#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128  // OLED display width, in pixels
#define SCREEN_HEIGHT 64  // OLED display height, in pixels
#define OLED_RESET    -1  // Reset pin # (or -1 if sharing Arduino reset pin)
#define SCREEN_ADDRESS 0x3C  // I2C address for the SSD1306 OLED

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

// Ultrasonic sensor pins
#define TRIG_PIN 7
#define ECHO_PIN 6

// Game variables
int birdY = SCREEN_HEIGHT / 2; // Bird's vertical position
int birdX = 20;                // Bird's horizontal position
int obstacleX = SCREEN_WIDTH;  // Obstacle's horizontal position
int obstacleGapY;              // Obstacle's gap vertical position
const int obstacleGapSize = 20; // Size of the gap in the obstacle
bool gameOver = false;

// Timing variables
unsigned long lastObstacleUpdate = 0;
unsigned long lastFrameUpdate = 0;

// Function prototypes
void resetGame();
void updateGame();
void drawGame();
int getDistance();

void setup() {
  Serial.begin(9600);

  // Initialize OLED display
  if (!display.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS)) {
    Serial.println(F("SSD1306 allocation failed"));
    for (;;);
  }

  display.clearDisplay();
  display.display();

  // Initialize ultrasonic sensor
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);

  // Start the game
  resetGame();
}

void loop() {
  if (!gameOver) {
    updateGame();
    drawGame();
  }
}

void resetGame() {
  birdY = SCREEN_HEIGHT / 2;
  obstacleX = SCREEN_WIDTH;
  obstacleGapY = random(10, SCREEN_HEIGHT - obstacleGapSize - 10);
  gameOver = false;
}

void updateGame() {
  unsigned long currentTime = millis();

  // Update bird position based on ultrasonic distance
  int distance = getDistance();
  birdY = map(constrain(distance, 1, 30), 1, 30, 0, SCREEN_HEIGHT - 1);

  // Update obstacle position
  if (currentTime - lastObstacleUpdate > 50) {
    obstacleX -= 2; // Move obstacle to the left
    if (obstacleX < -10) { // Reset obstacle when it goes off screen
      obstacleX = SCREEN_WIDTH;
      obstacleGapY = random(10, SCREEN_HEIGHT - obstacleGapSize - 10);
    }
    lastObstacleUpdate = currentTime;
  }

  // Check for collisions
  if (birdY < 0 || birdY > SCREEN_HEIGHT - 1 || 
      (birdX + 5 > obstacleX && birdX < obstacleX + 10 && 
       (birdY < obstacleGapY || birdY > obstacleGapY + obstacleGapSize))) {
    gameOver = true;
  }
}

void drawGame() {
  display.clearDisplay();

  // Draw the bird as a small rectangle
  display.fillRect(birdX, birdY, 5, 5, SSD1306_WHITE);

  // Draw the obstacle
  display.fillRect(obstacleX, 0, 10, obstacleGapY, SSD1306_WHITE); // Top part
  display.fillRect(obstacleX, obstacleGapY + obstacleGapSize, 10, SCREEN_HEIGHT, SSD1306_WHITE); // Bottom part

  // Display "Game Over" if game ends
  if (gameOver) {
    display.setTextSize(1);
    display.setTextColor(SSD1306_WHITE);
    display.setCursor(20, SCREEN_HEIGHT / 2 - 10);
    display.print("GAME OVER");
    display.setCursor(20, SCREEN_HEIGHT / 2 + 10);
    display.print("Reset Arduino");
  }

  display.display();
}

int getDistance() {
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);

  long duration = pulseIn(ECHO_PIN, HIGH);
  int distance = duration * 0.034 / 2; // Convert to centimeters
  return distance;
}