#include <WiFi.h>
#include <PubSubClient.h>
#include <ArduinoJson.h>
#include "DHT.h"

// ================= 网络与云平台配置 =================
const char* ssid = "Wokwi-GUEST"; // Wokwi 默认的虚拟 WiFi，不要改
const char* password = "";        // Wokwi 虚拟 WiFi 没有密码，不要改

const char* mqtt_server = "bemfa.com"; // 巴法云 MQTT 服务器地址
const int mqtt_port = 9501;            // 巴法云 MQTT 端口号
const char* client_id = "79ac2469ffbc41019518463ec32ced08"; // 替换成你控制台里的 UID！
const char* topic = "WaterMonitor";       // 替换成你在巴法云新建的主题名字！

WiFiClient espClient;
PubSubClient client(espClient);

// ================= 硬件引脚定义 =================
#define DHTPIN 4       
#define DHTTYPE DHT22  
DHT dht(DHTPIN, DHTTYPE);

const int potPin = 34;      
const int ledPin = 2;       
const int buzzerPin = 5;    

// ================= 状态追踪变量 =================
unsigned long flowStartTime = 0;
float baselineHumidity = 0.0;
bool isTracking = false;
bool isAlarming = false;
unsigned long lastMsgTime = 0; // 上次发送 MQTT 消息的时间

// 连接 WiFi 的函数
void setup_wifi() {
  delay(10);
  Serial.println();
  Serial.print("正在连接 WiFi: ");
  Serial.println(ssid);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nWiFi 连接成功！");
}

// 连接 MQTT 服务器的函数
void reconnect() {
  while (!client.connected()) {
    Serial.print("尝试连接 MQTT 云端...");
    if (client.connect(client_id)) {
      Serial.println("连接成功！");
    } else {
      Serial.print("失败，状态码=");
      Serial.print(client.state());
      Serial.println("，5秒后重试");
      delay(5000);
    }
  }
}

void setup() {
  Serial.begin(9600);
  setup_wifi();
  client.setServer(mqtt_server, mqtt_port);
  
  dht.begin();
  pinMode(ledPin, OUTPUT);
  pinMode(buzzerPin, OUTPUT);
  digitalWrite(ledPin, LOW);
  digitalWrite(buzzerPin, LOW);
}

void loop() {
  if (!client.connected()) {
    reconnect();
  }
  client.loop(); // 保持 MQTT 底层心跳机制

  unsigned long currentMillis = millis(); 
  
  // 1. 读取传感器 (ESP32 的 ADC 是 12 位的，最大值 4095)
  int potValue = analogRead(potPin);
  float currentFlow = (potValue / 4095.0) * 5.0; 
  float currentHumidity = dht.readHumidity();

  if (isnan(currentHumidity)) {
    return; // 读取失败暂不处理，防止程序崩溃
  }

  // 2. 核心状态机逻辑 (完全保留阶段一的判断)
  if (currentFlow > 0.2) {
    if (!isTracking) {
      isTracking = true;
      flowStartTime = currentMillis;
      baselineHumidity = currentHumidity;
    } else {
      unsigned long elapsed = currentMillis - flowStartTime;
      float deltaHumidity = currentHumidity - baselineHumidity;

      if (!isAlarming) {
        if (elapsed >= 5000) {
          if (elapsed <= 10000) {
            if (deltaHumidity >= 10.0) {
              isAlarming = true; // 触发漏水报警！
            }
          } else {
            flowStartTime = currentMillis;
            baselineHumidity = currentHumidity;
          }
        }
      }
    }
  } else {
    isTracking = false;
    isAlarming = false;
  }

  // 执行声光报警动作
  if (isAlarming) {
    if ((currentMillis % 200) < 100) {
      digitalWrite(ledPin, HIGH);
      digitalWrite(buzzerPin, HIGH);
    } else {
      digitalWrite(ledPin, LOW);
      digitalWrite(buzzerPin, LOW);
    }
  } else {
    digitalWrite(ledPin, LOW);
    digitalWrite(buzzerPin, LOW);
  }

  // 3. 每隔 1 秒，将数据打包成 JSON 推送到云端
  if (currentMillis - lastMsgTime > 1000) {
    lastMsgTime = currentMillis;

    // 创建 JSON 对象
    StaticJsonDocument<200> doc;
    doc["flow"] = currentFlow;
    doc["humidity"] = currentHumidity;
    doc["alarm"] = isAlarming;

    // 将 JSON 序列化为字符串
    char jsonBuffer[256];
    serializeJson(doc, jsonBuffer);

    // 通过 MQTT 发布出去
    client.publish(topic, jsonBuffer);
    
    Serial.print("[MQTT 发送] ");
    Serial.println(jsonBuffer);
  }
}