#include <WiFi.h>
#include <HTTPClient.h>

// ----- Energy Monitoring Sensors -----
#define VOLTAGE_PIN 34      // Analog pin for voltage sensor (ZMPT101B or similar)
#define CURRENT_PIN 35      // Analog pin for current sensor (ACS712 or SCT-013)
#define GAS_PIN 32          // Analog pin for gas sensor (MQ-2, MQ-5, or similar)

// ----- Device Control (Relays/LEDs) -----
#define DEVICE_1_PIN 12     // Main load control
#define DEVICE_2_PIN 27     // Secondary load control
bool device1State = false;
bool device2State = false;

// ----- Energy Calculation Variables -----
float voltage = 0.0;
float current = 0.0;
float power = 0.0;
float energyToday = 0.0;
float gasLevel = 0.0;
unsigned long lastEnergyUpdate = 0;
unsigned long lastReading = 0;

// ----- Calibration Constants -----
const float VOLTAGE_CALIBRATION = 220.0 / 3.3;  // Adjust based on your voltage divider
const float CURRENT_CALIBRATION = 30.0 / 3.3;   // Adjust based on your current sensor (ACS712-30A)
const float VOLTAGE_OFFSET = 1.65;              // ADC offset for AC measurements
const float CURRENT_OFFSET = 1.65;              // ADC offset for AC measurements

// ----- WiFi & Firebase -----
#define FIREBASE_HOST "eya-sesame-default-rtdb.europe-west1.firebasedatabase.app"
// ⚠️ IMPORTANT: Replace with your Firebase Database Secret (NOT API Key!)
// Get it from: Firebase Console → Project Settings → Service Accounts → Database Secrets
#define FIREBASE_AUTH "AIzaSyAN5EQyDzE1G1jDNNq2neQJEnJEzLi9p8Q"  // ← REPLACE THIS!
#define WIFI_SSID "Wokwi-GUEST"
#define WIFI_PASSWORD ""

// ----- Setup -----
void setup() {
  Serial.begin(115200);

  // Setup device control pins
  pinMode(DEVICE_1_PIN, OUTPUT);
  pinMode(DEVICE_2_PIN, OUTPUT);
  digitalWrite(DEVICE_1_PIN, LOW);
  digitalWrite(DEVICE_2_PIN, LOW);

  // Setup analog input pins
  pinMode(VOLTAGE_PIN, INPUT);
  pinMode(CURRENT_PIN, INPUT);
  pinMode(GAS_PIN, INPUT);

  // Connect to WiFi
  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
  Serial.print("Connecting to WiFi");
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nConnected to WiFi!");
  Serial.println("Energy Monitoring System Started");

  lastEnergyUpdate = millis();
  lastReading = millis();
}

// ----- Loop -----
void loop() {
  // Read device states from Firebase
  readDeviceStates();

  // Read and send energy data every 2 seconds
  if (millis() - lastReading >= 2000) {
    readAndSendEnergyData();
    lastReading = millis();
  }

  // Update daily energy accumulation
  updateEnergyAccumulation();

  delay(100);  // Small delay to prevent overwhelming the system
}

// ----- Read Device States from Firebase -----
void readDeviceStates() {
  HTTPClient http;
  String url = String("https://") + FIREBASE_HOST + "/.json?auth=" + FIREBASE_AUTH;
  http.begin(url);

  int code = http.GET();
  if (code == 200) {
    String payload = http.getString();

    // Parse device states
    device1State = payload.indexOf("\"Device_1\":true") != -1;
    digitalWrite(DEVICE_1_PIN, device1State);

    device2State = payload.indexOf("\"Device_2\":true") != -1;
    digitalWrite(DEVICE_2_PIN, device2State);

    Serial.println("Device 1: " + String(device1State ? "ON" : "OFF") +
                   " | Device 2: " + String(device2State ? "ON" : "OFF"));
  }

  http.end();
}

// ----- Read and Send Energy Data -----
void readAndSendEnergyData() {
  // Read voltage sensor (simulated with potentiometer in Wokwi)
  int voltageRaw = analogRead(VOLTAGE_PIN);
  float voltageReading = voltageRaw * (3.3 / 4095.0);

  // For simulation: map 0-3.3V to 200-240V range
  // In real hardware, use proper voltage sensor calibration
  voltage = 200.0 + (voltageReading / 3.3) * 40.0;

  // Read current sensor (simulated with potentiometer in Wokwi)
  int currentRaw = analogRead(CURRENT_PIN);
  float currentReading = currentRaw * (3.3 / 4095.0);

  // For simulation: map 0-3.3V to 0-15A range
  // In real hardware, use proper current sensor calibration (ACS712, SCT-013)
  current = (currentReading / 3.3) * 15.0;

  // Calculate power (P = V × I)
  power = voltage * current;

  // Read gas sensor (simulated with potentiometer in Wokwi)
  int gasRaw = analogRead(GAS_PIN);
  gasLevel = gasRaw * (3.3 / 4095.0);  // Convert to voltage (0-3.3V)

  // In real hardware with MQ-2/MQ-5:
  // - gasLevel represents analog voltage output
  // - Higher voltage = higher gas concentration
  // - Typical range: 0-3.3V or 0-5V depending on sensor

  // Print readings
  Serial.println("=== Energy Readings ===");
  Serial.println("Voltage: " + String(voltage, 1) + " V");
  Serial.println("Current: " + String(current, 2) + " A");
  Serial.println("Power: " + String(power, 1) + " W");
  Serial.println("Energy Today: " + String(energyToday, 3) + " kWh");
  Serial.println("Gas Level: " + String(gasLevel, 2) + " V");

  // Send to Firebase
  Serial.println("📤 Sending to Firebase...");
  sendValue("/Voltage", voltage);
  sendValue("/Current", current);
  sendValue("/Power", power);
  sendValue("/EnergyToday", energyToday);
  sendValue("/Gas", gasLevel);
  Serial.println("✅ All values sent!");
}

// ----- Update Energy Accumulation -----
void updateEnergyAccumulation() {
  // Calculate energy consumed since last update
  // Energy (kWh) = Power (W) × Time (hours) / 1000
  unsigned long currentTime = millis();
  unsigned long timeDiff = currentTime - lastEnergyUpdate;

  if (timeDiff >= 1000) {  // Update every second
    float hours = timeDiff / 3600000.0;  // Convert ms to hours
    float energyIncrement = (power * hours) / 1000.0;  // Convert W to kW
    energyToday += energyIncrement;

    lastEnergyUpdate = currentTime;
  }
}

// ----- Send a value to Firebase -----
void sendValue(String path, float value) {
  HTTPClient http;
  String url = String("https://") + FIREBASE_HOST + path + ".json?auth=" + FIREBASE_AUTH;
  http.begin(url);
  http.addHeader("Content-Type", "application/json");
  String json = String(value);
  int httpCode = http.PUT(json);

  // Debug: Print HTTP response code
  if (httpCode != 200) {
    Serial.println("❌ Firebase Error on " + path + ": HTTP " + String(httpCode));
  }

  http.end();
}