refactor(DeCoffee): convert label-origin directive to es6

app/index.jade

@@ -148,7 +148,7 @@ head
   script(src='build/js/directives/is-valid.directive.js')
   script(src='build/js/directives/is-not-equal.directive.js')
   script(src='build/js/directives/transform-currency.js')
-  script(src='build/js/directives/label-origin.js')
+  script(src='build/js/directives/label-origin.directive.js')
   script(src='build/js/directives/destinationInput.directive.js')
   script(src='build/js/directives/scroll-in-view.js')
   script(src='build/js/directives/public-header.directive.js')

assets/js/directives/label-origin.directive.js

@@ -0,0 +1,38 @@
+angular
+  .module('walletApp')
+  .directive('labelOrigin', labelOrigin);
+
+function labelOrigin(Wallet, currency) {
+  const directive = {
+    restrict: 'E',
+    replace: true,
+    templateUrl: 'templates/label-origin.jade',
+    scope: {
+      origin: '=',
+      fee: '=',
+      highlight: '='
+    },
+    link: link
+  };
+  return directive;
+
+  function link(scope, elem, attrs) {
+    scope.settings = Wallet.settings;
+    scope.isBitCurrency = currency.isBitCurrency;
+
+    scope.determineAvailableBalance = (balance) => {
+      if (balance == null) return;
+
+      finalBalance = parseInt(balance);
+      if (scope.fee) finalBalance -= parseInt(scope.fee);
+
+      return finalBalance < 0 ? 0 : finalBalance;
+    };
+
+    scope.determineLabel = (origin) => {
+      if (origin == null) return;
+      return origin.label || origin.address;
+    };
+
+  }
+}