Snake Game with Matrix Display and push button with Arduino

#include <LedControl.h>  // MAX7219 control library
 
// Define MAX7219 pins
#define DATA_IN 12
#define CLK 10
#define CS 11
 
 
LedControl lc = LedControl(DIN_PIN, CLK_PIN, CS_PIN, 1);
 
// Push buttons
#define UP_BTN 3
#define DOWN_BTN 4
#define LEFT_BTN 5
#define RIGHT_BTN 2
 
// Game variables
int snake[64][2]; // Snake body (maximum length 64)
int snakeLength = 2; // Starting length of the snake
int direction = 1;   // 0=UP, 1=RIGHT, 2=DOWN, 3=LEFT
int foodX, foodY;
bool isGameOver = false;
 
void setup() {
  // Initialize MAX7219
  lc.shutdown(0, false);
  lc.setIntensity(0, 8);  // Set brightness (0-15)
  lc.clearDisplay(0);
 
  // Initialize buttons
  pinMode(UP_BTN, INPUT_PULLUP);
  pinMode(DOWN_BTN, INPUT_PULLUP);
  pinMode(LEFT_BTN, INPUT_PULLUP);
  pinMode(RIGHT_BTN, INPUT_PULLUP);
 
  // Initialize Serial Monitor
  Serial.begin(9600);
  Serial.println("Game Started! Use buttons to control the snake.");
   
  // Initialize snake position
  snake[0][0] = 3; snake[0][1] = 3; // Head
  snake[1][0] = 3; snake[1][1] = 2; // Body
 
  generateFood(); // Generate the first food
}
 
void loop() {
  if (isGameOver) {
    gameOver();
    return;
  }
 
  // Read buttons for direction
  if (!digitalRead(UP_BTN) && direction != 2) direction = 0;
  if (!digitalRead(RIGHT_BTN) && direction != 3) direction = 1;
  if (!digitalRead(DOWN_BTN) && direction != 0) direction = 2;
  if (!digitalRead(LEFT_BTN) && direction != 1) direction = 3;
 
  moveSnake();
 
  if (checkCollision()) {
    isGameOver = true;
    return;
  }
 
  if (checkFood()) {
    snakeLength++;
    Serial.print("Food eaten! New length: ");
    Serial.println(snakeLength);
    generateFood();
  }
 
  displaySnake();
  delay(300); // Adjust speed of the game
}
 
void moveSnake() {
  // Move body
  for (int i = snakeLength - 1; i > 0; i--) {
    snake[i][0] = snake[i - 1][0];
    snake[i][1] = snake[i - 1][1];
  }
 
  // Move head
  if (direction == 0) snake[0][0]--; // UP
  if (direction == 1) snake[0][1]++; // RIGHT
  if (direction == 2) snake[0][0]++; // DOWN
  if (direction == 3) snake[0][1]--; // LEFT
 
  // Print direction to Serial Monitor
  Serial.print("Snake moved: ");
  if (direction == 0) Serial.println("UP");
  if (direction == 1) Serial.println("RIGHT");
  if (direction == 2) Serial.println("DOWN");
  if (direction == 3) Serial.println("LEFT");
}
 
bool checkCollision() {
  // Check wall collision
  if (snake[0][0] < 0 || snake[0][0] >= 8 || snake[0][1] < 0 || snake[0][1] >= 8) {
    Serial.println("Collision with wall! Game Over.");
    return true;
  }
  // Check self-collision
  for (int i = 1; i < snakeLength; i++) {
    if (snake[0][0] == snake[i][0] && snake[0][1] == snake[i][1]) {
      Serial.println("Collision with self! Game Over.");
      return true;
    }
  }
  return false;
}
 
bool checkFood() {
  return snake[0][0] == foodX && snake[0][1] == foodY;
}
 
void generateFood() {
  do {
    foodX = random(0, 8);
    foodY = random(0, 8);
  } while (isFoodOnSnake());
 
  Serial.print("New food generated at: (");
  Serial.print(foodX);
  Serial.print(", ");
  Serial.print(foodY);
  Serial.println(")");
}
 
bool isFoodOnSnake() {
  for (int i = 0; i < snakeLength; i++) {
    if (foodX == snake[i][0] && foodY == snake[i][1]) {
      return true;
    }
  }
  return false;
}
 
void displaySnake() {
  lc.clearDisplay(0);
 
  // Display snake
  for (int i = 0; i < snakeLength; i++) {
    lc.setLed(0, snake[i][0], snake[i][1], true);
  }
 
  // Display food
  lc.setLed(0, foodX, foodY, true);
}
 
void gameOver() {
  lc.clearDisplay(0);
  for (int i = 0; i < 8; i++) {
    for (int j = 0; j < 8; j++) {
      lc.setLed(0, i, j, true);
    }
  }
  Serial.println("Game Over! Restarting...");
  delay(3000);
  setup(); // Restart the game
}