#include <WiFi.h>
#include <HTTPClient.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>

/* ========== WIFI SETTINGS ========== */
const char* ssid = "Wokwi-GUEST";
const char* password = "";

/* ========== THINGSPEAK SETTINGS ========== */
String apiKey = "5HD7ORL7KQ025ASW";
const char* server = "http://api.thingspeak.com/update";

/* ========== SENSOR PINS ========== */
#define CURRENT_PIN 34   // ACS712
#define VOLTAGE_PIN 35   // ZMPT101B

/* ========== CALIBRATION VALUES ========== */
float currentSensitivity = 0.185; // ACS712 5A = 185mV/A
float voltageCalibration = 250.0; // Max 250V (simulation)

/* ========== THRESHOLD VALUES ========== */
float currentThresholdLow = 0.5; // Low current threshold (in Amps)
float currentThresholdHigh = 5.0; // High current threshold (in Amps)
float voltageThresholdLow = 100.0; // Low voltage threshold (in Volts)
float voltageThresholdHigh = 240.0; // High voltage threshold (in Volts)

/* ========== LCD SETTINGS ========== */
LiquidCrystal_I2C lcd(0x27, 16, 2); // Change the address and size if necessary

void setup() {
  Serial.begin(115200);
  
  // Initialize LCD
  lcd.begin(16, 2); 
  lcd.print("Initializing...");
  delay(2000);
  
  // Connect to WiFi
  WiFi.begin(ssid, password);
  Serial.print("Connecting WiFi");
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nWiFi Connected");

  // Display WiFi status on LCD
  lcd.clear();
  lcd.print("WiFi Connected");
  delay(2000);
}

void loop() {
  /* ========== CURRENT SENSOR ========== */
  int rawCurrent = analogRead(CURRENT_PIN);
  float voltageCurrent = (rawCurrent / 4095.0) * 3.3;
  float current = (voltageCurrent - 1.65) / currentSensitivity;
  if (current < 0) current = 0;

  /* ========== VOLTAGE SENSOR ========== */
  int rawVoltage = analogRead(VOLTAGE_PIN);
  float voltage = (rawVoltage / 4095.0) * voltageCalibration;

  // Threshold Check for Current
  if (current < currentThresholdLow) {
    Serial.println("Warning: Current below threshold!");
  } else if (current > currentThresholdHigh) {
    Serial.println("Warning: Current exceeds threshold!");
  }

  // Threshold Check for Voltage
  if (voltage < voltageThresholdLow) {
    Serial.println("Warning: Voltage below threshold!");
  } else if (voltage > voltageThresholdHigh) {
    Serial.println("Warning: Voltage exceeds threshold!");
  }

  // Display readings on Serial Monitor
  Serial.print("Voltage: ");
  Serial.print(voltage);
  Serial.print(" V | Current: ");
  Serial.print(current);
  Serial.println(" A");

  // Display readings on LCD
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("V: " + String(voltage) + "V");
  lcd.setCursor(0, 1);
  lcd.print("I: " + String(current) + "A");
  delay(2000); // Update every 2 seconds

  /* ========== SEND TO THINGSPEAK ========== */
  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;

    String url = server;
    url += "?api_key=" + apiKey;
    url += "&field1=" + String(voltage);
    url += "&field2=" + String(current);

    http.begin(url);
    int httpCode = http.GET();
    http.end();

    Serial.print("ThingSpeak Response: ");
    Serial.println(httpCode);
  }

  delay(15000); // ThingSpeak minimum 15 seconds
}