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

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_ADDR 0x3C

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

void setup() {
  Wire.begin();

  if (!display.begin(SSD1306_SWITCHCAPVCC, OLED_ADDR)) {
    for (;;);
  }

  scanBootAnimation();
}

void loop() {
  // Nothing yet
}

void whiteBG() {
  display.clearDisplay();
  display.fillRect(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT, SSD1306_WHITE);
}

void drawScanLine(int y) {
  // A thin black line + a tiny "shadow" above it for depth
  display.drawFastHLine(0, y, SCREEN_WIDTH, SSD1306_BLACK);
  if (y > 0) display.drawFastHLine(0, y - 2, SCREEN_WIDTH, SSD1306_BLACK);
}

void typeText(int x, int y, uint8_t size, const char* text, int perCharDelayMs) {
  display.setTextSize(size);
  display.setTextColor(SSD1306_BLACK);
  display.setCursor(x, y);

  for (int i = 0; text[i] != '\0'; i++) {
    display.print(text[i]);
    display.display();
    delay(perCharDelayMs);
  }
}

void scanBootAnimation() {
  // 1) White background
  whiteBG();
  display.display();
  delay(200);

  // 2) Scan line sweep
  for (int y = 0; y < SCREEN_HEIGHT; y += 2) {
    whiteBG();

    // Keep a tiny header marker for "device-ness"
    display.drawRect(2, 2, 20, 8, SSD1306_BLACK);
    display.fillRect(4, 4, 6, 4, SSD1306_BLACK); // little "status block"

    drawScanLine(y);

    display.display();
    delay(20);
  }

  // 3) Type in "NFC"
  whiteBG();
  display.drawRect(2, 2, 20, 8, SSD1306_BLACK);
  display.fillRect(4, 4, 6, 4, SSD1306_BLACK);
  display.display();

  typeText(18, 20, 3, "N", 0);
  delay(120);
  typeText(18 + 18, 20, 3, "F", 0);
  delay(120);
  typeText(18 + 36, 20, 3, "C", 0);
  delay(250);

  // 4) "Play" appears, then collapses to "P"
  display.setTextSize(2);
  display.setTextColor(SSD1306_BLACK);
  display.setCursor(78, 34);
  display.print("Play");
  display.display();
  delay(450);

  // Collapse effect: erase letters from right to left in chunky steps
  // Area covering "Play" at size 2 is roughly 4 chars * 12px wide = ~48px; height ~16px
  int x = 78, y = 34;
  int w = 52, h = 16;

  // Erase right side in chunks to feel "mechanical"
  for (int i = 0; i < 5; i++) {
    display.fillRect(x + (w - (i + 1) * 10), y, 10, h, SSD1306_WHITE);
    display.display();
    delay(70);
  }

  // Final: clear and draw a bold P
  display.fillRect(x, y, w, h, SSD1306_WHITE);

  display.setTextSize(3);
  display.setTextColor(SSD1306_BLACK);
  display.setCursor(78, 20);
  display.println("P");
  display.setTextSize(0.5);
  display.println("    ^INSERT MEDIA^");
  display.display();

  // "Lock" flash: invert quickly twice
  delay(120);
  display.invertDisplay(true);
  delay(60);
  display.invertDisplay(false);
  delay(80);
  display.invertDisplay(true);
  delay(40);
  display.invertDisplay(false);
}