function delay_s(delay)
   delay = delay or 1
   local time_to = os.time() + delay
   while os.time() < time_to do end
end

function run(msg, matches)
  local lat = matches[1]
  local lon = matches[2]
  local receiver = get_receiver(msg)

  local zooms = {16, 18}

  for i = 1, #zooms do
    local zoom = zooms[i]
    local url = "http://maps.googleapis.com/maps/api/staticmap?zoom=" .. zoom .. "&size=600x300&maptype=roadmap&center=" .. lat .. "," .. lon .. "&markers=color:blue%7Clabel:X%7C" .. lat .. "," .. lon
    local file = download_to_file(url)
    send_photo(receiver, file, ok_cb, false)
    delay_s(2)
  end

  return "www.google.es/maps/place/@" .. lat .. "," .. lon
end

return {
    description = "generates a map showing the given GPS coordinates", 
    usage = "!gps latitude,longitude",
    patterns = {"^!gps ([^,]*)[,%s]([^,]*)$"}, 
    run = run 
}