/*
 * SMART HOME SYSTEM - ESP32 + Wokwi + Blynk + RTC + Custom MQ2 Chip
 * Fitur: Fire Alarm, Motion Detector, Auto Light, Climate Control, Smart Lock, Energy Saver
 */

#define BLYNK_TEMPLATE_ID "TMPL6y5_nUYk7"
#define BLYNK_TEMPLATE_NAME "Smart Home"
#define BLYNK_AUTH_TOKEN "2_KhA7WjxP40bNbBc9xzEROQjXIodR0r"

#include <WiFi.h>
#include <BlynkSimpleEsp32.h>
#include <DHT.h>
#include <ESP32Servo.h>
#include <Wire.h>
#include <TimeLib.h>

// WiFi credentials
char ssid[] = "Wokwi-GUEST";
char pass[] = "";

// Pin definitions
#define MQ2_AO_PIN 4             // MQ2 analog output pin (sesuai dengan diagram)
#define MQ2_DO_PIN 5             // MQ2 digital output pin
#define PIR_DOOR_PIN 2           // PIR sensor pintu
#define PIR_ROOM_PIN 18          // PIR sensor ruangan (pindah dari pin 4)
#define DHT_PIN 15               // DHT22 sensor
#define BUZZER_PIN 12            // Buzzer
#define FIRE_LED_PIN 13          // LED fire alarm
#define CAMERA_LED_PIN 14        // LED kamera recording
#define LIGHT_LED_PIN 27         // LED lampu utama
#define FAN_LED_PIN 26           // LED kipas/AC
#define SERVO_PIN 25             // Servo smart lock

// I2C pins for RTC
#define SDA_PIN 21
#define SCL_PIN 22

// DHT sensor
#define DHT_TYPE DHT22
DHT dht(DHT_PIN, DHT_TYPE);

// Servo motor
Servo doorLock;

// RTC DS1307 I2C Address
#define DS1307_I2C_ADDRESS 0x68

// Function to convert decimal to BCD
byte decToBcd(byte val) {
  return ((val/10*16) + (val%10));
}

// Function to convert BCD to decimal
byte bcdToDec(byte val) {
  return ((val/16*10) + (val%16));
}

// Variables
bool fireAlarmActive = false;
bool motionDetected = false;
bool lightAutoMode = true;
bool fanAutoMode = true;
bool lockStatus = false; // false = unlocked, true = locked
unsigned long lastMotionTime = 0;
unsigned long lastFireCheck = 0;
unsigned long lastSensorRead = 0;
float temperature = 0;
float humidity = 0;
int gasLevel = 0;
float gasPPM = 0;
int currentHour = 12;
int currentMinute = 0;
String currentTimeString = "";

// MQ2 Sensor Variables
float gasVoltage = 0;
int gasPercentage = 0;
bool digitalGasDetected = false;

// Virtual pins for Blynk
#define V_FIRE_STATUS V0
#define V_MOTION_STATUS V1
#define V_TEMPERATURE V2
#define V_HUMIDITY V3
#define V_LIGHT_CONTROL V4
#define V_LIGHT_AUTO V5
#define V_FAN_CONTROL V6
#define V_FAN_AUTO V7
#define V_LOCK_CONTROL V8
#define V_LOCK_STATUS V9
#define V_GAS_LEVEL V10
#define V_NOTIFICATIONS V11
#define V_CURRENT_TIME V12

// Timer untuk update data
BlynkTimer timer;

void setup() {
  Serial.begin(115200);
  
  // Test buzzer saat startup
  digitalWrite(BUZZER_PIN, HIGH);
  delay(500);
  digitalWrite(BUZZER_PIN, LOW);
  
  // Initialize I2C
  Wire.begin(SDA_PIN, SCL_PIN);
  
  // Initialize pins
  pinMode(MQ2_AO_PIN, INPUT);
  pinMode(MQ2_DO_PIN, INPUT);
  pinMode(PIR_DOOR_PIN, INPUT);
  pinMode(PIR_ROOM_PIN, INPUT);
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(FIRE_LED_PIN, OUTPUT);
  pinMode(CAMERA_LED_PIN, OUTPUT);
  pinMode(LIGHT_LED_PIN, OUTPUT);
  pinMode(FAN_LED_PIN, OUTPUT);
  
  // Initialize DHT
  dht.begin();
  
  // Initialize Servo
  doorLock.attach(SERVO_PIN);
  doorLock.write(0); // Unlocked position
  
  // Initialize RTC
  Wire.begin(SDA_PIN, SCL_PIN);
  setDS1307time(0, 30, 12, 1, 1, 1, 24); // Set initial time: 12:30:00, Day 1, Date 1, Month 1, Year 2024
  
  // Initialize Blynk
  Blynk.begin(BLYNK_AUTH_TOKEN, ssid, pass);
  
  // Setup timers
  timer.setInterval(1000L, checkSensors);      // Check sensors every 1 second
  timer.setInterval(5000L, updateBlynkData);   // Update Blynk every 5 seconds
  timer.setInterval(1000L, updateTime);        // Update time every second
  timer.setInterval(30000L, checkEnergyMode);  // Check energy saving every 30 seconds
  
  Serial.println("Smart Home System Started!");
  Blynk.virtualWrite(V_NOTIFICATIONS, "Smart Home System Online");
}

void loop() {
  Blynk.run();
  timer.run();
}

// Function to check all sensors
void checkSensors() {
  // Read MQ2 gas sensor
  readMQ2Sensor();
  checkFireAlarm();
  
  // Read motion sensors
  checkMotionSensors();
  
  // Read temperature and humidity
  if (millis() - lastSensorRead > 2000) {
    temperature = dht.readTemperature();
    humidity = dht.readHumidity();
    
    if (isnan(temperature) || isnan(humidity)) {
      temperature = 25.0; // Default value for simulation
      humidity = 60.0;
    }
    
    // Auto fan control based on temperature
    if (fanAutoMode) {
      if (temperature > 28.0) {
        digitalWrite(FAN_LED_PIN, HIGH);
        Blynk.virtualWrite(V_FAN_CONTROL, 1);
      } else if (temperature < 26.0) {
        digitalWrite(FAN_LED_PIN, LOW);
        Blynk.virtualWrite(V_FAN_CONTROL, 0);
      }
    }
    
    lastSensorRead = millis();
  }
  
  // Auto light control based on time
  autoLightControl();
}

// Function to read MQ2 sensor
void readMQ2Sensor() {
  // Read analog value (0-4095 for ESP32)
  gasLevel = analogRead(MQ2_AO_PIN);
  
  // Convert to voltage (0-5V range dari custom chip)
  gasVoltage = (gasLevel * 5.0) / 4095.0;
  
  // Convert to percentage (0-100%)
  gasPercentage = map(gasLevel, 0, 4095, 0, 100);
  
  // Read digital output
  digitalGasDetected = digitalRead(MQ2_DO_PIN);
  
  // Calculate PPM estimation (simplified)
  // Asumsi: 0-5V = 0-1000 PPM untuk simulasi
  gasPPM = (gasVoltage / 5.0) * 1000.0;
  
  // Debug output
  Serial.print("Gas ADC: ");
  Serial.print(gasLevel);
  Serial.print(" | Voltage: ");
  Serial.print(gasVoltage, 2);
  Serial.print("V | Percentage: ");
  Serial.print(gasPercentage);
  Serial.print("% | PPM: ");
  Serial.print(gasPPM, 1);
  Serial.print(" | Digital: ");
  Serial.println(digitalGasDetected ? "HIGH" : "LOW");
}

// Fire alarm system - menggunakan nilai persentase dan digital output
void checkFireAlarm() {
  // Menggunakan kombinasi analog dan digital reading
  // Ambang batas: 60% untuk analog, atau digital output HIGH
  bool fireDetected = (gasPercentage > 60) || digitalGasDetected;
  
  if (fireDetected) {
    if (!fireAlarmActive) {
      fireAlarmActive = true;
      digitalWrite(FIRE_LED_PIN, HIGH);
      tone(BUZZER_PIN, 1000); // Bunyi buzzer 1 kHz
      Blynk.virtualWrite(V_FIRE_STATUS, 1);
      
      String alertMessage = "🔥 FIRE DETECTED! Gas: " + String(gasPercentage) + "% | " + 
                           String(gasPPM, 1) + " PPM | Voltage: " + String(gasVoltage, 2) + "V";
      
      Blynk.logEvent("fire_alarm", alertMessage);
      
      Serial.println("🔥 FIRE ALARM ACTIVATED!");
      Serial.println("Gas Percentage: " + String(gasPercentage) + "%");
      Serial.println("Gas PPM: " + String(gasPPM, 1));
      Serial.println("Digital Output: " + String(digitalGasDetected ? "HIGH" : "LOW"));
    }
  } else {
    if (fireAlarmActive) {
      fireAlarmActive = false;
      digitalWrite(FIRE_LED_PIN, LOW);
      noTone(BUZZER_PIN); // Matikan buzzer
      Blynk.virtualWrite(V_FIRE_STATUS, 0);
      Serial.println("Fire alarm deactivated");
    }
  }
}

// Motion detection system
void checkMotionSensors() {
  // Door motion sensor (Camera simulation)
  if (digitalRead(PIR_DOOR_PIN) == HIGH) {
    if (!motionDetected) {
      motionDetected = true;
      digitalWrite(CAMERA_LED_PIN, HIGH);
      
      Blynk.virtualWrite(V_MOTION_STATUS, 1);
      Blynk.logEvent("motion_detected", "📷 Motion detected at door - Photo taken! Time: " + currentTimeString);
      
      Serial.println("📷 Motion detected - Camera recording at " + currentTimeString);
      
      // Turn off camera LED after 3 seconds
      timer.setTimeout(3000L, []() {
        digitalWrite(CAMERA_LED_PIN, LOW);
        motionDetected = false;
        Blynk.virtualWrite(V_MOTION_STATUS, 0);
      });
    }
  }
  
  // Room motion sensor for energy saving
  if (digitalRead(PIR_ROOM_PIN) == HIGH) {
    lastMotionTime = millis();
  }
}

// Auto light control based on RTC time
void autoLightControl() {
  if (lightAutoMode) {
    // Night: 18:00 - 06:00 (6 PM to 6 AM)
    if (currentHour >= 18 || currentHour < 6) {
      digitalWrite(LIGHT_LED_PIN, HIGH);
      Blynk.virtualWrite(V_LIGHT_CONTROL, 1);
    } else {
      digitalWrite(LIGHT_LED_PIN, LOW);
      Blynk.virtualWrite(V_LIGHT_CONTROL, 0);
    }
  }
}

// Energy saving mode
void checkEnergyMode() {
  if (millis() - lastMotionTime > 120000) { // No motion for 2 minutes
    // Turn off lights and fan to save energy
    if (digitalRead(LIGHT_LED_PIN) == HIGH || digitalRead(FAN_LED_PIN) == HIGH) {
      digitalWrite(LIGHT_LED_PIN, LOW);
      digitalWrite(FAN_LED_PIN, LOW);
      
      Blynk.virtualWrite(V_LIGHT_CONTROL, 0);
      Blynk.virtualWrite(V_FAN_CONTROL, 0);
      Blynk.logEvent("energy_save", "⚡ Energy saving mode activated at " + currentTimeString);
      
      Serial.println("⚡ Energy saving mode activated at " + currentTimeString);
    }
  }
}

// Update data to Blynk
void updateBlynkData() {
  Blynk.virtualWrite(V_TEMPERATURE, temperature);
  Blynk.virtualWrite(V_HUMIDITY, humidity);
  Blynk.virtualWrite(V_GAS_LEVEL, gasPercentage); // Mengirim persentase gas
  Blynk.virtualWrite(V_CURRENT_TIME, currentTimeString);
  
  // Update lock status
  Blynk.virtualWrite(V_LOCK_STATUS, lockStatus ? "🔒 Locked" : "🔓 Unlocked");
}

// Update time from RTC
void updateTime() {
  readDS1307time(&currentHour, &currentMinute);
  
  // Format time string
  String hourStr = currentHour < 10 ? "0" + String(currentHour) : String(currentHour);
  String minuteStr = currentMinute < 10 ? "0" + String(currentMinute) : String(currentMinute);
  
  currentTimeString = hourStr + ":" + minuteStr;
  
  Serial.println("Current time: " + currentTimeString);
}

// Function to set DS1307 time
void setDS1307time(byte second, byte minute, byte hour, byte dayOfWeek, byte dayOfMonth, byte month, byte year) {
  Wire.beginTransmission(DS1307_I2C_ADDRESS);
  Wire.write(0); // set next input to start at the seconds register
  Wire.write(decToBcd(second)); // set seconds
  Wire.write(decToBcd(minute)); // set minutes
  Wire.write(decToBcd(hour)); // set hours
  Wire.write(decToBcd(dayOfWeek)); // set day of week (1=Sunday, 7=Saturday)
  Wire.write(decToBcd(dayOfMonth)); // set date (1 to 31)
  Wire.write(decToBcd(month)); // set month
  Wire.write(decToBcd(year)); // set year (0 to 99)
  Wire.endTransmission();
}

// Function to read DS1307 time
void readDS1307time(int* hour, int* minute) {
  Wire.beginTransmission(DS1307_I2C_ADDRESS);
  Wire.write(0); // set DS1307 register pointer to 00h
  Wire.endTransmission();
  Wire.requestFrom(DS1307_I2C_ADDRESS, 7);
  
  byte second = bcdToDec(Wire.read() & 0x7f);
  *minute = bcdToDec(Wire.read());
  *hour = bcdToDec(Wire.read() & 0x3f);
  byte dayOfWeek = bcdToDec(Wire.read());
  byte dayOfMonth = bcdToDec(Wire.read());
  byte month = bcdToDec(Wire.read());
  byte year = bcdToDec(Wire.read());
}

// Blynk Virtual Pin Handlers

// Light manual control
BLYNK_WRITE(V_LIGHT_CONTROL) {
  if (!lightAutoMode) {
    int value = param.asInt();
    digitalWrite(LIGHT_LED_PIN, value);
    Serial.println("Light " + String(value ? "ON" : "OFF") + " at " + currentTimeString);
  }
}

// Light auto mode toggle
BLYNK_WRITE(V_LIGHT_AUTO) {
  lightAutoMode = param.asInt();
  Serial.println("Light auto mode: " + String(lightAutoMode ? "ON" : "OFF"));
}

// Fan manual control
BLYNK_WRITE(V_FAN_CONTROL) {
  if (!fanAutoMode) {
    int value = param.asInt();
    digitalWrite(FAN_LED_PIN, value);
    Serial.println("Fan " + String(value ? "ON" : "OFF") + " at " + currentTimeString);
  }
}

// Fan auto mode toggle
BLYNK_WRITE(V_FAN_AUTO) {
  fanAutoMode = param.asInt();
  Serial.println("Fan auto mode: " + String(fanAutoMode ? "ON" : "OFF"));
}

// Smart lock control
BLYNK_WRITE(V_LOCK_CONTROL) {
  int value = param.asInt();
  lockStatus = value;
  
  if (lockStatus) {
    doorLock.write(90); // Locked position
    Blynk.logEvent("door_locked", "🔒 Door locked at " + currentTimeString);
    Serial.println("🔒 Door LOCKED at " + currentTimeString);
  } else {
    doorLock.write(0); // Unlocked position
    Blynk.logEvent("door_unlocked", "🔓 Door unlocked at " + currentTimeString);
    Serial.println("🔓 Door UNLOCKED at " + currentTimeString);
  }
}

// Connected to Blynk
BLYNK_CONNECTED() {
  Serial.println("Connected to Blynk!");
  Blynk.syncAll(); // Sync all virtual pins
}