Updating variant overrides stores dirty values

app/assets/javascripts/admin/controllers/override_variants_controller.js.coffee

@@ -30,5 +30,8 @@ angular.module("ofn.admin").controller "AdminOverrideVariantsCtrl", ($scope, Ind
     $scope.hub = (hub for hub in hubs when hub.id == $scope.hub_id)[0]
 
 
+  $scope.displayDirty = ->
+
+
   $scope.update = ->
     StatusMessage.display 'success', 'Changes saved.'

app/assets/javascripts/admin/directives/track_variant_override.js.coffee

@@ -0,0 +1,9 @@
+angular.module("ofn.admin").directive "ofnTrackVariantOverride", (DirtyVariantOverrides) ->
+  require: "ngModel"
+  link: (scope, element, attrs, ngModel) ->
+    ngModel.$parsers.push (viewValue) ->
+      if ngModel.$dirty
+        variantOverride = scope.variantOverrides[scope.hub.id][scope.variant.id]
+        DirtyVariantOverrides.add variantOverride
+        scope.displayDirty()
+      viewValue

app/assets/javascripts/admin/services/dirty_variant_overrides.js.coffee

@@ -0,0 +1,7 @@
+angular.module("ofn.admin").factory "DirtyVariantOverrides", ->
+  new class DirtyVariantOverrides
+    dirtyVariantOverrides: {}
+
+    add: (vo) ->
+      @dirtyVariantOverrides[vo.hub_id] ||= {}
+      @dirtyVariantOverrides[vo.hub_id][vo.variant_id] = vo