On save, scale from chosen unit to base unit (eg. mL to L)

app/assets/javascripts/admin/bulk_product_update.js.coffee

@@ -299,14 +299,16 @@ productsApp.controller "AdminBulkProductsCtrl", [
           product.variant_unit_scale = null
       if product.variants
         for id, variant of product.variants
-          $scope.packVariant variant
+          $scope.packVariant product, variant
 
 
-    $scope.packVariant = (variant) ->
+    $scope.packVariant = (product, variant) ->
       if variant.hasOwnProperty("unit_value_with_description")
         match = variant.unit_value_with_description.match(/^([\d\.]+|)( |)(.*)$/)
         if match
-          variant.unit_value = parseFloat(match[1]) || null
+          product = $scope.findProduct(product.id)
+          variant.unit_value  = parseFloat(match[1]) || null
+          variant.unit_value *= product.variant_unit_scale if variant.unit_value
           variant.unit_description = match[3]
 
 
@@ -323,6 +325,12 @@ productsApp.controller "AdminBulkProductsCtrl", [
               delete variant.options_text
       products_filtered
 
+
+    $scope.findProduct = (id) ->
+      products = (product for product in $scope.products when product.id == id)
+      if products.length == 0 then null else products[0]
+
+
     $scope.setMessage = (model, text, style, timeout) ->
       model.text = text
       model.style = style

spec/javascripts/unit/bulk_product_update_spec.js.coffee

@@ -539,20 +539,28 @@ describe "AdminBulkProductsCtrl", ->
 
         scope.packProduct(testProduct)
 
-        expect(scope.packVariant).toHaveBeenCalledWith(testVariant)
+        expect(scope.packVariant).toHaveBeenCalledWith(testProduct, testVariant)
 
     describe "packing variants", ->
+      testProduct = {id: 123}
+
+      beforeEach ->
+        scope.products = [testProduct]
+
       it "extracts unit_value and unit_description from unit_value_with_description", ->
+        testProduct = {id: 123, variant_unit_scale: 1.0}
         testVariant = {unit_value_with_description: "250.5 (bottle)"}
-        scope.packVariant(testVariant)
+        scope.products = [testProduct]
+        scope.packVariant(testProduct, testVariant)
         expect(testVariant).toEqual
           unit_value: 250.5
           unit_description: "(bottle)"
           unit_value_with_description: "250.5 (bottle)"
 
       it "extracts into unit_value when only a number is provided", ->
+        testProduct = {id: 123, variant_unit_scale: 1.0}
         testVariant = {unit_value_with_description: "250.5"}
-        scope.packVariant(testVariant)
+        scope.packVariant(testProduct, testVariant)
         expect(testVariant).toEqual
           unit_value: 250.5
           unit_description: ''
@@ -560,7 +568,7 @@ describe "AdminBulkProductsCtrl", ->
 
       it "extracts into unit_description when only a string is provided", ->
         testVariant = {unit_value_with_description: "Medium"}
-        scope.packVariant(testVariant)
+        scope.packVariant(testProduct, testVariant)
         expect(testVariant).toEqual
           unit_value: null
           unit_description: 'Medium'
@@ -568,7 +576,7 @@ describe "AdminBulkProductsCtrl", ->
 
       it "sets blank values when no value provided", ->
         testVariant = {unit_value_with_description: ""}
-        scope.packVariant(testVariant)
+        scope.packVariant(testProduct, testVariant)
         expect(testVariant).toEqual
           unit_value: null
           unit_description: ''
@@ -576,9 +584,19 @@ describe "AdminBulkProductsCtrl", ->
 
       it "sets nothing when the field is undefined", ->
         testVariant = {}
-        scope.packVariant(testVariant)
+        scope.packVariant(testProduct, testVariant)
         expect(testVariant).toEqual {}
 
+      it "converts value from chosen unit to base unit", ->
+        testProduct = {id: 123, variant_unit_scale: 1000}
+        testVariant = {unit_value_with_description: "250.5"}
+        scope.products = [testProduct]
+        scope.packVariant(testProduct, testVariant)
+        expect(testVariant).toEqual
+          unit_value: 250500
+          unit_description: ''
+          unit_value_with_description: "250.5"
+
 
     describe "filtering products", ->
       beforeEach ->
@@ -704,6 +722,17 @@ describe "AdminBulkProductsCtrl", ->
         ]
 
 
+  describe "fetching a product by id", ->
+    it "returns the product when it is present", ->
+      product = {id: 123}
+      scope.products = [product]
+      expect(scope.findProduct(123)).toEqual product
+
+    it "returns null when the product is not present", ->
+      scope.products = []
+      expect(scope.findProduct(123)).toBeNull()
+
+
   describe "deleting products", ->
     it "deletes products with a http delete request to /api/products/id", ->
       spyOn(window, "confirm").andReturn true