#include <Servo.h>

// Pin assignments
const int servoPin = 9;
const int ledPin   = 13;
const int btn1Pin  = 22;  // Increment servo angle (+30)
const int btn2Pin  = 23;  // Decrement servo angle (-30)

// Servo limits and step increment
const int minAngle = 0;
const int maxAngle = 180;
const int stepSize = 30;
int currentAngle = 90;  // starting angle

Servo servo1;

// Debounce time (milliseconds)
const unsigned long debounceDelay = 150;

// Function to smoothly move the servo from startAngle to endAngle
void smoothMove(int startAngle, int endAngle) {
  int direction = (endAngle > startAngle) ? 1 : -1;
  int diff = abs(endAngle - startAngle);
  // Determine how long to delay per degree such that the total time is at least 2 seconds.
  // For example, if diff is 30 degrees then delay per degree = 2000 ms / 30 ≈ 67 ms.
  int stepDelay = 2000 / (diff > 0 ? diff : 1);

  // Move smoothly one degree at a time
  for (int pos = startAngle; pos != endAngle; pos += direction) {
    servo1.write(pos);
    delay(stepDelay);
  }
  // Final command to ensure it reaches the exact target angle
  servo1.write(endAngle);
}

void setup() {
  // Initialize serial monitor (optional)
  Serial.begin(9600);
  
  // Attach the servo to the designated pin and set initial angle.
  servo1.attach(servoPin);
  servo1.write(currentAngle);

  // Setup LED pin
  pinMode(ledPin, OUTPUT);
  digitalWrite(ledPin, LOW);  // LED off

  // Setup push button pins with internal pull-up resistors.
  pinMode(btn1Pin, INPUT_PULLUP);
  pinMode(btn2Pin, INPUT_PULLUP);
}

void loop() {
  // Check btn1: increment servo (if not at maximum)
  if (digitalRead(btn1Pin) == LOW) { // button pressed (active LOW)
    delay(debounceDelay); // debounce delay
    if (digitalRead(btn1Pin) == LOW) { // confirm press after debounce
      if (currentAngle < maxAngle) {
        int newAngle = currentAngle + stepSize;
        if (newAngle > maxAngle) {
          newAngle = maxAngle;
        }
        // Turn on LED while moving
        digitalWrite(ledPin, HIGH);
        Serial.print("Moving servo from ");
        Serial.print(currentAngle);
        Serial.print(" to ");
        Serial.println(newAngle);
        smoothMove(currentAngle, newAngle);
        // Update current angle and turn off LED
        currentAngle = newAngle;
        digitalWrite(ledPin, LOW);
      }
      // Wait until btn1 is released to avoid multiple triggers
      while (digitalRead(btn1Pin) == LOW) {
        delay(10);
      }
    }
  }
  
  // Check btn2: decrement servo (if not at minimum)
  if (digitalRead(btn2Pin) == LOW) { // button pressed (active LOW)
    delay(debounceDelay); // debounce delay
    if (digitalRead(btn2Pin) == LOW) { // confirm press after debounce
      if (currentAngle > minAngle) {
        int newAngle = currentAngle - stepSize;
        if (newAngle < minAngle) {
          newAngle = minAngle;
        }
        // Turn on LED while moving
        digitalWrite(ledPin, HIGH);
        Serial.print("Moving servo from ");
        Serial.print(currentAngle);
        Serial.print(" to ");
        Serial.println(newAngle);
        smoothMove(currentAngle, newAngle);
        // Update current angle and turn off LED
        currentAngle = newAngle;
        digitalWrite(ledPin, LOW);
      }
      // Wait until btn2 is released to avoid multiple triggers
      while (digitalRead(btn2Pin) == LOW) {
        delay(10);
      }
    }
  }
  
  // Short delay to allow other events; prevents bouncing in software loop
  delay(10);
}