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

const int sendingPins[5] = {2, 3, 4, 5, 6}; // Pins for sending signals
const int receivingPins[5] = {8, 9, 10, 11, 12}; // Pins for receiving signals
const int buttonPin = A0; // Button pin
const int redLedPin = 7; // Red LED pin
const int greenLedPin = 13; // Green LED pin

bool buttonPressed = false; // Flag to track if the button is pressed
bool pinsReceived[5] = {false}; // Array to mark received pins

// Set the LCD address to 0x27 for a 16 chars and 2 line display
LiquidCrystal_I2C lcd(0x27, 20, 4);

void setup() {
  Serial.begin(115200);

  // Initialize the LCD
  lcd.init();

  // Turn on the backlight
  lcd.backlight();

  // Set sending pins as OUTPUT
  for (int i = 0; i < 5; i++) {
    pinMode(sendingPins[i], OUTPUT);
  }

  // Set receiving pins as INPUT_PULLUP
  for (int i = 0; i < 5; i++) {
    pinMode(receivingPins[i], INPUT_PULLUP);
  }

  // Set button pin as INPUT_PULLUP
  pinMode(buttonPin, INPUT_PULLUP);

  // Set LED pins as OUTPUT
  pinMode(redLedPin, OUTPUT);
  pinMode(greenLedPin, OUTPUT);

  // Display the initial message on the LCD
  lcd.setCursor(0, 0);
  lcd.print("Press the button");
}

void loop() {
  // Check if button A0 is pressed
  if (digitalRead(buttonPin) == LOW && !buttonPressed) {
    // Set the flag to indicate that the button has been pressed
    buttonPressed = true;

    int numReceived = 0; // Counter for received pins

    // Loop through each sending pin
    for (int i = 0; i < 5; i++) {
      // Send signal from the current sending pin
      digitalWrite(sendingPins[i], LOW);

      // Loop through each receiving pin and check its value
      for (int j = 0; j < 5; j++) {
        // Read the value of the receiving pin
        int receivedValue = digitalRead(receivingPins[j]);

        // If the pin receives the signal (LOW), mark it as received
        if (receivedValue == LOW) {
          pinsReceived[j] = true;
          numReceived++; // Increment the counter for received pins
        }
      }

      // Turn off signal on the current sending pin
      digitalWrite(sendingPins[i], HIGH);

      // Delay for a short duration before the next iteration
      delay(100); // Adjust delay duration as needed
    }

    // Check if all pins are received
    bool allReceived = true;
    for (int i = 0; i < 5; i++) {
      if (!pinsReceived[i]) {
        allReceived = false;
        break;
      }
    }

    // Display the result on LCD
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Received: ");
    lcd.print(numReceived);
    lcd.setCursor(0, 1);

    // Control LEDs based on the connection status
    if (allReceived) {
      digitalWrite(greenLedPin, HIGH); // Turn on green LED
      digitalWrite(redLedPin, LOW); // Turn off red LED
      lcd.print("Connection OK");
    } else {
      digitalWrite(greenLedPin, LOW); // Turn off green LED
      digitalWrite(redLedPin, HIGH); // Turn on red LED
      lcd.print("M: ");
      for (int i = 0; i < 5; i++) {
        if (!pinsReceived[i]) {
          // Display pin number as 1 to 5 instead of 8 to 12
          lcd.print(5 - i);
          lcd.print(" ");
        }
      }
    }

    // Reset pinsReceived array and button press flag for next button press
    for (int i = 0; i < 5; i++) {
      pinsReceived[i] = false;
    }

    // Reset the button press flag when the button is released
    buttonPressed = false;
  }
}