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

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64

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

// Clock variables
int hour = 12, minute = 0, second = 0;
unsigned long prevMillis = 0;
bool colonVisible = true;

void setup() {
  Serial.begin(115200);
  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println("OLED not found");
    while(true);
  }

  // Eye animation sequence
  eyeLookingAnimation();
  
  // Loading animation
  showLoadingScreen();
  
  // Initial clock display
  showClockHeader();
}

void loop() {
  updateClock();
}


void eyeLookingAnimation() {
  const int leftEyeX = 38, rightEyeX = 90;
  const int eyeY = 32;
  const int pupilRadius = 4;
  const int eyeRadius = 12;

  // Animation sequence (left-center-right-center)
  for(int i = 0; i < 2; i++) {
    // Look straight
    drawEyes(leftEyeX, eyeY, rightEyeX, eyeY, 0, eyeRadius, pupilRadius);
    delay(800);
    
    // Look right
    drawEyes(leftEyeX, eyeY, rightEyeX, eyeY, 6, eyeRadius, pupilRadius);
    delay(500);
    
    // Look straight
    drawEyes(leftEyeX, eyeY, rightEyeX, eyeY, 0, eyeRadius, pupilRadius);
    delay(800);
    
    // Look left
    drawEyes(leftEyeX, eyeY, rightEyeX, eyeY, -6, eyeRadius, pupilRadius);
    delay(500);
  }
  
  // Blink animation
  for(int i = 0; i < 2; i++) {
    // Open eyes
    drawEyes(leftEyeX, eyeY, rightEyeX, eyeY, 0, eyeRadius, pupilRadius);
    delay(300);
    // Closed eyes
    drawClosedEyes(leftEyeX, eyeY, rightEyeX, eyeY, eyeRadius);
    delay(300);
  }
}

void drawEyes(int leftX, int y, int rightX, int eyeY, int pupilOffset, int eyeRadius, int pupilRadius) {
  display.clearDisplay();
  
  // Draw eyebrows (position changes with look direction)
  drawEyebrows(leftX, eyeY-18, rightX, eyeY-18, pupilOffset);
  
  // Draw eye outlines
  display.drawCircle(leftX, eyeY, eyeRadius, SSD1306_WHITE);
  display.drawCircle(rightX, eyeY, eyeRadius, SSD1306_WHITE);
  
  // Draw pupils with offset
  display.fillCircle(leftX + pupilOffset, eyeY, pupilRadius, SSD1306_WHITE);
  display.fillCircle(rightX + pupilOffset, eyeY, pupilRadius, SSD1306_WHITE);
  
  display.display();
}

void drawEyebrows(int leftX, int y, int rightX, int eyebrowY, int expression) {
  // Left eyebrow
  if(expression > 0) { // Looking right - left eyebrow raised
    display.drawLine(leftX-15, eyebrowY-2, leftX+5, eyebrowY+1, SSD1306_WHITE);
  } else if(expression < 0) { // Looking left - left eyebrow lowered
    display.drawLine(leftX-15, eyebrowY+2, leftX+5, eyebrowY, SSD1306_WHITE);
  } else { // Neutral
    display.drawLine(leftX-15, eyebrowY, leftX+5, eyebrowY, SSD1306_WHITE);
  }
  
  // Right eyebrow
  if(expression > 0) { // Looking right - right eyebrow lowered
    display.drawLine(rightX-5, eyebrowY+1, rightX+15, eyebrowY-2, SSD1306_WHITE);
  } else if(expression < 0) { // Looking left - right eyebrow raised
    display.drawLine(rightX-5, eyebrowY, rightX+15, eyebrowY+2, SSD1306_WHITE);
  } else { // Neutral
    display.drawLine(rightX-5, eyebrowY, rightX+15, eyebrowY, SSD1306_WHITE);
  }
}

void drawClosedEyes(int leftX, int y, int rightX, int eyeY, int eyeRadius) {
  display.clearDisplay();
  
  // Draw straight eyebrows
  drawEyebrows(leftX, eyeY-18, rightX, eyeY-18, 0);
  
  // Draw closed eyes as arcs
  display.drawFastHLine(leftX-eyeRadius, eyeY, eyeRadius*2, SSD1306_WHITE);
  display.drawFastHLine(rightX-eyeRadius, eyeY, eyeRadius*2, SSD1306_WHITE);
  
  display.display();
}


void showLoadingScreen() {
  display.clearDisplay();
  
  // Smiley face
  display.drawCircle(64, 20, 15, SSD1306_WHITE); // Head
  display.drawPixel(60, 15, SSD1306_WHITE);      // Left eye
  display.drawPixel(68, 15, SSD1306_WHITE);      // Right eye
  display.drawLine(60, 25, 68, 25, SSD1306_WHITE); // Mouth
  
  // Loading text
  display.setTextSize(1);
  display.setCursor(35, 45);
  display.print("Initializing...");
  display.display();
  delay(1000);
  
  // Animated progress bar
  for(int i = 0; i <= 100; i+=5) {
    display.drawRect(10, 55, 108, 6, SSD1306_WHITE);
    display.fillRect(10, 55, i, 6, SSD1306_WHITE);
    display.display();
    delay(50);
  }
  delay(300);
}

// ========== CLOCK FUNCTIONS ==========
void showClockHeader() {
  display.clearDisplay();
  display.setTextColor(SSD1306_WHITE);
  display.setTextSize(1);
  display.setCursor(20, 0);
  display.println("DIGITAL CLOCK");
  display.display();
  delay(1000);
}

void updateClock() {
  unsigned long currentMillis = millis();
  if(currentMillis - prevMillis >= 1000) {
    prevMillis = currentMillis;
    second++;
    colonVisible = !colonVisible;

    if(second >= 60) {
      second = 0;
      minute++;
      if(minute >= 60) {
        minute = 0;
        hour++;
        if(hour >= 24) hour = 0;
      }
    }
    displayClock();
  }
}

void displayClock() {
  display.clearDisplay();
  
  // Header
  display.setTextSize(1);
  display.setCursor(35, 0);
  display.print("DIGITAL CLOCK");
  display.drawLine(0, 10, 127, 10, SSD1306_WHITE);
  
  // Time display
  display.setTextSize(2);
  display.setCursor(15, 25);
  if(colonVisible) {
    display.printf("%02d:%02d:%02d", hour, minute, second);
  } else {
    display.printf("%02d %02d %02d", hour, minute, second);
  }
  
  // Border
  display.drawRect(0, 0, 128, 64, SSD1306_WHITE);
  
  // Footer
  display.setTextSize(1);
  display.setCursor(28, 55);
  display.print("OLED Display");
  
  display.display();
}