Issue 521 - Inject our stylesheet on per-site basis rather than globally

lib/elemHideFF.js

Index: lib/elemHideFF.js
===================================================================
rename from lib/elemHideStylesheet.js
rename to lib/elemHideFF.js
--- a/lib/elemHideStylesheet.js
+++ b/lib/elemHideFF.js
@@ -15,93 +15,36 @@
  * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 "use strict";
 
 let {port} = require("messaging");
 let {ElemHide} = require("elemHide");
 let {FilterNotifier} = require("filterNotifier");
+let {FilterStorage} = require("filterStorage");
 let {Prefs} = require("prefs");
-let {Utils} = require("utils");
+let {Policy} = require("contentPolicy");
 
-/**
- * Indicates whether the element hiding stylesheet is currently applied.
- * @type Boolean
- */
-let applied = false;
+FilterNotifier.on("elemhideupdate", () => port.emit("elemhideupdate"));
 
-/**
- * Stylesheet URL to be registered
- * @type nsIURI
- */
-let styleURL = Utils.makeURI("about:abp-elemhide?css");
+port.on("getSelectors", () => ElemHide.getSelectors());
 
-function init()
+port.on("elemhideEnabled", ({frames, isPrivate}) =>
 {
-  port.on("getSelectors", () => ElemHide.getSelectors());
+  if (!Prefs.enabled)
+    return {enabled: false};
 
-  apply();
-  onShutdown.add(unapply);
-
-  Prefs.addListener(function(name)
+  let hit = Policy.isFrameWhitelisted(frames, true);
+  if (hit)
   {
-    if (name == "enabled")
-      apply();
-  });
-
-  FilterNotifier.on("elemhideupdate", onUpdate);
-}
-
-function onUpdate()
-{
-  // Call apply() asynchronously and protect against reentrance - multiple
-  // change events shouldn't result in multiple calls.
-  if (onUpdate.inProgress)
-    return;
-
-  onUpdate.inProgress = true;
-  Utils.runAsync(() =>
-  {
-    onUpdate.inProgress = false;
-    apply();
-  });
-}
-
-function apply()
-{
-  unapply();
-
-  if (!Prefs.enabled)
-    return;
-
-  try
-  {
-    Utils.styleService.loadAndRegisterSheet(styleURL,
-        Ci.nsIStyleSheetService.USER_SHEET);
-    applied = true;
+    let [frameIndex, contentType, docDomain, thirdParty, location, filter] = hit;
+    if (!isPrivate)
+      FilterStorage.increaseHitCount(filter);
+    return {
+      enabled: false,
+      contentType, docDomain, thirdParty, location,
+      filter: filter.text, filterType: filter.type
+    };
   }
-  catch (e)
-  {
-    Cu.reportError(e);
-  }
-}
-
-function unapply()
-{
-  if (applied)
-  {
-    try
-    {
-      Utils.styleService.unregisterSheet(styleURL,
-          Ci.nsIStyleSheetService.USER_SHEET);
-    }
-    catch (e)
-    {
-      Cu.reportError(e);
-    }
-    applied = false;
-  }
-}
-
-// Send dummy message before initializing, this delay makes sure that the child
-// modules are loaded and our protocol handler registered.
-port.emitWithResponse("ping").then(init);
+  else
+    return {enabled: true};
+});