#include <SPI.h>
#include <Wire.h>
#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

// Declaration for SSD1306 display connected using I2C
#define OLED_RESET     -1 // Reset pin # (or -1 if sharing Arduino reset pin)
#define SCREEN_ADDRESS 0x3C
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

#define BLINK_INTERVAL 1000 // Blink interval in milliseconds

// Button pin
#define BUTTON_PIN 2

// States for eye blinking
enum EyeState {
  OPEN,
  CLOSED
};

EyeState eyeState = OPEN;
unsigned long lastBlinkTime = 500;

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

  pinMode(BUTTON_PIN, INPUT_PULLUP);

  // Initialize the OLED object
  if (!display.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS)) {
    Serial.println(F("SSD1306 allocation failed"));
    for (;;); // Don't proceed, loop forever
  }

  // Clear the buffer.
  display.clearDisplay();
  display.display();
  delay(2000);
}

void loop() {
  // Check if it's time to blink the eyes
  if (millis() - lastBlinkTime >= BLINK_INTERVAL) {
    if (eyeState == OPEN) {
      // Close eyes
      display.clearDisplay();
      display.fillRect(20, 22, 31, 10, WHITE);
      display.fillRect(75, 22, 31, 10, WHITE);
      display.display();
      eyeState = CLOSED;
    } else {
      // Open eyes
      display.clearDisplay();
      display.fillRect(20, 14, 31, 24, WHITE);
      display.fillRect(75, 14, 31, 24, WHITE);
      display.display();
      eyeState = OPEN;
    }
    lastBlinkTime = millis();
  }
  // Check button press to trigger happy face
  if (digitalRead(BUTTON_PIN) == LOW) {
    display.clearDisplay();
    //Draw happy face or any other pattern you want
    display.drawRect(75, 16, 37, 17,WHITE);
    display.fillCircle(102, 24, 6,WHITE);
    display.drawRect(11, 16, 37, 17,WHITE);
    display.fillCircle(38, 24, 6,WHITE);
    display.drawLine(32, 48, 67, 58,WHITE);
    display.drawLine(68, 58, 100, 46,WHITE);
    display.drawLine(32, 48, 68, 41,WHITE);
    display.drawLine(99, 46, 67, 41,WHITE);
    display.display();
    delay(1000);    
    display.drawRect(75, 16, 37, 17,WHITE);
    display.fillCircle(83, 24, 6,WHITE);
    display.drawRect(11, 16, 37, 17,WHITE);
    display.fillCircle(20, 24, 6,WHITE);
    display.drawLine(32, 48, 67, 58,WHITE);
    display.drawLine(68, 58, 100, 46,WHITE);
    display.drawLine(32, 48, 68, 41,WHITE);
    display.drawLine(99, 46, 67, 41,WHITE);
    delay(1000); // Display happy face for 2 seconds
    display.drawRect(75, 16, 37, 17,WHITE);
    display.fillCircle(102, 24, 6,WHITE);
    display.drawRect(11, 16, 37, 17,WHITE);
    display.fillCircle(38, 24, 6,WHITE);
    display.drawLine(32, 48, 67, 58,WHITE);
    display.drawLine(68, 58, 100, 46,WHITE);
    display.drawLine(32, 48, 68, 41,WHITE);
    display.drawLine(99, 46, 67, 41,WHITE);
    display.display();
    // After displaying, clear the display to return to normal
    display.clearDisplay();
    lastBlinkTime = millis(); // Reset blink timer to maintain blinking pattern
  }
}