#include "codec_slave.h"
#include "base/crc.h"

myarray codec_slave::encode(int srcAddr, int dstAddr, int cmd, myarray data)
{
  Q_UNUSED(srcAddr);
  myarray t;
  uint16_t len = data.size() + 10;
  cmd_no++;

  t.append('Y');
  t.append('e');
  t.append(len & 0xff);
  t.append(len >> 8);
  t.append(char(0));              // 源地址
  t.append(char(dstAddr & 0xff)); // 目标地址
  t.append(cmd);                  // 命令码
  t.append(cmd_no & 0xff);
  t.append(cmd_no >> 8);
  t.append(data);
  t.append(crc::crc8((uint8_t *)t.data(), t.size()));
  return t;
}

myarray codec_slave::decode(int &srcAddr, int &dstAddr, int &cmd, myarray data)
{
  myarray r;
  QString str_err = "ok";

  if(data.size()==1){
    srcAddr = data[0];
    dstAddr = 0;
    r.append(char(0));
    return r;
  }

  if (data.size() < 10)
  {
    // 一帧数据至少10字节
    qWarning("recv data len too less");
    str_err = "recv data len too less.";
    return r;
  }
  uint16_t len = data[2] | (data[3] << 8);
  uint8_t crc = crc::crc8((uint8_t *)data.data(), data.size() - 1);
  if (len != data.size())
  {
    // 如果长度不相等则产生了数据丢失
    qWarning("recv data have lossed");
    str_err = "recv data have lossed.";
    return r;
  }
  srcAddr = data[4];
  dstAddr = data[5];
  uint16_t no = data[7] | (data[8] << 8);
  uint16_t h_no = cmd_no;
  if (no != h_no)
  {
    // 发送一条指令应等待其返回，此时流水号应相同
    // qWarning()<<"alave_addr="<<src_addr<<" cmd_no error:host="<<h_no<<",slave="<<no<<endl;
    // return r;
    // str_err="cmd no err.";
  }
  if (crc != uint8_t(data[len - 1]))
  {
    // crc校验不对
    qWarning("recv data crc check error:%02x,%02x", crc, uint8_t(data[len - 1]));
    qWarning("data=%s", data.toHex(' ').data());
    str_err = "crc check err.";
  }
  cmd = data[6];
  r = data.mid(9, len - 10);
  return r;
}

Codec *codec_slave_get()
{
  static Codec *codec_ = nullptr;
  if (codec_ == nullptr)
  {
    codec_ = new codec_slave();
  }
  return codec_;
}

codec_export(codec_slave, codec_slave_get);