#include <U8g2lib.h>  // Include the U8g2 library

U8G2_SSD1306_128X64_NONAME_F_HW_I2C u8g2(U8G2_R0);  // Define the OLED object

const int symbol1 = 68;  // Symbol for the first display (e.g., arrow)
const int symbol2 = 78;  // Symbol for the second display (e.g., cross)

const int microphonePin = A0;  // Analog pin connected to the microphone
const int relayPin = 2;       // Digital pin connected to the relay

const int peakThreshold = 500;  // Adjust this threshold according to your microphone sensitivity
const int peakCount = 3;        // Number of peaks to detect

int del = 3000; 
bool lock_flag = false;

int peakDetected = 0;  // Counter for the number of peaks detected

void setup() {
  u8g2.begin();                       // Initialize the OLED display
  u8g2.setFont(u8g2_font_profont12_tr);  // Choose a font for symbols
  u8g2.clearBuffer();                  // Clear the display buffer
  pinMode(relayPin, OUTPUT);    // Set relay pin as an output
  digitalWrite(relayPin, LOW);  // Initially turn off the relay
  Serial.begin(9600);           // Initialize serial communication for debugging
}

void loop() 
{
  int audioValue = analogRead(microphonePin);  // Read the audio input
  Serial.print("Audio Value: ");
  Serial.println(audioValue);
  if (audioValue > peakThreshold) 
  {  // Peak detected
    peakDetected++;  // Increment the peak counter

    if (peakDetected >= peakCount) 
    {
      lock_flag = !lock_flag; // toggle flag
      if(lock_flag)
      {
        Serial.println("Lock");
        digitalWrite(relayPin, HIGH);  // Turn on the relay
        u8g2.clearBuffer();             // Clear the display buffer
        // Show the first symbol
        u8g2.drawGlyph(64, 32, symbol1);  // Display the first symbol
        u8g2.sendBuffer();              // Send the buffer to the OLED display
        peakDetected = 0;              // Reset the peak counter
      }
      else
      {
        Serial.println("Unlock");
        u8g2.clearBuffer();             // Clear the display buffer
        u8g2.drawGlyph(64, 32, symbol2);  // Display the second symbol
        u8g2.sendBuffer();              // Send the buffer to the OLED display
        digitalWrite(relayPin, LOW);   // Turn off the relay
        peakDetected = 0;              // Reset the peak counter
      }
    }
  delay(del);
  }
}