return function(con)

local buf = {''}

function con.keydown(k)
  if k == 'backspace' then
    if #buf[#buf] > 0 then con.bs() end
  elseif k == 'return' then
    con.type '\n'
    table.insert(buf, '')
  end
end

function con.popbuf(line)
  local v = buf[#buf-1] or ''
  if line then
    if v:sub(-1) == '\n' then
      buf[#buf-1] = ''
      return v:sub(1, -2)
    end
  else
    buf[#buf] = bs(buf[#buf])
    v = v:sub(1,1)
  end
  return nil
end

function con.type(text)
  buf[#buf] = buf[#buf].. text
  con.print(text)
end

local function bs(v)
  local off = utf8.offset(v, -1)
  if off then v = v:sub(1, off - 1) end
  return v, off ~= nil
end

function con.bs()
  buf[#buf] = bs(buf[#buf])
  con.out[#con.out] = bs(con.out[#con.out])
end

function con.cls()
  buf = {''}
  con.text = {''}
  con.oy = 0
  con.reszT()
end

function con.ret()
  table.insert(con.out, '')
end

local function conc(a, b)
  return tostring(a)..tostring(b)
end

function con.print(text)
  for i, v in utf8.codes(tostring(text)) do
    v = utf8.char(v)
    if     v == '\n' then con.ret()
    elseif v == '\b' then con.bs()
    -- \r\t\v is in loop.lua
    else con.out[#con.out] = conc(con.out[#con.out],v)
    end
  end
  con.reszT()
end

function con.println(text)
  con.print(conc(text,'\n'))
end

end