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

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1

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

// Button pins
const int BTN_FEED = 2;
const int BTN_PLAY = 3;
const int BTN_SLEEP = 4;

// Buzzer pin
const int BUZZER = 8;

// Pet stats
int hunger = 50;
int happiness = 70;
int energy = 80;
int age = 0;

// Animation
int frame = 0;
unsigned long lastUpdate = 0;
unsigned long lastAnim = 0;

// Sound enabled flag
bool soundEnabled = true;

void setup() {
  Serial.begin(9600);
  Serial.println("Starting Virtual Pet with Sounds...");
  
  // Setup buttons
  pinMode(BTN_FEED, INPUT_PULLUP);
  pinMode(BTN_PLAY, INPUT_PULLUP);
  pinMode(BTN_SLEEP, INPUT_PULLUP);
  
  // Setup buzzer
  pinMode(BUZZER, OUTPUT);
  
  // Initialize display
  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println("Display failed!");
    for(;;);
  }
  
  Serial.println("Display OK!");
  display.clearDisplay();
  display.setTextColor(SSD1306_WHITE);
  
  // Show welcome screen with startup sound
  playStartupSound();
  display.setTextSize(2);
  display.setCursor(10, 20);
  display.println("Virtual");
  display.setCursor(25, 40);
  display.println("Pet!");
  display.display();
  delay(2000);
}

void loop() {
  unsigned long now = millis();
  
  // Update stats every 5 seconds
  if (now - lastUpdate > 5000) {
    hunger = min(100, hunger + 3);
    happiness = max(0, happiness - 2);
    energy = max(0, energy - 2);
    age++;
    lastUpdate = now;
    
    // Warning beep if stats getting critical
    if (hunger > 80 || happiness < 20 || energy < 20) {
      playWarningSound();
    }
    
    Serial.print("H:"); Serial.print(hunger);
    Serial.print(" E:"); Serial.print(happiness);
    Serial.print(" T:"); Serial.println(energy);
  }
  
  // Animation frame
  if (now - lastAnim > 500) {
    frame = (frame + 1) % 2;
    lastAnim = now;
  }
  
  // Check buttons
  if (digitalRead(BTN_FEED) == LOW) {
    hunger = max(0, hunger - 30);
    happiness = min(100, happiness + 5);
    playEatSound();
    showMessage("Fed!");
    delay(500);
  }
  
  if (digitalRead(BTN_PLAY) == LOW) {
    if (energy > 20) {
      happiness = min(100, happiness + 20);
      energy = max(0, energy - 15);
      playHappySound();
      showMessage("Fun!");
      delay(500);
    } else {
      playSadSound();
      showMessage("Too tired!");
      delay(500);
    }
  }
  
  if (digitalRead(BTN_SLEEP) == LOW) {
    energy = min(100, energy + 40);
    playSleepSound();
    showMessage("Zzz...");
    delay(1000);
  }
  
  // Draw screen
  display.clearDisplay();
  
  // Check if dead
  if (hunger >= 100 || happiness <= 0) {
    playDeathSound();
    drawDead();
  } else {
    drawPet();
    drawStats();
    drawButtons();
  }
  
  display.display();
  delay(100);
}

// ============ SOUND FUNCTIONS ============

void playStartupSound() {
  // Happy startup melody
  tone(BUZZER, 523, 150); // C
  delay(150);
  tone(BUZZER, 659, 150); // E
  delay(150);
  tone(BUZZER, 784, 200); // G
  delay(200);
}

void playEatSound() {
  // Eating sound - quick ascending notes
  tone(BUZZER, 400, 100);
  delay(120);
  tone(BUZZER, 500, 100);
  delay(120);
  tone(BUZZER, 600, 100);
  delay(120);
}

void playHappySound() {
  // Happy playful sound
  tone(BUZZER, 800, 100);
  delay(120);
  tone(BUZZER, 1000, 100);
  delay(120);
  tone(BUZZER, 1200, 150);
  delay(170);
}

void playSleepSound() {
  // Sleepy descending melody
  tone(BUZZER, 700, 200);
  delay(220);
  tone(BUZZER, 600, 200);
  delay(220);
  tone(BUZZER, 500, 300);
  delay(320);
}

void playSadSound() {
  // Sad descending notes
  tone(BUZZER, 400, 200);
  delay(220);
  tone(BUZZER, 300, 300);
  delay(320);
}

void playWarningSound() {
  // Warning beep
  tone(BUZZER, 800, 100);
  delay(150);
  tone(BUZZER, 800, 100);
  delay(150);
}

void playDeathSound() {
  // Sad death sound (only plays once)
  static bool deathSoundPlayed = false;
  if (!deathSoundPlayed) {
    tone(BUZZER, 500, 300);
    delay(320);
    tone(BUZZER, 400, 300);
    delay(320);
    tone(BUZZER, 300, 500);
    delay(520);
    deathSoundPlayed = true;
  }
}

// ============ DRAWING FUNCTIONS ============

void drawPet() {
  int x = 64;
  int y = 30;
  
  // Body
  display.fillCircle(x, y, 12, SSD1306_WHITE);
  
  // Determine face based on stats
  if (hunger > 70) {
    // Hungry face
    display.fillCircle(x-4, y-2, 2, SSD1306_BLACK);
    display.fillCircle(x+4, y-2, 2, SSD1306_BLACK);
    display.fillCircle(x, y+4, 3, SSD1306_BLACK); // Open mouth
  } else if (energy < 30) {
    // Tired face
    display.drawLine(x-5, y-2, x-2, y-2, SSD1306_BLACK);
    display.drawLine(x+2, y-2, x+5, y-2, SSD1306_BLACK);
    if (frame == 0) {
      display.setCursor(x+12, y-8);
      display.setTextSize(1);
      display.print("Z");
    }
  } else if (happiness < 40) {
    // Sad face
    display.fillCircle(x-4, y-2, 2, SSD1306_BLACK);
    display.fillCircle(x+4, y-2, 2, SSD1306_BLACK);
    display.drawLine(x-3, y+6, x, y+4, SSD1306_BLACK);
    display.drawLine(x, y+4, x+3, y+6, SSD1306_BLACK);
  } else {
    // Happy face
    display.fillCircle(x-4, y-2, 2, SSD1306_BLACK);
    display.fillCircle(x+4, y-2, 2, SSD1306_BLACK);
    display.drawLine(x-5, y+3, x-2, y+5, SSD1306_BLACK);
    display.drawLine(x-2, y+5, x+2, y+5, SSD1306_BLACK);
    display.drawLine(x+2, y+5, x+5, y+3, SSD1306_BLACK);
    
    // Bounce animation
    if (frame == 0) y -= 2;
  }
  
  // Feet
  display.fillCircle(x-8, y+13, 3, SSD1306_WHITE);
  display.fillCircle(x+8, y+13, 3, SSD1306_WHITE);
  
  // Draw musical note if happy
  if (happiness > 70 && frame == 0) {
    display.setCursor(x+15, y-5);
    display.setTextSize(1);
    display.print((char)3); // Musical note character
  }
}

void drawStats() {
  display.setTextSize(1);
  
  // Hunger (inverted - lower is better)
  display.setCursor(0, 0);
  display.print("H:");
  int h = map(100-hunger, 0, 100, 0, 20);
  display.drawRect(12, 0, 22, 6, SSD1306_WHITE);
  display.fillRect(13, 1, h, 4, SSD1306_WHITE);
  
  // Happiness
  display.setCursor(38, 0);
  display.print("E:");
  int e = map(happiness, 0, 100, 0, 20);
  display.drawRect(50, 0, 22, 6, SSD1306_WHITE);
  display.fillRect(51, 1, e, 4, SSD1306_WHITE);
  
  // Energy
  display.setCursor(76, 0);
  display.print("T:");
  int t = map(energy, 0, 100, 0, 20);
  display.drawRect(88, 0, 22, 6, SSD1306_WHITE);
  display.fillRect(89, 1, t, 4, SSD1306_WHITE);
  
  // Age
  display.setCursor(114, 0);
  display.print(age);
}

void drawButtons() {
  display.setTextSize(1);
  display.setCursor(0, 56);
  display.print("Feed");
  display.setCursor(44, 56);
  display.print("Play");
  display.setCursor(88, 56);
  display.print("Sleep");
}

void drawDead() {
  display.setTextSize(2);
  display.setCursor(20, 15);
  display.println("R.I.P.");
  display.setTextSize(1);
  display.setCursor(10, 35);
  display.println("Pet has died");
  display.setCursor(5, 50);
  display.println("Reset to restart");
}

void showMessage(const char* msg) {
  display.clearDisplay();
  display.setTextSize(2);
  display.setCursor(20, 25);
  display.println(msg);
  display.display();
}