dyutils = require("dyutils")
bit = require("bit")
lpack = require("lua_pack")
cjson = require("cjson")
base64 = require("base64")
syslog = require("syslog")
bcd = require("bcd")
sqlite3 = require("lsqlite3")
bnot = bit.bnot
band, bor, bxor = bit.band, bit.bor, bit.bxor
lshift, rshift, rol = bit.lshift, bit.rshift, bit.rol

last_report = 0
INTERVAL=10

function protocol_encode(json_str, len)
  local err_code=0
  --取出入参--
  local obj=cjson.decode(json_str)
  local id=obj.identifier
  --编码--
  local result = {}
  local sn=obj.sn

  if (id == "conn") then
    result['UUID'] = "FFF2"
    result['data'] = "CC80020301010001"
  elseif (id == "start") then
    result['UUID'] = "FFF2"
    result['data'] = "CC80020301020002"
  end
  result['sn'] = sn

  json_str=cjson.encode(result)
  return 8192,json_str,#json_str
end

function protocol_decode(input_str, len)
  local err_code=0
  local now = os.time()
  --取出入参--
  local obj={}
  local input_obj=cjson.decode(input_str)
  local bin_str=input_obj.raw_data
  --入参中的raw_data的二进制转换--
  local t_str=''
  for i=1,#bin_str,2 do
     t_str=t_str .. string.char(tonumber(string.sub(bin_str, i, i+1),16))
  end
  bin_str=t_str
  local data_obj = cjson.decode(bin_str)
  obj['sn'] = data_obj['sn']
  local uuid = data_obj['uuid']
  local data_str = data_obj['data_str']
  --print (data_str)

  local data_bin=''
  for i=1,#data_str,2 do
    data_bin=data_bin .. string.char(tonumber(string.sub(data_str, i, i+1),16))
  end

  _,pre,ver,len,type,sub_type = bunpack(data_bin, ">S1C4")

  if pre ~= 0xAA80 then
    print("precode not right "..pre)
    return 0, nil, 0
  end

  if type == 1 then
    if sub_type == 5 then
        if now < last_report + INTERVAL then
            return 0,nil,0
        end
        last_report = now
        _,_,PH,_,_,PL,_ = bunpack(string.sub(data_bin, 7), "C6")
        p = PH * 256 + bxor(PH, PL)
        obj['blood_pressure'] = p
        obj['identifier'] = "blood_pressure"
    elseif sub_type == 6 then
        obj['identifier'] = "final_result"
        _,c1,c2,c3,c4,c5,c6 = bunpack(string.sub(data_bin, 14), "C6")
        obj['systolic'] = c1 * 256 + c2
        obj['diastolic'] = c3 * 256 + c4
        obj['PUL'] = c5 * 256 + c6
    end

  elseif type == 4 then

  end

  --出参格式化--
  local json_str=cjson.encode(obj)
  --print(err_code, json_str, #json_str)
  return err_code,json_str,#json_str
end


--protocol_decode(' {"raw_data":"7B22646174615F737472223A20226161383030323038303130353030303030303030323930303237222C2022736E223A20224F79397468556479222C202275756964223A202230303030666666312D303030302D313030302D383030302D303038303566396233346662227D","identifier":""}', 0)