#include <LedControl.h>

LedControl lc = LedControl(12, 11, 10, 2);

// ---------------- GAME STATE ----------------
int ballX = 7, ballY = 3;
int dirX = 1, dirY = 1;

int playerPaddleY = 3;
int aiPaddleY = 3;

int playerScore = 0;
int aiScore = 0;

// ---------------- CONSTANTS ----------------
const int paddleSize = 3;
const int maxScore = 9;

// Timing (ms)
unsigned long lastBallMove = 0;
unsigned long lastPaddleMove = 0;
unsigned long lastFrame = 0;

const int originalBallInterval = 180;   // ORIGINAL SPEED
int ballInterval = originalBallInterval;

int paddleInterval = 60;

// -------- AI DIFFICULTY --------
// 1 = Easy
// 2 = Medium
// 3 = Hard
int aiDifficulty = 1;

// Serve control
bool serving = true;
unsigned long serveStart = 0;

// ---------------- SETUP ----------------
void setup() {  
  lc.shutdown(0, false);
  lc.shutdown(1, false);
  lc.setIntensity(0, 8);
  lc.setIntensity(1, 8);
  lc.clearDisplay(0);
  lc.clearDisplay(1);

  randomSeed(analogRead(A5));

  showTitle();
  startServe();
}

// ---------------- MAIN LOOP ----------------
void loop() {
  unsigned long now = millis();

  readPlayer();

  if (!serving && now - lastBallMove > ballInterval) {
    moveBall();
    checkCollisions();
    lastBallMove = now;
  }

  if (now - lastPaddleMove > paddleInterval) {
    moveAI();
    lastPaddleMove = now;
  }

  if (now - lastFrame > 30) {
    drawGame();
    lastFrame = now;
  }
}

// ---------------- INPUT ----------------
void readPlayer() {
  playerPaddleY = map(
    analogRead(A0),
    0, 1023,
    0, 8 - paddleSize
  );
}

// ---------------- AI ----------------
void moveAI() {
  int aiSpeed;
  int aiError;

  // Difficulty behavior
  if (aiDifficulty == 1) {          // EASY
    aiSpeed = 1;
    aiError = 3;
  }
  else if (aiDifficulty == 2) {     // MEDIUM
    aiSpeed = 1;
    aiError = 1;
  }
  else {                            // HARD
    aiSpeed = 2;
    aiError = 0;
  }

  if (dirX > 0 && !serving) {
    int targetY = ballY + random(-aiError, aiError + 1);

    if (aiPaddleY + paddleSize / 2 < targetY) aiPaddleY += aiSpeed;
    else if (aiPaddleY + paddleSize / 2 > targetY) aiPaddleY -= aiSpeed;
  }

  aiPaddleY = constrain(aiPaddleY, 0, 8 - paddleSize);
}

// ---------------- BALL ----------------
void moveBall() {
  ballX += dirX;
  ballY += dirY;
}

void checkCollisions() {
  // Top / bottom
  if (ballY <= 0 || ballY >= 7) dirY = -dirY;

  // Player paddle
  if (ballX == 1 &&
      ballY >= playerPaddleY &&
      ballY < playerPaddleY + paddleSize) {
    dirX = 1;
    speedUp();
  }

  // AI paddle
  if (ballX == 14 &&
      ballY >= aiPaddleY &&
      ballY < aiPaddleY + paddleSize) {
    dirX = -1;
    speedUp();
  }

  // Score
  if (ballX < 0) {
    aiScore++;
    showScore();
    startServe();
  }

  if (ballX > 15) {
    playerScore++;
    showScore();
    startServe();
  }
}

// ---------------- DIFFICULTY SPEED UP ----------------
void speedUp() {
  ballInterval = max(60, ballInterval - 5);
}

// ---------------- SERVE ----------------
void startServe() {
  serving = true;

  // ✅ RESET BALL SPEED AFTER GOAL
  ballInterval = originalBallInterval;

  ballX = 7;
  ballY = random(1, 6);
  dirX = random(0, 2) ? 1 : -1;
  dirY = random(0, 2) ? 1 : -1;

  countdown();
  serving = false;
}

// ---------------- DRAW ----------------
void drawGame() {
  lc.clearDisplay(0);
  lc.clearDisplay(1);

  // Player paddle
  for (int i = 0; i < paddleSize; i++) {
    setPixel(0, playerPaddleY + i, true);
  }

  // AI paddle
  for (int i = 0; i < paddleSize; i++) {
    setPixel(15, aiPaddleY + i, true);
  }

  // Ball
  if (!serving) setPixel(ballX, ballY, true);
}

// ---------------- UTIL ----------------
void setPixel(int x, int y, bool state) {
  x = 15 - x;

  int device = x / 8;
  int col = x % 8;
  lc.setLed(device, y, col, state);
}

// ---------------- UI ----------------
void showTitle() {
  byte title[8][16] = {
    {0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0},
    {1,1,1,0, 0,1,1,0, 1,0,0,1, 0,1,1,1},
    {1,0,1,0, 1,0,0,1, 1,1,0,1, 1,0,0,0},
    {1,1,1,0, 1,0,0,1, 1,1,1,1, 1,0,0,0},
    {1,0,0,0, 1,0,0,1, 1,0,1,1, 1,0,1,1},
    {1,0,0,0, 1,0,0,1, 1,0,0,1, 1,0,0,1},
    {1,0,0,0, 0,1,1,0, 1,0,0,1, 0,1,1,1},
    {0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0},
  };

  lc.clearDisplay(0);
  lc.clearDisplay(1);

  for (int y = 0; y < 8; y++) {
    for (int x = 0; x < 16; x++) {
      setPixel(x, y, title[y][x]);
    }
  }

  delay(2000);
}

// ---------------- SCORE DISPLAY ----------------
void showScore() {
  lc.clearDisplay(0);
  lc.clearDisplay(1);

  for (int i = 0; i < playerScore; i++) {
    lc.setLed(0, 7, i, true);
  }

  for (int i = 0; i < aiScore; i++) {
    lc.setLed(1, 7, i, true);
  }

  delay(1000);
}

// ---------------- COUNTDOWN ----------------
void countdown() {
  for (int i = 3; i > 0; i--) {
    lc.clearDisplay(0);
    lc.clearDisplay(1);
    setPixel(7, 3, true);
    delay(300);
    lc.clearDisplay(0);
    lc.clearDisplay(1);
    delay(300);
  }
}





/*#include <LedControl.h>

LedControl lc = LedControl(12, 11, 10, 2);

// ---------------- GAME STATE ----------------
int ballX = 7, ballY = 3;
int dirX = 1, dirY = 1;

int playerPaddleY = 3;
int aiPaddleY = 3;

int playerScore = 0;
int aiScore = 0;

// ---------------- CONSTANTS ----------------
const int paddleSize = 3;
const int maxScore = 9;

// Timing (ms)
unsigned long lastBallMove = 0;
unsigned long lastPaddleMove = 0;
unsigned long lastFrame = 0;

int ballInterval = 180;      // gets faster over time
int paddleInterval = 60;

// AI tuning
int aiSpeed = 1;
int aiError = 2;

// Serve control
bool serving = true;
unsigned long serveStart = 0;

// ---------------- SETUP ----------------
void setup() {
  lc.shutdown(0, false);
  lc.shutdown(1, false);
  lc.setIntensity(0, 8);
  lc.setIntensity(1, 8);
  lc.clearDisplay(0);
  lc.clearDisplay(1);

  randomSeed(analogRead(A5));

  showTitle();
  startServe();
}

// ---------------- MAIN LOOP ----------------
void loop() {
  unsigned long now = millis();

  readPlayer();

  if (!serving && now - lastBallMove > ballInterval) {
    moveBall();
    checkCollisions();
    lastBallMove = now;
  }

  if (now - lastPaddleMove > paddleInterval) {
    moveAI();
    lastPaddleMove = now;
  }

  if (now - lastFrame > 30) {
    drawGame();
    lastFrame = now;
  }
}

// ---------------- INPUT ----------------
void readPlayer() {
  playerPaddleY = map(
    analogRead(A0),
    0, 1023,
    0, 8 - paddleSize
  );
}

// ---------------- AI ----------------
void moveAI() {
  if (dirX > 0 && !serving) {
    int targetY = ballY + random(-aiError, aiError + 1);

    if (aiPaddleY + paddleSize / 2 < targetY) aiPaddleY += aiSpeed;
    else if (aiPaddleY + paddleSize / 2 > targetY) aiPaddleY -= aiSpeed;
  }

  aiPaddleY = constrain(aiPaddleY, 0, 8 - paddleSize);
}

// ---------------- BALL ----------------
void moveBall() {
  ballX += dirX;
  ballY += dirY;
}

void checkCollisions() {
  // Top / bottom
  if (ballY <= 0 || ballY >= 7) dirY = -dirY;

  // Player paddle
  if (ballX == 1 &&
      ballY >= playerPaddleY &&
      ballY < playerPaddleY + paddleSize) {
    dirX = 1;
    speedUp();
  }

  // AI paddle
  if (ballX == 14 &&
      ballY >= aiPaddleY &&
      ballY < aiPaddleY + paddleSize) {
    dirX = -1;
    speedUp();
  }

  // Score
  if (ballX < 0) {
    aiScore++;
    showScore();
    startServe();
  }

  if (ballX > 15) {
    playerScore++;
    showScore();
    startServe();
  }
}

// ---------------- DIFFICULTY ----------------
void speedUp() {
  ballInterval = max(60, ballInterval - 5);
  aiError = max(0, aiError - 1);
}

// ---------------- SERVE ----------------
void startServe() {
  serving = true;

  // Reset ball speed after goal
  ballInterval = originalBallInterval;

  ballX = 7;
  ballY = random(1, 6);
  dirX = random(0, 2) ? 1 : -1;
  dirY = random(0, 2) ? 1 : -1;

  countdown();
  serving = false;
}


// ---------------- DRAW ----------------
void drawGame() {
  lc.clearDisplay(0);
  lc.clearDisplay(1);

  // Player paddle
  for (int i = 0; i < paddleSize; i++) {
    setPixel(0, playerPaddleY + i, true);
  }

  // AI paddle
  for (int i = 0; i < paddleSize; i++) {
    setPixel(15, aiPaddleY + i, true);
  }

  // Ball
  if (!serving) setPixel(ballX, ballY, true);
}

// ---------------- UTIL ----------------
void setPixel(int x, int y, bool state) {
  x = 15 - x;               // <-- mirror horizontally

  int device = x / 8;
  int col = x % 8;
  lc.setLed(device, y, col, state);
}


// ---------------- UI ----------------
void showTitle() {
  // Proper P O N G (16x8)
  byte title[8][16] = {
    // P        O        N        G
    {0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0},
    {1,1,1,0, 0,1,1,0, 1,0,0,1, 0,1,1,1},
    {1,0,1,0, 1,0,0,1, 1,1,0,1, 1,0,0,0},
    {1,1,1,0, 1,0,0,1, 1,1,1,1, 1,0,0,0},
    {1,0,0,0, 1,0,0,1, 1,0,1,1, 1,0,1,1},
    {1,0,0,0, 1,0,0,1, 1,0,0,1, 1,0,0,1},
    {1,0,0,0, 0,1,1,0, 1,0,0,1, 0,1,1,1},
    {0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0},
  };

  lc.clearDisplay(0);
  lc.clearDisplay(1);

  for (int y = 0; y < 8; y++) {
    for (int x = 0; x < 16; x++) {
      setPixel(x, y, title[y][x]);
    }
  }

  delay(2000);
}



// ---------------- SCORE DISPLAY ----------------
void showScore() {
  lc.clearDisplay(0);
  lc.clearDisplay(1);

  for (int i = 0; i < playerScore; i++) {
    lc.setLed(0, 7, i, true);
  }

  for (int i = 0; i < aiScore; i++) {
    lc.setLed(1, 7, i, true);
  }

  delay(1000);
}

// ---------------- COUNTDOWN ----------------
void countdown() {
  for (int i = 3; i > 0; i--) {
    lc.clearDisplay(0);
    lc.clearDisplay(1);
    setPixel(7, 3, true);
    delay(300);
    lc.clearDisplay(0);
    lc.clearDisplay(1);
    delay(300);
  }
}
*/