/*
 * A circuit that contains 3 different LED lights that turn on and off based on the 
 * position of the servo handle.
 *
 * https://wokwi.com/projects/402606526410158081
 *
 * Jason Hull
 * COSI 521
 */

#include <Servo.h>

const int BLUE_PIN = 11;
const int RED_PIN = 12;
const int YELLOW_PIN = 13;

Servo myservo;

void setup() {
  // Set the pins for the LEDs
  pinMode(BLUE_PIN, OUTPUT);
  pinMode(RED_PIN, OUTPUT);
  pinMode(YELLOW_PIN, OUTPUT);

  // Start powered down
  digitalWrite(BLUE_PIN, LOW);
  digitalWrite(RED_PIN, LOW);  
  digitalWrite(YELLOW_PIN, LOW);

  // Config the servo and move to zero
  myservo.attach(9);
  myservo.write(0);
  delay(333);
}

/* move the servo in 90 degree increments and change the LEDs along the way */
void loop() {
  move(BLUE_PIN, RED_PIN, 0, 90);
  move(RED_PIN, BLUE_PIN, 90, 180);
  move(YELLOW_PIN, RED_PIN, 180, 90);
  move(RED_PIN, YELLOW_PIN, 90, 0);
}

void move(int led_on_pin, int led_off_pin, int move_from_deg, int move_to_deg) {
  // change the LEDs
  digitalWrite(led_on_pin, HIGH);
  digitalWrite(led_off_pin, LOW);

  // move the servo - may be forward or reverse
  int increment = move_from_deg < move_to_deg ? 1 : -1;
  int current_pos_deg = move_from_deg;

  while (current_pos_deg != move_to_deg) {
    current_pos_deg += increment;
    myservo.write(current_pos_deg);
    delay(20);
  }
}