1 files changed, 114 insertions, 0 deletions
diff --git a/browser/components/newtab/NewTabPrefsProvider.jsm b/browser/components/newtab/NewTabPrefsProvider.jsm
new file mode 100644
index 000000000..c1d8b4149
--- /dev/null
+++ b/browser/components/newtab/NewTabPrefsProvider.jsm
@@ -0,0 +1,114 @@
+/* global Services, Preferences, EventEmitter, XPCOMUtils */
+/* exported NewTabPrefsProvider */
+
+"use strict";
+
+this.EXPORTED_SYMBOLS = ["NewTabPrefsProvider"];
+
+const {interfaces: Ci, utils: Cu} = Components;
+Cu.import("resource://gre/modules/Services.jsm");
+Cu.import("resource://gre/modules/Preferences.jsm");
+Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+
+XPCOMUtils.defineLazyGetter(this, "EventEmitter", function() {
+  const {EventEmitter} = Cu.import("resource://devtools/shared/event-emitter.js", {});
+  return EventEmitter;
+});
+
+// Supported prefs and data type
+const gPrefsMap = new Map([
+  ["browser.newtabpage.remote", "bool"],
+  ["browser.newtabpage.remote.mode", "str"],
+  ["browser.newtabpage.remote.version", "str"],
+  ["browser.newtabpage.enabled", "bool"],
+  ["browser.newtabpage.enhanced", "bool"],
+  ["browser.newtabpage.introShown", "bool"],
+  ["browser.newtabpage.updateIntroShown", "bool"],
+  ["browser.newtabpage.pinned", "str"],
+  ["browser.newtabpage.blocked", "str"],
+  ["intl.locale.matchOS", "bool"],
+  ["general.useragent.locale", "localized"],
+  ["browser.search.hiddenOneOffs", "str"],
+]);
+
+// prefs that are important for the newtab page
+const gNewtabPagePrefs = new Set([
+  "browser.newtabpage.enabled",
+  "browser.newtabpage.enhanced",
+  "browser.newtabpage.pinned",
+  "browser.newtabpage.blocked",
+  "browser.newtabpage.introShown",
+  "browser.newtabpage.updateIntroShown",
+  "browser.search.hiddenOneOffs",
+]);
+
+let PrefsProvider = function PrefsProvider() {
+  EventEmitter.decorate(this);
+};
+
+PrefsProvider.prototype = {
+
+  observe(subject, topic, data) { // jshint ignore:line
+    if (topic === "nsPref:changed") {
+      if (gPrefsMap.has(data)) {
+        switch (gPrefsMap.get(data)) {
+          case "bool":
+            this.emit(data, Preferences.get(data, false));
+            break;
+          case "str":
+            this.emit(data, Preferences.get(data, ""));
+            break;
+          case "localized":
+            try {
+              this.emit(data, Preferences.get(data, "", Ci.nsIPrefLocalizedString));
+            } catch (e) {
+              this.emit(data, Preferences.get(data, ""));
+            }
+            break;
+          default:
+            this.emit(data);
+            break;
+        }
+      }
+    } else {
+      Cu.reportError(new Error("NewTabPrefsProvider observing unknown topic"));
+    }
+  },
+
+  /*
+   * Return the preferences that are important to the newtab page
+   */
+  get newtabPagePrefs() {
+    let results = {};
+    for (let pref of gNewtabPagePrefs) {
+      results[pref] = Preferences.get(pref, null);
+    }
+    return results;
+  },
+
+  get prefsMap() {
+    return gPrefsMap;
+  },
+
+  init() {
+    for (let pref of gPrefsMap.keys()) {
+      Services.prefs.addObserver(pref, this, false);
+    }
+  },
+
+  uninit() {
+    for (let pref of gPrefsMap.keys()) {
+      Services.prefs.removeObserver(pref, this, false);
+    }
+  }
+};
+
+/**
+ * Singleton that serves as the default new tab pref provider for the grid.
+ */
+const gPrefs = new PrefsProvider();
+
+let NewTabPrefsProvider = {
+  prefs: gPrefs,
+  newtabPagePrefSet: gNewtabPagePrefs,
+};