function scroll_to(splash, x, y)
  local js = string.format(
    "window.scrollTo(%s, %s);", 
    tonumber(x), 
    tonumber(y)
  )
  return splash:runjs(js)
end


function get_doc_height(splash)
  return splash:runjs([[
    Math.max(
        Math.max(document.body.scrollHeight, document.documentElement.scrollHeight),
        Math.max(document.body.offsetHeight, document.documentElement.offsetHeight),
        Math.max(document.body.clientHeight, document.documentElement.clientHeight)
    )
  ]])
end


function scroll_to_bottom(splash)
  local y = get_doc_height(splash)
  return scroll_to(splash, 0, y)
end


function main(splash)

  -- e.g. http://infiniteajaxscroll.com/examples/basic/page1.html
  local url = splash.args.url
  assert(splash:go(url))
  assert(splash:wait(0.5))
  splash:stop()
  
  for i=1,10 do
    scroll_to_bottom(splash)    
    assert(splash:wait(0.2))
  end

  splash:set_viewport("full")

  return {
    html = splash:html(),
    png = splash:png{width=640},
    har = splash:har(),
  }
end