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

// OLED Configuration
#define OLED_RESET -1
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 32
#define SSD1306_I2C_ADDRESS 0x3C
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

// Button Pin Definitions
#define STOP_BUTTON_PIN 2

// Function Prototypes
void showSplashScreen();
bool checkButtonInterrupt();

void setup() {
  Serial.begin(115200);

  // Initialize buttons with pull-up resistors
  pinMode(STOP_BUTTON_PIN, INPUT_PULLUP);

  // Initialize OLED
  if (!display.begin(SSD1306_SWITCHCAPVCC, SSD1306_I2C_ADDRESS)) {
    Serial.println(F("SSD1306 initialization failed"));
    for (;;);
  }

  showSplashScreen();  // STARTS UNSTOPPABLE ANIMATION
}

void loop() {
  // Your main code goes here AFTER interrupt
  display.clearDisplay();
  display.setCursor(0, 0);
  display.setTextSize(1);
  display.println(F("Main Menu Ready!"));
  display.display();
  
  while (true) {  // Stay in main menu forever
    delay(1000);
  }
}

// === UNSTOPPABLE ANIMATION ===
void showSplashScreen() {
  int dotCount = 0;
  
  Serial.println(F("🚀 UNSTOPPABLE PAKFONES Animation Started!"));
  
  // FOREVER LOOP until button interrupt
  while (true) {
    // CHECK FOR ANY BUTTON PRESS (interrupt)
    if (checkButtonInterrupt()) {
      Serial.println(F("⏹️ Animation interrupted!"));
      display.clearDisplay();
      display.display();
      return;  // EXIT to main loop
    }
    
    display.clearDisplay();
    
    // MAIN TITLE
    display.setTextSize(2);
    display.setTextColor(SSD1306_WHITE);
    display.setCursor(15, 20);
    display.println(F("PAKFONES"));
    
    // THREE DOTS ANIMATION (smaller, centered)
    display.setTextSize(1);
    display.setCursor(60, 35);
    
    // CYCLE: . → .. → ...
    switch (dotCount % 3) {
      case 0: 
        display.print(F(".")); 
        Serial.println(F("PAKFONES .")); 
        break;
      case 1: 
        display.print(F("..")); 
        Serial.println(F("PAKFONES ..")); 
        break;
      case 2: 
        display.print(F("...")); 
        Serial.println(F("PAKFONES ...")); 
        break;
    }
    
    display.display();
    delay(500);  // Animation speed
    dotCount++;  // RESTARTS from 0 automatically (%3)
  }
}

// === INTERRUPT CHECKER ===
bool checkButtonInterrupt() {
  // ANY BUTTON PRESS STOPS ANIMATION
  if (digitalRead(STOP_BUTTON_PIN) == LOW) {
    delay(50);  // Debounce
    return true;
  }
  return false;
}