Refactors most controllers and directives into classes for more organized and maintainable code

app/assets/javascripts/directives/functional/infiniteScroll.js

@@ -0,0 +1,17 @@
+/* @ngInject */
+export function infiniteScroll($rootScope, $window, $timeout) {
+  return {
+    link: function(scope, elem, attrs) {
+      const offset = parseInt(attrs.threshold) || 0;
+      const e = elem[0];
+      elem.on('scroll', function() {
+        if (
+          scope.$eval(attrs.canLoad) &&
+          e.scrollTop + e.offsetHeight >= e.scrollHeight - offset
+        ) {
+          scope.$apply(attrs.infiniteScroll);
+        }
+      });
+    }
+  };
+}