#include <Adafruit_GFX.h>
#include <Adafruit_ILI9341.h>
#include <SPI.h>

// Pin definitions for the TFT display and joystick
#define TFT_CS     10
#define TFT_RST    9
#define TFT_DC     8
#define JOY_X      A0
#define JOY_Y      A1
#define BUTTON_PIN 2 // Joystick button

// Create TFT display object
Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC, TFT_RST);

// Snake properties
int snakeX[100], snakeY[100]; // Snake coordinates
int snakeLength = 1;          // Initial snake length
int foodX, foodY;             // Food coordinates
int redFoodX, redFoodY;       // Red food coordinates for Level 4
bool redFoodActive = false;   // Red food status for Level 4
int score = 0;                // Player score
int level = 1;                // Game level
int direction = 1;            // Initial direction (0: up, 1: right, 2: down, 3: left)
bool foodActive = false;      // Tracks if food is currently active

// Barrier properties for Level 2
int barrierX, barrierY;       // Barrier coordinates for Level 2
const int barrierDigit = 7;   // Example digit for barrier (replace with actual last digit)
bool barrierActive = false;

// Timer variables for food disappearance in Level 3
unsigned long foodTimer = 0;  // Timer for food
int foodCountdown = 5;        // Food countdown in seconds

void setup() {
  tft.begin();
  tft.setRotation(3);
  tft.fillScreen(ILI9341_BLACK);

  // Initialize joystick button pin
  pinMode(BUTTON_PIN, INPUT_PULLUP);

  // Initial snake position
  snakeX[0] = tft.width() / 2;
  snakeY[0] = tft.height() / 2;

  spawnFood(); // Spawn initial food
}

void spawnFood() {
  do {
    foodX = random(0, tft.width() / 10) * 10;
    foodY = random(0, tft.height() / 10) * 10;
  } while (level == 2 && isFoodTooCloseToBarrier(foodX, foodY)); // Only check for Level 2

  foodActive = true;         // Food is active
  foodCountdown = 5;         // Reset countdown to 5 seconds
  foodTimer = millis();      // Record the time when food is spawned
}

void spawnRedFood() {
  redFoodX = random(0, tft.width() / 10) * 10;
  redFoodY = random(0, tft.height() / 10) * 10;
  redFoodActive = true;
}

bool isFoodTooCloseToBarrier(int foodX, int foodY) {
  if (barrierActive) {
    return (abs(foodX - barrierX) < 10 && abs(foodY - barrierY) < 10);
  }
  return false;
}

void spawnBarrier() {
  barrierX = random(0, tft.width() / 10) * 10;
  barrierY = random(0, tft.height() / 10) * 10;

  if (snakeX[0] > tft.width() / 4 && snakeX[0] < 3 * tft.width() / 4 &&
      snakeY[0] > tft.height() / 4 && snakeY[0] < 3 * tft.height() / 4) {
    snakeX[0] = 10; // Move to top-left corner
    snakeY[0] = 10;
  }

  barrierActive = true;
}

void drawSnake() {
  for (int i = 0; i < snakeLength; i++) {
    tft.fillRect(snakeX[i], snakeY[i], 10, 10, ILI9341_BLUE);
  }
}

void clearSnake() {
  for (int i = 0; i < snakeLength; i++) {
    tft.fillRect(snakeX[i], snakeY[i], 10, 10, ILI9341_BLACK);
  }
}

void drawFood() {
  if (foodActive) {
    tft.fillRect(foodX, foodY, 10, 10, ILI9341_GREEN);
  }
}

void drawRedFood() {
  if (redFoodActive && level >= 4) {
    tft.fillRect(redFoodX, redFoodY, 10, 10, ILI9341_RED);
  }
}

void drawBarrier() {
  if (barrierActive && level == 2) {
    tft.setTextColor(ILI9341_WHITE);
    tft.setTextSize(3);
    tft.setCursor(barrierX, barrierY);
    tft.print(barrierDigit);
  }
}

void displayScoreAndCountdown() {
  tft.setCursor(0, 0);
  tft.setTextColor(ILI9341_WHITE);
  tft.setTextSize(2);
  tft.print("Score: ");
  tft.print(score);
  tft.print("  Level: ");
  tft.print(level);

  if (level == 3 && foodActive) {
    tft.setCursor(180, 0);
    tft.print("Timer: ");
    tft.print(foodCountdown);
  }
}

void updateSnake() {
  for (int i = snakeLength; i > 0; i--) {
    snakeX[i] = snakeX[i - 1];
    snakeY[i] = snakeY[i - 1];
  }

  switch (direction) {
    case 0: snakeY[0] -= 10; break; // Up
    case 1: snakeX[0] += 10; break; // Right
    case 2: snakeY[0] += 10; break; // Down
    case 3: snakeX[0] -= 10; break; // Left
  }

  if (snakeX[0] >= tft.width()) snakeX[0] = 0;
  if (snakeX[0] < 0) snakeX[0] = tft.width() - 10;
  if (snakeY[0] >= tft.height()) snakeY[0] = 0;
  if (snakeY[0] < 0) snakeY[0] = tft.height() - 10;
}

bool checkCollision() {
  for (int i = 1; i < snakeLength; i++) {
    if (snakeX[0] == snakeX[i] && snakeY[0] == snakeY[i]) {
      return true;
    }
  }

  if (level == 2 && barrierActive) {
    if (snakeX[0] >= barrierX && snakeX[0] < barrierX + 20 &&
        snakeY[0] >= barrierY && snakeY[0] < barrierY + 24) {
      return true;
    }
  }

  return false;
}

void updateFoodTimer() {
  if (level == 3 && foodActive) {
    barrierActive = false;
    if (millis() - foodTimer >= 1000) {
      foodTimer = millis();
      foodCountdown--;

      if (foodCountdown <= 0) {
        tft.fillRect(foodX, foodY, 10, 10, ILI9341_BLACK);
        foodActive = false;
      }
    }
  }
}

void loop() {
  clearSnake();
  updateSnake();
  drawSnake();

  if (snakeX[0] == foodX && snakeY[0] == foodY && foodActive) {
    snakeLength++;
    score++;
    spawnFood();
    level = score / 2 + 1;

    if (level == 2 && !barrierActive) {
      spawnBarrier();
    }

    if (level >= 4 && !redFoodActive && random(0, 5) == 0) {
      spawnRedFood();
    }
  }

  if (snakeX[0] == redFoodX && snakeY[0] == redFoodY && redFoodActive) {
    snakeLength--;
    score--;
    redFoodActive = false;
  }

  if (checkCollision()) {
    tft.setCursor(50, 50);
    tft.setTextColor(ILI9341_WHITE);
    tft.setTextSize(3);
    tft.print("Game Over!");
    delay(3000);
    while (1);
  }

  drawFood();
  drawRedFood();
  displayScoreAndCountdown();
  drawBarrier();
  updateFoodTimer();

  delay(200 - level * 10);
}