detecting an enc stop

enc_stop.lua

screen_dirty = true

function init()
  message = {"e1 ready","e2 ready","e3 ready"}
  counters = {}
  waiting_indicator_max = 100
  wait_length_in_seconds = .5
  for e = 1,3 do
    reset_counter(e)
  end
  
  indicator = metro.init()
  indicator.time = wait_length_in_seconds / waiting_indicator_max
  indicator.count = -1
  indicator.play = 1
  indicator.event = update_lengths
  indicator:start()
  
  clock.run(screen_redraw_clock)
  redraw()
end

function reset_counter(e)
  counters[e] = {
    this_clock = nil,
    length = 0,
    waiting = false
  }
end

function update_lengths()
  for e = 1,3 do
    if counters[e]["waiting"] then
      counters[e]["length"] = counters[e]["length"] - 1
      screen_dirty = true
    end
  end
end

function enc(e,d)
  if counters[e]["this_clock"] ~= nil then
    clock.cancel(counters[e]["this_clock"])
    reset_counter(e)
  end
  message[e] = "turning: e" .. e
  counters[e]["length"] = waiting_indicator_max
  
  screen_dirty = true
  if counters[e]["this_clock"] == nil then
    counters[e]["this_clock"] = clock.run(wait, e)
  end
end

function wait(e)
  counters[e]["waiting"] = true
  clock.sleep(wait_length_in_seconds)
  counters[e]["waiting"] = false
  counters[e]["this_clock"] = nil
  message[e] = "stopped: e" .. e
  screen_dirty = true
end


function redraw()
  screen:clear()
  screen.level(15)  
  for i = 1,3 do
    local y =  22 + (12*i)
    screen.move(0, y)
    screen.text(message[i])
    screen.move(0, y + 4)
    screen.line_rel(counters[i]["length"], 0)
    screen.stroke()
  end
  screen:update()
end

function screen_redraw_clock()
  while true do
    if screen_dirty then
      redraw()
      screen_dirty = false
    end
    clock.sleep(1/30)
  end
end