module Sinatra::Helpers

def uri(addr = nil, absolute = true, add_script_name = true)
  return addr if addr =~ /\A[A-z][A-z0-9\+\.\-]*:/
  uri = [host = ""]
  if absolute
    host << "http#{'s' if request.secure?}://"
    if request.forwarded? or request.port != (request.secure? ? 443 : 80)
      host << request.host_with_port
    else
      host << request.host
    end
  end
  uri << request.script_name.to_s if add_script_name
  uri << (addr ? addr : request.path_info).to_s
  File.join uri
end