Love2d Konami Code module

konami.lua

--[[
Example use:

function love.keypressed(key)
  konami(key, function()
    love.window.showMessageBox("Konami", "the konami code was entered")
  end)
end
]]
local MAX_DELAY = 1.5
local last_key_t = 0
local sequence = {"up", "up", "down", "down", "left", "right", "left", "right", "b", "a", "return"}
local i = 1

return function(key, callback)
  local t = love.timer.getTime()
  if (t - last_key_t) > MAX_DELAY then
    i = 1
  end

  if sequence[i] == key then
    last_key_t = t
    i = i + 1
    if i > #sequence then
      callback()
    end
  else
    i = 1
  end
end