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/* 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/. */
"use strict";
const { ActivityStreamMessageChannel } = ChromeUtils.import(
);
const { ActivityStreamStorage } = ChromeUtils.import(
);
const { Prefs } = ChromeUtils.import(
);
const { reducers } = ChromeUtils.import(
);
const { redux } = ChromeUtils.import(
);
/**
* Store - This has a similar structure to a redux store, but includes some extra
* functionality to allow for routing of actions between the Main processes
* and child processes via a ActivityStreamMessageChannel.
* It also accepts an array of "Feeds" on inititalization, which
* can listen for any action that is dispatched through the store.
*/
this.Store = class Store {
/**
* constructor - The redux store and message manager are created here,
* but no listeners are added until "init" is called.
*/
constructor() {
this._middleware = this._middleware.bind(this);
// Bind each redux method so we can call it directly from the Store. E.g.,
// store.dispatch() will call store._store.dispatch();
for (const method of ["dispatch", "getState", "subscribe"]) {
this[method] = (...args) => this._store[method](...args);
}
this.feeds = new Map();
this._prefs = new Prefs();
this._messageChannel = new ActivityStreamMessageChannel({
dispatch: this.dispatch,
});
this._store = redux.createStore(
redux.combineReducers(reducers),
redux.applyMiddleware(this._middleware, this._messageChannel.middleware)
);
this.storage = null;
}
/**
* _middleware - This is redux middleware consumed by redux.createStore.
* it calls each feed's .onAction method, if one
* is defined.
*/
_middleware() {
return next => action => {
next(action);
for (const store of this.feeds.values()) {
if (store.onAction) {
store.onAction(action);
}
}
};
}
/**
* initFeed - Initializes a feed by calling its constructor function
*
* @param {string} feedName The name of a feed, as defined in the object
* passed to Store.init
* @param {Action} initAction An optional action to initialize the feed
*/
initFeed(feedName, initAction) {
const feed = this._feedFactories.get(feedName)();
feed.store = this;
this.feeds.set(feedName, feed);
if (initAction && feed.onAction) {
feed.onAction(initAction);
}
}
/**
* uninitFeed - Removes a feed and calls its uninit function if defined
*
* @param {string} feedName The name of a feed, as defined in the object
* passed to Store.init
* @param {Action} uninitAction An optional action to uninitialize the feed
*/
uninitFeed(feedName, uninitAction) {
const feed = this.feeds.get(feedName);
if (!feed) {
return;
}
if (uninitAction && feed.onAction) {
feed.onAction(uninitAction);
}
this.feeds.delete(feedName);
}
/**
* onPrefChanged - Listener for handling feed changes.
*/
onPrefChanged(name, value) {
if (this._feedFactories.has(name)) {
if (value) {
this.initFeed(name, this._initAction);
} else {
this.uninitFeed(name, this._uninitAction);
}
}
}
/**
* init - Initializes the ActivityStreamMessageChannel channel, and adds feeds.
*
* Note that it intentionally initializes the TelemetryFeed first so that the
* addon is able to report the init errors from other feeds.
*
* @param {Map} feedFactories A Map of feeds with the name of the pref for
* the feed as the key and a function that
* constructs an instance of the feed.
* @param {Action} initAction An optional action that will be dispatched
* to feeds when they're created.
* @param {Action} uninitAction An optional action for when feeds uninit.
*/
async init(feedFactories, initAction, uninitAction) {
this._feedFactories = feedFactories;
this._initAction = initAction;
this._uninitAction = uninitAction;
const telemetryKey = "feeds.telemetry";
if (feedFactories.has(telemetryKey) && this._prefs.get(telemetryKey)) {
this.initFeed(telemetryKey);
}
await this._initIndexedDB(telemetryKey);
for (const pref of feedFactories.keys()) {
if (pref !== telemetryKey && this._prefs.get(pref)) {
this.initFeed(pref);
}
}
this._prefs.observeBranch(this);
this._messageChannel.createChannel();
// Dispatch an initial action after all enabled feeds are ready
if (initAction) {
this.dispatch(initAction);
}
// Dispatch NEW_TAB_INIT/NEW_TAB_LOAD events after INIT event.
this._messageChannel.simulateMessagesForExistingTabs();
}
async _initIndexedDB(telemetryKey) {
this.dbStorage = new ActivityStreamStorage({
storeNames: ["sectionPrefs", "snippets"],
telemetry: this.feeds.get(telemetryKey),
});
// Accessing the db causes the object stores to be created / migrated.
// This needs to happen before other instances try to access the db, which
// would update only a subset of the stores to the latest version.
try {
await this.dbStorage.db; // eslint-disable-line no-unused-expressions
} catch (e) {
this.dbStorage.telemetry = null;
}
}
/**
* uninit - Uninitalizes each feed, clears them, and destroys the message
* manager channel.
*
* @return {type} description
*/
uninit() {
if (this._uninitAction) {
this.dispatch(this._uninitAction);
}
this._prefs.ignoreBranch(this);
this.feeds.clear();
this._feedFactories = null;
this._messageChannel.destroyChannel();
}
};
const EXPORTED_SYMBOLS = ["Store"];