Visual Selector - Select smallest/most precise element first, better filtering of zero size elements

changedetectionio/res/xpath_element_scraper.js

@@ -1,3 +1,6 @@
+// Copyright (C) 2021 Leigh Morresi (dgtlmoon@gmail.com)
+// All rights reserved.
+
 // @file Scrape the page looking for elements of concern (%ELEMENTS%)
 // http://matatk.agrip.org.uk/tests/position-and-width/
 // https://stackoverflow.com/questions/26813480/when-is-element-getboundingclientrect-guaranteed-to-be-updated-accurate
@@ -89,8 +92,8 @@ for (var i = 0; i < elements.length; i++) {
         continue
     }
 
-    // Forget really small ones
+    // Skip really small ones, and where width or height ==0
-    if (bbox['width'] < 10 && bbox['height'] < 10) {
+    if (bbox['width'] * bbox['height'] < 100) {
         continue;
     }
 
@@ -146,7 +149,6 @@ for (var i = 0; i < elements.length; i++) {
 
 }
 
-
 // Inject the current one set in the include_filters, which may be a CSS rule
 // used for displaying the current one in VisualSelector, where its not one we generated.
 if (include_filters.length) {
@@ -205,5 +207,9 @@ if (include_filters.length) {
     }
 }
 
+// Sort the elements so we find the smallest one first, in other words, we find the smallest one matching in that area
+// so that we dont select the wrapping element by mistake and be unable to select what we want
+size_pos.sort((a, b) => (a.width*a.height > b.width*b.height) ? 1 : -1)
+
 // Window.width required for proper scaling in the frontend
 return {'size_pos': size_pos, 'browser_width': window.innerWidth};

changedetectionio/static/js/visual-selector.js

@@ -1,4 +1,5 @@
-// Horrible proof of concept code :)
+// Copyright (C) 2021 Leigh Morresi (dgtlmoon@gmail.com)
+// All rights reserved.
 // yes - this is really a hack, if you are a front-ender and want to help, please get in touch!
 
 $(document).ready(function () {
@@ -177,9 +178,10 @@ $(document).ready(function () {
             // Basically, find the most 'deepest'
             var found = 0;
             ctx.fillStyle = 'rgba(205,0,0,0.35)';
-            for (var i = selector_data['size_pos'].length; i !== 0; i--) {
+            // Will be sorted by smallest width*height first
+            for (var i = 0; i <= selector_data['size_pos'].length; i++) {
                 // draw all of them? let them choose somehow?
-                var sel = selector_data['size_pos'][i - 1];
+                var sel = selector_data['size_pos'][i];
                 // If we are in a bounding-box
                 if (e.offsetY > sel.top * y_scale && e.offsetY < sel.top * y_scale + sel.height * y_scale
                     &&
@@ -195,7 +197,7 @@ $(document).ready(function () {
                     // no need to keep digging
                     // @todo or, O to go out/up, I to go in
                     // or double click to go up/out the selector?
-                    current_selected_i = i - 1;
+                    current_selected_i = i;
                     found += 1;
                     break;
                 }