#include <LiquidCrystal_I2C.h> // Include the LiquidCrystal_I2C library if not already done

const int startButtonPin = 9; // New pin number for the start button
const int endButtonPin = 8;   // New pin number for the end button

const int numPins = 6;        // Number of pins being tested
const int outputPins[numPins] = {7, 6, 5, 4, 3, 2}; // Output pin numbers (7-2)
const int inputPins[numPins] = {14, 15, 16, 17, 18, 19}; // Input pin numbers (14-19)

LiquidCrystal_I2C lcd(0x27, 16, 2); // I2C LCD display, replace the address (0x27) if different

bool testRunning = false;

void displayMessage(const char* message, int col, int row) {
  lcd.setCursor(col, row);
  lcd.print(message);
}

void startTest() {
  testRunning = true;
  lcd.clear();
  displayMessage("Test Running...", 0, 0);
  delay(2000); // Display "Test Running..." message for 2 seconds

  lcd.clear();
  displayMessage("Double Checking", 0, 0);
  displayMessage("Please Wait...", 0, 1);
  delay(2000); // Display "Double Checking" message for 2 seconds

  lcd.clear();
  displayMessage("Test Ready!", 0, 0);
  displayMessage("Press End Button", 0, 1);
}
void endTest() {
  testRunning = false;
  lcd.clear();
  lcd.print("Results: ");
  int numConnected = 0; // Counter for the number of successful connections
  int failedPins[numPins];
  int numFailedPins = 0;
  
  // Perform the test and check the connections
  for (int i = 0; i < numPins; i++) {
    pinMode(outputPins[i], OUTPUT);
    digitalWrite(outputPins[i], HIGH);
    delay(50); // Allow time for the output to stabilize
    
    pinMode(inputPins[i], INPUT);
    bool connected = digitalRead(inputPins[i]) == HIGH;
    lcd.setCursor(i, 1);
    lcd.print(connected ? "O" : "X");
    
    digitalWrite(outputPins[i], LOW); // Reset output pin
    
    if (connected) {
      numConnected++; // Increment the counter for successful connections
    } else {
      failedPins[numFailedPins++] = i; // Record the failed pin number
    }
  }

  delay(2000); // Display results for 2 seconds
  lcd.clear();

  if (numConnected == numPins) {
    lcd.print("PASS");
    delay(2000); // Display "PASS" for 2 seconds
    lcd.clear();
    lcd.print("Result: ");
    lcd.print(numConnected);
    lcd.print("/");
    lcd.print(numPins);
    delay(2000); // Display "FAIL" for 2 seconds
    lcd.clear();
    lcd.print("No Error"); // Display "No Error" for "PASS"
  } else {
    lcd.print("FAIL");
    delay(2000); // Display "FAIL" for 2 seconds
    lcd.clear();
    lcd.print("Error Pins:");
    for (int i = 0; i < numFailedPins; i++) {
      int failedOutputPin = outputPins[failedPins[i]];
      int failedInputPin = inputPins[failedPins[i]];
      lcd.clear();
      lcd.print("Result: ");
      lcd.print(numConnected);
      lcd.print("/");
      lcd.print(numPins);
     delay(2000); // Display "FAIL" for 2 seconds
      lcd.clear();
       // Display failed output pin in the first column
      lcd.setCursor(0, 0);
      lcd.print("Missing Link ");
      // Display failed input pin in the second column
      lcd.setCursor(0, 1); // Adjust the column number as needed based on your LCD dimensions
      lcd.print("Pin ");
      lcd.print(failedOutputPin);
      lcd.print(" to Pin ");
      lcd.print(failedInputPin);
      delay(2000); // Display each failed pin for 2 seconds
    }
  }
}

void setup() {
  pinMode(startButtonPin, INPUT_PULLUP);
  pinMode(endButtonPin, INPUT_PULLUP);
  lcd.begin(16, 2);
  displayMessage("Press Start", 0, 0);
  displayMessage("To Begin", 1, 1);
}

void loop() {
  if (!testRunning && digitalRead(startButtonPin) == LOW) {
    startTest();
  }
  
  if (testRunning && digitalRead(endButtonPin) == LOW) {
    endTest();
    // Wait for the end button to be released before allowing a new test
    while (digitalRead(endButtonPin) == LOW) {
      // Continue checking end button state until it's released
    }
  }
}