#include <Keypad.h>
#include <Servo.h>

// Keypad settings
const byte ROWS = 4; // 4 rows
const byte COLS = 4; // 4 columns
char keys[ROWS][COLS] = {
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}
};
byte rowPins[ROWS] = {2, 3, 4, 5}; // Connect to the row pinouts of the keypad
byte colPins[COLS] = {6, 7, 8, 9}; // Connect to the column pinouts of the keypad

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

// Servo settings
Servo servo1;
Servo servo2;
Servo servo3;

void setup() {
  // Attach servos to respective pins
  servo1.attach(10);
  servo2.attach(11);
  servo3.attach(12);

  // Initialize servos in closed position
  servo1.write(0);
  servo2.write(0);
  servo3.write(0);

  Serial.begin(9600);
  Serial.println("Vending Machine Ready. Enter item code:");
}

void loop() {
  char key = keypad.getKey(); // Read keypress
  
  if (key) { // If a key is pressed
    Serial.print("Key pressed: ");
    Serial.println(key);

    // Dispense item based on input
    if (key == '1') {
      Serial.println("Dispensing Item 1");
      dispenseItem(servo1);
    } else if (key == '2') {
      Serial.println("Dispensing Item 2");
      dispenseItem(servo2);
    } else if (key == '3') {
      Serial.println("Dispensing Item 3");
      dispenseItem(servo3);
    } else {
      Serial.println("Invalid Code");
    }
  }
}

void dispenseItem(Servo &servo) {
  servo.write(90); // Open slot
  delay(6000);     // Wait for item to drop
  servo.write(0);  // Close slot
}