1237 - Show total item value for each location (#1279)

* add methods to return the invetory total value

* change the view to show the inventory total value

app/models/storage_location.rb

@@ -60,6 +60,14 @@ def size
     inventory_items.sum(:quantity)
   end
 
+  def inventory_total_value_in_dollars
+    inventory_total_value = inventory_items.joins(:item).map do |inventory_item|
+      value_in_cents = inventory_item.item.try(:value_in_cents)
+      value_in_cents * inventory_item.quantity
+    end.reduce(:+)
+    inventory_total_value.present? ? (inventory_total_value / 100) : 0
+  end
+
   def to_csv
     org = organization
 

app/views/storage_locations/_storage_location_row.html.erb

@@ -2,6 +2,7 @@
   <td><%= storage_location.name %></td>
   <td><%= storage_location.address %></td>
   <td class="numeric"><%= storage_location.size %></td>
+  <td><%= number_to_currency(storage_location.inventory_total_value_in_dollars) %></td>
   <td class="text-right">
     <%= view_button_to storage_location %>
     <%= edit_button_to edit_storage_location_path(storage_location) %>

app/views/storage_locations/index.html.erb

@@ -49,6 +49,7 @@
                   <th>Name</th>
                   <th>Address</th>
                   <th class="numeric">Total Inventory</th>
+                  <th>Inventory Value</th>
                   <th class="pull-right">Actions</th>
                 </tr>
               </thead>

spec/models/storage_location_spec.rb

@@ -145,6 +145,22 @@
       end
     end
 
+    describe "inventory_total_value_in_dollars" do
+      it "returns total value of all items in this storage location" do
+        storage_location = create(:storage_location)
+        item1 = create(:item, value_in_cents: 100)
+        item2 = create(:item, value_in_cents: 200)
+        create(:inventory_item, storage_location_id: storage_location.id, item_id: item1.id, quantity: 10)
+        create(:inventory_item, storage_location_id: storage_location.id, item_id: item2.id, quantity: 10)
+        expect(storage_location.inventory_total_value_in_dollars).to eq(30)
+      end
+
+      it "returns 0 when there are no items in this storage location" do
+        storage_location = create(:storage_location)
+        expect(storage_location.inventory_total_value_in_dollars).to eq(0)
+      end
+    end
+
     describe "import_csv" do
       it "imports storage locations from a csv file" do
         before_import = StorageLocation.count