// Pin definitions
const int btn1Pin = 2;  // Button 1 (Lowest bit)
const int btn2Pin = 3;  // Button 2 (Middle bit)
const int btn3Pin = 4;  // Button 3 (Highest bit)

const int led1Pin = 5;  // LED 1 (Lowest bit)
const int led2Pin = 6;  // LED 2 (Middle bit)
const int led3Pin = 7;  // LED 3 (Highest bit)

const int barPins[] = {8, 9, 10, 11, 12, 13, 44};  // Bar graph pins A1-A7 for values 1-7

// Variables for button state and timing
bool btn1State = false;
bool btn2State = false;
bool btn3State = false;

bool btn1LastState = HIGH;  // HIGH = not pressed, LOW = pressed
bool btn2LastState = HIGH;
bool btn3LastState = HIGH;

unsigned long btn1PressTime = 0;
unsigned long btn2PressTime = 0;
unsigned long btn3PressTime = 0;

const unsigned long minPressDuration = 150;  // 0.15 seconds in milliseconds

void setup() {
  // Initialize button pins as inputs with pull-up resistors
  pinMode(btn1Pin, INPUT_PULLUP);
  pinMode(btn2Pin, INPUT_PULLUP);
  pinMode(btn3Pin, INPUT_PULLUP);
  
  // Initialize LED pins as outputs
  pinMode(led1Pin, OUTPUT);
  pinMode(led2Pin, OUTPUT);
  pinMode(led3Pin, OUTPUT);
  
  // Initialize bar graph pins as outputs
  for(int i = 0; i < 7; i++) {
    pinMode(barPins[i], OUTPUT);
    digitalWrite(barPins[i], LOW);  // Start with all segments off
  }
  
  // Start with all LEDs off
  digitalWrite(led1Pin, LOW);
  digitalWrite(led2Pin, LOW);
  digitalWrite(led3Pin, LOW);
}

void loop() {
  // Read button states
  bool btn1Reading = digitalRead(btn1Pin);
  bool btn2Reading = digitalRead(btn2Pin);
  bool btn3Reading = digitalRead(btn3Pin);
  
  // Handle button 1
  if(btn1Reading != btn1LastState) {  // Button state has changed
    if(btn1Reading == LOW) {  // Button was pressed
      btn1PressTime = millis();
    } else {  // Button was released
      if((millis() - btn1PressTime) >= minPressDuration) {  // Press was long enough
        btn1State = !btn1State;  // Toggle button state
        digitalWrite(led1Pin, btn1State ? HIGH : LOW);  // Update LED
        updateBarGraph();  // Update bar graph
      }
    }
    btn1LastState = btn1Reading;
  }
  
  // Handle button 2
  if(btn2Reading != btn2LastState) {  // Button state has changed
    if(btn2Reading == LOW) {  // Button was pressed
      btn2PressTime = millis();
    } else {  // Button was released
      if((millis() - btn2PressTime) >= minPressDuration) {  // Press was long enough
        btn2State = !btn2State;  // Toggle button state
        digitalWrite(led2Pin, btn2State ? HIGH : LOW);  // Update LED
        updateBarGraph();  // Update bar graph
      }
    }
    btn2LastState = btn2Reading;
  }
  
  // Handle button 3
  if(btn3Reading != btn3LastState) {  // Button state has changed
    if(btn3Reading == LOW) {  // Button was pressed
      btn3PressTime = millis();
    } else {  // Button was released
      if((millis() - btn3PressTime) >= minPressDuration) {  // Press was long enough
        btn3State = !btn3State;  // Toggle button state
        digitalWrite(led3Pin, btn3State ? HIGH : LOW);  // Update LED
        updateBarGraph();  // Update bar graph
      }
    }
    btn3LastState = btn3Reading;
  }
}

void updateBarGraph() {
  // Calculate the decimal value from the binary state
  int decimalValue = (btn3State ? 4 : 0) + (btn2State ? 2 : 0) + (btn1State ? 1 : 0);
  
  // Turn off all segments
  for(int i = 0; i < 7; i++) {
    digitalWrite(barPins[i], LOW);
  }
  
  // Turn on the corresponding segment for values 1-7
  if(decimalValue >= 1 && decimalValue <= 7) {
    digitalWrite(barPins[decimalValue - 1], HIGH);
  }
}