#include <Arduino.h>
#include <OneWire.h>

// 与你原代码一致：GPIO5
#define ONE_WIRE_BUS 5

OneWire oneWire(ONE_WIRE_BUS);

// 保存第一个设备的 ROM（不再只限 0x28）
uint8_t g_rom[8];
bool    g_found = false;
uint8_t g_family = 0x00; // 0x28=DS18B20, 0x10=DS18S20, 0x22=DS1822

static void printRom(const uint8_t rom[8]) {
  for (int i = 0; i < 8; i++) {
    Serial.printf("%02X", rom[i]);
    if (i != 7) Serial.print(":");
  }
  Serial.println();
}

// 扫描总线，记录第一个有效 ROM（CRC 过）
bool findFirstDeviceAnyFamily() {
  oneWire.reset_search();
  uint8_t addr[8];
  while (oneWire.search(addr)) {
    if (OneWire::crc8(addr, 7) != addr[7]) continue; // ROM CRC fail
    memcpy(g_rom, addr, 8);
    g_family = addr[0];
    return true;
  }
  return false;
}

// 触发温度转换（外接供电：第二个参数 0；若寄生电源，改为 1）
bool convertT_blocking(uint32_t timeout_ms = 1000) {
  if (!g_found) return false;
  if (!oneWire.reset()) return false;   // presence
  oneWire.select(g_rom);                // Match ROM
  oneWire.write(0x44, 0);               // Convert T（0=不强上拉）

  unsigned long t0 = millis();
  while (millis() - t0 < timeout_ms) {
    if (oneWire.read_bit() == 1) return true; // 1=完成
    delay(2);
  }
  return false; // 超时
}

// 读 Scratchpad（9 字节，校验前 8 字节 CRC 对第 9 字节）
bool readScratchpad(uint8_t sp[9]) {
  if (!g_found) return false;
  if (!oneWire.reset()) return false;
  oneWire.select(g_rom);
  oneWire.write(0xBE); // Read Scratchpad
  for (int i = 0; i < 9; i++) sp[i] = oneWire.read();
  return OneWire::crc8(sp, 8) == sp[8];
}

// 统一的温度解码：兼容 0x28 / 0x22 / 0x10
bool decodeTemperatureC(const uint8_t sp[9], uint8_t family, float &celsius) {
  if (family == 0x28 || family == 0x22) {
    // DS18B20 / DS1822: 1/16 °C
    int16_t raw = (int16_t)((sp[1] << 8) | sp[0]);
    celsius = raw / 16.0f;
    if (fabsf(celsius - 85.0f) < 0.0001f) return false;
    return true;
  } else if (family == 0x10) {
    // DS18S20 (9-bit base), 使用 Count Per C 和 Count Remain 细化
    int16_t raw = (int16_t)((sp[1] << 8) | sp[0]);
    int16_t integer_part = (raw >> 1);             // 去掉0.5位后的整数部分
    uint8_t countRemain = sp[6];
    uint8_t countPerC   = sp[7];
    if (countPerC == 0) return false;              // 防止除零
    celsius = (float)integer_part - 0.25f
              + (float)(countPerC - countRemain) / (float)countPerC;
    if (fabsf(celsius - 85.0f) < 0.0001f) return false;
    return true;
  } else {
    // 其它family，先按B20方式尝试
    int16_t raw = (int16_t)((sp[1] << 8) | sp[0]);
    celsius = raw / 16.0f;
    return true;
  }
}


void setup() {
  Serial.begin(115200);
  // 与你原例一致：空闲用内部上拉；若有物理 4.7k 外部上拉，可换 INPUT
  pinMode(ONE_WIRE_BUS, INPUT_PULLUP);

  Serial.println("Dallas Temperature IC Control (OneWire-only, any family) Demo");
  // 连续尝试几次扫描，避免上电瞬间找不到
  for (int i = 0; i < 5 && !g_found; ++i) {
    g_found = findFirstDeviceAnyFamily();
    if (!g_found) { delay(200); }
  }

  if (g_found) {
    Serial.print("Found device ROM: ");
    printRom(g_rom);
    Serial.print("Family code: 0x"); Serial.println(g_family, HEX);
  } else {
    Serial.println("No 1-Wire device found on the bus!");
  }
}

void loop() {
  if (!g_found) {
    // 每秒重试扫描一次
    g_found = findFirstDeviceAnyFamily();
    if (g_found) {
      Serial.print("Found device ROM: ");
      printRom(g_rom);
      Serial.print("Family code: 0x"); Serial.println(g_family, HEX);
    } else {
      delay(1000);
      return;
    }
  }

  Serial.print("Requesting temperatures...");
  bool ok = convertT_blocking();
  if (!ok) {
    Serial.println("FAILED");
    delay(500);
    return;
  }
  Serial.println("DONE");

  uint8_t sp[9];
  if (!readScratchpad(sp)) {
    Serial.println("Read failed (scratchpad CRC).");
    delay(500);
    return;
  }

  float tC = NAN;
  if (decodeTemperatureC(sp, g_family, tC)) {
    Serial.print("Temperature for the device 1 (index 0) is: ");
    Serial.println(tC); // 摄氏度
  } else {
    Serial.println("Read failed (decode).");
  }

  delay(500);
}