-- This is released into the public domain.
-- No warranty is provided, implied or otherwise.

-- svc-vdrslamp.lua : Virtual Redstone Lamp
-- Authors: 20kdc

local vdev = neo.requireAccess("x.svc.virtudev", "lamp dev")

local evr = neo.requireAccess("x.neo.pub.window", "the lamp")
local wnd = evr(12, 6)

local bLine = (" "):rep(12)

local function blank()
 return 0
end

local total = 0

vdev.install({
 type = "redstone",
 address = "vdrslamp-" .. neo.pid,
 slot = 0,
 getWakeThreshold = blank,
 setWakeThreshold = blank,
 getInput = blank,
 getOutput = function (i)
  return total
 end,
 setOutput = function (i, v)
  total = v
  wnd.setSize(12, 6)
 end
})

while true do
 local e = {coroutine.yield()}
 if e[1] == "x.neo.pub.window" then
  if e[3] == "close" then
   -- the ignorance of unregistration is deliberate
   -- a working impl. will properly recover
   return
  elseif e[3] == "line" then
   local bg = 0xFFFFFF
   if total == 0 then bg = 0 end
   wnd.span(1, e[4], bLine, bg, bg)
  end
 end
end