module Github::MimeType

def lookup_media(name)
  MEDIA_LOOKUP.fetch(name) do
    raise ArgumentError, "Provided Media Type #{name} is not valid"
  end
end

def parse(media)
  version = 'v3'
  media.sub!(/^[.]*|[.]*$/,"")
  media = media.include?('+') ? media.split('+')[0] : media
  version, media = media.split('.') if media.include?('.')
  media_type = lookup_media(media)
  "application/vnd.github.#{version}.#{media_type}"
end