init.lua for hammerspoon... tap caps lock for escape, hold for ctrl, shift and caps lock tap sends shift escape

init.lua

-- adapted from https://gist.github.com/arbelt/b91e1f38a0880afb316dd5b5732759f1
-- if shift key is held during a caps lock tap, send shift-escape
ctrl_table = {
    send_escape = true,
    last_mods = {}
}

control_key_timer = hs.timer.delayed.new(0.15, function()
    ctrl_table["send_escape"] = false
    -- log.i("timer fired")
    -- control_key_timer:stop()
end
)

last_mods = {}

control_handler = function(evt)
  local new_mods = evt:getFlags()
  if last_mods["ctrl"] == new_mods["ctrl"] then
      return false
  end
  if not last_mods["ctrl"] then
    -- log.i("control pressed")
  	if last_mods["shift"] then
		ctrl_table["send_shift"] = true
	end
    last_mods = new_mods
    ctrl_table["send_escape"] = true
    -- log.i("starting timer")
    control_key_timer:start()
  else
    -- log.i("contrtol released")
    -- log.i(ctrl_table["send_escape"])
    if ctrl_table["send_escape"] then
	  local sendWith = {};
      -- log.i("send escape key...")
	  if last_mods["shift"] then
		  sendWith = {"shift"}
	  end
      hs.eventtap.keyStroke(sendWith, "ESCAPE")
    end
    last_mods = new_mods
    control_key_timer:stop()
  end
  return false
end

control_tap = hs.eventtap.new({12}, control_handler)

control_tap:start()