ANTIKETHERA MECHANISM TANIK

 #include <Wire.h>

#include <RTClib.h>

#include <Adafruit_GFX.h>

#include <Adafruit_SSD1306.h>

//

// ---- Display config ----

#define SCREEN_WIDTH 128

#define SCREEN_HEIGHT 64

#define OLED_RESET    -1         // Reset pin not used with I2C

#define OLED_ADDR     0x3C       // Change to 0x3D if your OLED uses that

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

//

// ---- RTC ----

RTC_DS3231 rtc;

//

// ---- Constants for astronomy approximations ----

// Reference new moon: 2000-01-06 18:14 UT (JD ≈ 2451550.1)

// Source: common approximation epoch for simple moon phase calc

const double NEW_MOON_JD_REF = 2451550.1;

const double SYNODIC_MONTH   = 29.53058867;

//

// ---- Utility: convert date/time to (approx) Julian Day ----

double julianDay(int y, int m, int d, int hh, int mm, int ss) {

  // Fliegel–Van Flandern algorithm (works for Gregorian dates)

  if (m <= 2) { y -= 1; m += 12; }

  int A = y / 100;

  int B = 2 - A + (A / 4);

  long C = (long)(365.25 * (y + 4716));

  long D = (long)(30.6001 * (m + 1));

  double dayFrac = (hh + (mm/60.0) + (ss/3600.0)) / 24.0;

  return C + D + d + B - 1524.5 + dayFrac;

}

//

// ---- Moon phase: age (days) and illumination (approx) ----

void moonPhase(double jd, double &ageDays, int &illumPercent) {

  double lunations = (jd - NEW_MOON_JD_REF) / SYNODIC_MONTH;

  double frac = lunations - floor(lunations);

  ageDays = frac * SYNODIC_MONTH;                            // 0..29.53

  // Illumination approximation using a simple cosine model

  // phase angle ≈ 2π * frac; illumination = (1 - cos(phase))/2

  double phaseAngle = 2.0 * PI * frac;

  double illum = 0.5 * (1.0 - cos(phaseAngle));

  illumPercent = (int)round(illum * 100.0);

}

//

// ---- Tropical zodiac from date (rough, by date ranges) ----

// Uses common Western (tropical) zodiac date boundaries.

const char* zodiacFromDate(int m, int d) {

  // date as MMDD integer for easy comparison

  int md = m*100 + d;

  if ((md >= 321  && md <= 419 )) return "Aries";

  if ((md >= 420  && md <= 520 )) return "Taurus";

  if ((md >= 521  && md <= 620 )) return "Gemini";

  if ((md >= 621  && md <= 722 )) return "Cancer";

  if ((md >= 723  && md <= 822 )) return "Leo";

  if ((md >= 823  && md <= 922 )) return "Virgo";

  if ((md >= 923  && md <= 1022)) return "Libra";

  if ((md >= 1023 && md <= 1121)) return "Scorpio";

  if ((md >= 1122 && md <= 1221)) return "Sagittarius";

  // Capricorn wraps year end

  if (md >= 1222 || md <= 119)   return "Capricorn";

  if ((md >= 120  && md <= 218 )) return "Aquarius";

  return "Pisces"; // 2/19–3/20

}

//

// ---- Cycles: Metonic (19y), Callippic (76y), Olympiad (4y) ----

int metonicYear(int year)   { return (year % 19) == 0 ? 19 : (year % 19); }

int callippicYear(int year) { int r = year % 76; return r == 0 ? 76 : r; }

int olympiadYear(int year)  { int r = year % 4;  return r == 0 ? 4  : r;  }

//

// ---- Optional: set RTC once from compile time ----

// Set to true on first upload to set the RTC, then set back to false.

bool SET_RTC_FROM_COMPILE_TIME = false;

void setup() {

  // I2C

  Wire.begin(21, 22); // ESP32 default pins; adjust if needed

  // Serial (debug)

  Serial.begin(115200);

  delay(200);

  // Display init

  if (!display.begin(SSD1306_SWITCHCAPVCC, OLED_ADDR)) {

    // If it fails, try other address or wiring

    for (;;){

      Serial.println("SSD1306 init failed. Check wiring/address.");

      delay(2000);

    }

  }

  display.clearDisplay();

  display.display();

  // RTC init

  if (!rtc.begin()) {

    showFatal("RTC not found!");

  }

  if (rtc.lostPower()) {

    Serial.println("RTC lost power, setting time to compile time.");

    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));

  } else if (SET_RTC_FROM_COMPILE_TIME) {

    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));

  }

}

void loop() {

  DateTime now = rtc.now();

  // Build Julian Day

  double jd = julianDay(now.year(), now.month(), now.day(),

                        now.hour(), now.minute(), now.second());

  // Moon

  double ageDays;

  int illum;

  moonPhase(jd, ageDays, illum);

  // Zodiac & cycles

  const char* zodiac = zodiacFromDate(now.month(), now.day());

  int metonic   = metonicYear(now.year());

  int callippic = callippicYear(now.year());

  int olympiad  = olympiadYear(now.year());

  // ---- Draw ----

  display.clearDisplay();

  // Header: time

  display.setTextSize(1);

  display.setTextColor(SSD1306_WHITE);

  display.setCursor(0, 0);

  char buf[32];

  sprintf(buf, "%02d:%02d:%02d", now.hour(), now.minute(), now.second());

  display.println(buf);

  // Date line

  sprintf(buf, "%04d-%02d-%02d", now.year(), now.month(), now.day());

  display.println(buf);

  // Moon line

  // Age with 1 decimal

  char moonBuf[32];

  dtostrf(ageDays, 5, 1, moonBuf);

  display.print("Moon: ");

  display.print(moonBuf);

  display.print(" d  ");

  display.print(illum);

  display.println("%");

  // Zodiac

  display.print("Zodiac: ");

  display.println(zodiac);

  // Cycles

  display.print("Metonic: ");

  display.print(metonic);

  display.print("  Callippic: ");

  display.println(callippic);

  display.print("Olympiad: ");

  display.print(olympiad);

  display.println(" of 4");

  // Tiny “phase bar”

  // Draw a simple horizontal bar to visualize illumination

  int barX = 0, barY = 56, barW = 128, barH = 8;

  display.drawRect(barX, barY, barW, barH, SSD1306_WHITE);

  int fillW = map(illum, 0, 100, 0, barW - 2);

  display.fillRect(barX + 1, barY + 1, fillW, barH - 2, SSD1306_WHITE);

  display.display();

  delay(250); // refresh ~4 fps

}

void showFatal(const char* msg) {

  display.clearDisplay();

  display.setTextSize(1);

  display.setTextColor(SSD1306_WHITE);

  display.setCursor(0, 0);

  display.println("FATAL:");

  display.println(msg);

  display.display();

  while (true) { delay(1000); }

}