#include <Servo.h>

const int pirPin = 2; // PIR sensor input pin
const int redLEDPin = 3; // Red LED pin (restroom off-limits)
const int greenLEDPin = 4; // Green LED pin (restroom available)
const int whiteLEDPin = 5; // White LED (lamp) pin
const int redLEDLowSanPin = 6; // Red LED pin (sanitizer low level)
const int greenLEDFullSanPin = 7; // Green LED pin (sanitizer full level)
const int switchPin = 8; // Slide switch pin (simulating water level sensor)
const int servoPin = 9; // Servo motor pin
const int trigPin = 10; // Ultrasonic sensor trig pin
const int echoPin = 11; // Ultrasonic sensor echo pin

Servo servoMotor;

void setup() {
  pinMode(pirPin, INPUT);
  pinMode(redLEDPin, OUTPUT);
  pinMode(greenLEDPin, OUTPUT);
  pinMode(whiteLEDPin, OUTPUT);
  pinMode(redLEDLowSanPin, OUTPUT);
  pinMode(greenLEDFullSanPin, OUTPUT);
  pinMode(switchPin, INPUT_PULLUP); // Enable internal pull-up resistor
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  
  servoMotor.attach(servoPin);
  
  digitalWrite(redLEDPin, LOW);
  digitalWrite(greenLEDPin, HIGH);
  digitalWrite(whiteLEDPin, LOW);
  digitalWrite(redLEDLowSanPin, LOW);
  digitalWrite(greenLEDFullSanPin, LOW);
  
  servoMotor.write(0); // Initial position of the servo motor
}

void loop() {
  // PIR Sensor Handling
  int pirState = digitalRead(pirPin);
  
  if (pirState == HIGH) { // Motion detected
    digitalWrite(whiteLEDPin, HIGH); // Turn on the lamp
    digitalWrite(redLEDPin, LOW); // Ensure the red LED is off
    digitalWrite(greenLEDPin, LOW); // Ensure the green LED is off
    delay(4000); // Simulate person using the restroom
    
    // Person exits, turn off the lamp and start sanitation process
    digitalWrite(whiteLEDPin, LOW);
    digitalWrite(redLEDPin, HIGH); // Indicate sanitation in progress
    digitalWrite(greenLEDPin, LOW); // Ensure the green LED is off
    
    // Simulate sanitizing process
    servoMotor.write(90); // Rotate servo to spray sanitizer
    delay(4000); // Wait for 5 seconds
    servoMotor.write(0); // Rotate servo back to initial position
    
    // End of sanitizing process
    digitalWrite(redLEDPin, LOW); // Turn off the red LED
    digitalWrite(greenLEDPin, HIGH); // Indicate restroom is available
  }

  // Slide Switch Handling for Sanitizer Level
  int switchState = digitalRead(switchPin);
  if (switchState == LOW) { // Switch is pressed (simulating low sanitizer level)
    digitalWrite(redLEDLowSanPin, HIGH); // Indicate low sanitizer level
    digitalWrite(greenLEDFullSanPin, LOW); // Ensure full level LED is off
  } else {
    digitalWrite(redLEDLowSanPin, LOW); // Turn off low level LED
  }

  // Ultrasonic Sensor Handling
  long duration, distance;
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  
  duration = pulseIn(echoPin, HIGH);
  distance = (duration / 2) / 29.1; // Convert to cm

  if (distance < 15) { // Adjust threshold to 15 cm
    digitalWrite(greenLEDFullSanPin, HIGH); // Indicate sanitizer is full
  } else {
    digitalWrite(greenLEDFullSanPin, LOW); // Turn off full level LED
  }
}