#include <LedControl.h>

#define DATA_IN 2
#define CLK 3
#define CS 4

LedControl lc = LedControl(DATA_IN, CLK, CS, 1);

const int joystickX = A0; // Joystick X-axis
const int joystickY = A1; // Joystick Y-axis

const int gridSize = 8; // 8x8 grid size
int snakeX[gridSize * gridSize]; // Snake X positions
int snakeY[gridSize * gridSize]; // Snake Y positions
int snakeLength = 1; // Initial snake length
int foodX, foodY; // Food position
int dirX = 0, dirY = 1; // Initial direction

void setup() {
  lc.shutdown(0, false);       // Wake up the MAX72XX
  lc.setIntensity(0, 8);       // Set brightness level (0 is min, 15 is max)
  lc.clearDisplay(0);          // Clear display register

  randomSeed(analogRead(0)); // Seed for random food placement
  placeFood();
}

void loop() {
  readJoystick();
  moveSnake();
  
  // Draw snake
  lc.clearDisplay(0);
  for (int i = 0; i < snakeLength; i++) {
    lc.setLed(0, snakeY[i], snakeX[i], true);
  }
  
  // Draw food
  lc.setLed(0, foodY, foodX, true);
  
  // Check for collision with food
  if (snakeX[0] == foodX && snakeY[0] == foodY) {
    snakeLength++;
    placeFood();
  }
  
  delay(200); // Adjust speed
}

void readJoystick() {
  int x = analogRead(joystickX);
  int y = analogRead(joystickY);
  
  if (x < 100) dirX = -1, dirY = 0; // Left
  else if (x > 900) dirX = 1, dirY = 0; // Right
  else if (y < 100) dirX = 0, dirY = 1; // Up (changed direction here)
  else if (y > 900) dirX = 0, dirY = -1; // Down (changed direction here)
}

void moveSnake() {
  for (int i = snakeLength; i > 0; i--) {
    snakeX[i] = snakeX[i - 1];
    snakeY[i] = snakeY[i - 1];
  }
  
  snakeX[0] += dirX;
  snakeY[0] += dirY;

  // Check for wall collision
  if (snakeX[0] < 0) snakeX[0] = gridSize - 1;
  if (snakeX[0] >= gridSize) snakeX[0] = 0;
  if (snakeY[0] < 0) snakeY[0] = gridSize - 1;
  if (snakeY[0] >= gridSize) snakeY[0] = 0;

  // Check for self-collision
  for (int i = 1; i < snakeLength; i++) {
    if (snakeX[0] == snakeX[i] && snakeY[0] == snakeY[i]) {
      snakeLength = 1; // Reset game on collision
    }
  }
}

void placeFood() {
  foodX = random(0, gridSize);
  foodY = random(0, gridSize);
}