NetBIOS

function component.isAvailable(target)
  return component.list(target)() ~= nil
end

function computer.getBootAddress()
  return __BIOS_DATA:sub(1, 36)
end

setmetatable(component, {
  ["__index"] = function(_, key)
    if component.isAvailable(key) then
      return component.proxy(component.list(key)())
    end
  end
})

local eeprom = component.eeprom

__BIOS_PXE = component.modem ~= nil
__BIOS_TARGET = ""
__BIOS_SERVER = ""
__BIOS_DATA = eeprom.getData()
__BIOS_LEGACY = (__BIOS_DATA ~= "" and type(__BIOS_DATA == "string")) and #__BIOS_DATA == 36

event = {}
local stack = {}
local listeners = {}
function event.pull(filter)
 if not filter then return table.remove(stack,1)
 else
  for _,v in pairs(stack) do
   if v == filter then
    return v
   end
  end
  repeat
   t=table.pack(computer.pullSignal())
   evtype = table.remove(t,1)
   if listeners[evtype] ~= nil then
    for k,v in pairs(listeners[evtype]) do
     local evt = pcall(v,evtype,table.unpack(t))
    end
   end
  until evtype == filter
  return evtype, table.unpack(t)
 end
end

if __BIOS_DATA:sub(37, 41) == ":http" then
  if component.isAvailable("internet") then
    local url = __BIOS_DATA:sub(38, #__BIOS_DATA)
    local internet = component.internet
    local req = internet.request(url)
    repeat
      local success, connected = pcall(req.finishConnect)
    until success and connected
    __BIOS_TARGET = req.read()
    __BIOS_PXE = false
end

if __BIOS_DATA:sub(37, 38) == ":/" or (__BIOS_LEGACY and __BIOS_PXE) then
  local targetAddr = __BIOS_DATA:sub(1, 36)
  local targetFile = __BIOS_DATA:sub(38, #__BIOS_DATA)

  __BIOS_ROOT = component.proxy(targetAddr)
  local handle = __BIOS_ROOT.open(targetFile or __BIOS_LEGACY and "/init.lua")
  __BIOS_TARGET = __BIOS_ROOT.read(handle, math.huge)
  __BIOS_PXE = false
  end
end

if __BIOS_PXE then
  local modem = component.modem

  local function status(msg, ...)
    modem.broadcast(2412, msg, ...)
  end

  modem.open(2412)
  status("PXE_READY")

  repeat
    local _, _, addr, _, _, status = event.pull("modem_message")
    __PXE_SERVER = addr
  until status == "PXE_CONNECT"
  status = nil

  repeat
    local _, _, from, _, _, partial = event.pull("modem_message")
    if (from ~= __PXE_SERVER) then
      do break end
    end
    __BIOS_TARGET = __BIOS_TARGET .. partial
  until partial == ""
end

return load(__BIOS_TARGET)()