WIP: Have one global element hide stylesheet and inject the other ones per site

lib/elemHide.js

Index: lib/elemHide.js
===================================================================
--- a/lib/elemHide.js
+++ b/lib/elemHide.js
@@ -61,16 +61,19 @@ let exceptions = Object.create(null);
 let styleURL = null;
 
 /**
  * Global stylesheet that should be loaded into content windows.
  * @type nsIStyleSheet
  */
 let styleSheet = null;
 
+// fixme
+let filterByDomain = Object.create(null);
+
 /**
  * Use new way of injecting styles per Window that exists since Firefox 33.
  * @type boolean
  */
 let useNew = ('preloadSheet' in Utils.styleService);
 
 /**
  * Element hiding component
@@ -136,16 +139,53 @@ let ElemHide = exports.ElemHide =
       return;
 
     if (!Prefs.enabled)
       return;
 
     if (Policy.shouldNeverBlockWindow(subject))
       return;
 
+    dump(subject.document.documentURIObject.spec + "\n");
+    let domain = subject.document.documentURIObject.host;
+    if (domain.startsWith("www."))
+      domain = domain.substring(4);
+
+    dump("domain: " + domain + "\n"); // xxx is elemhide port or subdomain insesitive?
+
+    let list = Object.create(null);
+    for (let filter of filterByDomain[domain])
+    {
+      dump("filter: " + filter.text + "\n")
+      dump("key:  " +  keyByFilter[filter.text] + "\n")
+      list[keyByFilter[filter.text]] = filter;
+    }
+
+    if (filterByDomain[domain]) {
+      // XXX seems to stupid to use a file for this.
+      // Somehow get this to use a data url or similar
+      let styleFile = IO.resolveFilePath(Prefs.data_directory);
+      styleFile.append(domain + ".css");
+      styleURL = Services.io.newFileURI(styleFile).QueryInterface(Ci.nsIFileURL);
+
+      IO.writeToFile(styleURL.file, this._generateCSSContent(list, false), function(e)
+      {
+        try
+        {
+          let utils = subject.QueryInterface(Ci.nsIInterfaceRequestor)
+                             .getInterface(Ci.nsIDOMWindowUtils);
+          utils.loadSheet(styleURL, Ci.nsIStyleSheetService.USER_SHEET);
+        }
+        catch (e)
+        {
+          Cu.reportError(e);
+        }
+      });
+    }
+
     try
     {
       let utils = subject.QueryInterface(Ci.nsIInterfaceRequestor)
                          .getInterface(Ci.nsIDOMWindowUtils);
       utils.addSheet(styleSheet, Ci.nsIStyleSheetService.USER_SHEET);
     }
     catch (e)
     {
@@ -157,16 +197,17 @@ let ElemHide = exports.ElemHide =
    * Removes all known filters
    */
   clear: function()
   {
     filterByKey = Object.create(null);
     keyByFilter = Object.create(null);
     knownExceptions = Object.create(null);
     exceptions = Object.create(null);
+    filterByDomain = Object.create(null);
     ElemHide.isDirty = false;
     ElemHide.unapply();
   },
 
   /**
    * Add a new element hiding filter
    * @param {ElemHideFilter} filter
    */
@@ -183,16 +224,30 @@ let ElemHide = exports.ElemHide =
       exceptions[selector].push(filter);
       knownExceptions[filter.text] = true;
     }
     else
     {
       if (filter.text in keyByFilter)
         return;
 
+      if (filter.selectorDomain && useNew)
+      {
+        let domains = filter.selectorDomain.split(",");
+
+        for (let domain of domains)
+        {
+          dump(domain + "\n");
+          if (filterByDomain[domain])
+            filterByDomain[domain].push(filter);
+          else
+            filterByDomain[domain] = [filter];
+        }
+      }
+
       let key;
       do {
         key = Math.random().toFixed(15).substr(5);
       } while (key in filterByKey);
 
       filterByKey[key] = filter;
       keyByFilter[filter.text] = key;
       ElemHide.isDirty = true;
@@ -216,24 +271,33 @@ let ElemHide = exports.ElemHide =
         list.splice(index, 1);
       delete knownExceptions[filter.text];
     }
     else
     {
       if (!(filter.text in keyByFilter))
         return;
 
+      // if (filter.selectorDomain && useNew)
+      // {
+      //   let filters = filterByDomain[filter.selectorDomain];
+      //   if (Array.isArray(filters))
+      //     filters.splice(filters.indexOf(filter), 1);
+      //   else
+      //     delete filterByDomain[filter.selectorDomain];
+      // }
+
       let key = keyByFilter[filter.text];
       delete filterByKey[key];
       delete keyByFilter[filter.text];
       ElemHide.isDirty = true;
     }
   },
 
-  /**
+  /** 
    * Checks whether an exception rule is registered for a filter on a particular
    * domain.
    */
   getException: function(/**Filter*/ filter, /**String*/ docDomain) /**ElemHideException*/
   {
     let selector = filter.selector;
     if (!(filter.selector in exceptions))
       return null;
@@ -294,17 +358,17 @@ let ElemHide = exports.ElemHide =
         ElemHide.unapply();
         TimeLine.log("ElemHide.unapply() finished");
       }
 
       TimeLine.leave("ElemHide.apply() done (no file changes)");
       return;
     }
 
-    IO.writeToFile(styleURL.file, this._generateCSSContent(), function(e)
+    IO.writeToFile(styleURL.file, this._generateCSSContent(filterByKey, useNew), function(e)
     {
       TimeLine.enter("ElemHide.apply() write callback");
       this._applying = false;
 
       // _generateCSSContent is throwing NS_ERROR_NOT_AVAILABLE to indicate that
       // there are no filters. If that exception is passed through XPCOM we will
       // see a proper exception here, otherwise a number.
       let noFilters = (e == Cr.NS_ERROR_NOT_AVAILABLE || (e && e.result == Cr.NS_ERROR_NOT_AVAILABLE));
@@ -351,27 +415,30 @@ let ElemHide = exports.ElemHide =
       TimeLine.leave("ElemHide.apply() write callback done");
     }.bind(this), "ElemHideWrite");
 
     this._applying = true;
 
     TimeLine.leave("ElemHide.apply() done", "ElemHideWrite");
   },
 
-  _generateCSSContent: function()
+  _generateCSSContent: function(filters, onlyGlobal)
   {
     // Grouping selectors by domains
     TimeLine.log("start grouping selectors");
     let domains = Object.create(null);
     let hasFilters = false;
-    for (let key in filterByKey)
+    for (let key in filters)
     {
-      let filter = filterByKey[key];
+      let filter = filters[key];
       let domain = filter.selectorDomain || "";
 
+      if (onlyGlobal && domain)
+        continue;
+
       let list;
       if (domain in domains)
         list = domains[domain];
       else
       {
         list = Object.create(null);
         domains[domain] = list;
       }