confirm changes to default card

app/assets/javascripts/darkswarm/controllers/credit_cards_controller.js.coffee

@@ -1,7 +1,7 @@
 Darkswarm.controller "CreditCardsCtrl", ($scope, CreditCard, CreditCards) ->
   angular.extend(this, new FieldsetMixin($scope))
   $scope.savedCreditCards = CreditCards.saved
-  $scope.setDefault = CreditCards.setDefault
+  $scope.confirmSetDefault = CreditCards.confirmSetDefault
   $scope.CreditCard = CreditCard
   $scope.secrets = CreditCard.secrets
   $scope.showForm = CreditCard.show

app/assets/javascripts/darkswarm/services/credit_cards.js.coffee

@@ -5,11 +5,15 @@ Darkswarm.factory 'CreditCards', ($http, $filter, savedCreditCards, Messages)->
     add: (card) ->
       @saved.push card
 
-    setDefault: (card) =>
-      card.is_default = true
-      for othercard in @saved when othercard != card
-        othercard.is_default = false
-      $http.put("/credit_cards/#{card.id}", is_default: true).then (data) ->
-        Messages.success(t('js.default_card_updated'))
-      , (response) ->
-        Messages.flash(response.data.flash)
+    confirmSetDefault: (card, event) =>
+      if confirm t("js.default_card_voids_auth")
+        card.is_default = true
+        for othercard in @saved when othercard != card
+          othercard.is_default = false
+        $http.put("/credit_cards/#{card.id}", is_default: true).then (data) ->
+          Messages.success(t('js.default_card_updated'))
+        , (response) ->
+          Messages.flash(response.data.flash)
+      else
+        event.preventDefault()
+        return false

app/views/spree/users/_saved_cards.html.haml

@@ -10,7 +10,7 @@
     %td.number{ ng: { bind: '::card.number' } }
     %td.expiry{ ng: { bind: '::card.expiry' } }
     %td.is-default
-      %input{ type: 'radio', name: 'default_card', ng: { model: 'card.is_default', change: 'setDefault(card)', value: "true"} }
+      %input{ type: 'radio', name: 'default_card', ng: { model: 'card.is_default', click: 'confirmSetDefault(card, $event)', value: "true"} }
     %td.actions
       %a{"rel" => "nofollow", "data-method" => "delete", "ng-href" => "{{card.delete_link}}" }
         = t(:delete)

config/locales/en.yml

@@ -2525,6 +2525,7 @@ See the %{link} to find out more about %{sitename}'s features and to start using
     resolve_errors: Please resolve the following errors
     more_items: "+ %{count} More"
     default_card_updated: Default Card Updated
+    default_card_voids_auth: Changing your default card will remove shops' existing authorizations to charge it. You can re-authorize shops after updating the default card. Do you wish to change the default card?"
     cart:
       add_to_cart_failed: >
         There was a problem adding this product to the cart.