---

local function rujos()
  term.clear()
  term.setCursorPos(1,1)
  print 'Booting J:OS 1.7 Beta'
  sleep(1)
end

local function bootcraft()
  term.clear()
  term.setCursorPos(4,4)
  print 'booting CraftOS 1.7'
  sleep(1)
end

local function rejos()
  term.clear()
  term.setCursorPos(1,1)
  print 'Removing J:OS 1.7 Beta'
  sleep(1)
end

local w,h = term.getSize()
local options = {
  {'Run-J:OS',4,4,rujos};
  {'Boot-CraftOS',4,5,bootcraft};
  {'Remove-J:OS',4,5,rejos};
}

local selection = 1

while true do
  term.clear()

  for i, option in pairs(options) do
        if selection == i then
          term.setCursorPos(option[2] - 2, option[3])
          write '['
          term.setCursorPos(option[2] + #option[1] + 1, option[3])
          write ']'
        end

        term.setCursorPos(option[2], option[3])
        write(option[1])
  end

  local _, k = os.pullEvent('key')
  if k == keys.down then
        selection = (selection < #options)
        and selection + 1
        or 1
  elseif k == keys.up then
        selection = (selection > 1)
        and selection - 1
        or #options
  elseif k == keys.enter then
        local o = options[selection]
        local res = o[4] and o[4]() or true
        if res == false then
          break
        end
  end
end