#include <Servo.h>
Servo myservo;  // create Servo object to control a servo
int pos = 0;

int currenthour = 14;
int currentminute = 48;
float currentminutedecimal = currentminute / 60.0;
float currenttime = currenthour + currentminutedecimal;

int sunrisehour = 7;
int sunriseminute = 47;
float sunriseminutedecimal = sunriseminute / 60.0;
float sunrise = sunrisehour + sunriseminutedecimal;

int sunsethour = 18;
int sunsetminute = 48;
float sunsetminutedecimal = sunsetminute / 60.0;
float sunset = sunsethour + sunsetminutedecimal;

float elapsedhours = (currenttime - sunrise);  // hours between NOW and sunrise
float elapsedangle = elapsedhours * 15.0;  // hours * degrees per hour

int degreesperhour = 15;  // Earth rotates 15 degrees per hour
float degreesperminute = degreesperhour / 60;
float degreespersecond = degreesperminute / 60;

float sunriseangle = (sunset - sunrise) * 15;
float currentangle = 180 - sunriseangle + elapsedangle;
float sunsetangle = 180 - sunriseangle;

unsigned long timer, timeout = 1000;

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

void loop() {
  if (millis() - timer > timeout) {
    timer = millis();
    currentangle += degreespersecond;
    report();
    myservo.write(currentangle);
  }
}

void pad(float value) {
  if (value < 100) Serial.print(" ");
  if (value < 10) Serial.print(" ");
  Serial.print(value);
}

void report() {
  for (int i = 0; i < 36; i++)
    Serial.print("=");
  Serial.println();

  Serial.print("Sunrise (time:");
  pad(sunrise);
  Serial.print(") (angle:");
  pad(sunriseangle);
  Serial.println(")");

  Serial.print("Current (time:");
  pad(currenttime);
  Serial.print(") (angle:");
  pad(currentangle);
  Serial.println(")");

  Serial.print("Elapsed (time:");
  pad(elapsedhours);
  Serial.print(") (angle:");
  pad(elapsedangle);
  Serial.println(")");

  Serial.print("Sunset  (time:");
  pad(sunset);
  Serial.print(") (angle:");
  pad(sunsetangle);
  Serial.println(")");

  myservo.attach(3);
  myservo.write(currentangle);
}