec");
michael@0: 
michael@0: // Module provides event stream (in nodejs style) that emits data events
michael@0: // for all the tab events that happen in running firefox. At the moment
michael@0: // it does it by registering listeners on all browser windows and then
michael@0: // forwarding events when they occur to a stream. This will become obsolete
michael@0: // once Bug 843901 is fixed, and we'll just leverage observer notifications.
michael@0: 
michael@0: // Set of tab events that this module going to aggregate and expose.
michael@0: const TYPES = ["TabOpen","TabClose","TabSelect","TabMove","TabPinned",
michael@0:                "TabUnpinned"];
michael@0: 
michael@0: // Utility function that given a browser `window` returns stream of above
michael@0: // defined tab events for all tabs on the given window.
michael@0: function tabEventsFor(window) {
michael@0:   // Map supported event types to a streams of those events on the given
michael@0:   // `window` and than merge these streams into single form stream off
michael@0:   // all events.
michael@0:   let channels = TYPES.map(function(type) open(window, type));
michael@0:   return merge(channels);
michael@0: }
michael@0: 
michael@0: // Filter DOMContentLoaded events from all the browser events.
michael@0: let readyEvents = filter(events, function(e) e.type === "DOMContentLoaded");
michael@0: // Map DOMContentLoaded events to it's target browser windows.
michael@0: let futureWindows = map(readyEvents, function(e) e.target);
michael@0: // Expand all browsers that will become interactive to supported tab events
michael@0: // on these windows. Result will be a tab events from all tabs of all windows
michael@0: // that will become interactive.
michael@0: let eventsFromFuture = expand(futureWindows, tabEventsFor);
michael@0: 
michael@0: // Above covers only windows that will become interactive in a future, but some
michael@0: // windows may already be interactive so we pick those and expand to supported
michael@0: // tab events for them too.
michael@0: let interactiveWindows = windows("navigator:browser", { includePrivate: true }).
michael@0:                          filter(isInteractive);
michael@0: let eventsFromInteractive = merge(interactiveWindows.map(tabEventsFor));
michael@0: 
michael@0: 
michael@0: // Finally merge stream of tab events from future windows and current windows
michael@0: // to cover all tab events on all windows that will open.
michael@0: let allEvents = merge([eventsFromInteractive, eventsFromFuture]);
michael@0: 
michael@0: // Map events to Fennec format if necessary
michael@0: exports.events = map(allEvents, function (event) {
michael@0:   return !isFennec ? event : {
michael@0:     type: event.type,
michael@0:     target: event.target.ownerDocument.defaultView.BrowserApp
michael@0:             .getTabForBrowser(event.target)
michael@0:   };
michael@0: });