#include <Wire.h>
#include <Adafruit_SSD1306.h>
#include <Adafruit_GFX.h>
#include "EmonLib.h"  // Energy monitoring library

// Pin Definitions
#define VOLTAGE_SENSOR_PIN 34  // ZMPT101B Voltage Sensor
#define CURRENT_SENSOR_PIN 35  // ACS712 Current Sensor
#define BUZZER_PIN 23         
#define LED_PIN 22            

// OLED Display Setup
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

// Energy Monitoring Object
EnergyMonitor emon1;

// Energy Usage Thresholds
const float OVERLOAD_THRESHOLD = 5000.0;  // Power limit for alerts

void setup() {
    Serial.begin(115200);
    
    pinMode(BUZZER_PIN, OUTPUT);
    pinMode(LED_PIN, OUTPUT);
    
    // ✅ Initialize OLED Display
    if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
        Serial.println("❌ OLED Display Failed!");
        while (1);
    }
    
    display.clearDisplay();
    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(10, 10);
    display.print("Smart Energy Meter");
    display.display();
    delay(2000);

    // ✅ Initialize Energy Sensors
    emon1.voltage(VOLTAGE_SENSOR_PIN, 234.0, 1.7);  
    emon1.current(CURRENT_SENSOR_PIN, 30.0);        
}

void loop() {
    // ✅ Read Sensor Data
    emon1.calcVI(20, 2000);
    float voltage = emon1.Vrms;
    float current = emon1.Irms;
    float power = voltage * current;

    // ✅ Display Data on OLED
    display_data(voltage, current, power);

    // ✅ Log Data for Debugging in Wokwi (Since No MQTT)
    log_energy_data(voltage, current, power);

    // ✅ Alert on Overload
    if (power > OVERLOAD_THRESHOLD) {
        trigger_alert();
    } else {
        reset_alert();
    }
    
    delay(5000);  // Update every 5 seconds
}

// ✅ Display Energy Data on OLED
void display_data(float voltage, float current, float power) {
    display.clearDisplay();
    display.setCursor(0, 0);
    display.print("Voltage: "); display.print(voltage); display.print("V");
    display.setCursor(0, 15);
    display.print("Current: "); display.print(current); display.print("A");
    display.setCursor(0, 30);
    display.print("Power: "); display.print(power); display.print("W");
    display.display();
}

// ✅ Log Energy Data to Serial Monitor (For Wokwi)
void log_energy_data(float voltage, float current, float power) {
    Serial.print("Voltage: "); Serial.print(voltage); Serial.print("V, ");
    Serial.print("Current: "); Serial.print(current); Serial.print("A, ");
    Serial.print("Power: "); Serial.print(power); Serial.println("W");
}

// ✅ Trigger Alert if Power Exceeds Safe Limits
void trigger_alert() {
    digitalWrite(LED_PIN, HIGH);
    digitalWrite(BUZZER_PIN, HIGH);
    Serial.println("⚠️ Overload! Power Cutoff Alert!");
    delay(3000);
    digitalWrite(BUZZER_PIN, LOW);
}

// ✅ Reset Alert when Power is Normal
void reset_alert() {
    digitalWrite(LED_PIN, LOW);
}