#include <DHT.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>

// ================== CẤU HÌNH CHÂN ==================
#define DHTPIN 13
#define DHTTYPE DHT22
#define SDA_PIN 12 
#define SCL_PIN 14 

#define PIR_PIN 27
#define DUST_PIN 36        

#define LED_PIR 0
#define LED_HEATER 25
#define LED_FAN 33
#define LED_AC 32
#define LED_HUMIDIFIER 26  

#define RGB_RED 15
#define RGB_GREEN 2
#define RGB_BLUE 4

#define SW_MODE 35         
#define BTN_AC 19          
#define BTN_FAN 23      
#define BTN_HEATER 22      


DHT dht(DHTPIN, DHTTYPE);
LiquidCrystal_I2C lcd(0x27, 16, 2);

float tempRoom = 0;
float humidity = 0;
bool heaterOn = false;
bool acOn = false;
bool humidifierOn = false;
int fanLevel = 0; // 0, 1, 2, 3
bool lastAutoMode = true;

int dustLevel = 0;     
String dustStatus = ""; 

void setup() {
  Serial.begin(115200);
  Wire.begin(SDA_PIN, SCL_PIN);
  
  dht.begin();
  lcd.init();
  lcd.backlight();
  
  pinMode(PIR_PIN, INPUT);
  pinMode(DUST_PIN, INPUT);
  pinMode(SW_MODE, INPUT); 
  pinMode(BTN_AC, INPUT_PULLUP);
  pinMode(BTN_FAN, INPUT_PULLUP);
  pinMode(BTN_HEATER, INPUT_PULLUP);
  
  pinMode(LED_PIR, OUTPUT);
  pinMode(LED_HEATER, OUTPUT);
  pinMode(LED_FAN, OUTPUT);
  pinMode(LED_AC, OUTPUT);
  pinMode(LED_HUMIDIFIER, OUTPUT);
  
  pinMode(RGB_RED, OUTPUT);
  pinMode(RGB_GREEN, OUTPUT);
  pinMode(RGB_BLUE, OUTPUT);

  lcd.setCursor(0, 0);
  lcd.print("HE THONG SMART");
  lcd.setCursor(0, 1);
  lcd.print("HOME READY");
  delay(2000);
  lcd.clear();

  tempRoom = dht.readTemperature();
  humidity = dht.readHumidity();
  Serial.println("Log: He thong khoi dong thanh cong.");
}

void loop() {
  handleDustSensor();
  handlePIRLight();
  handleSmartHome();
}


void handleDustSensor() {
  dustLevel = analogRead(DUST_PIN);
  
  if (dustLevel < 1800) {
    dustStatus = "TOT";
    digitalWrite(RGB_RED, HIGH);
    digitalWrite(RGB_GREEN, HIGH);
    digitalWrite(RGB_BLUE, HIGH);
    Serial.print("Bui: TOT - TRANG (");
  } 
  else if (dustLevel < 2000) {
    dustStatus = "TB";
    digitalWrite(RGB_RED, LOW);
    digitalWrite(RGB_GREEN, HIGH);
    digitalWrite(RGB_BLUE, LOW);
    Serial.print("Bui: TRUNG BINH - XANH LA (");
  } 
  else if (dustLevel < 2100) {
    dustStatus = "KEM";
    digitalWrite(RGB_RED, HIGH);
    digitalWrite(RGB_GREEN, HIGH);
    digitalWrite(RGB_BLUE, LOW);
    Serial.print("Bui: KEM - VANG (");
  } 
  else {
    dustStatus = "XAU";
    digitalWrite(RGB_RED, HIGH);
    digitalWrite(RGB_GREEN, LOW);
    digitalWrite(RGB_BLUE, LOW);
    Serial.print("Bui: XAU - DO (");
  }
  Serial.print(dustLevel);
  Serial.println(")");
}


void handlePIRLight() {
  bool hasMotion = digitalRead(PIR_PIN);

  digitalWrite(LED_PIR, hasMotion ? HIGH : LOW);
  
  static bool lastMotion = false;
  if (hasMotion != lastMotion) {
    Serial.print("PIR: Den ");
    Serial.println(hasMotion ? "ON" : "OFF");
    lastMotion = hasMotion;
  }
}

void handleSmartHome() {
  bool autoMode = digitalRead(SW_MODE);

  if (lastAutoMode && !autoMode) {
    heaterOn = false; 
    acOn = false; 
    fanLevel = 0;
    Serial.println("Mode: MANUAL - Temp Control Reset (Humidifier stays AUTO)");
  }
  lastAutoMode = autoMode;

  float t = dht.readTemperature();
  float h = dht.readHumidity();
  
  if (!isnan(t)) {
    if (t > 100) {
      Serial.println("!!! CANH BAO CHAY: NHIET DO > 100 !!!");
      heaterOn = false; acOn = false;
    }
    if (heaterOn) tempRoom += 0.05;
    if (acOn) tempRoom -= 0.05;
    if (abs(t - tempRoom) > 1.0) tempRoom = t; 
  }
  
  if (!isnan(h)) {
    humidity = h;
  }

  // --- ĐIỀU KHIỂN MÁY TẠO ẨM (Luôn tự động) ---
  // Bật khi độ ẩm < 40% HOẶC bụi ở mức KÉM/XẤU (>= 2000)
  humidifierOn = (humidity < 40) || (dustLevel >= 2000);
  
  // --- XỬ LÝ AUTO/MANUAL CHO NHIỆT ĐỘ ---
  if (autoMode) {
    // Điều khiển nhiệt độ
    if (tempRoom >= 28) {
      acOn = true; heaterOn = false;
    } else if (tempRoom <= 18) {
      heaterOn = true; acOn = false;
    } else if (tempRoom >= 20 && tempRoom <= 22) {
      acOn = false; heaterOn = false;
    }
    
    // Điều khiển quạt
    fanLevel = (tempRoom > 25) ? 1 : 0;
    
  } else {
    handleManualButtons();
  }

  digitalWrite(LED_HEATER, heaterOn);
  digitalWrite(LED_AC, acOn);
  digitalWrite(LED_FAN, fanLevel > 0);
  digitalWrite(LED_HUMIDIFIER, humidifierOn);

  lcd.setCursor(0, 0);
  lcd.print(autoMode ? "AUTO" : "MAN ");
  lcd.print(" T:"); 
  lcd.print(tempRoom, 1); 
  lcd.print(" H:");
  lcd.print((int)humidity);
  lcd.print("  ");

  lcd.setCursor(0, 1);
  lcd.print(dustStatus);
  if (dustStatus == "TB") {
    lcd.print("  ");
  } else if (dustStatus == "KEM") {
    lcd.print(" ");
  } else {
    lcd.print("   ");
  }
  
  lcd.print(heaterOn ? "H" : " ");
  lcd.print(acOn ? "A" : " ");
  lcd.print(humidifierOn ? "M" : " ");
  lcd.print(" F:");
  lcd.print(fanLevel);
  lcd.print("  ");

  delay(200);
}

void handleManualButtons() {
  static unsigned long lastPress = 0;
  if (millis() - lastPress < 250) return;

  if (digitalRead(BTN_AC) == LOW) {
    acOn = !acOn;
    if (acOn) heaterOn = false;
    lastPress = millis();
    Serial.println("Manual: Toggle AC");
  }

  if (digitalRead(BTN_FAN) == LOW) {
    fanLevel++;
    if (fanLevel > 3) fanLevel = 0;
    lastPress = millis();
    Serial.print("Manual: Fan Level "); Serial.println(fanLevel);
  }

  if (digitalRead(BTN_HEATER) == LOW) {
    heaterOn = !heaterOn;
    if (heaterOn) acOn = false;
    lastPress = millis();
    Serial.println("Manual: Toggle Heater");
  }
}