Adding method to find template width and height w/ test. Part of #37.

app/models/template.rb

@@ -39,4 +39,17 @@ def import_xml(xml)
     end
     return self.valid?
   end
+
+
+  # Update the original_width and original_height
+  # fields using the orignal image.
+  def update_original_sizes
+    original_media = self.media.original.first
+    unless original_media.nil?
+      image = Magick::Image.from_blob(original_media.file_contents).first
+      self.original_width = image.columns
+      self.original_height = image.rows
+    end
+    return true
+  end
 end

test/unit/template_test.rb

@@ -16,4 +16,16 @@ class TemplateTest < ActiveSupport::TestCase
     file = fixture_file_upload("/files/no_fields_template.xml", 'text/xml')
     assert t.import_xml(file.read)
   end
+
+  # Do we correctly find the original height and orignal width?
+  test "find original height and width" do
+    t = Template.new
+    file = fixture_file_upload("/files/concerto_background.jpg", 'image/jpeg')
+    t.save
+    media = t.media.build(:file => file, :key => 'original')
+    media.save
+    assert t.update_original_sizes
+    assert_equal t.original_width, 1920
+    assert_equal t.original_height, 1200
+  end
 end