//https://blog.csdn.net/Y_xianlin/article/details/141708176

#include <SPI.h>
#include <MFRC522.h>

// 定义RC522模块的引脚
#define SS_PIN    7 // SDA
#define RST_PIN   3 // RST

// 创建MFRC522对象
MFRC522 mfrc522(SS_PIN, RST_PIN);


MFRC522::MIFARE_Key key; // 密钥

int blockAddrs[2] = {1,2};// 数据块

String errorValue = "r:rfid error";
String notRfid = "r:not rfid";
String writeValue = "r:write ok";

void rfidSetup(){

  SPI.begin(); // 初始化SPI总线
  mfrc522.PCD_Init(); // 初始化MFRC522模块

  // 初始化密钥（全为0xFF）
  for (byte i = 0; i < 6; i++) {
    key.keyByte[i] = 0xFF;
  }
  
  Serial.println("RFID init ok...");

}


String readRFID(int index){

 int blockAddr = blockAddrs[index];

  // 认证指定扇区
  MFRC522::StatusCode status = mfrc522.PCD_Authenticate(MFRC522::PICC_CMD_MF_AUTH_KEY_A, blockAddr, &key, &(mfrc522.uid));

  if (status != MFRC522::STATUS_OK) {
    Serial.println("rfid error"); //认证失败
    return errorValue;
  }
 
  // 读取扇区数据
  byte buffer[18];
  byte size = sizeof(buffer);
  status = mfrc522.MIFARE_Read(blockAddr, buffer, &size);
  if (status != MFRC522::STATUS_OK) {
    Serial.println("rfid error"); //认证失败
    return errorValue;
  }
 

  String str = "";
  for (byte i = 0; i < 15; i++) {

    str += (char)buffer[i];
  }
  
  Serial.println("read:" + str);
  return str;
}

void readRFID() {

  // 检查是否有新的RFID标签
  if (!mfrc522.PICC_IsNewCardPresent()) {
    Serial.println("not rfid"); //没rfid
    pCharacteristic->setValue(notRfid.c_str());
    return;
  }
 
  // 选择其中一个RFID标签
  if (!mfrc522.PICC_ReadCardSerial()) {
    Serial.println("rfid fail"); //失败
    pCharacteristic->setValue(errorValue.c_str());
    return;
  }

  String str = "";

  for(int i=0;i<2;i++){

    String strData = readRFID(i);

    if(strData==errorValue){

      pCharacteristic->setValue(errorValue.c_str());

      // 停止与标签的通信
      mfrc522.PICC_HaltA();
      mfrc522.PCD_StopCrypto1();
      return;

    }else{

      str = str + strData;
    }
    
  }

  str = "r:" + str;
  Serial.println(str);
  pCharacteristic->setValue(str.c_str());
 
  // 停止与标签的通信
  mfrc522.PICC_HaltA();
  mfrc522.PCD_StopCrypto1();
}

String writeRFID(String data,int index){

   if(index>=2)return writeValue;

   int blockAddr = blockAddrs[index];

   int strLen = data.length() - index*15;

   if(strLen<=0)return writeValue;

   if(strLen>15)strLen=15;

   String strData = data.substring(index*15, index*15 + strLen);

   Serial.print("write data: ");
   Serial.println(strData);

  // 将数据转化为字节数组（最多16字节）
  byte dataBlock[16];
  strData.getBytes(dataBlock, 16);
 
  // 认证指定扇区
  MFRC522::StatusCode status = mfrc522.PCD_Authenticate(MFRC522::PICC_CMD_MF_AUTH_KEY_A, blockAddr, &key, &(mfrc522.uid));

  if (status != MFRC522::STATUS_OK) {
    Serial.println("rfid error"); //认证失败
    return errorValue;
  }
 
  // 写入数据到指定块
  status = mfrc522.MIFARE_Write(blockAddr, dataBlock, 16);

  if (status != MFRC522::STATUS_OK) {
    Serial.println("rfid error"); //写入失败
    return errorValue;
  } else {
    Serial.println("rfid ok"); //写入成功
    return writeValue;
  }
  

}
 
void writeRFID(String data) {

  // 检查是否有新的RFID标签
  if (!mfrc522.PICC_IsNewCardPresent()) {
    Serial.println("not rfid"); //没rfid
    pCharacteristic->setValue(notRfid.c_str());
    return;
  }
 
  // 选择其中一个RFID标签
  if (!mfrc522.PICC_ReadCardSerial()) {
    Serial.println("rfid fail"); //失败
    pCharacteristic->setValue(errorValue.c_str());
    return;
  }
  
 
  String strData = "";

  int len = data.length()/15;
  if(data.length()%15>0)len=len+1;

  for(int i=0;i<len;i++){

    strData = writeRFID(data,i);
  }

  pCharacteristic->setValue(strData.c_str());
 
  // 停止与标签的通信
  mfrc522.PICC_HaltA();
  mfrc522.PCD_StopCrypto1();
}

//0:开头字符串读取 1:开头字符串写入
void rifdCommand(){

    String command = pCharacteristic->getValue().c_str();

    if (command.startsWith("0:")) {

      readRFID();

    } else if (command.startsWith("1:")) {

      String data = command.substring(2);

      if(data.length()<=30){
        writeRFID(data);
      }
      
    }
}

int loopRfidSize=1000; //loop间隔
int rfidMillisTime;
void rfidLoop(){

  //1秒读取一次指令
  int rfidTimeCurrent = millis();
  
  if(rfidTimeCurrent<=0)rfidMillisTime = rfidTimeCurrent;

  if((rfidTimeCurrent - rfidMillisTime)>loopRfidSize){

    rfidMillisTime = rfidTimeCurrent;
    rifdCommand();
  }

}