#pragma once

#include <WiFi.h>
#include <PubSubClient.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <DHT.h>
#include <time.h>
#include <esp_system.h>  

// 引脚定义
#define BUTTON_PIN 15    
#define LED1_PIN 19      
#define LED2_PIN 18      
#define DHTPIN 26
#define DHTTYPE DHT22
#define BUZZER_PIN 4   
#define GAS_PIN 34        
#define PIR_PIN 27        

// 阈值定义
const float TEMP_THRESHOLD_C = 20.0;   
const float TEMP_THRESHOLD_F = 68.0;   
const float HUMIDITY_THRESHOLD = 70.0; 
const int GAS_THRESHOLD = 3000;        
const unsigned long MOTION_DELAY = 5000; 

// WiFi & MQTT 配置
const char* ssid = "Wokwi-GUEST";
const char* password = "";
const char* mqtt_server = "broker.hivemq.com";

// MQTT 主题
const char* mqtt_topic_pub = "IoT/Warehouse room1/sensor";     
const char* mqtt_topic_time = "IoT/Warehouse room1/time";      
const char* mqtt_topic_sub = "IoT/Warehouse room1/command";   
const char* mqtt_topic_alarm = "IoT/Warehouse room1/alarm";    
const char* mqtt_topic_lwt = "IoT/Warehouse room1/status";     
const char* mqtt_topic_motion = "IoT/Warehouse room1/motion";  

// 全局对象
WiFiClient espClient;
PubSubClient client(espClient);
DHT dht(DHTPIN, DHTTYPE);
LiquidCrystal_I2C lcd(0x27, 20, 4);

// 状态变量
bool led1State = false;             
bool led2State = false;             
unsigned long lastMsg = 0;           
unsigned long lastDisplayChange = 0;
const long publishInterval = 3000;   
const long displayInterval = 3000;   
int displayState = 0;                
char msg[100];                       
bool welcomeDisplayed = false;
bool isAlarm = false; 
unsigned long alarmStartTime = 0;
const unsigned long ALARM_DURATION = 30000;  
unsigned long lastBuzzerToggle = 0;
const long buzzerInterval = 500;            
uint8_t dot[] = {0x0E, 0x0A, 0x0E, 0x00, 0x00, 0x00, 0x00, 0x00}; 

bool motionDetected = false;         
unsigned long lastMotionTime = 0;    
bool motionStateChanged = false;    

int buttonState;                     
int lastButtonState = HIGH;         
unsigned long lastDebounceTime = 0;  
unsigned long debounceDelay = 50;    
bool restartTriggered = false;       

// WiFi 连接函数（增强重试）
void setup_wifi() {
  Serial.println("Connecting to WiFi...");
  WiFi.begin(ssid, password);
  
  int wifiRetry = 0;
  while (WiFi.status() != WL_CONNECTED && wifiRetry < 10) {
    Serial.print(".");
    delay(500);
    wifiRetry++;
  }
  
  if (WiFi.status() == WL_CONNECTED) {
    Serial.println("\nWiFi connected successfully!");
  } else {
    Serial.println("\nWiFi connection failed after retries! Restarting...");
    esp_restart(); // 重试失败则重启
  }
}

// 读取气体传感器
int readGasLevel() {
  return analogRead(GAS_PIN);
}

// 处理人体红外传感器
void handlePIR() {
  bool currentMotion = digitalRead(PIR_PIN) == HIGH;
  
  if (currentMotion) {
    lastMotionTime = millis();
    if (!motionDetected) {
      motionDetected = true;
      motionStateChanged = true;
      Serial.println("Motion detected!");
      client.publish(mqtt_topic_motion, "detected");
    }
  } else {
    if (motionDetected && (millis() - lastMotionTime > MOTION_DELAY)) {
      motionDetected = false;
      motionStateChanged = true;
      Serial.println("Motion stopped");
      client.publish(mqtt_topic_motion, "stopped");
    }
  }
}

// 初始化系统
void setup() {
  Serial.begin(115200);
  Serial.println("Starting setup()...");

  // 引脚模式设置
  pinMode(BUTTON_PIN, INPUT_PULLUP);
  pinMode(LED1_PIN, OUTPUT);
  pinMode(LED2_PIN, OUTPUT);
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(GAS_PIN, INPUT);
  pinMode(PIR_PIN, INPUT);           
  digitalWrite(LED1_PIN, LOW);
  digitalWrite(LED2_PIN, HIGH);
  digitalWrite(BUZZER_PIN, LOW);
  
  // LCD 初始化
  lcd.init();
  lcd.backlight();
  lcd.createChar(0, dot);
  lcd.clear();
  lcd.print("Initializing...");
  delay(1000);

  // DHT 传感器初始化
  dht.begin();
  
  // WiFi 连接
  setup_wifi();
  
  // MQTT 客户端配置
  client.setServer(mqtt_server, 1883);
  client.setCallback(callback);
  client.setKeepAlive(120);    // 延长心跳间隔
  client.setSocketTimeout(5000); // 延长超时时间

  // 时间同步
  configTime(8 * 3600, 0, "pool.ntp.org");
  struct tm timeinfo;
  int timeRetry = 0;
  while (!getLocalTime(&timeinfo) && timeRetry < 5) {
    Serial.println("Waiting for time sync...");
    delay(1000);
    timeRetry++;
  }
  if (timeRetry < 5) {
    Serial.println("Time synchronized successfully");
    displayWelcome();
    lastDisplayChange = millis();
    lastMsg = 0;
  } else {
    Serial.println("Time sync failed after retries!");
  }

  Serial.println("setup() complete, entering loop()");
}

// 显示欢迎界面
void displayWelcome() { 
  if (!welcomeDisplayed) {
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Hi,Welcome!");
    lcd.setCursor(0, 1);
    lcd.print("Warehouse1,");
    lcd.setCursor(0, 2);
    lcd.print("By Group3!");
    welcomeDisplayed = true;
    delay(2000);
  }
}

// 显示日期时间
void displayDateTime() {
  struct tm timeinfo;
  if (getLocalTime(&timeinfo)) {
    char dtbuf[21];
    strftime(dtbuf, sizeof(dtbuf), "%Y-%m-%d %H:%M:%S", &timeinfo);
    
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("DateTime:");
    lcd.setCursor(0, 1);
    lcd.print(dtbuf);
      
    unsigned long now = millis();
    if (now - lastMsg >= publishInterval) {
      lastMsg = now;
      client.publish(mqtt_topic_time, dtbuf);
    }
  } else {
    lcd.clear();
    lcd.print("Time sync lost!");
  }
}

// 显示传感器数据
void displaySensorData() {
  unsigned long start = millis();
  float h = dht.readHumidity();
  float c = dht.readTemperature();
  float f = dht.readTemperature(true);
  int gas = readGasLevel();
  
  // 超时保护
  if (millis() - start > 1000) {
    lcd.clear();
    lcd.print("Sensor Timeout!");
    return;
  }
  
  // 校验传感器数据
  if (isnan(h) || isnan(c) || isnan(f)) {
    Serial.println(F("Failed to read DHT!"));
    lcd.clear();
    lcd.print("Sensor Error!");
    return;
  }

  // 串口打印
  Serial.printf("Humidity: %.1f%%  Temp: %.1f°C / %.1f°F  Gas: %d  Motion: %s\n", 
               h, c, f, gas, motionDetected ? "Yes" : "No");

  // 报警判断
  bool tempAlarm = c > TEMP_THRESHOLD_C; 
  bool humAlarm = h > HUMIDITY_THRESHOLD;
  bool gasAlarm = gas > GAS_THRESHOLD;
  
  if (tempAlarm || humAlarm || gasAlarm) {
    isAlarm = true;
    alarmStartTime = millis();
    
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("ALARM!");
    lcd.setCursor(0, 1);
    if (tempAlarm) lcd.print("Temp Over!");
    else if (humAlarm) lcd.print("Humidity Over!");
    else if (gasAlarm) lcd.print("Gas Over!");
    
    lcd.setCursor(0, 2);
    lcd.print(tempAlarm ? String(c) + "C > " + String(TEMP_THRESHOLD_C) + "C" 
                       : humAlarm ? String(h) + "% > " + String(HUMIDITY_THRESHOLD) + "%"
                       : String(gas) + " > " + String(GAS_THRESHOLD));
    
    lcd.setCursor(0, 3);
    lcd.print("Motion: ");
    lcd.print(motionDetected ? "Detected" : "None");
    
    // 发布报警消息
    char alarmMsg[100];
    snprintf(alarmMsg, sizeof(alarmMsg), "Alarm: %s %.1f%s",
             tempAlarm ? "Temp" : humAlarm ? "Humidity" : "Gas",
             tempAlarm ? (float)c : humAlarm ? (float)h : (float)gas,
             tempAlarm ? "C" : humAlarm ? "%" : "");
    client.publish(mqtt_topic_alarm, alarmMsg);
  } else {
    isAlarm = false;
    digitalWrite(BUZZER_PIN, LOW);
    
    // 正常显示传感器数据
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Humidity: "); 
    lcd.print(h, 1); 
    lcd.print("%");
    
    lcd.setCursor(0, 1);
    lcd.print("Temperature: ");
    lcd.print(c, 2); 
    lcd.write(0); 
    lcd.print("C");

    lcd.setCursor(0, 2);
    lcd.print("Gas Level: ");
    lcd.print(gas);

    lcd.setCursor(0, 3);
    lcd.print("Motion: ");
    lcd.print(motionDetected ? "Detected" : "None");

    // 发布传感器数据
    if (millis() - lastMsg >= publishInterval) {
      lastMsg = millis();
      snprintf(msg, sizeof(msg), 
               "{\"temp\": %.1f, \"hum\": %.1f, \"gas\": %d, \"motion\": %s}", 
               c, h, gas, motionDetected ? "true" : "false");
      client.publish(mqtt_topic_pub, msg);
    }
  }
}

// MQTT 回调函数
void callback(char* topic, byte* payload, unsigned int length) { 
  payload[length] = 0;
  String command = String((char*)payload);
  command.toUpperCase();  
  Serial.print("Received MQTT: ");
  Serial.println(command);
  
  if (command == "RESTART") {
    Serial.println("MQTT command: Restart");
    blinkAndRestart();  
  }
}

// 蜂鸣器控制
void controlBuzzer(bool enable) { 
  static int buzzerPattern = 0;
  unsigned long now = millis();

  if (enable) {
    if (now - lastBuzzerToggle >= buzzerInterval) {
      lastBuzzerToggle = now;
      buzzerPattern = (buzzerPattern + 1) % 4;

      switch (buzzerPattern) {
        case 0: tone(BUZZER_PIN, 1000); break;
        case 1: tone(BUZZER_PIN, 1500); break;
        case 2: tone(BUZZER_PIN, 2000); break;
        case 3: noTone(BUZZER_PIN); break;
      }
    }
  } else {
    noTone(BUZZER_PIN);
  }
}

// 重启流程
void blinkAndRestart() {
  lcd.clear();
  lcd.print("Restarting...");
  
  for (int i = 0; i < 3; i++) {
    digitalWrite(LED2_PIN, LOW);
    delay(300);
    digitalWrite(LED2_PIN, HIGH);
    delay(300);
  }
  
  client.publish(mqtt_topic_lwt, "restarting", true);
  delay(500);
  esp_restart(); 
}

// 按键处理
void handleButton() {
  int reading = digitalRead(BUTTON_PIN);

  if (reading != lastButtonState) {
    lastDebounceTime = millis();
  }

  if ((millis() - lastDebounceTime) > debounceDelay) {
    if (reading != buttonState) {
      buttonState = reading;

      if (buttonState == LOW && !restartTriggered) {
        restartTriggered = true;
        Serial.println("Button pressed: Restart");
        blinkAndRestart();
      }
    }
  }

  lastButtonState = reading;
}

// MQTT 重连逻辑（优化版）
void reconnect() {
  if (client.connected()) return;

  Serial.println("Connecting to MQTT...");
  // 带遗嘱的连接
  if (client.connect("ESP32ClientDevice", mqtt_topic_lwt, 0, true, "offline")) {
    Serial.println("MQTT connected!");
    client.publish(mqtt_topic_lwt, "online", true);
    client.subscribe(mqtt_topic_sub);
    delay(500); // 等待服务器处理
  } else {
    // 打印失败状态码
    Serial.print("MQTT failed (code=");
    Serial.print(client.state());
    Serial.println("), retry in 5s...");
    delay(5000); // 避免频繁重试
  }
}

// 主循环
void loop() {
  // 优先处理 MQTT 收发
  client.loop();  

  // MQTT 重连逻辑
  if (!client.connected()) {
    reconnect();  
  }
  
  // 按键处理
  handleButton(); 
  // 人体红外处理
  handlePIR();    

  unsigned long now = millis();

  // 报警逻辑
  if (isAlarm) {
    controlBuzzer(true);  
    
    // LED 闪烁
    if (now - lastBuzzerToggle >= buzzerInterval/2) {
      lastBuzzerToggle = now;
      digitalWrite(LED1_PIN, !digitalRead(LED1_PIN)); 
    }
    
    // 报警时长限制
    if (now - alarmStartTime > ALARM_DURATION) {
      isAlarm = false;
      digitalWrite(BUZZER_PIN, LOW);
      digitalWrite(LED1_PIN, led1State);
    }
  }

  // 运动触发显示更新
  if (motionStateChanged && !isAlarm && !restartTriggered) {
    motionStateChanged = false;
    switch (displayState) {
      case 1: displayDateTime(); break;
      case 2: displaySensorData(); break;
    }
  }

  // 自动切换显示
  if (now - lastDisplayChange >= displayInterval && !isAlarm && !restartTriggered) {
    lastDisplayChange = now;
    displayState = (displayState + 1) % 3;
    switch (displayState) {
      case 0: displayWelcome(); break;
      case 1: displayDateTime(); break;
      case 2: displaySensorData(); break;
    }
  }
}