Added ad counting functionality

lib/stats.js

Index: lib/stats.js
===================================================================
new file mode 100644
--- /dev/null
+++ b/lib/stats.js
@@ -0,0 +1,67 @@
+/*
+ * This file is part of Adblock Plus <http://adblockplus.org/>,
+ * Copyright (C) 2006-2013 Eyeo GmbH
+ *
+ * Adblock Plus is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * Adblock Plus is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/**
+ * @fileOverview Provides usage stats
+ */
+
+let {Prefs} = require("prefs");
+let {BlockingFilter} = require("filterClasses");
+let {FilterNotifier} = require("filterNotifier");
+
+/**
+ * Get statistics for specified tab
+ * @param  {String} key   field key
+ * @param  {Number} tabId tab ID (leave undefined for total stats)
+ * @return {Number}       field value
+ */
+let getStats = exports.getStats = function getStats(key, tabId)
+{
+  if (tabId)
+  {
+    let frameData = getFrameData(tabId, 0);
+    return (frameData && key in frameData ? frameData[key] : 0);
+  }
+  else
+    return (key in Prefs.stats_total ? Prefs.stats_total[key] : 0);
+};
+
+FilterNotifier.addListener(function(action, item, newValue, oldValue, tabId)
+{
+  if (action != "filter.hitCount")
+    return;
+  
+  var blocked = item instanceof BlockingFilter;
+  
+  // Increment counts
+  if (blocked)
+  {
+    if ("blocked" in Prefs.stats_total)
+      Prefs.stats_total.blocked++;
+    else
+      Prefs.stats_total.blocked = 1;
+    
+    let frameData = getFrameData(tabId, 0);
+    if (frameData)
+    {
+      if ("blocked" in frameData)
+        frameData.blocked++;
+      else
+        frameData.blocked = 1;
+    }
+  }
+});