Issue 1282 - Don't generate filters conflicting with existing exception rules

include.postload.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2015 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/>.
  */
 
 // Click-to-hide stuff
 var clickHide_activated = false;
 var clickHide_filters = null;
 var currentElement = null;
 var highlightedElementsSelector = null;
 var clickHideFiltersDialog = null;
 var lastRightClickEvent = null;
 var lastRightClickEventValid = false;
+var lastMouseOverEvent = null;
 
 function highlightElement(element, shadowColor, backgroundColor)
 {
   unhighlightElement(element);
 
   var highlightWithOverlay = function()
   {
     var overlay = addElementOverlay(element);
+
+    // If the element isn't displayed no overlay will be added.
+    // Moreover, we don't need to highlight anything then.
+    if (!overlay)
+      return;
 
     highlightElement(overlay, shadowColor, backgroundColor);
     overlay.style.pointerEvents = "none";
 
     element._unhighlight = function()
     {
       overlay.parentNode.removeChild(overlay);
     };
   };
 
@@ skipping 142 matching lines @@
 
     case "video":
     case "audio":
     case "picture":
       return getURLsFromMediaElement(element);
   }
 
   return getURLsFromAttributes(element);
 }
 
-// Gets the absolute position of an element by walking up the DOM tree,
-// adding up offsets.
-// I hope there's a better way because it just seems absolutely stupid
-// that the DOM wouldn't have a direct way to get this, given that it
-// has hundreds and hundreds of other methods that do random junk.
-function getAbsolutePosition(elt) {
-  var l = 0;
-  var t = 0;
-  for(; elt; elt = elt.offsetParent) {
-    l += elt.offsetLeft;
-    t += elt.offsetTop;
-  }
-  return [l, t];
-}
-
 // Adds an overlay to an element, which is probably a Flash object
 function addElementOverlay(elt) {
   var zIndex = "auto";
   var position = "absolute";
 
   for (var e = elt; e; e = e.parentElement)
   {
     var style = getComputedStyle(e);
 
     // If the element isn't rendered (since its or one of its ancestor's
     // "display" property is "none"), the overlay wouldn't match the element.
     if (style.display == "none")
       return null;
 
     // If the element or one of its ancestors uses fixed postioning, the overlay
     // has to use fixed postioning too. Otherwise it might not match the element.
     if (style.position == "fixed")
       position = "fixed";
 
     // Determine the effective z-index, which is the highest z-index used
-    // by the element and its offset ancestors. When using a lower z-index
-    // the element would cover the overlay. When using a higher z-index the
-    // overlay might also cover other elements.
+    // by the element and its offset ancestors, and increase it by one.
+    // When using a lower z-index the element would cover the overlay.
+    // When using a higher z-index the overlay might also cover other elements.
     if (style.position != "static" && style.zIndex != "auto")
     {
-      if (zIndex == "auto")
-        zIndex = style.zIndex;
-      else
-        zIndex = Math.max(zIndex, style.zIndex);
+      var curZIndex = parseInt(style.zIndex, 10) + 1;
+
+      if (zIndex == "auto" || curZIndex > zIndex)
+        zIndex = curZIndex;
     }
   }
 
   var overlay = document.createElement('div');
   overlay.prisoner = elt;
   overlay.className = "__adblockplus__overlay";
   overlay.setAttribute('style', 'opacity:0.4; display:inline-box; overflow:hidden; box-sizing:border-box;');
-  var pos = getAbsolutePosition(elt);
-  overlay.style.width = elt.offsetWidth + "px";
-  overlay.style.height = elt.offsetHeight + "px";
-  overlay.style.left = pos[0] + "px";
-  overlay.style.top = pos[1] + "px";
+  var rect = elt.getBoundingClientRect();
+  overlay.style.width = rect.width + "px";
+  overlay.style.height = rect.height + "px";
+  overlay.style.left = (rect.left + window.scrollX) + "px";
+  overlay.style.top = (rect.top + window.scrollY) + "px";
   overlay.style.position = position;
   overlay.style.zIndex = zIndex;
 
   // elt.parentNode.appendChild(overlay, elt);
-  document.body.appendChild(overlay);
+  document.documentElement.appendChild(overlay);
   return overlay;
 }
 
 // Show dialog asking user whether she wants to add the proposed filters derived
 // from selected page element
 function clickHide_showDialog(left, top, filters)
 {
   // If we are already selecting, abort now
   if (clickHide_activated || clickHideFiltersDialog)
     clickHide_deactivate(true);
@@ skipping 16 matching lines @@
   {
     if (clickHideFiltersDialog)
       clickHideFiltersDialog.style.setProperty("opacity", "0.7");
   };
   clickHideFiltersDialog.onmouseover = function()
   {
     if (clickHideFiltersDialog)
       clickHideFiltersDialog.style.setProperty("opacity", "1.0");
   };
 
-  document.body.appendChild(clickHideFiltersDialog);
+  document.documentElement.appendChild(clickHideFiltersDialog);
 }
 
 // Turn on the choose element to create filter thing
 function clickHide_activate() {
   if(document == null)
     return;
 
   // If we are already selecting, abort now
   if (clickHide_activated || clickHideFiltersDialog)
     clickHide_deactivate();
 
-  // Add overlays for blockable elements that don't emit mouse events that they can still be selected
+  // Add overlays for blockable elements that don't emit mouse events,
+  // so that they can still be selected.
   [].forEach.call(
-    document.querySelectorAll('object,embed,iframe'),
+    document.querySelectorAll('object,embed,iframe,frame'),
     function(element)
     {
       getFiltersForElement(element, function(filters)
       {
         if (filters.length > 0)
           addElementOverlay(element);
       });
     }
   );
 
   clickHide_activated = true;
+  document.addEventListener("mousedown", clickHide_stopPropagation, true);
+  document.addEventListener("mouseup", clickHide_stopPropagation, true);
+  document.addEventListener("mouseenter", clickHide_stopPropagation, true);
+  document.addEventListener("mouseleave", clickHide_stopPropagation, true);
   document.addEventListener("mouseover", clickHide_mouseOver, true);
   document.addEventListener("mouseout", clickHide_mouseOut, true);
   document.addEventListener("click", clickHide_mouseClick, true);
   document.addEventListener("keydown", clickHide_keyDown, true);
+
+  ext.onExtensionUnloaded.addListener(clickHide_deactivate);
 }
 
 // Called when user has clicked on something and we are waiting for confirmation
 // on whether the user actually wants these filters
 function clickHide_rulesPending() {
   clickHide_activated = false;
+  document.removeEventListener("mousedown", clickHide_stopPropagation, true);
+  document.removeEventListener("mouseup", clickHide_stopPropagation, true);
+  document.removeEventListener("mouseenter", clickHide_stopPropagation, true);
+  document.removeEventListener("mouseleave", clickHide_stopPropagation, true);
   document.removeEventListener("mouseover", clickHide_mouseOver, true);
   document.removeEventListener("mouseout", clickHide_mouseOut, true);
   document.removeEventListener("click", clickHide_mouseClick, true);
   document.removeEventListener("keydown", clickHide_keyDown, true);
 }
 
 // Turn off click-to-hide
 function clickHide_deactivate(keepOverlays)
 {
   if (clickHideFiltersDialog)
   {
-    document.body.removeChild(clickHideFiltersDialog);
+    document.documentElement.removeChild(clickHideFiltersDialog);
     clickHideFiltersDialog = null;
   }
 
   clickHide_activated = false;
   clickHide_filters = null;
   if(!document)
     return; // This can happen inside a nuked iframe...I think
+
+  document.removeEventListener("mousedown", clickHide_stopPropagation, true);
+  document.removeEventListener("mouseup", clickHide_stopPropagation, true);
+  document.removeEventListener("mouseenter", clickHide_stopPropagation, true);
+  document.removeEventListener("mouseleave", clickHide_stopPropagation, true);
   document.removeEventListener("mouseover", clickHide_mouseOver, true);
   document.removeEventListener("mouseout", clickHide_mouseOut, true);
   document.removeEventListener("click", clickHide_mouseClick, true);
   document.removeEventListener("keydown", clickHide_keyDown, true);
 
-  if (!keepOverlays)
+  if (keepOverlays !== true)
   {
     lastRightClickEvent = null;
 
     if (currentElement) {
       currentElement.removeEventListener("contextmenu",  clickHide_elementClickHandler, true);
       unhighlightElements();
       unhighlightElement(currentElement);
       currentElement = null;
     }
     unhighlightElements();
 
     var overlays = document.getElementsByClassName("__adblockplus__overlay");
     while (overlays.length > 0)
       overlays[0].parentNode.removeChild(overlays[0]);
-  }
-}
-
-function clickHide_elementClickHandler(ev) {
-  ev.preventDefault();
-  ev.stopPropagation();
-  clickHide_mouseClick(ev);
+
+    ext.onExtensionUnloaded.removeListener(clickHide_deactivate);
+  }
+}
+
+function clickHide_stopPropagation(e)
+{
+  e.stopPropagation();
+}
+
+function clickHide_elementClickHandler(e) {
+  e.preventDefault();
+  e.stopPropagation();
+  clickHide_mouseClick(e);
 }
 
 function getBlockableElementOrAncestor(element, callback)
 {
-  if (element && element != document.documentElement &&
-                 element != document.body)
-  {
-    if (element instanceof HTMLElement)
+  // We assume that the user doesn't want to block the whole page.
+  // So we never consider the <html> or <body> element.
+  while (element && element != document.documentElement
+                 && element != document.body)
+  {
+    // We can't handle non-HTML (like SVG) elements, as well as
+    // <area> elements (see below). So fall back to the parent element.
+    if (!(element instanceof HTMLElement) || element.localName == "area")
+      element = element.parentElement;
+
+    // If image maps are used mouse events occur for the <area> element.
+    // But we have to block the image associated with the <map> element.
+    else if (element.localName == "map")
+    {
+      var images = document.querySelectorAll("img[usemap]");
+      var image = null;
+
+      for (var i = 0; i < images.length; i++)
+      {
+        var usemap = image.getAttribute("usemap");
+        var index = usemap.indexOf("#");
+
+        if (index != -1 && usemap.substr(index + 1) == element.name)
+        {
+          image = images[i];
+          break;
+        }
+      }
+
+      element = image;
+    }
+
+    // Finally, if none of the above is true, check whether we can generate
+    // any filters for this element. Otherwise fall back to its parent element.
+    else
     {
       getFiltersForElement(element, function(filters)
       {
         if (filters.length > 0)
           callback(element);
         else
           getBlockableElementOrAncestor(element.parentElement, callback);
       });
-    }
-    else
-    {
-      getBlockableElementOrAncestor(element.parentElement, callback);
-    }
-  }
-  else
-  {
-    callback(null);
-  }
+
+      return;
+    }
+  }
+
+  // We reached the document root without finding a blockable element.
+  callback(null);
 }
 
 // Hovering over an element so highlight it
 function clickHide_mouseOver(e)
 {
-  if (clickHide_activated == false)
-    return;
+  lastMouseOverEvent = e;
 
   getBlockableElementOrAncestor(e.target, function(element)
   {
-    if (currentElement)
-      unhighlightElement(currentElement);
-
-    if (element)
-    {
-      highlightElement(element, "#d6d84b", "#f8fa47");
-      element.addEventListener("contextmenu", clickHide_elementClickHandler, true);
-    }
-
-    currentElement = element;
+    if (e == lastMouseOverEvent)
+    {
+      lastMouseOverEvent = null;
+
+      if (clickHide_activated)
+      {
+        if (currentElement)
+          unhighlightElement(currentElement);
+
+        if (element)
+        {
+          highlightElement(element, "#d6d84b", "#f8fa47");
+          element.addEventListener("contextmenu", clickHide_elementClickHandler, true);
+        }
+
+        currentElement = element;
+      }
+    }
   });
+
+  e.stopPropagation();
 }
 
 // No longer hovering over this element so unhighlight it
 function clickHide_mouseOut(e)
 {
   if (!clickHide_activated || currentElement != e.target)
     return;
 
   unhighlightElement(currentElement);
   currentElement.removeEventListener("contextmenu", clickHide_elementClickHandler, true);
+  e.stopPropagation();
 }
 
 // Selects the currently hovered-over filter or cancels selection
 function clickHide_keyDown(e)
 {
   if (!e.ctrlKey && !e.altKey && !e.shiftKey && e.keyCode == 13 /*DOM_VK_RETURN*/)
      clickHide_mouseClick(e);
   else if (!e.ctrlKey && !e.altKey && !e.shiftKey && e.keyCode == 27 /*DOM_VK_ESCAPE*/)
   {
     ext.backgroundPage.sendMessage(
@@ skipping 192 matching lines @@
         break;
       case "clickhide-activate":
         clickHide_activate();
         break;
       case "clickhide-deactivate":
         clickHide_deactivate();
         break;
       case "clickhide-new-filter":
         if(lastRightClickEvent)
         {
-          clickHide_activated = true;
-          currentElement = lastRightClickEvent.target;
-          clickHide_mouseClick(lastRightClickEvent);
+          getBlockableElementOrAncestor(lastRightClickEvent.target, function(element)
+          {
+            clickHide_activated = true;
+            currentElement = element;
+            clickHide_mouseClick(lastRightClickEvent);
+          });
         }
         break;
       case "clickhide-init":
         if (clickHideFiltersDialog)
         {
           sendResponse({filters: clickHide_filters});
 
           clickHideFiltersDialog.style.width = msg.width + "px";
           clickHideFiltersDialog.style.height = msg.height + "px";
           clickHideFiltersDialog.style.visibility = "visible";
@@ skipping 27 matching lines @@
           lastRightClickEventValid = false;
         else
           lastRightClickEvent = null;
         break;
     }
   });
 
   if (window == window.top)
     ext.backgroundPage.sendMessage({type: "report-html-page"});
 }