Issue 2040 - Replaced localStorage with chrome.storage.local

lib/prefs.js

Index: lib/prefs.js
===================================================================
--- a/lib/prefs.js
+++ b/lib/prefs.js
@@ -15,81 +15,11 @@
  * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-//
-// The values are hardcoded for now.
-//
+const keyPrefix = "pref:";
 
-let defaults = Object.create(null);
-defaults.enabled = true;
-defaults.data_directory = "";
-defaults.patternsbackups = 5;
-defaults.patternsbackupinterval = 24;
-defaults.savestats = false;
-defaults.privateBrowsing = false;
-defaults.subscriptions_fallbackerrors = 5;
-defaults.subscriptions_fallbackurl = "https://adblockplus.org/getSubscription?version=%VERSION%&url=%SUBSCRIPTION%&downloadURL=%URL%&error=%ERROR%&channelStatus=%CHANNELSTATUS%&responseStatus=%RESPONSESTATUS%";
-defaults.subscriptions_autoupdate = true;
-defaults.subscriptions_exceptionsurl = "https://easylist-downloads.adblockplus.org/exceptionrules.txt";
-defaults.subscriptions_antiadblockurl = "https://easylist-downloads.adblockplus.org/antiadblockfilters.txt";
-defaults.documentation_link = "https://adblockplus.org/redirect?link=%LINK%&lang=%LANG%";
-defaults.notificationdata = {};
-defaults.notificationurl = "https://notification.adblockplus.org/notification.json";
-defaults.stats_total = {};
-defaults.show_statsinicon = true;
-defaults.show_statsinpopup = true;
-defaults.shouldShowBlockElementMenu = true;
-defaults.hidePlaceholders = true;
-
+let prefs = Object.create(null);
 let listeners = [];
 
-function defineProperty(key)
-{
-  let value = null;
-  Object.defineProperty(Prefs, key, {
-    get: function()
-    {
-      if (value === null)
-      {
-        if (key in ext.storage)
-        {
-          try
-          {
-            value = JSON.parse(ext.storage[key]);
-          }
-          catch(e)
-          {
-            Cu.reportError(e);
-          }
-        }
-
-        if (value === null)
-          value = JSON.parse(JSON.stringify(defaults[key]));
-      }
-      return value;
-    },
-    set: function(newValue)
-    {
-      if (typeof newValue != typeof defaults[key])
-        throw new Error("Attempt to change preference type");
-
-      let stringified = JSON.stringify(newValue);
-      if (stringified != JSON.stringify(defaults[key]))
-        ext.storage[key] = stringified;
-      else
-        delete ext.storage[key];
-
-      value = newValue;
-
-      for (let listener of listeners)
-        listener(key);
-
-      return value;
-    },
-    enumerable: true
-  });
-}
-
-
 let Prefs = exports.Prefs = {
   addListener: function(listener)
   {
@@ -102,8 +32,100 @@
     let index = listeners.indexOf(listener);
     if (index >= 0)
       listeners.splice(index, 1);
-  },
+  }
 };
 
-for (let key in defaults)
-  defineProperty(key);
+function keyToPref(key)
+{
+  if (key.indexOf(keyPrefix) != 0)
+    return null;
+
+  return key.substr(keyPrefix.length);
+}
+
+function prefToKey(pref)
+{
+  return keyPrefix + pref;
+}
+
+function addPreference(pref, defaultValue)
+{
+  prefs[pref] = undefined;
+
+  Object.defineProperty(Prefs, pref, {
+    get: function()
+    {
+      let value = prefs[pref];
+
+      if (typeof value != "undefined")
+        return value;
+
+      return defaultValue;
+    },
+    set: function(value)
+    {
+      if (typeof value != typeof defaultValue)
+        throw new Error("Attempt to change preference type");
+
+      if (value == defaultValue)
+      {
+        prefs[pref] = undefined;
+        ext.storage.remove(prefToKey(pref));
+      }
+      else
+      {
+        prefs[pref] = value;
+        ext.storage.set(prefToKey(pref), value);
+      }
+    },
+    enumerable: true
+  });
+}
+
+function setPreference(pref, value)
+{
+  prefs[pref] = value;
+
+  for (let listener of listeners)
+    listener(pref);
+}
+
+addPreference("enabled", true);
+addPreference("data_directory", "");
+addPreference("patternsbackups", 5);
+addPreference("patternsbackupinterval", 24);
+addPreference("savestats", false);
+addPreference("privateBrowsing", false);
+addPreference("subscriptions_fallbackerrors", 5);
+addPreference("subscriptions_fallbackurl", "https://adblockplus.org/getSubscription?version=%VERSION%&url=%SUBSCRIPTION%&downloadURL=%URL%&error=%ERROR%&channelStatus=%CHANNELSTATUS%&responseStatus=%RESPONSESTATUS%");
+addPreference("subscriptions_autoupdate", true);
+addPreference("subscriptions_exceptionsurl", "https://easylist-downloads.adblockplus.org/exceptionrules.txt");
+addPreference("subscriptions_antiadblockurl", "https://easylist-downloads.adblockplus.org/antiadblockfilters.txt");
+addPreference("documentation_link", "https://adblockplus.org/redirect?link=%LINK%&lang=%LANG%");
+addPreference("notificationdata", {});
+addPreference("notificationurl", "https://notification.adblockplus.org/notification.json");
+addPreference("stats_total", {});
+addPreference("show_statsinicon", true);
+addPreference("show_statsinpopup", true);
+addPreference("shouldShowBlockElementMenu", true);
+addPreference("hidePlaceholders", true);
+
+// Migrate preferences for users updating from old versions.
+// TODO: Remove the migration code after a few releases.
+ext.storage.migratePrefs(prefs);
+
+ext.storage.get(Object.keys(prefs).map(prefToKey), function(items)
+{
+  for (let key in items)
+    setPreference(keyToPref(key), items[key]);
+
+  ext.storage.onChanged.addListener(function(changes)
+  {
+    for (let key in changes)
+    {
+      let pref = keyToPref(key);
+      if (pref && pref in prefs)
+        setPreference(pref, changes[key].newValue);
+    }
+  });
+});