/*
 * Simple EMF Meter for ESP32
 * OpenParanormal Project
 *
 * Lights up LEDs based on electromagnetic field strength
 * Similar to commercial K2 meters
 *
 * Hardware:
 * - ESP32 DevKit
 * - 5x LEDs (Green, Yellow, Orange, Red, Red)
 * - 5x 220Ω resistors
 * - Hall effect sensor (A3144) or coil antenna
 *
 * Wiring:
 * LED 1 (Green)  → GPIO 13 → 220Ω → GND
 * LED 2 (Yellow) → GPIO 12 → 220Ω → GND
 * LED 3 (Orange) → GPIO 14 → 220Ω → GND
 * LED 4 (Red)    → GPIO 27 → 220Ω → GND
 * LED 5 (Red)    → GPIO 26 → 220Ω → GND
 *
 * Hall Sensor:
 * VCC → 3.3V
 * GND → GND
 * OUT → GPIO 34
 */

// LED pins
#define LED1 13  // Green - Low
#define LED2 12  // Yellow - Medium-Low
#define LED3 14  // Orange - Medium
#define LED4 27  // Red - High
#define LED5 26  // Red - Very High

// Sensor pin (analog)
#define SENSOR_PIN 34

// Thresholds for LED activation
#define THRESHOLD1 100
#define THRESHOLD2 200
#define THRESHOLD3 400
#define THRESHOLD4 800
#define THRESHOLD5 1500

// Smoothing
#define SAMPLES 10
int readings[SAMPLES];
int readIndex = 0;
int total = 0;

void setup() {
  Serial.begin(115200);
  Serial.println("OpenParanormal EMF Meter");

  // Set LED pins as outputs
  pinMode(LED1, OUTPUT);
  pinMode(LED2, OUTPUT);
  pinMode(LED3, OUTPUT);
  pinMode(LED4, OUTPUT);
  pinMode(LED5, OUTPUT);

  // Initialize sensor pin
  pinMode(SENSOR_PIN, INPUT);

  // Initialize readings array
  for (int i = 0; i < SAMPLES; i++) {
    readings[i] = 0;
  }

  // Startup animation
  startupAnimation();
}

void loop() {
  // Read sensor with smoothing
  int rawValue = analogRead(SENSOR_PIN);

  // Subtract oldest reading
  total = total - readings[readIndex];
  // Read new value
  readings[readIndex] = rawValue;
  // Add to total
  total = total + readings[readIndex];
  // Advance to next position
  readIndex = (readIndex + 1) % SAMPLES;

  // Calculate average
  int emfValue = total / SAMPLES;

  // Debug output
  Serial.print("EMF Value: ");
  Serial.println(emfValue);

  // Light up LEDs based on thresholds
  if (emfValue >= THRESHOLD1) {
    digitalWrite(LED1, HIGH);
  } else {
    digitalWrite(LED1, LOW);
  }

  if (emfValue >= THRESHOLD2) {
    digitalWrite(LED2, HIGH);
  } else {
    digitalWrite(LED2, LOW);
  }

  if (emfValue >= THRESHOLD3) {
    digitalWrite(LED3, HIGH);
  } else {
    digitalWrite(LED3, LOW);
  }

  if (emfValue >= THRESHOLD4) {
    digitalWrite(LED4, HIGH);
  } else {
    digitalWrite(LED4, LOW);
  }

  if (emfValue >= THRESHOLD5) {
    digitalWrite(LED5, HIGH);
  } else {
    digitalWrite(LED5, LOW);
  }

  delay(100);  // Small delay for stability
}

void startupAnimation() {
  // Light up LEDs in sequence
  for (int i = 0; i < 3; i++) {
    digitalWrite(LED1, HIGH);
    delay(100);
    digitalWrite(LED2, HIGH);
    delay(100);
    digitalWrite(LED3, HIGH);
    delay(100);
    digitalWrite(LED4, HIGH);
    delay(100);
    digitalWrite(LED5, HIGH);
    delay(200);

    // Turn all off
    digitalWrite(LED1, LOW);
    digitalWrite(LED2, LOW);
    digitalWrite(LED3, LOW);
    digitalWrite(LED4, LOW);
    digitalWrite(LED5, LOW);
    delay(200);
  }
}