Mode = 'version_check'

-- available modes: run, error
Mode = 'run'
Error_message = nil
Error_count = 0
-- we'll reuse error mode on load for an initial version check

  -- version check

  if array.find(Supported_versions, Version) then
    Mode = 'run'

  if array.find(Supported_versions, Version) == nil then
    Mode = 'error'
    Error_message = ("This app doesn't support version %s; please use version %s. Press any key to try it with this version anyway."):format(Version, Supported_versions[1])
    print(Error_message)
    -- continue initializing everything; hopefully we won't have errors during initialization

  -- listen for commands in both 'error' and 'run' modes

      Mode = 'run'

  if on.update then on.update(dt) end

  if Mode == 'run' then
    if on.update then on.update(dt) end
  end

  if Mode == 'version_check' then

  if Mode == 'error' then

    love.graphics.print(("This app doesn't support version %s; please use version %s. Press any key to try it with this version anyway."):format(Version, Supported_versions[1]), 40, 40)

    love.graphics.printf(Error_message, 40, 40, 600)

  if Mode == 'version_check' then return end

  if Mode == 'error' then return end

  if Mode == 'version_check' then return end

  if Mode == 'error' then return end

  if Mode == 'version_check' then return end

  if Mode == 'error' then return end

  if Mode == 'version_check' then return end

  if Mode == 'error' then return end

  if Mode == 'version_check' then return end

  if Mode == 'error' then
    if key == 'c' then
      love.system.setClipboardText(Error_message)
    end
    return
  end

  if Mode == 'version_check' then return end

  if Mode == 'error' then return end

  if Mode == 'version_check' then

  if Mode == 'error' then

  if Mode == 'version_check' then return end

  if Mode == 'error' then return end

  if Mode == 'version_check' then return end

  if Mode == 'error' then return end

  if Mode == 'version_check' then return end

  if Mode == 'error' then return end

  -- draw a pause indicator on screen
  love.graphics.setColor(1,0,0)
  love.graphics.rectangle('fill', 10,10, 3,10)
  love.graphics.rectangle('fill', 16,10, 3,10)
  love.graphics.present()
  -- print stack trace here just in case we ran the app through a terminal

  Mode = 'error'

  print(stack_trace)
  print('Look in the driver for options to investigate further.')
  print("(You probably can't close the app window at this point. If you don't have the driver set up, you might need to force-quit.)")
  -- send stack trace to driver and wait for a response

  local buf
  repeat
    buf = app.receive()
    love.timer.sleep(0.001)
  until buf
  if buf == 'QUIT' then
    return true

  Error_message = 'Something is wrong. Sorry!\n\n'..stack_trace..'\n\n'..
    "(Note: function names above don't include outer tables. So functions like on.draw might show up as just 'draw', etc.)\n\n"..
    'Options:\n'..
    '- press "c" (without the quotes) to copy this message to your clipboard to send to me: ak@akkartik.com\n'..
    '- press any other key to retry, see if things start working again\n'..
    '- run driver.love to try to fix it yourself. As you do, feel free to ask me questions: ak@akkartik.com\n'
  Error_count = Error_count+1
  if Error_count > 1 then
    Error_message = Error_message..('\n\nThis is error #%d in this session; things will probably not improve in this session. Please copy the message and send it to me: ak@akkartik.com.'):format(Error_count)

  app.run(buf)

  print(Error_message)