#include <Wire.h>
#include <Adafruit_SSD1306.h>

// OLED display size
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64

// Create display object
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

// Pin assignments
#define FEED_BUTTON_PIN 2
#define POOP_BUTTON_PIN 3

// Game constants
#define MAX_FOOD 100
#define MAX_POOP 100
#define FOOD_BAR_Y 0
#define POOP_BAR_Y 8
#define BAR_HEIGHT 7
#define BAR_WIDTH 120
#define BAR_X 4
#define BAR_LABEL_X 0
#define BAR_LABEL_WIDTH 4
#define YELLOW_BAR_HEIGHT 16

// Game state
int food = MAX_FOOD / 2;
int poop = MAX_POOP / 2;
bool gameOver = false;
unsigned long lastUpdate = 0;
const unsigned long updateInterval = 1000; // ms

void drawBars() {
  // Draw yellow background for status area
  display.fillRect(0, 0, SCREEN_WIDTH, YELLOW_BAR_HEIGHT, SSD1306_WHITE);
  // Draw Food bar label (F)
  display.setTextColor(SSD1306_BLACK);
  display.setCursor(BAR_LABEL_X, FOOD_BAR_Y);
  display.print("F");
  // Draw Poop bar label (P)
  display.setCursor(BAR_LABEL_X, POOP_BAR_Y);
  display.print("P");
  // Draw Food bar
  int foodBarLen = (food * BAR_WIDTH) / MAX_FOOD;
  display.fillRect(BAR_X, FOOD_BAR_Y, foodBarLen, BAR_HEIGHT, SSD1306_BLACK);
  display.drawRect(BAR_X, FOOD_BAR_Y, BAR_WIDTH, BAR_HEIGHT, SSD1306_BLACK);
  // Draw Poop bar
  int poopBarLen = (poop * BAR_WIDTH) / MAX_POOP;
  display.fillRect(BAR_X, POOP_BAR_Y, poopBarLen, BAR_HEIGHT, SSD1306_BLACK);
  display.drawRect(BAR_X, POOP_BAR_Y, BAR_WIDTH, BAR_HEIGHT, SSD1306_BLACK);
}

void drawGameOver(const char* message) {
  display.clearDisplay();
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 24);
  display.setTextSize(1);
  display.println("GAME OVER!");
  display.println(message);
  display.display();
}

void setup() {
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    while (true); // Don't proceed, loop forever
  }
  pinMode(FEED_BUTTON_PIN, INPUT_PULLUP);
  pinMode(POOP_BUTTON_PIN, INPUT_PULLUP);
  display.clearDisplay();
  drawBars();
  display.display();
  lastUpdate = millis();
}

void loop() {
  if (gameOver) return;
  // Handle buttons (active LOW)
  bool feedPressed = digitalRead(FEED_BUTTON_PIN) == LOW;
  bool poopPressed = digitalRead(POOP_BUTTON_PIN) == LOW;
  static bool lastFeedPressed = false;
  static bool lastPoopPressed = false;

  // Feed button: increase food, increase poop a bit
  if (feedPressed && !lastFeedPressed) {
    food += 15;
    if (food > MAX_FOOD) food = MAX_FOOD;
    poop += 5;
    if (poop > MAX_POOP) poop = MAX_POOP;
  }
  // Poop button: decrease poop
  if (poopPressed && !lastPoopPressed) {
    poop -= 20;
    if (poop < 0) poop = 0;
  }
  lastFeedPressed = feedPressed;
  lastPoopPressed = poopPressed;

  // Food decreases, poop increases over time
  if (millis() - lastUpdate > updateInterval) {
    lastUpdate = millis();
    food--;
    if (food < 0) food = 0;
    if (food > 0) poop++;
    if (poop > MAX_POOP) poop = MAX_POOP;
  }

  // Check game over conditions
  if (food == 0) {
    gameOver = true;
    drawGameOver("Starved!");
    return;
  }
  if (food == MAX_FOOD) {
    gameOver = true;
    drawGameOver("Overate! Exploded!");
    return;
  }
  if (poop == MAX_POOP) {
    gameOver = true;
    drawGameOver("Poop explosion!");
    return;
  }
  if (poop == 0) {
    gameOver = true;
    drawGameOver("Constipation!");
    return;
  }

  // Redraw bars
  display.clearDisplay();
  drawBars();
  display.display();
  delay(50);
}