gecko-dev/toolkit/modules/DirectoryLinksProvider.jsm

205 строки
5.4 KiB
JavaScript

/* 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";
this.EXPORTED_SYMBOLS = ["DirectoryLinksProvider"];
const Ci = Components.interfaces;
const Cc = Components.classes;
const Cu = Components.utils;
Cu.import("resource://gre/modules/XPCOMUtils.jsm");
Cu.import("resource://gre/modules/Services.jsm");
XPCOMUtils.defineLazyModuleGetter(this, "NetUtil",
"resource://gre/modules/NetUtil.jsm");
/**
* Gets the currently selected locale for display.
* @return the selected locale or "en-US" if none is selected
*/
function getLocale() {
let matchOS;
try {
matchOS = Services.prefs.getBoolPref(PREF_MATCH_OS_LOCALE);
}
catch (e) {}
if (matchOS) {
return Services.locale.getLocaleComponentForUserAgent();
}
try {
let locale = Services.prefs.getComplexValue(PREF_SELECTED_LOCALE,
Ci.nsIPrefLocalizedString);
if (locale) {
return locale.data;
}
}
catch (e) {}
try {
return Services.prefs.getCharPref(PREF_SELECTED_LOCALE);
}
catch (e) {}
return "en-US";
}
// The preference that tells whether to match the OS locale
const PREF_MATCH_OS_LOCALE = "intl.locale.matchOS";
// The preference that tells what locale the user selected
const PREF_SELECTED_LOCALE = "general.useragent.locale";
// The preference that tells where to obtain directory links
const PREF_DIRECTORY_SOURCE = "browser.newtabpage.directorySource";
// The frecency of a directory link
const DIRECTORY_FRECENCY = 1000;
const LINK_TYPES = Object.freeze([
"sponsored",
"affiliate",
"organic",
]);
/**
* Singleton that serves as the provider of directory links.
* Directory links are a hard-coded set of links shown if a user's link
* inventory is empty.
*/
let DirectoryLinksProvider = {
__linksURL: null,
_observers: [],
get _prefs() Object.freeze({
linksURL: PREF_DIRECTORY_SOURCE,
matchOSLocale: PREF_MATCH_OS_LOCALE,
prefSelectedLocale: PREF_SELECTED_LOCALE,
}),
get _linksURL() {
if (!this.__linksURL) {
try {
this.__linksURL = Services.prefs.getCharPref(this._prefs["linksURL"]);
}
catch (e) {
Cu.reportError("Error fetching directory links url from prefs: " + e);
}
}
return this.__linksURL;
},
get linkTypes() LINK_TYPES,
observe: function DirectoryLinksProvider_observe(aSubject, aTopic, aData) {
if (aTopic == "nsPref:changed") {
if (aData == this._prefs["linksURL"]) {
delete this.__linksURL;
}
this._callObservers("onManyLinksChanged");
}
},
_addPrefsObserver: function DirectoryLinksProvider_addObserver() {
for (let pref in this._prefs) {
let prefName = this._prefs[pref];
Services.prefs.addObserver(prefName, this, false);
}
},
_removePrefsObserver: function DirectoryLinksProvider_removeObserver() {
for (let pref in this._prefs) {
let prefName = this._prefs[pref];
Services.prefs.removeObserver(prefName, this);
}
},
/**
* Fetches the current set of directory links.
* @param aCallback a callback that is provided a set of links.
*/
_fetchLinks: function DirectoryLinksProvider_fetchLinks(aCallback) {
try {
NetUtil.asyncFetch(this._linksURL, (aInputStream, aResult, aRequest) => {
let output;
if (Components.isSuccessCode(aResult)) {
try {
let json = NetUtil.readInputStreamToString(aInputStream,
aInputStream.available(),
{charset: "UTF-8"});
let locale = getLocale();
output = JSON.parse(json)[locale];
}
catch (e) {
Cu.reportError(e);
}
}
else {
Cu.reportError(new Error("the fetch of " + this._linksURL + "was unsuccessful"));
}
aCallback(output || []);
});
}
catch (e) {
Cu.reportError(e);
aCallback([]);
}
},
/**
* Gets the current set of directory links.
* @param aCallback The function that the array of links is passed to.
*/
getLinks: function DirectoryLinksProvider_getLinks(aCallback) {
this._fetchLinks(rawLinks => {
// all directory links have a frecency of DIRECTORY_FRECENCY
aCallback(rawLinks.map((link, position) => {
link.frecency = DIRECTORY_FRECENCY;
link.lastVisitDate = rawLinks.length - position;
return link;
}));
});
},
init: function DirectoryLinksProvider_init() {
this._addPrefsObserver();
},
/**
* Return the object to its pre-init state
*/
reset: function DirectoryLinksProvider_reset() {
delete this.__linksURL;
this._removePrefsObserver();
this._removeObservers();
},
addObserver: function DirectoryLinksProvider_addObserver(aObserver) {
this._observers.push(aObserver);
},
_callObservers: function DirectoryLinksProvider__callObservers(aMethodName, aArg) {
for (let obs of this._observers) {
if (typeof(obs[aMethodName]) == "function") {
try {
obs[aMethodName](this, aArg);
} catch (err) {
Cu.reportError(err);
}
}
}
},
_removeObservers: function() {
while (this._observers.length) {
this._observers.pop();
}
}
};