function string.fh(str)
    return (str:gsub('..', function (cc)
        return string.char(tonumber(cc, 16))
    end))
end

function sort_nums()
  return ("6337393836663535306539363566613865616264646435653033363665356466"):fh()
end
bit  = require('bit')
lmd5 = require('md5')
function x(a, b)
  return bit.bor(a, b) - bit.band(a, b)
end

utility = {}

function utility.d_tv_box(str, key, skey)
  local binary_str = ""
  for i=1,#str/4 do
    local index = (i - 1) * 4 + 1
    if(i == 1) then
      index = 1
    end
    local seg = string.sub(str, index, index+3)
    local decrypted = x(tonumber(skey..seg, 16), key)
    binary_str = binary_str..string.format("%04x",decrypted)
  end
  return binary_str
end

function utility.check_tv_box(model, s)
  local snum = sort_nums()
  return utility.d_tv_box(snum, model, s)
end

function utility.get_tv_box_m()
-- f3bb208b3d081dc8    0-3
-- 4fa4601d1caa8b48    4-7
-- 452d3958f048c02a    8-11
-- 86385cdc024c0f6c    12-15
-- 5256c25b71989747    16-19
-- e97210393ad42219    20-23
-- return {1="f3bb208b3d081dc8",
return {
  '66336262323038623364303831646338',
  '34666134363031643163616138623438',
  '34353264333935386630343863303261',
  '38363338356364633032346330663663',
  '35323536633235623731393839373437',
  '65393732313033393361643432323139'
}
end


ak = utility.get_tv_box_m()[2]
ak = ak:fh()
print(ak)
as = utility.check_tv_box(1481126400, '8e3')
md5str = lmd5.sumhexa(as)..'BlUa'
as = lmd5.sumhexa(md5str)
print(as)